U.S. patent application number 09/778078 was filed with the patent office on 2001-06-28 for operator's cab in construction machine.
This patent application is currently assigned to HITACHI CONSTRUCTION MACHINERY CO., LTD.. Invention is credited to Hirata, Toichi, Nakagawa, Takashi, Sakyo, Tsuyoshi, Sonoda, Jun, Tamura, Kazuhisa.
Application Number | 20010005092 09/778078 |
Document ID | / |
Family ID | 18277680 |
Filed Date | 2001-06-28 |
United States Patent
Application |
20010005092 |
Kind Code |
A1 |
Sakyo, Tsuyoshi ; et
al. |
June 28, 2001 |
Operator's cab in construction machine
Abstract
An operator's cab in a construction machine in which hollow
pillar portions are formed each with an outer panel and an inner
panel bonded to each other and the hollow pillar portions
constitute an operator's cab frame, includes at least one
reinforcement member constituted of thin plate that is bonded to
the outer panel and/or the inner panel to divide an internal space
of each of the hollow pillar portions.
Inventors: |
Sakyo, Tsuyoshi;
(Niihari-gun, JP) ; Hirata, Toichi; (Ushiku-shi,
JP) ; Tamura, Kazuhisa; (Ishioka-shi, JP) ;
Sonoda, Jun; (Abiko-shi, JP) ; Nakagawa, Takashi;
(Niihari-gun, JP) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
Alexandria
VA
22320
US
|
Assignee: |
HITACHI CONSTRUCTION MACHINERY CO.,
LTD.
|
Family ID: |
18277680 |
Appl. No.: |
09/778078 |
Filed: |
February 7, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09778078 |
Feb 7, 2001 |
|
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09203666 |
Dec 1, 1998 |
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6209949 |
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Current U.S.
Class: |
296/190.08 ;
296/190.03; 296/203.02; 296/203.03; 296/203.04 |
Current CPC
Class: |
B62D 27/026 20130101;
B62D 21/09 20130101; B62D 33/06 20130101 |
Class at
Publication: |
296/190.08 ;
296/190.03; 296/203.02; 296/203.03; 296/203.04 |
International
Class: |
B60R 027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 4, 1997 |
JP |
9-334463 |
Claims
What is claimed is:
1. An operator's cab in a construction machine in which hollow
pillar portions are formed each with an outer panel and an inner
panel bonded to each other and the hollow pillar portions
constitute an operator's cab frame, comprising: at least one
reinforcement member constituted of thin plate that is bonded to
said outer panel and/or said inner panel to divide an internal
space of each of said hollow pillar portions.
2. An operator's cab in a construction machine according to claim
1, wherein a modulus of section in each of said hollow pillar
portions is gradually increased toward a bottom surface of said
operator's cab frame to lessen bending stress at said hollow pillar
portion.
3. An operator's cab in a construction machine according to claim
1, wherein said reinforcement member is bonded to a base plate
constituting a bottom portion of said operator's cab.
4. An operator's cab in a construction machine according to claim
1, wherein said reinforcement member is distanced from a base plate
constituting a bottom portion of said operator's cab.
5. An operator's cab in a construction machine according to claim
1, wherein said hollow pillar portions are each constituted of
elongated space and said reinforcement member is provided along a
direction of length of said elongated space.
6. An operator's cab in a construction machine according to claim
1, wherein said hollow pillar portions are provided at, at least,
one set of left and right ends among left and right ends at a front
surface of said operator's cab, left and right ends at a rear
surface of said operator's cab and left and right ends in a middle
area located between said left and right ends at said front surface
and said left and right ends at said rear surface of said
operator's cab.
7. An operator's cab in a construction machine according to claim
1, wherein a cross sectional shape of said reinforcement member has
a roughly square bracket shape.
8. An operator's cab in a construction machine in which hollow
pillar portions are formed each with an outer panel and an inner
panel bonded to each other and the hollow pillar portions
constitute an operator's cab frame, comprising: at least one
reinforcement member constituted of thin plate that is bonded to an
outer side of each hollow pillar portion to form a hollow portion
outside said internal space of said hollow pillar portion.
9. An operator's cab in a construction machine according to claim
8, wherein a cross sectional shape of said reinforcement member has
a roughly square bracket shape.
10. An operator's cab in a construction machine in which hollow
pillar portions are formed each with an outer panel and an inner
panel bonded to each other and the hollow pillar portions
constitute an operator's cab frame, comprising: mid hollow pillar
portions that are provided at left and right ends in a middle area
located between a front surface and a rear surface of said
operator's cab; and a reinforcement member that is provided at each
of said mid hollow pillar portions.
11. An operator's cab in a construction machine according to claim
10, wherein said reinforcement member is constituted of thin
plate.
12. An operator's cab in a construction machine according to claim
11, wherein a cross sectional shape of said reinforcement member
has a roughly square bracket shape.
13. An operator's cab in a construction machine in which hollow
pillar portions are formed each with an outer panel and an inner
panel bonded to each other and the hollow pillar portions and a
roof which is provided above the hollow pillar portions constitute
an operator's cab frame, comprising: a roof reinforcement member
that extends left and right in said operator's cab and is bonded to
said roof to form a hollow portion between said roof reinforcement
member and said roof.
14. An operator's cab in a construction machine according to claim
13, further comprising a pillar reinforcement member at said hollow
pillar portion.
15. An operator's cab in a construction machine according to claim
14, wherein said pillar reinforcement member and said roof
reinforcement member are bonded to form an integrated
structure.
16. An operator's cab in a construction machine according to claim
13, wherein said roof reinforcement member is constituted of thin
plate.
17. An operator's cab in a construction machine according to claim
16, wherein a cross sectional shape of said roof reinforcement
member has a roughly square bracket shape.
18. An operator's cab in a construction machine according to claim
13, wherein: said hollow pillar portions are provided at, at least,
one set of left and right ends among left and right ends at a front
surface, left and right ends at a rear surface and left and right
ends in a middle area located between said left and right ends at
said front surface and said left and right ends at said rear
surface of said operator's cab and said roof reinforcement member
is mounted laterally between upper ends of a pair of said hollow
pillar portions.
19. An operator's cab in a construction machine according to claim
18, further comprising a pillar reinforcement member at said hollow
pillar portion.
20. An operator's cab in a construction machine according to claim
19, wherein said pillar reinforcement member and said roof
reinforcement member are bonded to form an integrated structure.
Description
INCORPORATION BY REFERENCE
[0001] The disclosures of the following priority applications are
herein incorporated by reference:
[0002] Japanese Patent Application No. 9-334463 filed Dec. 4,
1997.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to an operator's cab (room) in
a construction machine such as a hydraulic shovel, a wheel loader
or the like.
[0005] 2. Description of the Related Art
[0006] Safety in construction machines has been pursued with
increasing vigor in recent years, and various standards have been
set forth in order to protect operators or passengers inside the
operator's cab by hypothesizing various conditions that may occur
during operation at a construction site, such as, for instance, an
object falling from above, an object flying from the front, or the
machine tipping over. One of such standards, the TOPS (tipping over
protective structure) specifies that when the machine body tips
over and the tipping load is placed on the upper portion of the
side surfaces of the operator's cab of a hydraulic shovel resulting
in the frame that constitutes the operator's cab becoming deformed,
the deformed member be prevented from entering the vicinity of the
operator's seat provided inside the operator's cab from the
viewpoint of operator or passenger protection.
[0007] The structures adopted for operator's cabs of hydraulic
shovels in the prior art include one that is constituted by bonding
an inner panel provided toward the operator's cab and an outer
panel provided on the outside of the inner panel, and further
distending a portion of the inner panel and a portion of the outer
panel inward and outward respectively relative to the operator's
cab to form hollow pillar portions. In order to satisfy the need
for improving the strength of the operator's cab in an operator's
cab structure such as this provided with pillar portions,
reinforcement member constituted of steel pipe or steel bar may be
inserted inside the hollow pillar portions to improve the strength
against a tipping load, as disclosed in, for instance, Japanese
Laid-open Patent Publication No. Heisei-9-25648.
[0008] However, when a commercially available product such as a
steel pipe or a steel bar is used as a reinforcement member to be
inserted inside a hollow pillar portion, the size of the steel pipe
or the steel bar to be used is subject to restriction imposed by
the shape of the pillar if the reinforcement member is to be
inserted while maintaining the existing pillar shape, and thus, it
is difficult to achieve an optimal shape for the pillar portion in
terms of strength. In addition, if the pillar shape is changed to
accommodate the steel pipe or the steel bar, it will lead to a
major design modification and an increase in the production
cost.
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide an
operator's cab in a construction machine whose strength can be
improved effectively without having to greatly change the shape of
pillars in an existing operator's cab.
[0010] In order to attain the above object, an operator's cab in a
construction machine according to the present invention in which
hollow pillar portions are formed each with an outer panel and an
inner panel bonded to each other and the hollow pillar portions
constitute an operator's cab frame, comprises: at least one
reinforcement member constituted of thin plate that is bonded to
the outer panel and/or the inner panel to divide an internal space
of each of the hollow pillar portions.
[0011] In this operator's cab in a construction machine,
preferably, a modulus of section in each of the hollow pillar
portions is gradually increased toward a bottom surface of the
operator's cab frame to lessen bending stress at the hollow pillar
portion.
[0012] Also, preferably, the reinforcement member is bonded to a
base plate constituting a bottom portion of the operator's cab.
[0013] Also, the reinforcement member can be distanced from a base
plate constituting a bottom portion of the operator's cab.
[0014] Also, preferably, the hollow pillar portions are each
constituted of elongated space and the reinforcement member is
provided along a direction of length of the elongated space.
[0015] Also, preferably, the hollow pillar portions are provided
at, at least, one set of left and right ends among left and right
ends at a front surface of the operator's cab, left and right ends
at a rear surface of the operator's cab and left and right ends in
a middle area located between the left and right ends at the front
surface and the left and right ends at the rear surface of the
operator's cab.
[0016] Also, preferably, a cross sectional shape of the
reinforcement member has a roughly square bracket shape.
[0017] Another operator's cab in a construction machine according
to the present invention in which hollow pillar portions are formed
each with an outer panel and an inner panel bonded to each other
and the hollow pillar portions constitute an operator's cab frame,
comprises: at least one reinforcement member constituted of thin
plate that is bonded to an outer side of each hollow pillar portion
to form a hollow portion outside the internal space of the hollow
pillar portion.
[0018] In this operator's cab in a construction machine,
preferably, a cross sectional shape of the reinforcement member has
a roughly square bracket shape, too.
[0019] Another operator's cab in a construction machine according
to the present invention in which hollow pillar portions are formed
each with an outer panel and an inner panel bonded to each other
and the hollow pillar portions constitute an operator's cab frame,
comprises: mid hollow pillar portions that are provided at left and
right ends in a middle area located between a front surface and a
rear surface of the operator's cab; and a reinforcement member that
is provided at each of the mid hollow pillar portions.
[0020] In this operator's cab in a construction machine,
preferably, the reinforcement member is constituted of thin plate
and furthermore a cross sectional shape of the reinforcement member
has a roughly square bracket shape, too.
[0021] Another operator's cab in a construction machine according
to the present invention in which hollow pillar portions are formed
each with an outer panel and an inner panel bonded to each other
and the hollow pillar portions and a roof which is provided above
the hollow pillar portions constitute an operator's cab frame,
comprises: a roof reinforcement member that extends left and right
in the operator's cab and is bonded to the roof to form a hollow
portion between the roof reinforcement member and the roof.
[0022] This operator's cab in a construction machine, preferably,
further comprises a pillar reinforcement member at the hollow
pillar portion. Furthermore, preferably, the pillar reinforcement
member and the roof reinforcement member are bonded to form an
integrated structure.
[0023] In this operator's cab in a construction machine,
preferably, the roof reinforcement member is constituted of thin
plate and furthermore a cross sectional shape of the roof
reinforcement member has a roughly square bracket shape, too. Also,
preferably, the hollow pillar portions are provided at, at least,
one set of left and right ends among left and right ends at a front
surface, left and right ends at a rear surface and left and right
ends in a middle area located between the left and right ends at
the front surface and the left and right ends at the rear surface
of the operator's cab and the roof reinforcement member is mounted
laterally between upper ends of a pair of the hollow pillar
portions. Further, preferably, this operator's cab in a
construction machine comprises a pillar reinforcement member at the
hollow pillar portion. Also, preferably, the pillar reinforcement
member and the roof reinforcement member are bonded to form an
integrated structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 shows a perspective view illustrating the frame
structure of the operator's cab of a hydraulic shovel.
[0025] FIG. 2 shows a cross section of the operator's cab in an
embodiment of the present invention along the horizontal
direction.
[0026] FIG. 3 shows a cross section of a first pillar in the
embodiment along the horizontal direction.
[0027] FIG. 4 shows a cross section of a second pillar in the
embodiment along the horizontal direction.
[0028] FIG. 5 shows a cross section of a third pillar in the
embodiment along the horizontal direction
[0029] FIG. 6 shows a cross section of the second pillar in the
embodiment along the vertical direction.
[0030] FIG. 7 shows a cross section of a side of the roof portion
above the second pillar in the embodiment.
[0031] FIG. 8 shows a perspective view illustrating the bonding of
a longitudinal reinforcement member and a lateral reinforcement
member in the embodiment.
[0032] FIG. 9 shows the relationship between the tipping load
applied to a side surface of the operator's cab and
displacement.
[0033] FIG. 10 shows a cross section of a first pillar along the
horizontal direction in an example of a variation of the
embodiment.
[0034] FIG. 11 shows a cross section of a first pillar along the
horizontal direction in another example of a variation of the
embodiment.
[0035] FIG. 12 shows a cross section of a first pillar along the
horizontal direction in yet another example of a variation of the
embodiment.
[0036] FIG. 13 shows a cross section of a first pillar along the
horizontal direction in yet another example of a variation of the
embodiment.
[0037] FIG. 14 shows a cross section of a first pillar along the
horizontal direction in yet another example of a variation of the
embodiment.
[0038] FIG. 15 shows a cross section of a second pillar along the
vertical direction in an example of a variation of the
embodiment.
[0039] FIG. 16 shows a cross section the upper portion of the
second pillar along the vertical direction in an example of a
variation of the embodiment.
[0040] FIG. 17 shows the frame structure in an example of a
variation of the operator's cab in the embodiment
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] The following is an explanation of the embodiment of the
present invention in reference to the drawings.
[0042] FIG. 1 is a perspective view illustrating the frame
structure of the operator's cab in an embodiment of the present
invention and FIG. 2 is a cross section along line II-II in FIG. 1.
As illustrated in FIG. 2, the left side surface and the right side
surface of the operator's cab 1 are each constituted of a pair of
panels, i.e., an inner panel 7 and an outer panel 8, whereas the
front surface and the rear surface of the operator's cab 1 are
respectively constituted of a front panel 9 and a rear panel 10.
The inner panel 7 and the outer panel 8 are bonded to overlap each
other, and hollow (or empty) pillar portions are formed between the
inner panel 7 and the outer panel 8 at the frontmost portion, the
rearmost portion and the middle portion located between them, of
the operator's cab 1. These pillar portions are referred to as
first pillars 3A and 3B, second pillars 4A and 4B and third pillars
5A and 5B from the front to the rear, and first reinforcement
members 30, 40 and 50 that are to be detailed later are provided
inside the individual pillars 3A and 3B through 5A and 5B.
[0043] As illustrated in FIG. 1, the bottom surface of the
operator's cab 1 is formed with a base plate 2, and the first
pillars 3A and 3B through third pillars 5A and 5B are provided
standing erect on the base plate 2. The top surface of the
operator's cab 1 is constituted of a roof 6 provided at the upper
ends of the pillars 3A and 3B through 5A and 5B. Thus, the
operator's cab frame FR constituting the main frame structure of
the operator's cab 1 is constituted of the individual surfaces at
the front, at the rear, at the left, at the right, at the top and
at the bottom to achieve a roughly rectangular parallelopiped. At
the front surface and the rear surface of the operator's cab frame
FR, an opening FH for mounting a front glass and an opening RH for
mounting a rear glass are provided respectively, with an opening WH
for mounting a window provided at both the left side surface and
the right side surface of the frame FR. An opening DH for mounting
a door is provided at the left side surface of the frame FR, and an
opening TH for mounting a skylight is provided at the front side of
the roof 6.
[0044] Next, the shapes of the pillars in this embodiment are
explained in reference to FIGS. 3 through 5 that are enlargements
of the first pillar 3A, the second pillar 4A and the third pillar
5A in FIG. 2. As illustrated in FIG. 3, the first pillar portion 3A
is provided with a hollow portion 3C between the inner panel 7 and
the outer panel 8 having cross sections achieving rough "]" shapes
(Square bracket or Japanese letter "]" shape) facing opposite each
other and distended inward and outward respectively, and the front
and rear portions of the inner panel 7 and the outer panel 8 are
bonded with each other one on top of the other. At the hollow
portion 3C, a longitudinal reinforcement plate 30 with its cross
section achieving a rough "]" shape to face opposite the inner
panel 7 is provided and the inner surface of the longitudinal
reinforcement plate 30 in the back and forth direction of the
operator's cab is bonded to the inner surface of the inner panel 7
at two locations that are distanced from each other to divide the
hollow portion 3C into two portions. An end of the front panel 9,
with its cross section achieving an L shape, is bonded to the inner
surface of the inner panel 7 at the bonding area of the inner panel
7 and the outer panel 8 toward the front. The longitudinal
reinforcement member 30 is formed by press-processing a thin
plate.
[0045] As illustrated in FIG. 4, the second pillar portion 4A, too,
is provided with a hollow portion 4C between the inner panel 7 and
the outer panel 8 having cross sections formed in rough "]" shapes
facing opposite each other, as in the case with the first pillar
portion 3A. At the hollow portion 4C, a longitudinal reinforcement
plate 40 with its cross section achieving a rough "]" shape to face
opposite the outer panel 8 is provided and the outer surface of the
longitudinal reinforcement plate 40 in the back and forth direction
of the operator's cab is bonded to the inner surface of the outer
panel 8 at two locations that are distanced from each other to
divide the hollow portion 3C into two portions. The longitudinal
reinforcement member 40 is formed by press-processing a thin
plate.
[0046] As illustrated in FIG. 5, the third pillar portion 5A, too,
is provided with a hollow portion 5C between the inner panel 7 and
the outer panel 8 having cross sections formed in rough "]" shapes
facing opposite each other, as in the case with the first pillar
portion 3A. At the hollow portion 5C, a longitudinal reinforcement
plate 50 with its cross section achieving a rough "]" shape to face
opposite the outer panel 8 is provided and the outer surface of the
longitudinal reinforcement plate 50 in the back and forth direction
of the operator's cab is bonded to the inner surface of the outer
panel 8 at two locations that are distanced from each other to
divide the hollow portion 5C into two portions. An end of the rear
panel 10 having a cross section achieving an L shape is bonded to
the inner surface of the inner panel 7 at the bonding area of the
inner panel 7 and the outer panel 8 toward the rear. The
longitudinal reinforcement member 50 is formed by press-processing
a thin plate. It is to be noted that the individual pairs of pillar
portions 3A and 3B through 5A and 5B constituting part of the
operator's cab frame FR achieve left/right symmetry, and the pillar
portions 3B, 4B and 5B whose explanation is omitted here, too, are
provided with longitudinal reinforcement plates 30, 40 and 50
respectively as are the pillar portions 3A, 4A and 5A explained
above.
[0047] Next, the shapes of the longitudinal reinforcement plates
30, 40 and 50 in the vertical direction are explained in reference
to FIG. 6 which is a cross section along line VI-VI in FIG. 1 (a
cross section of the second pillar 4A along the vertical
direction). As illustrated in FIG. 6, the lower end of the outer
panel 8 is bonded to the outer surface of the base plate 2 having a
cross section achieving an L shape. The upper portion of the outer
panel 8 is bent toward the inside of the operator's cab 1 almost at
a right angle with the inner surface of a flange 8A provided at the
upper end bonded to the outer surface of the upper end 7A of the
inner panel 7. On the inside of the outer panel 8, the longitudinal
reinforcement member 40 mentioned earlier is provided parallel to
the outer panel 8, and the lower end of the longitudinal
reinforcement member 40 is bonded to the upper surface of the base
plate 2. The upper portion of the longitudinal reinforcement member
40 is bent toward the inside of the operator's cab 1 almost at a
right angle, with its front end passing through an opening portion
7B of the inner panel 7 opening in a shape that is the same as the
cross section of the longitudinal reinforcement plate 40 to be
bonded to the inner panel 7 at the opening portion 7B. The lower
end of the inner panel 7 is bonded to the upper surface of the base
plate 2, and a rail bend 7C for housing the front glass is provided
in the upper portion of the inner panel. Exactly the same structure
is assumed for the second pillar 4B.
[0048] As illustrated in FIG. 7, which is a cross section along
line VII-VII in FIG. 6, in the areas of the roof 6 where the upper
ends of the second pillars 4A and 4B are bonded, a distended
portion 6B extends to the left and right in the operator's cab. At
the inner surface of the roof 6, a lateral reinforcement member 60
having a cross section achieving a rough "]" shape to face opposite
the distended portion 6B, which extends to the left and right in
the operator's cab, is bonded to the roof 6 at two locations
distanced from each other in the back and forth direction of the
operator's cab to form a hollow portion 6C. In addition, as
illustrated in FIG. 6, a flange 6A is provided at the left end of
the roof 6 (at the right end in FIG. 6), with a side surface of the
flange 6A bonded to the inner surface of the upper end 7A of the
inner panel. As illustrated in FIG. 8, which is a perspective view
of the VIII area in FIG. 6, the left end of the lateral
reinforcement member 60 (the right end portion in FIG. 6) is
press-processed to achieve a staged shape (so-called joggled
processing) so that the right end of the longitudinal reinforcement
member 40 (the left end portion in FIG. 6) is fitted in and bonded
at the staged portion. It is to be noted that hollow portions 6C
constituted by distended portions 6B and lateral reinforcement
members 60 are provided in the areas of the roof 6 between the
first pillars 3A and 3B and between the third pillars 5A and 5B
that are not shown, as in the area between the second pillars 4A
and 4B. Since the reinforcement member is provided at the roof, the
rigidity in the upper portion of the operator's cab improves,
which, in turn, improves the strength against an object falling
from above. Also, since the pillar portions, the distended portion
and the lateral reinforcement member of the roof constitute
elongated space, the operator's cab achieves a so-called beam
structure, accordingly the strength of the operator's cab
effectively improved.
[0049] A tipping load F is applied to an X portion of the
operator's cab 1 at the left side (the second pillar 4A) in FIG. 1
and the relationship between the deformation quantity at the X
portion and the tipping load is illustrated in FIG. 9. In the
figure, the curve A represents the strength characteristics of an
operator's cab in the prior art that is not provided with
reinforcement members and the curve B represents the strength
characteristics of the operator's cab in the embodiment provided
with the reinforcement members 30, 40, 50 and 60. As illustrated in
FIG. 9, the strength of the operator's cab in the embodiment
demonstrates a great improvement over that in the prior art.
[0050] Thus, since the longitudinal reinforcement members 30, 40
and 50 and the lateral reinforcement members 60 constituted of thin
plate are provided at the pillars 3A and 3B through 5A and 5B and
the roof 6 of the operator's cab frame FR in the embodiment, the
strength of the operator's cab 1 can be improved effectively
without degrading of freedom in design that would otherwise result
if commercially available steel pipe or steel bar were employed to
constitute the reinforcement members. In addition, since the inner
panel 7 and the outer panel 8 in the prior art can be utilized as
is, no significant modification is required in the manufacturing
process and the increase in the production cost is minimized.
Furthermore, since the reinforcement members 30, 40, 50 and 60 are
provided only at the pillars 3A and 3B through 5A and 5B and the
roof 6 constituting the main frame of the operator's cab 1, the
increase in weight due to the use of the reinforcement members can
be minimized to ensure that the operating performance and the like
are not adversely affected.
[0051] While the shape of the longitudinal reinforcement member 30
provided at the first pillar 3A is illustrated in FIG. 3, the shape
of the reinforcement member 30 may be as illustrated in FIGS. 10
through 14, instead, and these alternatives are explained
below.
[0052] In FIG. 10, a longitudinal reinforcement member 31 with a
cross section achieving a roughly "]" shape is sandwiched and
clamped at the bonding areas of the inner panel 7 distended inward
and the outer panel 8 distended outward in the back and forth
direction of the operator's cab at two locations distanced from
each other. In FIG. 11, too, a longitudinal reinforcement member 32
is sandwiched and clamped at a bonding area of the inner panel 7
and the outer panel 8, as in FIG. 10. However, the shapes of the
inner panel 7 and the outer panel 8 at the front are different from
those in FIG. 10. By sandwiching and clamping the longitudinal
reinforcement member 31 or 32 between the inner panel 7 and the
outer panel 8, as illustrated in FIG. 10 or 11, the longitudinal
reinforcement member 31 or 32 can be concurrently bonded while
bonding the inner panel 7 and the outer panel 8 to achieve a
reduction in the number of steps for manufacturing the operator's
cab.
[0053] In FIG. 12, the rear end of a longitudinal reinforcement
member 33 is sandwiched and clamped at a bonding area of the inner
panel 7 and the outer panel 8, with its front end bonded to the
inner surface of the distended inner panel 7. Providing such a
longitudinal reinforcement member 33 will hide a bonding area of
the longitudinal reinforcement member 33 within the pillar to
achieve an esthetic improvement.
[0054] In FIG. 13, a longitudinal reinforcement member 34 is bonded
to the outer surface of the outer panel 8 to form another hollow
portion 3D adjacent to and outside of the hollow portion 3C
provided between the inner panel 7 and the outer panel 8. By
providing the longitudinal reinforcement member 34 at the outer
surface of the outer panel 8 in this manner, even the operator's
cab of an existing construction machine can be converted to achieve
a structure provided with reinforcement members easily.
[0055] In FIG. 14, the front and rear ends of longitudinal
reinforcement members 35 and 36 are bonded to the inner surface of
the inner panel 7 and the inner surface of the outer panel 8
respectively within the hollow portion 3C provided between the
inner panel 7 and the outer panel 8 to divide the hollow portion 3C
into three portions. By providing two longitudinal reinforcement
members 35 and 36 at the hollow portion 3C in this manner, the
modulus of section of the first pillar 3A is further increased to
provide a greater improvement in the strength of the operator's
cab.
[0056] It is to be noted that the shapes of the reinforcement
members 30, 40, 50 and 60 are not restricted to those adopted in
the embodiment, and any other shapes may be adopted for them as
long as they contribute to an improvement in the modulus of
section.
[0057] In addition, while the inner panel 7 and the longitudinal
reinforcement members 40 are positioned parallel to the outer panel
8 as illustrated in FIG. 6 in the embodiment, the positioning
arrangement is not limited to this and the lower portions of the
inner panel 7 and the longitudinal reinforcement members 40 may
curve toward the inside of the operator's cab, as illustrated in
FIG. 15, for instance. In other words, since the modulus of section
near the bottom surface of the operator's cab (the low portion of
the side surface of the operator's cab) is increased, any excessive
bending stress near the bottom surface will be suppressed. This
will further improve the flexural rigidity of the operator's cab
frame FR against the tipping load F applied to the upper portion of
the side surface of the operator's cab 1.
[0058] Furthermore, while the longitudinal reinforcement members
30, 40 and 50 and the lateral reinforcement member 60 are provided
in the operator's cab 1 in the embodiment described above, only the
longitudinal reinforcement members 30, 40 and 50 may be provided at
the pillar portions 3A and 3B through 5A and 5B, or as illustrated
in FIG. 16, which is a cross section of the upper portion of the
second pillar 4A along the vertical direction, only the lateral
reinforcement member 60 may be provided.
[0059] Moreover, as illustrated in FIG. 17, which presents a
perspective view of another frame structure for the operator's cab,
a roof guard 11 supported by the reinforcement members 30, 40, 50
and 60 of the pillars 3A and 3B through 5A and 5B may be provided
above the roof 6. This will further improve the rigidity of the
roof 6 and also a sufficient degree of strength can be achieved for
the operator's cab even against an object falling from above.
[0060] Also, while the longitudinal reinforcement members 30, 40
and 50 and the lateral reinforcement member 60 are mounted
continuously from the base plate 2 to the upper surface via the
side surfaces of the operator's cab 1 between the left and right in
the embodiment described above, they may be provided
non-continuously to be present intermittently only at locations
that need to be reinforced to ensure strength. Accordingly, the
base plate 2 and the longitudinal reinforcement members 30, 40 and
50 may not be bonded to each other and may be distanced from each
other. In addition, the inner panel 7, the outer panel 8, the
reinforcement members 30, 40, 50 and 60 and the like may be bonded
together through welding, brazing, adhesive, bolts, rivets or
bonded through any other method.
[0061] In the above embodiments, it is explained that the
longitudinal reinforcement members 30, 40 and 50 are provided in
the pillars 3A and 3B through 5A and 5B, respectively. However, all
pillars may not be provided with the longitudinal reinforcement
members, and only one of pairs of the pillars 3A and 3B through 5A
and 5B may be provided with the longitudinal reinforcement members,
or two of pairs of the pillars 3A and 3B through 5A and 5B may be
provided with the longitudinal reinforcement members. Since the
strength of the front surface of the operator's cab may be
maintained to the certain degree by the front panel 9 and the
strength of the rear surface of the operator's cab may be
maintained to the certain degree by the rear panel 10, only the mid
pillars 4A and 4B that do not have such a panel around there can be
provided with the longitudinal reinforcement members 40. By this
means, the strength of the operator's cab is effectively improved
with small amount of materials. Furthermore, since the strength of
the portion that is the closest to the operator is improved, safety
is effectively improved with small amount of materials or
members.
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