JP4425169B2 - Swivel work machine - Google Patents

Description

  The present invention relates to a turning work machine such as a backhoe.

  Conventionally, as a swivel work machine, a crawler type traveling body in which a crawler belt is wound around front and rear wheels is provided on both the left and right sides of a track frame, and a swivel bearing is provided on the track frame of the traveling apparatus. A swivel board that is supported so as to be rotatable about a vertical pivot axis, and a swing bracket to which a boom of an excavator is attached can be pivoted about a vertical swing axis at the front of the swivel board. A supporting bracket for supporting is provided so as to protrude forward from the swivel board, and the swivel axis is positioned at a central portion between the left and right crawler type traveling bodies and at a substantially central portion between the front and rear end portions of the crawler type traveling body. There is a backhoe (see Patent Document 1).

The excavator includes a boom pivotally connected to an upper portion of a swing bracket supported pivotally around a vertical axis at a front portion of a swing frame, and an arm pivotally connected to a tip end side of the boom. And a bucket pivotally connected to the tip side of the arm.
JP 2001-90110 A

In the conventional backhoe, if the distance between the swing axis and the outer peripheral edge of the swing bearing is large, during excavation work, a support bracket, a swing substrate, etc. are placed between the swing axis and the outer peripheral edge of the swing bearing. There is a problem that the operator bends elastically and makes the operator feel a slight but fluffy swing.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a turning work machine that solves the above-mentioned problem by increasing the distance between the swing axis and the outer peripheral edge of the turning bearing.

The technical means taken by the present invention in order to solve the technical problem includes a traveling device in which crawler-type traveling bodies formed by winding a crawler belt around front and rear wheels are provided on both right and left sides of a track frame. A swing board is provided on a track frame of the traveling apparatus, and is supported by a swing bearing so as to be rotatable around a pivot axis in the vertical direction. A swing bracket to which a boom of the excavator is attached is provided at the front of the swing board. A support bracket that is pivotably supported around a swing axis in the vertical direction is provided so as to protrude forward from the swivel board, and the support bracket is provided on the swivel board so as to extend rearward from the front end side of the swivel board. secured to the upper and lower surfaces of the front end of the anchored pair of longitudinal ribs, wherein the swivel axis, and prior to the crawler type traveling body in the central portion between the left and right crawler type traveling body In rotary working machine is positioned at a substantially central portion between the ends,
The outer peripheral edge of the slewing bearing is brought close to the front end of the slewing substrate so that the slewing bearing and the support bracket overlap in plan view ,
The midway portion in the front-rear direction of one vertical rib is disposed in the front-rear direction so as to pass through the pivot axis, and the portion of the upper support bracket that is overlapped with the one vertical rib is the one vertical rib. It is characterized in that it extends backward on the rib to the vicinity of the pivot axis .

Further, the boom is pivotally connected to the upper part of the swing bracket so as to be swingable up and down, and one end side of a boom cylinder that swings the boom up and down is pivotally connected to the front part of the swing bracket and the other end side of the boom cylinder is connected to the swing bracket. It is pivotally connected to the boom, and the pivot part on the one end side of the boom cylinder overlaps with the vertical line passing through the front end of the grounding part of the crawler type traveling body, or the crawler type traveling body. It is good to be located behind the front end of the grounding part.
The relationship between the distance A between the swing axis and the outer peripheral edge of the swing bearing and the distance B between the swing axis and the outer peripheral edge of the swing bearing is preferably A: B≈13: 21.

In addition, the cabin is mounted on the swivel board so as to be located on one side of the swivel board, and the support bracket is located on the side of the cabin from the center of the swivel board in the left-right direction opposite to the cabin arrangement side. The one vertical rib is positioned so that the front side of the one vertical rib is located on the side of the cabin side surface and the rear side is bent outward in the left-right direction so as to be positioned below the cabin. The front side of the rib may be formed higher than the rear side .

  According to the present invention, the swing axis approaches the outer peripheral edge of the swing bearing, and the bending of the support bracket, the swing board, and the like between the swing axis and the outer peripheral edge of the swing bearing during excavation work is reduced. be able to.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4, reference numeral 1 denotes a backhoe exemplified as a turning work machine, and the backhoe 1 includes a lower traveling device 2 and an upper turning body 3.
As shown in FIGS. 1 and 8, the traveling device 2 includes a track frame 4 and left and right crawler traveling bodies 5.
The track frame 4 is mainly composed of a center frame 6 at the center in the left-right direction and side frames 7 provided on both the left and right sides of the center frame 6.

The crawler type traveling body 5 is disposed between the front and rear wheels 8 and 9 supported on the front and rear of the side frame 7 so as to be rotatable around the left and right axes, and is disposed between the front and rear wheels 8 and 9. The crawler belt 11 has a plurality of rollers 10 rotatably supported around and a crawler belt 11 formed in an endless belt shape from a rubber-like elastic member. The crawler belt 11 is hung over the front and rear wheels 8 and 9 and the rollers 10. Dressed up.
In this crawler type traveling body 5, the front wheel 8 is a driven wheel (idler) and the rear wheel 9 is a drive wheel (sprocket), which is provided on the rear end side of the side frame 7. The drive wheel 9 is rotationally driven by the pressure motor 12 so that the crawler belt 11 circulates and rotates in the circumferential direction so that the backhoe 1 travels.

The upper swing body 3 includes a swivel base 14 that is supported by the traveling device 2 via a swivel bearing 13 so as to be rotatable about a vertical pivot axis X, and a support bracket provided at a front portion of the swivel base 14. 15, excavator 17, cabin 18 mounted on swivel base 14, equipment such as engine 19 and radiator 20 supported on swivel base 14, tank such as fuel tank 21 and hydraulic oil tank 22. It has kind etc.
The swivel base 14 includes a swivel frame 23 serving as a skeleton, and a protector 24 that is attached to the rear part of the swivel frame 23 to form a rear part of the swivel base 14 and has a balance weight function for balancing the weight with the excavator 17. And is composed mainly of.

  As shown in FIGS. 5 to 7, the swivel frame 23 has a swivel board 25 made of a thick plate that constitutes the bottom of the swivel base 14, and a pair of left and right as reinforcing bodies of the main body is provided on the swivel board 25. The vertical ribs 27L and 27R are arranged from the front part to the rear part and fixed by welding or the like. On the front end side of the left and right vertical ribs 27L and 27R, a pair of support brackets 15 made of a plate material are provided. The reinforcing member, various devices, brackets for attaching tanks, stays and the like are fixed on the turning substrate 25 by welding, and the turning frame 23 is constituted by these.

The protector 24 is divided into three parts from a center protector 24A at the center in the left-right direction and side protectors 24B, 24C on both the left and right sides (even if the center protector 24A and the side protectors 24B, 24C are integrally formed. Good).
A cabin 18 forming a driver's cab is mounted near the left front part of the swivel frame 23, and a driver's seat 28 is disposed on the left side of the swivel base 14 in the front-rear direction center side. The upper surface of the front part is covered by steps constituting the bottom of the cabin 18.
The front side of the side protector 24 </ b> B on the left side surface of the swivel base 14 and the left side from the front support bracket 15 are covered with a swivel cover 30.

The rear upper surface and the right upper surface of the swivel base 14 are open. The engine 19 is disposed horizontally on the rear portion of the swivel frame 23, the radiator 20 is disposed on the right side of the engine 19, and the left side of the engine 19 is disposed on the left side. A hydraulic pump 31 is disposed, and these are covered by an openable open / close bonnet 32 and an engine bonnet 34 constituted by a fixed bonnet 33 fixed to the revolving frame 23 side.
A hydraulic oil tank 22 for storing hydraulic oil for hydraulic equipment is disposed on the right side of the turning frame 23 on the front side of the radiator 20, and a fuel tank 21 is disposed on the front side of the hydraulic oil tank 22. A battery 35 is disposed on the outer side in the left-right direction of the front portion of the front portion 22, and a control valve for controlling each hydraulic device provided in the backhoe 1 is disposed on the upper side of the battery 35. Covered by.

Further, the upper side of the turning frame 23 between the cabin 18 and the side bonnet 37 is covered with a cover member 36.
The left and right vertical ribs 27L and 27R are arranged vertically so that the thickness direction is perpendicular to the vertical direction, and extend rearward from the front end side of the swivel board 25 on the swivel board 25. The front portion is inserted between the upper and lower support brackets 15.
The upper support bracket 15 is formed in a flat plate shape, and the rear part is welded and fixed to the upper surfaces of the vertical ribs 27L and 27R. The lower support bracket 15 is fixedly welded to the upper surface of the revolving board 25 and the vertical ribs 27L and 27R. The front portion is spaced upward from the swivel board 25, and the upper and lower support brackets 15 protrude forward from the front surface of the swivel base 14 (the front end of the swivel board 25).

The left side of the upper support bracket 15 extends rearward on the left vertical rib 27L to the vicinity of the pivot axis X.
The upper and lower support brackets 15 are located on the right side of the cabin 18, and the bottom of the cabin 18 is located below the upper support bracket 15.
A support cylinder 38 having a vertical axis is provided at the front portion of the upper and lower support brackets 15 so as to extend over the upper and lower support brackets 15, and the front ends of the left and right vertical ribs 27 </ b> L and 27 </ b> R are provided on the support cylinder 38. The swing bracket 40 is swingably mounted around the swing axis Y in the vertical direction by a support shaft 39 inserted through the support cylinder 38 and the vertical support bracket 15. The bracket 40 is swung by expansion and contraction of a swing cylinder that is a hydraulic cylinder disposed on the right side of the swivel base 14.

The excavator 17 includes a boom 42 whose base side is pivotally connected to the upper part of the swing bracket 40 via a pivot 41 so as to be pivotable about a left and right axis, and is vertically swingable. An arm 43 that is pivotally connected to be pivotable about an axis and is swingable back and forth, and is pivotally connected to a distal end side of the arm 43 so as to be rotatable about a left and right axis to be freely squeezed and dumped. Bucket 44.
The excavator 17 includes a boom cylinder 46 that swings the boom 42, an arm cylinder 47 that swings the arm 43, and a bucket cylinder 48 that swings the bucket 44. These cylinders are hydraulic cylinders. Has been.

One end side of the boom cylinder 46 is pivotally connected to the front half of the swing bracket 40 in the vertical direction via a pivot shaft 49 so as to be rotatable about the left and right axis. The other end side of the boom cylinder 46 is the lower surface of the boom 42. It is pivotally connected to the middle part in the longitudinal direction on the side so as to be rotatable about the left and right axis.
The front end sides of the left and right vertical ribs 27L, 27R are formed high in the vertical direction, the rear side of the left and right vertical ribs 27L, 27R are formed low in the vertical direction, and the cabin 18 side (left side) of the left and right vertical ribs 27L, 27R. ) Of the vertical rib 27L is disposed inwardly in the left-right direction of the cabin 18 and substantially parallel to the right side surface of the cabin 18, and the rear side of the vertical rib 27L on the cabin 18 side is outward in the left-right direction. It is bent toward the bottom and arranged below the cabin 18.

The left vertical rib 27L may be formed in a straight line in the front-rear direction.
A reinforcing plate 51 that is disposed vertically and in the front-rear direction and is welded onto the swivel board 25 is provided on the outer side in the left-right direction of the rear end side of the left vertical rib 27L. The rear side ends of the left vertical ribs 27L and 27R are connected to the plate 51.
Further, the rear end portion of the reinforcing plate 51 is connected to the left side of the front surface of the block-shaped reinforcing member 52 provided on the center side in the left-right direction on the rear end side on the revolving substrate 25, The rear portion of the right vertical rib 27R is connected by a reinforcing plate 53, and the reinforcing plate 53 and the left reinforcing plate 51 are connected by a connecting plate 54.

The block-shaped reinforcing member 52 also serves as a weight.
A through hole 56 for inserting an upper part of a swivel joint for supplying / returning pressure oil to / from hydraulic equipment on the traveling device 2 side from the control valve is provided on the turning center side of the turning substrate 25, and the left vertical The rib 27L is provided so as to cross the through hole 56 in the front-rear direction, and the left vertical rib 27L is formed with a through hole 57 for passing a hydraulic hose at a position corresponding to the through hole 56. Yes.
The swivel board 25 is supported by the center frame 6 of the track frame 4 of the traveling device 2 via a swivel bearing 13 so as to be rotatable around a swivel axis X in the vertical direction. The swivel bearing 13 includes an outer race 58, The inner race 59 has a ball 60 disposed between the outer race 58 and the inner race 59. The outer race 58 is fixed to the mounting portion 61 on the bottom surface side of the turning substrate 25 with a bolt. Is fixed to the mounting portion 62 on the upper surface side of the center frame 6 with bolts.

The center of the slewing bearing 13, that is, the slewing axis X is located at the center between the left and right crawler type traveling bodies 5 and substantially at the center between the front and rear ends of the crawler type traveling body 5 (in the example shown in the figure). The distance D from the turning axis X to the front end of the crawler type traveling body 5 is slightly shorter than the distance C from the turning axis X to the rear end of the crawler type traveling body 5).
The slewing bearing 13 is formed in a size close to the front end 25a of the slewing substrate 25 so that the slewing bearing 13 and the support bracket 15 overlap in plan view. As a result, the swing axis Y approaches the outer peripheral edge of the swivel bearing 13, and the support bracket 15 and the swivel board 25 are bent between the swing axis Y and the outer peripheral edge of the swivel bearing 13 during excavation work. And the burden due to the load acting on the swivel bearing 13 during excavation work can be reduced.

In the present embodiment, a distance A (in this embodiment, 305.891 mm) between the swing axis Y and the outer peripheral edge of the swing bearing 13 and a distance between the swing axis X and the outer peripheral edge of the swing bearing 13. The relationship with B (in this embodiment, 494.5 mm) is A: B≈13: 21.
In the present embodiment, extending portions 63 and 64 extending forward from the front end of the swivel board 25 are provided on the center side in the left-right direction and the right end side of the front end of the swivel board 25. However, the extending portions 63 and 64 may be omitted.

As shown by the phantom lines in FIG. 2, the backhoe 1 having the above-described configuration is configured so that the protector 24 moves outward from the crawler type traveling body 5 in the left-right direction when the turn frame 23 is turned so that the protector 24 faces the left-right direction. Although it is a standard backhoe 1 that protrudes, the rear end of the protector 24 is formed so as to be positioned in front of the rear end of the crawler type traveling body 5. Etc., so as to be as close as possible.
Further, the pivoting portion 65 (the portion pivoted by the pivot 49) on one end side of the boom cylinder 46 is on the side of the vertical line segment Z passing through the front end of the grounding portion of the crawler type traveling body 5 (rotation center of the idler 8). It overlaps when viewed from the side (or may be located on the rear side from the front end of the ground contact portion of the crawler type traveling body 5).

  As in the past, when the pivotal support on one end of the boom cylinder is positioned in front of the front end of the grounding portion of the crawler type traveling body, the load propagating from the boom cylinder side to the swing bracket during excavation is When the rear end of the protector is positioned on the front side of the rear end of the crawler type traveling body, the stability during excavation is lowered. However, as in this embodiment, the boom cylinder 46 is overlapped with a vertical line segment Z passing through the front end of the grounding portion of the crawler type traveling body 5 as viewed from the side, or on the rear side from the front end of the grounding portion of the crawler type traveling body 5. By positioning, the load acting on the swing bracket 40 side from the boom cylinder 46 during excavation is surely received by the ground contact portion of the crawler type traveling body 5. Even if the rear end of 24 is positioned in front of the rear end of the crawler type traveling body 5, stability during excavation is improved (in other words, the boom cylinder 46 The vertical support 65 on one end side of the crawler type traveling body 5 is overlapped with the vertical line segment Z passing through the front end of the grounding part of the crawler type traveling body 5 as viewed from the side, or on the rear side from the front end of the grounding part of the crawler type traveling body 5 By positioning, the rear end of the protector 24 can be positioned in front of the rear end of the crawler type traveling body 5).

  Further, the pivot portion 65 on one end side of the boom cylinder 46 overlaps the vertical segment Z passing through the front end of the grounding portion of the crawler type traveling body 5 as viewed from the side, or the grounding front end of the crawler type traveling body 5 By being positioned further rearward, the swing axis Y approaches the swing bearing 13, and the support bracket 15 and the swing board 25 between the swing axis Y and the outer peripheral edge of the swing bearing 13 during excavation work. Moreover, since the distance between the swing axis Y and the pivot axis X is shortened, stability during excavation can be improved.

It is a side view of a backhoe. It is a top view of a backhoe. (A) is a front view of a backhoe, (b) is a back view of a backhoe. It is a top view of an upper revolving structure. It is a top view of a turning frame. It is a side view of a turning frame. It is a front view of a revolving frame. It is a top view of a traveling apparatus.

Explanation of symbols

2 traveling device 4 track frame 5 crawler traveling body 8 wheels (idler)
9 wheels (drive wheels)
11 Crawler Belt 13 Swivel Bearing 15 Support Bracket 17 Excavator 18 Cabin 25 Swivel Board 25a Front End 40 Swing Bracket 42 Boom 46 Boom Cylinder 65 Axis A Distance between Swing Axis and Swivel Bearing Outer Perimeter B Distance between bearing outer periphery X Rotation axis Y Swing axis Z Line segment

Claims (4)

A traveling device (2) is provided in which a crawler type traveling body (5) formed by winding a crawler belt (11) around front and rear wheels (8, 9) is provided on both left and right sides of a track frame (4). On the track frame (4) of (2), there is provided a turning substrate (25) rotatably supported around a turning axis (X) in the vertical direction via a turning bearing (13). The support bracket (15) for pivotally supporting the swing bracket (40) to which the boom (42) of the excavator (17) is attached to the front portion of the excavator (17) is provided around the swing axis (Y) in the vertical direction. The support bracket (15) is provided so as to protrude forward from (25), and a pair of left and right vertical brackets fixed on the swivel board (25) so as to extend rearward from the front end side of the swivel board (25). Rib (27L, Secured to the upper and lower surfaces of the front end side of the 7R), substantially between the front and rear ends of the swivel axis a (X), the left and right crawler type traveling body (5) and the crawler type traveling body in the center between (5) In the turning work machine located in the center,
The outer peripheral edge of the slewing bearing (13) is brought close to the front end (25a) of the slewing substrate (25) so that the slewing bearing (13) and the support bracket (15) overlap in plan view ,
A midway portion in the front-rear direction of one vertical rib (27L) is disposed in the front-rear direction so as to pass through the pivot axis (X), and the one vertical rib (27L) of the upper support bracket (15). ), The turning work machine is characterized in that it extends backward on the one longitudinal rib (27L) to the vicinity of the turning axis (X) . A boom (42) is pivotally connected to the upper part of the swing bracket (15) so as to be swingable up and down, and one end of a boom cylinder (46) for swinging the boom (42) up and down is attached to the front part of the swing bracket (15). The boom cylinder (46) is pivotally connected and the other end side of the boom cylinder (46) is pivotally connected to the boom (42), and the pivot portion (65) on the one end side of the boom cylinder (46) is connected to the crawler type traveling body (5). It is overlapped with the vertical line segment (Z) passing through the front end of the ground contact portion as viewed from the side, or is located behind the front end of the ground contact portion of the crawler type traveling body (5). The turning work machine according to claim 1. The relationship between the distance A between the swing axis (Y) and the outer peripheral edge of the swing bearing (13) and the distance B between the swing axis (X) and the outer peripheral edge of the swing bearing (13) is expressed as A: B. The turning work machine according to claim 1 or 2, wherein ≒ 13:21. The cabin (18) is mounted on the swivel board (25) so as to be positioned on one side of the swivel board (25), and the support bracket (15) is swung so as to be located on the side of the cabin (18). The board (25) is provided so as to be displaced from the center in the left-right direction on the side opposite to the cabin (18) arrangement side, and the front side of the one vertical rib (27L) is located on the side of the side of the cabin (18). It is formed so that the front side of the one vertical rib (27L) is higher than the rear side so that the rear side is bent outward in the left-right direction and is positioned below the cabin (18). The turning work machine according to any one of claims 1 to 3.

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