U.S. patent application number 14/004724 was filed with the patent office on 2014-09-11 for work vehicle.
The applicant listed for this patent is KOMATSU LTD.. Invention is credited to Takeshi Ikeda, Hitoshi Katayanagi, Osamu Kuroyanagi, Jun Matsumoto, Masamichi Miyazaki, Kouji Nagami, Masaru Satou, Takahiro Shimojo.
Application Number | 20140252803 14/004724 |
Document ID | / |
Family ID | 50036598 |
Filed Date | 2014-09-11 |
United States Patent
Application |
20140252803 |
Kind Code |
A1 |
Matsumoto; Jun ; et
al. |
September 11, 2014 |
WORK VEHICLE
Abstract
Provided is a work vehicle in which a positioning antenna can be
installed above a roof plate of a cab at an accurate position and
in a proper attitude while preventing a positioning accuracy from
being decreased by vibrations. The work vehicle includes a first
mount member, a second mount member and a positioning antenna. The
first mount member includes a left-side member fixed on the roof
beam at the left side and a right-side member fixed on the roof
beam at the right side. The second mount member is disposed above
the roof plate across the left-side member and the right-side
member. The positioning antenna is mounted on the second mount
member.
Inventors: |
Matsumoto; Jun;
(Hirakata-shi, JP) ; Miyazaki; Masamichi;
(Neyagawa-shi, JP) ; Satou; Masaru; (Hirakata-shi,
JP) ; Nagami; Kouji; (Southampton, GB) ;
Ikeda; Takeshi; (Hirakata-shi, JP) ; Katayanagi;
Hitoshi; (Hirakata-shi, JP) ; Kuroyanagi; Osamu;
(Hirakata-shi, JP) ; Shimojo; Takahiro;
(Komatsu-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KOMATSU LTD. |
Tokyo |
|
JP |
|
|
Family ID: |
50036598 |
Appl. No.: |
14/004724 |
Filed: |
March 8, 2013 |
PCT Filed: |
March 8, 2013 |
PCT NO: |
PCT/JP2013/056421 |
371 Date: |
September 12, 2013 |
Current U.S.
Class: |
296/190.01 |
Current CPC
Class: |
H01Q 1/3275 20130101;
E02F 9/0858 20130101; E02F 9/163 20130101; G01S 19/35 20130101;
E02F 9/26 20130101 |
Class at
Publication: |
296/190.01 |
International
Class: |
E02F 9/16 20060101
E02F009/16 |
Claims
1. A work vehicle comprising: a work implement; a cab to be boarded
with an operator to operate said work implement, said cab including
a lateral pair of roof beams disposed respectively on the top of
both side surfaces of said cab and a roof plate supported
respectively by said pair of roof beams; a first mount member
including a left-side member fixed on said roof beam at the left
side and a right-side member fixed on said roof beam at the right
side; a second mount member disposed above said roof plate across
said left-side member and said right-side member; and a positioning
antenna mounted on said second mount member.
2. The work vehicle according to claim 1, wherein said roof plate
is convexly curved upward.
3. The work vehicle according to claim 1, wherein a gap is formed
between said second mount member and said roof plate.
4. The work vehicle according to claim 3, further comprising an
antenna cable connected to said positioning antenna, wherein a part
of said antenna cable is disposed inside said gap.
5. The work vehicle according to claim 1, wherein said left-side
member and said right-side member are welded on upper surfaces of
said roof beams.
6. The work vehicle according to claim 1, wherein said cab further
includes a width-direction roof beam disposed on the top of said
cab and extending in the width direction of said work vehicle, said
first mount member further includes a width-direction member fixed
on said width-direction roof beam, and said second member is
supported by said width-direction member.
7. The work vehicle according to claim 1, wherein said second mount
member has an antenna installation surface, and said positioning
antenna is mounted on said antenna installation surface, and said
antenna installation surface has a planar shape.
Description
TECHNICAL FIELD
[0001] The present invention relates to a work vehicle, and in
particular, relates to a work vehicle equipped with a cab to be
boarded with an operator.
BACKGROUND ART
[0002] Information-and-Communication-Technology intensive
constructions have been performed on a work vehicle having a work
implement by using a satellite navigation system to determine a
position of the work implement in real time so as to improve work
efficiency thereof. Conventionally, there has been disclosed a work
vehicle which has a pole disposed on an upper edge of a work
implement, and on an upper end of the pole, a GNSS (Global
Navigation Satellite System) antenna is installed (for example, see
Japanese Patent Laying-Open No. 10-38570 (PTD 1)).
[0003] In the case where the work vehicle is a bulldozer, in
performing operations such as dozing and grading, the work
implement is subjected to great vibrations, which decrease a
positioning accuracy of the GNSS antenna disposed on the work
implement. When the work implement is subjected to vibrations, the
pole may vibrate, and an antenna cable connected to the GNSS
antenna may contact earth or sands. Accordingly, a technique has
been proposed to install the GNSS antenna on a roof of a cab to be
boarded with an operator.
CITATION LIST
Patent Document
[0004] PTD 1: Japanese Patent Laying-Open No. 10-38570
SUMMARY OF INVENTION
Technical Problem
[0005] In a conventional work vehicle, a roof surface of a cab is
formed by fixing a planar roof plate on frame-shaped beams. The
roof plate is convexly curved upward to prevent water from being
accumulated on a top surface thereof. Thereby, when installing a
positioning antenna on the top surface of the roof plate, since the
roof plate is curved, it is difficult to install the positioning
antenna at an accurate position and in a proper attitude.
[0006] The present invention has been accomplished in view of the
aforementioned problems, and it is therefore an object of the
present invention to provide a work vehicle in which a positioning
antenna can be installed above a roof plate of a cab at an accurate
position and in a proper attitude while preventing a positioning
accuracy from being decreased by vibrations.
Solution to Problem
[0007] The work vehicle of the present invention includes a work
implement, and a cab to be boarded with an operator to operate the
work implement. The cab includes a lateral pair of roof beams
disposed respectively on the top of both side surfaces of the cab
and a roof plate supported respectively by the pair of roof beams.
The work vehicle further includes a first mount member, a second
mount member and a positioning antenna. The first mount member
includes a left-side member fixed on the roof beam at the left side
and a right-side member fixed on the roof beam at the right side.
The second mount member is disposed above the roof plate across the
left-side member and the right-side member. The positioning antenna
is mounted on the second mount member.
[0008] According to the work vehicle of the present invention, the
positioning antenna is installed relatively on a strong structure
constructed by the roof beams of the cab through the intermediary
of the first mount member and the second mount member, and thereby,
it is possible to prevent the positioning accuracy from being
decreased by vibrations and it is possible to install the
positioning antenna above the roof plate at an accurate position
and in a proper attitude.
[0009] In the work vehicle mentioned above, the roof plate is
convexly curved upward. Thus, by fixing the first mount member on
the lateral pair of roof beams and disposing the second mount
member on the first mount member, it is possible to dispose the
positioning antenna without being affected by the shape of the roof
plate. Thereby, the positioning antenna can be installed with more
certainty above the roof plate at an accurate position and in a
proper attitude.
[0010] In the work vehicle mentioned above, a gap is formed between
the second mount member and the roof plate. Thereby, it is possible
to prevent the second mount member from being interfered by the
roof plate, enabling the positioning antenna to be mounted on the
second mount member at an accurate position and in a proper
attitude.
[0011] The work vehicle mentioned above further includes an antenna
cable connected to the positioning antenna. A part of the antenna
cable is disposed inside the gap formed between the second mount
member and the roof plate. Thereby, the part of the antenna cable
is disposed below the second mount member and invisible from the
outside, improving the outer appearance of the work vehicle.
[0012] In the work vehicle mentioned above, the left-side member
and the right-side member are welded on upper surfaces of the roof
beams. Thereby, there is no need to perform a processing such as
perforating holes in the roof beams in order to fix the left-side
member and the right-side member on the roof beams. Accordingly, it
is possible to maintain the strength of the roof beams, preventing
the strength of the cab from being decreased with certainty.
[0013] In the work vehicle mentioned above, the cab further
includes a width-direction roof beam disposed on the top of the cab
and extending in the width direction of the work vehicle. The first
mount member further includes a width-direction member fixed on the
width-direction roof beam. The second member is supported by the
width-direction member. Thereby, the second mount member is
supported by the left-side member, the right-side member and the
width-direction member, enabling the second mount member to be
disposed above the roof plate more stable.
[0014] In the work vehicle mentioned above, the second mount member
has an antenna installation surface. The positioning antenna is
mounted on the antenna installation surface. The antenna
installation surface has a planar shape. Thereby, it is easier to
mount the positioning antenna on the antenna installation surface
at an accurate position and in a proper attitude.
Advantageous Effects of Invention
[0015] According to the present invention as described above, it is
possible to install the positioning antenna above the roof plate of
the cab at an accurate position and in a proper attitude while
preventing the positioning accuracy from being decreased by
vibrations.
BRIEF DESCRIPTION OF DRAWINGS
[0016] FIG. 1 is a side view schematically illustrating a structure
of a work vehicle according to an embodiment of the present
invention;
[0017] FIG. 2 is an exploded perspective view schematically
illustrating the structure of the work vehicle according to an
embodiment of the present invention;
[0018] FIG. 3 is a perspective view schematically illustrating a
structure of a cab of the work vehicle according to an embodiment
of the present invention;
[0019] FIG. 4 is a sectional view schematically illustrating a roof
plate along a line IV-IV in FIG. 3;
[0020] FIG. 5 is a perspective view schematically illustrating a
structure of a mount unit for mounting a positioning antenna
according to an embodiment of the present invention;
[0021] FIG. 6 is an exploded perspective view schematically
illustrating the mount unit for mounting the positioning antenna
according to an embodiment of the present invention;
[0022] FIG. 7 is a perspective view schematically illustrating a
state where a first mount member is fixed on a roof portion of the
cab;
[0023] FIG. 8 is a sectional view schematically illustrating the
mount unit along a line VIII-VIII in FIG. 6;
[0024] FIG. 9 is a sectional view schematically illustrating the
first mount member along a line IX-IX in FIG. 7;
[0025] FIG. 10 is a sectional view schematically illustrating the
first mount member along a line X-X in FIG. 7; and
[0026] FIG. 11 is a bottom view schematically illustrating a
structure of a second mount member.
DESCRIPTION OF EMBODIMENTS
[0027] Hereinafter, an embodiment of the present invention will be
described with reference to the drawings.
[0028] With reference to FIG. 1, a bulldozer 30, which serves as a
work vehicle of the present invention, mainly includes a cab 1, an
engine compartment 34, a hydraulic oil tank module 35, a pair of
track frame modules 37, and a dozing blade 38. Cab 1 is a
box-shaped structure which forms an interior room space for an
operator OP operating bulldozer 30 to enter. With reference to FIG.
2, bulldozer 30 further includes a vehicle frame 31, an engine 32,
an engine cooling module 33, and a fuel tank module 36.
[0029] Vehicle frame 31 has a front end and a rear end. Cab 1 is
mounted on vehicle frame 31 between the front end and the rear end
of vehicle frame 31. Cab 1 is equipped with a seat for operator OP
to sit on, a manipulation mechanism such as a pedal and a lever,
and an instrument panel or the like. Operator OP boards cab 1 to
drive bulldozer 30 and operate dozing blade 38. In the present
embodiment, when operator OP is seated in cab 1, the direction to a
left side of operator OP, the direction to a right side thereof,
the direction to a front side thereof, and the direction to a rear
side thereof are referred to the left side, the right side, the
front side and the rear side, respectively.
[0030] Engine 32 is mounted on vehicle frame 31 at a front position
of vehicle frame 31 ahead of cab 1. Engine compartment 34 covers
engine 32. Cab 1 is disposed posterior to engine 32 covered by
engine compartment 34.
[0031] Hydraulic oil tank module 35 is configured to store
hydraulic oil for activating a work implement such as dozing blade
38 or the like of bulldozer 30, and is disposed at one side of cab
1. Fuel tank module 36 is configured to store fuel to be supplied
to engine 32, and is disposed at the other side of cab 1.
[0032] Engine cooling module 33 is configured to cool engine 32 or
the like, and is mounted on vehicle frame 31 at the rear end of
vehicle frame 31. A cooling fan of engine cooling module 33 may be
electrically driven by an electric motor or hydraulically driven by
a hydraulic motor or the like, independently of engine 32. It is
preferable that the fan is driven hydraulically at a variable
speed. Engine cooling module 33 is disposed posterior to cab 1 at a
position between a rear end of hydraulic oil tank module 35 and a
rear end of fuel tank module 36.
[0033] The paired track frame modules 37 are disposed at the left
side and the right side of vehicle frame 31, respectively. Dozing
blade 38 is disposed anterior to the front end of vehicle frame 31.
Operator OP inside cab 1 operates dozing blade 38 by using the
manipulation mechanism to perform operations such as dozing and
grading and the like.
[0034] A positioning antenna 50 configured to determine a present
position of the work implement is installed on a roof portion of
cab 1. Cab 1 includes a roof plate 2 to be described hereinafter,
and positioning antenna 50 is disposed above roof plate 2. Through
the intermediary of a first mount member 10 and a second mount
member 20, which will be described hereinafter, positioning antenna
50 is mounted upper to the roof portion of cab 1.
[0035] Positioning antenna 50 is configured to receive radio waves
containing a navigation signal from satellites 121 and 122. A
controller and a display (both not shown) are disposed in cab 1.
The controller, based on the signal received by positioning antenna
50, computes a present position of positioning antenna 50, and
thereafter, based on the computation result, computes a present
position of dozing blade 38 accurately and precisely. The present
position of dozing blade 38 is updated and displayed on the display
in real time, and thereby, operator OP boarding in cab 1 can
confirm the operation status constantly.
[0036] With reference to FIG. 3, cab 1 includes a plurality of
pillars. The plurality of pillars are disposed with the
longitudinal direction of each pillar extending in the vertical
direction. The plurality of pillars include a pair of front pillars
3 disposed in the front of cab 1, a pair of rear pillars 5 disposed
in the rear of cab 1, and a pair of central pillars 4 disposed in a
center portion of cab 1 in the anteroposterior direction. Front
pillars 3, central pillars 4 and rear pillars 5 are arranged in a
sequence from the front of cab 1 toward the rear thereof. End
portions of the pair of central pillars 4 and the pair of rear
pillars 5, respectively, are welded on a floor plate (not
shown).
[0037] Cab 1 further includes a left-side roof beam 7 joining both
upper ends of central pillar 4 and rear pillar 5 at the left side,
and a right-side roof beam 8 joining both upper ends of central
pillar 4 and rear pillar 5 at the right side. Thus, cab 1 includes
a lateral pair of roof beams disposed at upper ends of both sides
of cab 1. Left-side roof beam 7 and right-side roof beam 8 are
arranged to have the longitudinal direction thereof extending in
the anteroposterior direction. Left-side roof beam 7 is supported
by central pillar 4 and rear pillar 5 at the left side. Right-side
roof beam 8 is supported by central pillar 4 and rear pillar 5 at
the right side.
[0038] Cab 1 further includes a width-direction roof beam 9a
joining upper ends of the pair of rear pillars 5, respectively.
Width-direction roof beam 9a is arranged to have the longitudinal
direction thereof extending in the width direction (lateral
direction) of cab 1. Both ends of width-direction roof beam 9a are
connected respectively to rear ends of left-side roof beam 7 and
right-side roof beam 8 and fixed through welding. Width-direction
roof beam 9a is disposed on the top of cab 1 at the rear side.
[0039] Cab 1 further includes a width-direction roof beam 9b
joining upper ends of the pair of central pillars 4, respectively.
Width-direction roof beam 9b is arranged to have the longitudinal
direction thereof extending in the width direction (lateral
direction) of cab 1. Both ends of width-direction roof beam 9b are
connected respectively to the ends of left-side roof beam 7 and
right-side roof beam 8 at the front side and fixed through welding.
Left-side roof beam 7, right-side roof beam 8 and width-direction
roof beams 9a and 9b constitute a part of structural materials for
the roof of cab 1.
[0040] Cab 1 further includes roof plate 2 made from a plate
member. Roof plate 2 forms a roof surface of cab 1. Roof plate 2 is
supported by the lateral pair of roof beams, i.e., left-side roof
beam 7 and right-side roof beam 8, and width-direction roof beams
9a and 9b, respectively. A left-side edge of roof plate 2 is
disposed on left-side roof beam 7, and fixed on left-side roof beam
7 through welding. A right-side edge of roof plate 2 is disposed on
right-side roof beam 8, and fixed on the upper surfaces of
right-side roof beam 8 through welding. A rear-side edge of roof
plate 2 is disposed on width-direction roof beam 9a, and fixed on
the top surfaces of width-direction roof beam 9a through
welding.
[0041] As mentioned above, cab 1 has a structure obtained by
joining the pair of central pillars 4, the pair of rear pillars 5,
the floor plate, left-side and right-side roof beams 7 and 8, and
width-direction roof beams 9a and 9b through welding, respectively.
In addition, such structure serves as a rollover protection
structure. The rollover protection structure has an improved
structural strength and is configured to protect operator OP
sitting with a seat belt on the seat in cab 1 when the work vehicle
rolls over.
[0042] FIG. 4 illustrates a sectional view along a line IV-IV in
FIG. 3. With reference to FIG. 4, roof plate 2 includes an upper
surface 2a and a lower surface 2b. Upper surface 2a and lower
surface 2b form primary surfaces of plate-shaped roof plate 2. Roof
plate 2 has a convex shape protruding upward. Roof plate 2, which
has a shape by bending a flat plate having primary surfaces in
planar shape into the convex shape, is mounted on the upper
surfaces of left-side roof beam 7, right-side roof beam 8 and
width-direction roof beams 9a and 9b with the convex shape formed
according to the bending deformation of the flat plate pointing
upward. Upward curving edges of roof plate 2 are welded on
left-side roof beam 7, right-side roof beam 8 and width-direction
roof beams 9a and 9b, and thereby, roof plate 2 is fixed at cab 1,
with the central portion thereof protruding upward higher than the
edges thereof.
[0043] Hereinafter, a structure in which positioning antenna 50 is
mounted above roof plate 2 of cab 1 will be described in detail.
With reference to FIG. 5, positioning antenna 50 includes an
antenna main body 51 having a receiving function, and a support
member 52 supporting antenna main body 51 from below. Support
member 52 is installed on second mount member 20. Positioning
antenna 50 is mounted on second mount member 20 at a central
portion. Positioning antenna 50 is designed to be detachable from
second mount member 20 so as to comply with height regulations in
transporting bulldozer 30.
[0044] Second mount member 20 is formed with a plurality of holes
25 and 26. Holes 25 and 26 are formed in such a way that they
penetrate second mount member 20 in the thickness direction
thereof. Holes 25 are formed at both lateral edges of second mount
member 20. Second mount member 20 is fixed to left-side roof beam 7
and right-side roof beam 8 through bolts penetrating holes 25 in
the vertical direction. Holes 26 are formed at the rear edge of
second mount member 20. Second mount member 20 is fixed to
width-direction roof beam 9a through bolts penetrating holes 26 in
the vertical direction. If the fixing through bolts is disengaged,
it is possible to detach second mount member 20 from the roof of
cab 1; thereby, in transporting bulldozer 30, positioning antenna
50 and second mount member 20 may be detached from cab 1 as a
whole.
[0045] Positioning antenna 50 is connected with an antenna cable
56. Antenna cable 56 is an electric cable configured to perform
data communications with and supply power to positioning antenna
50. Second mount member 20 is formed with a through hole 27
penetrating second mount member 20 in the thickness direction
thereof nearby the position where positioning antenna 50 is
mounted. Through hole 27 has a diameter sufficiently greater than
the outer diameter of antenna cable 56. Second mount member 20
includes an antenna cable outdrawing member 28 disposed above
left-side roof beam 7. Antenna cable outdrawing member 28 is formed
with a through hole 29. Through hole 29 has a diameter
substantially equal to the outer diameter of antenna cable 56.
[0046] Antenna cable 56 is provided with a stopper member 57 which
is disposed around an end portion of the antenna cable to which
position antenna 50 is connected. Stopper member 57 is configured
to prevent antenna cable 56 from getting disengaged from
positioning antenna 50 by preventing a nut used to join antenna
cable 56 and positioning antenna 50 from loosing.
[0047] With reference to FIG. 6, a left-side member 17 is fixed on
the upper surfaces of left-side roof beam 7. Similar to left-side
roof beam 7, left-side member 17 is arranged to have the
longitudinal direction thereof extending in the anteroposterior
direction. A right-side member 18 is fixed on right-side roof beam
8. Similar to right-side roof beam 8, right-side member 18 is
arranged to have the longitudinal direction thereof extending in
the anteroposterior direction. Second mount member 20 is disposed
above roof plate 2 across left-side member 17 and right-side member
18, and supported by both left-side member 17 and right-side member
18.
[0048] Left-side member 17 and right-side member 18 are formed with
a plurality of screw tap holes 15. Screw tap holes 15 are formed at
positions in respective correspondence with holes 25 formed in
second mount member 20. Screw tap holes 15 are formed by boring
from upper surfaces of left-side member 17 and right-side member 18
downward to a depth not penetrating left-side member 17 and
right-side member 18. A bolt is inserted through hole 25 formed in
second mount member 20 and engaged in screw tap hole 15 through
screwing with an inner wall face thereof, and accordingly,
left-side member 17, right-side member 18 and second mount member
20 are fixed together through bolts.
[0049] With reference to FIG. 7, a width-direction member 19 is
fixed on width-direction roof beam 9a. Similar to width-direction
roof beam 9a, width-direction member 19 is arranged to have the
longitudinal direction thereof extending in the width direction of
cab 1. Thereby, second mount member 20 has two lateral edges
thereof supported by left-side member 17 and right-side member 18,
and has the rear edge thereof further supported by width-direction
member 19. Left-side member 17, right-side member 18 and
width-direction member 19 constitute first mount member 10. First
mount member 10 is interposed between the roof beams of cab 1 and
second mount member 20.
[0050] Width-direction member 19 is formed with a plurality of
screw tap holes 16. Screw tap holes 16 are formed at positions in
respective correspondence with holes 26 formed in second mount
member 20. Screw tap holes 16 are formed by boring from the upper
surface of width-direction member 19 downward to a depth not
penetrating width-direction member 19. A bolt is inserted through
hole 26 formed in second mount member 20 and engaged in screw tap
hole 16 through screwing with an inner wall face thereof, and
accordingly, second mount member 20 and width-direction member 19
are fixed together through bolts.
[0051] First mount member 10 is fixed on the roof beams of cab 1,
second mount member 20 is fixed on first mount member 10, and
positioning antenna 50 is mounted on second mount member 20. Thus,
positioning antenna 50 is mounted above roof plate 2 of cab 1
through the intermediary of first mount member 10 and second mount
member 20. First mount member 10 and second mount member 20
constitute a mount unit for installing positioning antenna 50 above
roof plate 2.
[0052] FIG. 8 illustrates a sectional view along a line VIII-VIII
in FIG. 6. With reference to FIG. 8, roof plate 2 is fixed directly
on the upper surfaces of left-side roof beam 7 and width-direction
roof beam 9a. Second mount member 20 is supported by left-side roof
beam 7 and right-side roof beam 8 through the intermediary of
left-side member 17 and right-side member 18 which is not shown in
FIG. 8. Second mount member 20 includes a top plate 21. Top plate
21 has a planar shape and includes an upper primary surface, i.e.,
an antenna installation surface 21a, and a lower primary surface,
i.e., a rear surface 21b. Antenna installation surface 21a forms
the upper surface of second mount member 20 and has a planar shape.
Positioning antenna 50 is mounted on antenna installation surface
21a.
[0053] Second mount member 20 further includes a horizontal support
member 24 supporting top plate 21 from the side of rear surface 21b
thereof. Horizontal support member 24 is arranged to have the
longitudinal direction thereof extending in the width direction
(lateral direction) of cab 1. In the vertical direction, horizontal
support member 24 is disposed on left-side member 17. Top plate 21
is disposed on horizontal support member 24. Thereby, a hollow gap
G is formed between rear surface 21b of top plate 21 included in
second mount member 20 and roof plate 2. Since gap G is formed
between second mount member 20 and roof plate 2, second mount
member 20 is disposed without contacting roof plate 2.
[0054] Antenna main body 51 of positioning antenna 50 is disposed
at the side of antenna installation surface 21a of top plate 21.
Antenna cable 56 connected to antenna main body 51 is disposed in
such a way that it is inserted into through hole 27 formed in
second mount member 20, extends in the lateral direction of cab 1
to pass across gap G below second mount member 20 to antenna cable
outdrawing member 28. A part of antenna cable 56 is disposed in gap
G between top plate 21 of second mount member 20 and roof plate 2.
Antenna cable 56 is retained in gap G by a plurality of retaining
members disposed on rear surface 21b of top plate 21. Antenna cable
56 extends from gap G below second mount member 20 to the outside
of the side surface of cab 1 via through hole 29 formed in antenna
cable outdrawing member 28.
[0055] With reference to FIG. 9, roof plate 2 is fixed directly on
the upper surfaces of left-side roof beam 7 and width-direction
roof beam 9a. Left-side roof beam 7 has a pipe structure, and has a
deformed-pipe shape whose cross-sectional shape is non-circular but
bent and complicated. Thereby, left-side roof beam 7 has a section
stiffness stronger than roof plate 2. Left-side member 17 is welded
on the upper surfaces of left-side roof beam 7, and thereby,
left-side member 17 is fixed integrally to left-side roof beam 7.
Left-side member 17 is disposed to protrude upward relative to the
upper surface of left-side roof beam 7. Left-side member 17 is
fixed directly on left-side roof beam 7 at a position on the
surface of left-side roof beam 7 without overlapping with roof
plate 2. Left-side member 17 is disposed leftward to the left edge
of roof plate 2. The upper surface of left-side member 17 is
configured to be higher than the upper surface of roof plate 2 in
the vertical direction.
[0056] In FIG. 9, the structure at the left side of cab 1 is
illustrated; however, at the right side of cab 1, a structure is
formed in line symmetry to the structure at the left side with
respect to a line extending in the vertical direction in FIG. 9.
Specifically, similar to left-side roof beam 7 illustrated in FIG.
9, right-side roof beam 8 has a pipe structure and the pipe has a
sectional shape of a deformed pipe. Similar to left-side member 17
illustrated in FIG. 9, right-side member 18 is welded on and fixed
integrally to right-side roof beam 8, and the upper surface thereof
is configured to be higher than the upper surface of roof plate 2
in the vertical direction.
[0057] With reference to FIG. 10, roof plate 2 is fixed directly on
the upper surfaces of width-direction roof beam 9a and right-side
roof beam 8. Width-direction roof beam 9a has a pipe structure
which has a hollow space inside and the pipe is a deformed pipe
having a sectional shape which is non-circular but bent and
complicated. Thereby, width-direction roof beam 9a has a section
stiffness stronger than roof plate 2. Width-direction member 19 is
welded on the upper surface of width-direction roof beam 9a, and
thereby, width-direction member 19 is fixed integral to
width-direction roof beam 9a. Width-direction member 19 is disposed
to protrude upward relative to the upper surface of width-direction
roof beam 9a. Width-direction member 19 is fixed directly on
width-direction roof beam 9a at a position on the surface of
width-direction roof beam 9a without overlapping with roof plate 2.
Width-direction member 19 is disposed rearward to the rear edge of
roof plate 2. The upper surface of width-direction member 19 is
configured to be higher than the upper surface of roof plate 2 in
the vertical direction.
[0058] With reference to FIG. 11, second mount member 20 includes
top plate 21 described above. Top plate 21 has a rectangle shape in
planar view. The plate forming top plate 21 is bent at each side of
the rectangle to form fin-shaped portions 22. Fin-shaped portion 22
forms an outer circumferential surface of second mount member 20.
Second mount member 20 further includes a lateral pair of vertical
support members 23 extending in the anteroposterior direction of
cab 1 and a plurality of horizontal support members 24 extending in
the lateral direction of cab 1. Vertical support members 23 and
horizontal support members 24 are assembled to form an integral
frame structure, and top plate 21 is mounted on the frame
structure.
[0059] The paired vertical support members 23 are mounted on
left-side member 17 and right-side member 18, respectively. Holes
25 are formed to penetrate both top plate 21 and vertical support
members 23, and as described above, top plate 21 and vertical
support members 23 are fixed to left-side member 17 and right-side
member 18 through bolts.
[0060] Horizontal support members 24 include a horizontal support
member 24a mounted on width-direction member 19. Holes 26 are
formed to penetrate both top plate 21 and horizontal support member
24a, and as described above, top plate 21 and horizontal support
member 24a are fixed to width-direction member 19 through
bolts.
[0061] Horizontal support members 24 are provided in the same
number as that of holes 25 formed in vertical support members 23.
Horizontal support members 24 are installed to vertical support
members 23 at positions where holes 25 are formed in vertical
support member 23. The plurality of horizontal support members 24
are arranged with an equal interval between each other in the
anteroposterior direction of cab 1.
[0062] Hereinafter, the effects of the present embodiment will be
described.
[0063] In the present embodiment, as illustrated in FIG. 5,
positioning antenna 50 is disposed above roof plate 2 of cab 1. The
disposition of positioning antenna 50 on the roof portion of cab 1
enables positioning antenna 50 to be easily disposed at the highest
position in bulldozer 30, which thereby improves the positioning
accuracy of the present position of the work implement by means of
positioning antenna 50.
[0064] Cab 1 as a whole is mounted on the main body of the work
vehicle with a vibration absorber interposed therebetween to absorb
vibrations, and thereby, the vibrations transferred to the
structural materials of cab 1 can be suppressed. Accordingly, it is
possible to prevent positioning antenna 50 itself from vibrating,
which thereby prevents the positioning accuracy from being
decreased by vibrations, and as a result, it is possible to further
improve the positioning accuracy of positioning antenna 50 and
prevent positioning antenna 50 from damage as well.
[0065] Positioning antenna 50 is mounted on the roof portion of cab
1 with first mount member 10 and second mount member 20 interposed
therebetween. First mount member 10 includes left-side member 17
fixed on left-side roof beam 7 and right-side member 18 fixed on
right-side roof beam 8. Left-side roof beam 7 and right-side roof
beam 8 are welded together to form a rigid structure body for the
roof of cab 1. Left-side roof beam 7 and right-side roof beam 8 are
also a part of the rollover protection structure of cab 1, which
means they are forming a rigid structure at this point of view.
[0066] Second mount member 20 is disposed above roof plate 2 across
left-side member 17 and right-side member 18, and positioning
antenna 50 is installed on second mount member 20, and thereby,
positioning antenna 50 is supported by the roof beams which is a
rigid structure. Accordingly, it is possible to prevent the
position of positioning antenna 50 from being varied by the
vibrations of roof plate 2, which makes it possible to locate
positioning antenna 50 accurately relative to the structural
materials of cab 1. Thereby, it is possible to install positioning
antenna 50 above roof plate 2 at an accurate position and in a
proper attitude, improving the positioning accuracy of positioning
antenna 50 and the reliability of positioning antenna 50.
[0067] In the present embodiment as illustrated in FIG. 4, it is
acceptable that roof plate 2 is convexly curved upward. By forming
roof plate 2 into a convex structure, it is possible to prevent
water from being accumulated on upper surface 2a of roof plate 2.
Since positioning antenna 50 is installed above roof plate 2
through the intermediary of first mount member 10 and second mount
member 20, it is possible to prevent the convexly curving shape of
roof plate 2 from interfering with the disposition of positioning
antenna 50. Thereby, positioning antenna 50 can be installed above
roof plate 2 at an accurate position and in a proper attitude with
more certainty.
[0068] As illustrated in FIG. 8, it is acceptable that gap G is
formed between second mount member 20 and roof plate 2. Thereby, it
is possible to prevent with more certainty the vibrations of roof
plate 2 from affecting the position of positioning antenna 50,
which makes it possible to install positioning antenna 50 above
roof plate 2 at an accurate position with more certainty. Even
though roof plate 2 is formed into a convex shape, second mount
member 20 is disposed without contacting roof plate 2, and thereby,
it is possible to prevent roof plate 2 from interfering with second
mount member 20. Accordingly, it is possible to install positioning
antenna 50 on second mount member 20 in more proper attitude.
[0069] It is acceptable that a part of antenna cable 56 connected
to positioning antenna 50 is disposed in gap G between second mount
member 20 and roof plate 2. Thereby, antenna cable 56 can be
protected by second mount member 20 from the outer environment,
improving operation life of antenna cable 56. Moreover, since a
part of antenna cable 56 is disposed below second mount member 20,
the part of antenna cable 56 covered by second mount member 20 is
invisible from the outside. Thereby, it is possible to make the
outer appearance of the work vehicle look better.
[0070] In gap G, antenna cable 56 is retained to the side of rear
surface 21b of top plate 21 of second mount member 20. Thereby, it
is possible to prevent antenna cable 56 from being shaken to
collide with roof plate 2 or horizontal support member 24 or the
like at times when the work vehicle is moving or similar
situations, which makes it possible to improve reliability of
antenna cable 56.
[0071] As illustrated in FIG. 7, it is acceptable that left-side
member 17 and right-side member 18 are welded on the upper surfaces
of left-side roof beam 7 and right-side roof beam 8, respectively.
Since left-side roof beam 7 and right-side roof beam 8 are
structural materials constituting cab 1, in order to prevent the
strength of cab 1 itself from being decreased, it is required to
keep the strength of left-side roof beam 7 and right-side roof beam
8. Fixing left-side member 17 and right-side member 18 through
welding saves the need of performing additional processing on
left-side roof beam 7 and right-side roof beam 8 in order to fix
left-side member 17 and right-side member 18. Thereby, it is
possible to keep the strength of left-side roof beam 7 and
right-side roof beam 8, preventing the strength of cab 1 from being
decreased with certainty.
[0072] The term "welding" mentioned above refers to any processing
by which it is possible to integrate left-side member 17 and
right-side member 18 with the upper surfaces of left-side roof beam
7 and right-side roof beam 8, respectively, without decreasing the
strength of left-side roof beam 7 and right-side roof beam 8.
Thereby, the term is not limited to welding in narrow definition
that heat and/or pressure are applied to at least one of left-side
member 17 and left-side roof beam 7 to join the two through
welding. In other words, it is acceptable to join left-side member
17 and left-side roof beam 7 through the use of a filler material
or through pressure welding or soldering.
[0073] Screw tap holes 15 are formed in left-side member 17 and
right-side member 18 included in first mount member 10 to a depth
not penetrating left-side member 17 and right-side member 18 in the
vertical direction thereof and thereby to have a bottom, and second
mount member 20 is fixed to first mount member 10 through
bolt-screwing. Thereby, it is possible to prevent such processing
as perforating holes or the like in left-side roof beam 7 and
right-side roof beam 8 so as to install second mount member 20,
which thereby keeps the strength of left-side roof beam 7 and
right-side roof beam 8 with more certainty.
[0074] As illustrated in FIG. 7, it is acceptable that
width-direction roof beam 9a or 9b is disposed on the top of cab 1,
extending in the lateral direction, and width-direction member 19
is fixed on width-direction roof beam 9a or 9b so as to support
second mount member 20. Thereby, second mount member 20 is
supported not only by left-side member 17 and right-side member 18
but also by width-direction member 19 extending in the lateral
direction of cab 1. Since first mount member 10 becomes a more
rigid structure, it is possible for first mount member 10 to
support second mount member 20 more stably. Consequently, it is
possible to have second mount member 20 disposed above roof plate 2
more stably.
[0075] As illustrated in FIG. 8, it is acceptable that second mount
member 20 includes antenna installation surface 21a having a planar
shape and positioning antenna 50 is mounted on antenna installation
surface 21a. Thereby, positioning antenna 50 is installed on a flat
plane, which makes it easier to mount positioning antenna 50 on
antenna installation surface 21a at an accurate position and in a
proper attitude.
[0076] As illustrated in FIG. 11, second mount member 20 includes
the lateral pair of vertical support members 23 extending in the
anteroposterior direction of cab 1 and the plurality of horizontal
support members 24 extending in the lateral direction of cab 1 for
joining the pair of vertical support members 23. Thereby, the
strength of second mount member 20 is improved. Second mount member
20 is configured to have a rigidity sufficient enough to prevent
flexure from occurring when it is disposed across left-side member
17 and right-side member 18. Thereby, it is possible to prevent
with certainty second mount member 20 from deformation by curving
downward to interfere with roof plate 2, further enabling
positioning antenna 50 to be mounted above roof plate 2 at an
accurate position and in a proper attitude.
[0077] If the rigidity of second mount member 20 is small, when
bulldozer 30 is in traveling or in operation through using dozing
blade 38, second mount member 20 may vibrate. The vibrations of
second mount member 20 will fluctuate the position of positioning
antenna 50 mounted on second mount member 20, and as a result,
positioning antenna 50 is deviated from an initially calibrated
position, which decreases the positioning accuracy of positioning
antenna 50 in determining the present position of the work
implement. Thus, as illustrated in FIG. 11, second mount member 20
is reinforced by the plurality of horizontal support members 24. As
a result, it is possible to improve the rigidity of second mount
member 20, preventing second mount member 20 from vibrating, and
thereby, it is possible to prevent positioning antenna 50 mounted
on second mount member 20 from vibrating, making it possible to
improve the positioning accuracy of positioning antenna 50.
[0078] In the above embodiment, each of left-side member 17 and
right-side member 18 is formed into a single member extending in
the anteroposterior direction of cab 1; however, it is acceptable
that each of left-side member 17 and right-side member 18 is formed
from a plurality of members being separated with an interval in the
anteroposterior direction of cab 1. Similarly, it is acceptable
that width-direction member 19 is formed from a plurality of
members being separated with an interval in the width direction of
cab 1. The disposition of intervals can prevent first mount member
10 from damming rain water flowing from the central portion of roof
plate 2 toward the edges thereof, making it less likely that water
is accumulated on roof plate 2. However, fixing a plurality of
members on the roof beam reduces the working efficiency of fixing
first mount member 10, and the disposition of intervals decreases
the strength of first mount member 10. In consideration of these
facts, it is preferred to optimize the design of first mount member
10.
[0079] In the above embodiment, welding is described as an example
of preferable approaches for fixing first mount member 10 on the
roof beam; however, the fixing approach is not limited thereto. In
the case that it is possible to prevent the strength of the roof
beam from being decreased and keep the fixed strength of first
mount member 10 to the roof beam sufficient, it is acceptable to
adopt any other approach such as adhesion or the like to fix first
mount member 10 to the roof beam.
[0080] In the above embodiment, although it is described that
width-direction member 19 is disposed at the rear side of cab 1 and
the rear edge of second mount member 20 is supported by
width-direction member 19, it is acceptable to dispose
width-direction member 19 at an arbitrary position in the
anteroposterior direction of cab 1. For example, it is acceptable
to dispose a width-direction member to support the front edge of
second mount member 20, it is acceptable to dispose the
width-direction member to support a middle portion of second mount
member 20 in the anteroposterior direction, and it is also
acceptable to dispose a plurality of width-direction members.
[0081] It is possible to support second mount member 20 more stably
on first mount member 10 by inserting a bolt through horizontal
support member 24 configured to improve the rigidity of second
mount member 20 to fix second mount member 20 on width-direction
member 19. In this regard, it is preferable to optimize the designs
of first mount member 10 and second mount member 20 so as to
dispose width-direction members 19 and horizontal support members
24 overlapping each other at positions in the anteroposterior
direction of cab 1.
[0082] If second mount member 20 is offered with a sufficiently
great rigidity, it is possible that second mount member 20 will not
flex even when the lateral edges thereof are supported by left-side
member 17 and right-side member 18 respectively. In this case, the
width-direction member disposed on the roof beam of cab 1 may be
omitted.
[0083] In the above embodiment, bulldozer 30 is described as an
example of the work vehicle; however, the work vehicle of the
present invention is not limited to a bulldozer, and it may be
another work vehicle such as a wheel loader, a motor grader or the
like.
[0084] It should be understood that the embodiments disclosed
herein have been presented for the purpose of illustration and
description but not limited in all aspects. It is intended that the
scope of the present invention is not limited to the description
above but defined by the scope of the claims and encompasses all
modifications equivalent in meaning and scope to the claims.
REFERENCE SIGNS LIST
[0085] 1: cab; 2: roof plate; 2a: upper surface; 2b: lower surface;
7: left-side roof beam; 8: right-side roof beam; 9a, 9b:
width-direction roof beam; 10: first mount member; 15, 16: screw
tap hole; 17: left-side member; 18: right-side member; 19:
width-direction member; 20: second mount member; 21: top plate;
21a: antenna installation surface; 21b: rear surface; 22:
fin-shaped portion; 23: vertical support member; 24, 24a:
horizontal support member; 25, 26: hole; 27, 29: through hole; 28:
antenna cable outdrawing member; 30: bulldozer; 38: dozing blade;
50: positioning antenna; 51: antenna main body; 52: support member;
56: antenna cable; G: gap; OP: operator
* * * * *