JP4086172B2 - Boom offset hydraulic excavator - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a boom offset hydraulic excavator used for side grooving and the like, and is particularly suitable for use in a small boom offset hydraulic excavator.
[0002]
[Prior art]
FIG. 4 is a side view showing a conventional boom offset hydraulic excavator. In the figure, 1 is a boom offset hydraulic excavator, 2 is an upper swing body, 3 is a lower traveling body, 4 is a cab that constitutes a cab, 5 is an offset boom, and 6 is a first boom that constitutes an offset boom. 7 is a second boom, 10 is a third boom, 11 is an arm, 12 is a bucket, 15 is a boom cylinder, 17 is an arm cylinder, and 18 is a bucket cylinder. FIG. 5 is a plan view of the boom offset hydraulic excavator shown in FIG. In the figure, 8 and 9 are second boom constituent members constituting the second boom 7, and 16 is an offset cylinder. 18 is a pivot shaft for pivotally supporting the second boom component member 8 on the first boom, 19 is a pivot shaft for pivotally supporting the second boom component member 9 on the first boom, and 20 is a second pivot component shaft for pivotally supporting the second boom component member 8. A pivot shaft 20 pivotally supports the third boom. A pivot shaft 20 pivotally supports the second boom component 9 on the third boom.
[0003]
According to the conventional boom offset hydraulic excavator 1 shown in FIGS. 4 and 5, the second boom constituent member 8 is maintained while the second boom constituent members 8 and 9 are maintained in parallel by operating the offset cylinder 16 to extend and contract. 9 swings in the left-right direction with respect to the first boom 6 and the third boom 10. As a result, the third boom 10, the arm 11, and the bucket 12 can be shifted in the left-right direction parallel to the first boom 6 in the front-rear direction center line. 12, the first boom 6 can be excavated parallel to the longitudinal center line.
[0004]
Further, according to the offset boom type hydraulic excavator shown in FIGS. 4 and 5, the position where the hydraulic piping to the offset cylinder 16, the arm cylinder 17 and the bucket cylinder 18 is sandwiched between the pair of left and right second boom constituent members 8 and 9. In addition to being good in appearance from the side, the offset cylinder 16 and the hydraulic piping are not brought into contact with external obstacles during work and are not damaged.
[0005]
Thereby, according to this type of hydraulic excavator, for example, a wall-side groove excavation when embedding a water pipe or the like can be easily performed without worrying about the contact of the offset cylinder 16 or the hydraulic piping. In particular, the swing of the second boom 7 to the opposite side of the cab 4 is easy to see the excavation state by the bucket 12 from the operator in the cab 4, and the amount of movement is set larger than the swing in the direction of the cab 4. In many cases, the outer side can be excavated by the width of the bucket 12 from the side of the lower traveling body 3.
[0006]
[Problems to be solved by the invention]
According to the boom offset hydraulic excavator shown in FIGS. 4 and 5, the tip of the first boom 6 has a shape that extends left and right toward the pivot shafts 18 and 19. This is because the larger the distance between the pivot shafts 18 and 19 (and the pivot shafts 20 and 21), the larger the offset amount. However, when the first boom 6 is raised and rotated by the boom cylinder 15, if the clearance S between the inner side surface of the cab 4 and the first boom 6 is not sufficiently taken, the vicinity of the front end of the first boom 6 and the cab 4. Will come into contact. For this reason, some conventional hydraulic excavators have avoided contact by sacrificing the living space by denting the ceiling of a cab or canopy (not shown).
[0007]
In particular, when such a structure is applied to a relatively small boom-offset hydraulic excavator, there is a significant problem that the cab space is restricted or the amount by which the boom is raised is restricted.
[0008]
[Means for Solving the Problems]
A driver's cab mounted on the upper swing body, a first boom connected to the upper swing body on the side of the driver's cab in a vertically swingable manner, and a left and right swing at the tip of the first boom. A second boom that is movably connected, a third boom that is swingably swingable in the left-right direction at the tip of the second boom, and a swinger that is swingable in the vertical direction at the tip of the third boom. Side gutter excavation having an arm and a work tool connected to the tip of the arm so as to be swingable in the vertical direction, and allowing the center line of the arm to swing in the horizontal direction parallel to the first boom. In the hydraulic excavator, the first boom is formed in a plane substantially parallel to a surface facing the operator cab on the side surface of the operator cab, and both the second boom is the first boom and the third boom. In addition to being swingably connected in the left-right direction A main boom member and a link rod member arranged in parallel, and the cab side surface of the main boom member is connected to the first boom in a state where the second boom is not rocked with respect to the first boom. The link rod member is positioned on substantially the same plane as the cab side surface, and the link rod member projects from the cab opposite side surface of the first boom, thereby swinging the second boom with respect to the first boom. In an unmoved state, the cab side surface of the first boom and the cab side surface of the second boom are positioned on substantially the same plane, and an offset cylinder for swinging the second boom is disposed on the main boom member. It is arranged on the side opposite to the cab and the second boom is not swung with respect to the first boom, and the longitudinal centerline of the third boom is located closer to the cab than the longitudinal centerline of the first boom. Is offset to the opposite side, so longitudinal center line is positioned in the arm on the longitudinal center line of the third boom, by connecting the arm to the third boom, the said second boom first The front-rear direction center line of the arm is offset to the opposite side of the cab from the front-rear direction center line of the first boom in a state where the boom is not swung .
[0009]
According to this, since the cab and the first boom do not come into contact with each other, the cab can be set up to a position close to the first boom, and the occupancy of the cab can be improved. In particular, in a small hydraulic excavator, it is possible to obtain a sufficient offset amount by increasing the amount of extension of the second boom to the opposite side of the cab while maintaining the occupancy of the cab. Further, the excavation position at the time of the maximum offset on the side opposite to the driver seat is separated from the first boom by offsetting the center line in the front and rear direction of the third boom to the side opposite to the driver seat from the center line in the front and rear direction of the first boom. Can be in a different position. Moreover, since the link rod side is positioned on the opposite side of the cab and is disposed so as to protrude, it is possible to increase the distance between the main boom member and the link rod member, and thereby to ensure a sufficient offset amount. it can.
[0010]
In addition, the third boom protrudes equally to the left and right with respect to the longitudinal center line of the arm, so that the third boom can be prevented from coming into contact with the groove wall surface during deep digging. Contact between the member and the wall surface of the link rod member can be prevented as much as possible.
[0011]
Furthermore, the main boom member and the link rod member are second boom constituent members having substantially the same shape arranged substantially symmetrically, and an offset cylinder for offset operation is arranged between the left and right second boom constituent members. In this case, the above-described operation can be obtained while the offset cylinder is not damaged by being brought into contact with an external obstacle.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view showing a boom offset hydraulic excavator 30 according to a first embodiment of the present invention. Reference numeral 31 is an upper swing body, 32 is a lower traveling body, 33 is a cab constituting a cab, 34 is a work attachment, 35 is a first boom, 36 is a second boom, and 37 is a main boom member constituting a second boom 36. , 38 is a link rod member constituting the second boom 36 , 39 is a third boom, 40 is an arm, 41 is a bucket, 42 is a center line in the front-rear direction of the first boom 35, 43 is the third boom 39 and the arm 40. A center line in the front-rear direction, 44 is an offset cylinder, 45 is an arm cylinder, 46 is a bucket cylinder, 47 is a pivot shaft that pivotally connects the first boom 35 and the main boom member 37 in the left-right direction, and 48 is a first boom. 35 and a pivot shaft for connecting the link rod member 38 so as to be swingable in the left-right direction. 49 is a pivot shaft for connecting the main boom member 37 and the third boom 39 so as to be swingable in the left-right direction. Link rod member 38 and a pivot shaft for pivotally connecting the third boom 39 in the lateral direction. FIG. 2 is a diagram illustrating a state in which the boom offset hydraulic excavator 30 in FIG. 1 has the arm offset.
[0013]
Based on FIG.1 and FIG.2, the structure and effect | action of the boom offset type hydraulic excavator of 1st Embodiment of this invention are described. According to the hydraulic excavator of the present embodiment, the upper swing body 31 is formed in a substantially circular shape and can be swung within the width of the lower traveling body 32. Further, the work attachment 34 extends and contracts the offset cylinder 44, so that the main boom member 37, the link rod member 38, the pivot shafts 47-48 of the first boom 35, and the third boom 39 are connected. The four-bar link formed between the pivot shafts 49-50 is deformed, and the longitudinal center line 43 of the arm 40 (and the third boom 39) is offset left and right with respect to the longitudinal center line 42 of the first boom 35. Can be moved. Thereby, it is possible to excavate within the range of the left and right offset amount of the arm 40 (B and C in FIG. 2) in parallel with the center line in the front-rear direction of the first boom 35. As a result, it is possible to easily excavate the side groove in the narrow space.
[0014]
A cab 33 constituting a cab is mounted on the side of the work attachment 34 of the upper swing body 31. In the small hydraulic excavator, the living space in the cab 33 is limited, but according to the present embodiment, the side surface of the first boom 35 on the cab 33 side is a plane substantially parallel to the cab side surface so as not to protrude in the cab direction. Therefore, there is no possibility of interfering with the cab 35 even if the first boom 35 is rotated in the upward direction. For this reason, the living space in a cab can be ensured to the maximum extent.
[0015]
For example, when the arm 40 is swung to the maximum offset position on either the left or right side, if the arm 40 is positioned in front of the cab 33, the arm 40, the third boom 39, and the second boom 36 are operators for the bucket 41 during excavation. The workability is poor. For this reason, the offset amount B of the arm 40 to the side opposite to the normal cab 33 is set large (B> A). Further, when excavating the side groove, as shown in FIG. 2, if the outer side can be excavated from the lower traveling body 32 by the approximate width of the bucket 41, there is no possibility that the bucket 41 contacts the lower traveling body 32 during the near excavation. The working range in the front-rear direction is widened. According to this embodiment, the position in which the front-rear direction center line 42 of the first boom 35 and the front-rear direction center line 43 of the arm 40 are offset by A to the opposite side of the cab 33 without swinging the second boom 36. Is arranged. For this reason, it is possible to excavate A (outside of B) by A from the offset amount (B-A) swung by the offset cylinder 44.
[0016]
Further, since the link rod member 38 side is positioned on the opposite side of the cab and is disposed so as to protrude, it is possible to increase the interval W between the main boom member 37 and the link rod member 38, thereby A sufficient amount of offset can be taken. Further, since the arm 40 is disposed at substantially the center position of the main boom member 37 and the link rod member 38, the third boom 39 projects in the right and left direction with respect to the center line 43 in the front-rear direction of the arm 40, thereby excavating the groove. It is possible to prevent the third boom 39 from coming into contact with the groove wall surface during deep digging, and to prevent the main boom member 37 and the link rod member 38 from contacting the wall surface as much as possible.
[0017]
FIG. 3 is a plan view showing a boom offset hydraulic excavator 60 showing a second embodiment of the present invention. In the figure, components having the same functions as those in the first embodiment are denoted by the same reference numerals. 61 is a work attachment, 62 is a second boom, 63 is a left second boom component corresponding to the main boom member in the first embodiment, and 64 is a right second boom corresponding to the link rod member of the first embodiment. The second boom constituent members 63 and 64 are a pair of left and right strength members and have a substantially symmetrical cross-sectional shape.
[0018]
According to the present embodiment, the hydraulic piping for the offset cylinder 44 and the arm cylinder 45 and the hydraulic piping for the bucket cylinder 46 are arranged between the second boom constituent members 63 and 64, so that they contact an external obstacle. Thus, the offset cylinder 44 and the hydraulic piping are not damaged. Moreover, since the offset cylinder 44 etc. are not exposed to the side, the beauty is good. Other operations are the same as in the first embodiment.
[0019]
Although only the cab specification hydraulic excavator has been described in the first embodiment and the second embodiment, the same applies to the case of a canopy specification that is mainly applied to a small hydraulic excavator.
[0020]
【The invention's effect】
According to the first aspect of the present invention, since the cab and the first boom do not come into contact with each other, the cab can be set up to a position close to the first boom, thereby improving the comfortability of the cab. be able to. In particular, in a small hydraulic excavator, it is possible to obtain a sufficient offset amount by increasing the amount of extension of the second boom to the opposite side of the cab while maintaining the occupancy of the cab. Further, the excavation position at the time of the maximum offset on the side opposite to the driver seat is moved away from the first boom by offsetting the center line in the front and rear direction of the third boom to the side opposite to the driver seat from the center line in the front and rear direction of the first boom. Can be in position. In addition, since the link rod side is positioned on the opposite side of the cab and is arranged so as to protrude, it is possible to increase the distance between the main boom member and the link rod member, thereby taking a sufficient offset amount. be able to.
[0021]
In addition, since the arm is arranged at substantially the center position of the main boom member and the link rod member, the third boom projects equally to the left and right with respect to the center line in the front-rear direction of the arm. It is possible to prevent the 3 boom from contacting the groove wall surface, and to prevent the main boom member and the link rod member from contacting the wall surface as much as possible.
[0022]
According to the third aspect of the present invention, in addition to the above-described effects, the above-described operation can be obtained while the offset cylinder is not damaged by being brought into contact with an external obstacle.
[0023]
As described above, according to the present invention, the occupant's occupancy space can be ensured to the maximum, and in particular, the working range on the side opposite to the cab can be increased from the longitudinal center line of the first boom. The comfort and workability can be improved.
[Brief description of the drawings]
FIG. 1 is a plan view showing a boom offset hydraulic excavator according to a first embodiment of the present invention.
2 is a diagram showing an offset swing state of the boom offset hydraulic excavator of FIG. 1; FIG.
FIG. 3 is a plan view showing a boom offset hydraulic excavator according to a second embodiment of the present invention.
FIG. 4 is a side view showing a boom offset hydraulic excavator according to an embodiment of the prior art.
5 is a plan view of the boom offset hydraulic excavator of FIG. 4. FIG.
[Explanation of symbols]
2, 31 Upper swing body 4, 33 Cab 5, 34, 61 Work attachment 6, 35 First boom 7, 36, 62 Second boom 37 Main boom member 38 Link rod member 10, 39 Third boom 11, 40 Arm 12 , 41 Bucket 16, 44 Offset cylinder 8, 63 Second boom component (main boom member)
9, 64 Second boom component (link rod member)

Claims (2)

A driver's cab mounted on the upper swing body, a first boom connected to the upper swing body on the side of the driver's cab in a vertically swingable manner, and a left and right swing at the tip of the first boom. A second boom that is movably connected, a third boom that is swingably swingable in the left-right direction at the tip of the second boom, and a swinger that is swingable in the vertical direction at the tip of the third boom. Side gutter excavation having an arm and a work tool connected to the tip of the arm so as to be swingable in the vertical direction, and allowing the center line of the arm to swing in the horizontal direction parallel to the first boom. Hydraulic excavator
The first boom is formed on a plane substantially parallel to a surface of the cab facing the cab side surface side,
The second boom is connected to the first boom and the third boom so as to be swingable in the left-right direction, and has a main boom member and a link rod member arranged in parallel, and the second boom is The cab side surface of the main boom member is positioned on substantially the same plane as the cab side surface of the first boom in a state where the first boom is not swung, and the link rod member is the first boom. By projecting from the side opposite to the operator's cab side of the boom, the side of the operator's cab side of the first boom and the operation of the second boom can be performed without swinging the second boom with respect to the first boom. The room side surface is positioned on substantially the same plane,
An offset cylinder for swinging the second boom is disposed on the side surface of the main boom member opposite to the cab,
In a state where the second boom is not swung with respect to the first boom, the front-rear direction center line of the third boom is offset to the opposite side of the operator's cab from the front-rear direction center line of the first boom, By connecting the arm to the third boom so that the front-rear direction center line of the arm is positioned on the front-rear direction center line of the boom,
The center line in the front-rear direction of the arm is offset to the opposite side of the cab from the center line in the front-rear direction of the first boom in a state where the second boom is not swung with respect to the first boom. Boom offset hydraulic excavator.   The main boom member and the link rod member are second boom constituent members having substantially the same shape and arranged substantially symmetrically, and the offset cylinder is arranged between the left and right second boom constituent members. The boom offset type hydraulic excavator according to claim 1.

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