JP3366602B2 - Front attachment support device for ground excavator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front attachment support device for a ground excavator,
Also applicable to pile driving machines such as earth drilling machines. 2. Description of the Related Art An outline of a conventional front attachment support device in a ground excavator of this type will be described with reference to FIGS. 2 to 4. FIG. In FIG. 2, 1 indicates a ground excavator. The ground excavator 1 is a lower traveling body 2
The upper swing body 3 is mounted on the upper swing body 3 and the boom 4
Are pivotally supported by an up-and-down cylinder 5 so as to be able to undulate.
The boom hoist cylinder 5 has its lower end pivotally supported by the upper swing body 3 and its upper end pivotally attached to a lower portion of the boom 4.
The boom 4 is formed so that it can be raised and lowered in the front-rear direction by the expansion and contraction operation of the boom raising and lowering cylinder 5. A rope 6 fed from a winch provided on the upper swing body 3 is hung down through a sheave 7 provided at the top of the boom 4, and a kerry bar 8 is connected to the rope 6; The kelly bar 8 is suspended so as to be vertically movable by winding and unwinding the rope 6. Although not shown in detail, the kerry bar 8 is supported by a rotary table that constitutes a part of the excavation frame 9, and the rotary table is connected to a motor, and is connected to the rotary table. Rotate the Keriba 8
To form the kerry bar 8 rotatably,
The kelly bar 8 is vertically movably supported in the rotary table by means such as spline fitting. The excavation frame 9 is supported by a front attachment frame 10 whose base is pivotally supported on the upper swing body 3,
A shaft excavation bucket 11 and the like are connected to the lower end of the kelly bar 8, and the ground is excavated by the shaft excavation bucket 11 excavating. On the other hand, the excavating frame 9
And is supported by an excavating frame support rope 12 which is extended from the top of the boom 4 and is further supported by a front attachment frame 10 which is extended from another winch. Supported. The excavating frame 9 of the prior art is supported by an excavating frame supporting rope 12, and the front attachment frame 10 is supported by a front attachment undulating rope 13, so that when the rope is broken, There is a risk that the frame 9 and the front attachment frame 10 may fall. Furthermore, the installation and adjustment of these ropes involves danger because they are performed at a high place. Furthermore, at the time of excavation work, the excavation frame 9 and the front attachment frame 10,
Alternatively, there is a defect that the front attachment such as the above-described rope swings in the front-rear direction, and the center of the excavation hole is misaligned. Next, a conventional example shown in FIG. 3 will be described. The difference between the ground excavator 1A shown in the figure and the ground excavator 1 shown in FIG.
The front attachment frame 10 is attached to the mast 1 by interposing a front attachment undulating cylinder 15A between the mast 14 and the upper end of a mast 14 provided on the upper rotating body 3.
4 is that a configuration of supporting at the upper end is employed.
The remaining configuration is the same as the configuration of the ground excavator 1 shown in FIG. 2 described above. In the conventional example shown in FIG. 3, the front attachment frame 10 is supported by the upper end of the mast 14, so that the boom 4 and the front attachment do not move together, so that the boom 4 is lowered or the front attachment frame is not moved. At the time of raising 10, there is a defect that the boom 4 and the front attachment interfere and break. FIG. 4 shows still another conventional ground excavator 1B.
Is shown. The difference between the ground excavator 1B and the ground excavators 1 and 1A shown in FIGS. 2 and 3 is that the front attachment frame 10A is mounted on the boom 4, and the excavation frame support link is parallel to the front attachment frame 10A. 16 is interposed between the boom 4 and the excavating frame 9, and a front attachment undulating cylinder 17 is interposed between the middle part of the front attachment frame 10 </ b> A and the boom 4, and the expansion and contraction operation of the front attachment undulating cylinder 17 is performed. Thus, the vertical position of the excavation frame 9 can be arbitrarily changed via the front attachment frame 10A. Other configurations are the same as those of the ground excavators 1 and 1A shown in FIGS. 2 and 3, and therefore, the target portions are denoted by the same reference numerals and description thereof is omitted. Since the ground excavator 1B shown in FIG. 4 has the front attachment frame 10A mounted on the boom 4, the excavation thrust reaction forces the boom 4 and the entire front attachment to oscillate during excavation work. Misalignment or bending of the hole occurs. In order to prevent the danger caused by the breakage of the rope, to suppress the swing of the boom and the front attachment due to the reaction force of the excavation thrust, and to minimize the misalignment of the excavation hole, a technical solution to be solved. Problems arise, and an object of the present invention is to solve the problems. SUMMARY OF THE INVENTION The present invention has been proposed to achieve the above object. An upper revolving unit is mounted on a lower traveling unit, and a boom is raised and lowered on the upper revolving unit. A rope is pivotally supported by a cylinder so as to be able to move up and down, and a rope fed from a winch is hung from the top of the boom to suspend a kelly bar, and the kelly bar is supported by a drilling frame so as to be vertically movable and rotatable. Along with the excavation frame, the excavation frame is supported by a front attachment frame formed so as to be able to undulate, and further, in a ground excavator that performs an excavation operation by connecting a shaft excavation bucket or an earth auger to the lower end of the kelly bar, One end of the front attachment frame is pivotally supported by the upper revolving unit, and the tip of the front attachment frame is pivotally attached to the excavation frame. The one end of the lifting cylinder is located below the boom-side pivot of the boom lifting cylinder, close to the boom pivot point and pivotally supported by the boom, and the other end is pivotally connected to the front attachment frame. In addition, the present invention provides a front attachment support device for a ground excavator in which an excavation frame up / down cylinder is interposed between the front attachment frame and the excavation frame. An embodiment of the present invention will be described below in detail with reference to FIG. The parts common to the conventional example are denoted by the same reference numerals, and the description thereof will be omitted. In the figure, the excavation frame 9 supporting the kelly bar 8 is supported by the front attachment frame 10 with the lower end pivotally attached to the upper end of a front attachment frame 10 pivotally supported by the upper swing body 3. The front attachment frame 10 is supported by a front attachment undulating cylinder 17A so that the front attachment frame 10 can be raised and lowered with a pivot portion for the upper swing body 3 as a rotation fulcrum. The front attachment up-and-down cylinder 17A is pivotally supported at one end near the pivot point P of the boom 4 and at a lower portion of the pivotal support portion PA of the boom up-and-down cylinder 5 with respect to the boom 4. By pivotally connecting the other end to the upper end of the front attachment frame 10, the front attachment frame 10
Is formed so that can be supported at an arbitrary angle. Thus, the front attachment undulating cylinder 17
Since the pivot portion PB of A is provided below the boom hoist cylinder 5, the pivot portion PA of the boom hoist cylinder 5 for the boom 4 and the pivot portion PB of the front attachment hoist cylinder 17A for the boom 4 are obtained.
Are provided close to each other. That is, in general, the pivot PA of the boom hoist cylinder 5 with respect to the boom 4 is provided at a lower portion of the boom 4 and
The reason why the pivot portion PB of the front attachment undulation cylinder 17A is provided below the pivot portion PA of the boom undulation cylinder 5 is to make the pivot portion PB as close as possible to the pivot point P of the boom 4. By doing so,
The acting force on the boom hoist cylinder 5 due to the excavation thrust reaction force during the excavation work can be made as small as possible. An excavating frame up / down cylinder 18 is interposed between the upper end of the excavating frame 9 and an intermediate portion of the front attachment frame 10. Adjusted and supported. Therefore, in conjunction with the expansion and contraction operation of the front attachment up-and-down cylinder 17A, the kelever 8 can be used at an arbitrary angle not only in the vertical direction but also in the front-rear direction. Furthermore,
Since the front attachment up / down cylinder 17A, the excavation frame up / down cylinder 18 and the boom up / down cylinder 5 can be fixed at any lengths, the excavation radius can be positioned at any position, and workability is improved. improves. In addition, since the excavation frame 9 and the front attachment frame 10 are supported by the hydraulic cylinder, the ground excavator 1C of the present invention can be set up from the transportation position to the posture during excavation work using a conventional rope supporting method. In comparison with, it has become possible to implement it extremely safely and quickly. The present invention can be applied not only to the crawler type but also to the wheel type of the undercarriage 2, and the present invention can be variously modified without departing from the spirit of the present invention.
And it goes without saying that the present invention extends to the modified one. According to the present invention, as described in detail in the first embodiment, the base end of the front attachment frame is pivotally supported by the upper revolving unit, so that the excavating thrust reaction force is received by the entire body. Therefore, it is possible to suppress the swinging of the boom and the front attachment in the left-right direction, and it is possible to minimize the bending of the drilling hole. Further, by switching the support of the excavation frame and the front attachment frame from the conventional rope system to the hydraulic cylinder system, the danger of the excavation frame falling due to the breakage of the rope can be prevented, and the front and rear of the front attachment can be prevented. By reducing the swing in the direction, it is possible to reduce the misalignment of the borehole. In addition, all the various defects of the rope support system can be eliminated. Further, by providing a pivot for the boom of the front attachment up / down cylinder close to the pivot point of the boom, the pivot for the boom of the boom up / down cylinder and the pivot of the front attachment up / down cylinder come closer. Therefore, during the excavation work, the acting force on the boom raising / lowering cylinder due to the excavation thrust reaction force becomes small, and thus the rocking in the front-rear direction is prevented from being transmitted to the boom and the front attachment as much as possible. Can be improved. Further, since the one end of the front attachment raising / lowering cylinder is pivotally supported by the boom, the boom and the front attachment move together, so that when the boom is lowered or the front attachment is raised, the boom is moved. This is an invention which has a truly remarkable effect, for example, it is possible to prevent mutual interference between the front attachment and the front attachment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a ground excavator, showing one embodiment of the present invention. FIG. 2 is a side view of a conventional ground excavator. FIG. 3 is a side view of another conventional ground excavator. FIG. 4 is a side view of still another conventional ground excavator. [Description of Signs] 1C Ground Excavator 2 Lower Traveling Body 3 Upper Revolving Structure 4 Boom 5 Boom Raising Cylinder 6 Rope 8 Keriva 9 Excavating Frame 10 Front Attachment Frame 17A Front Attachment Raising Cylinder 18 Excavating Frame Cylinder

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-11-270267 (JP, A) JP-A-1-295991 (JP, A) JP-A-4-22584 (JP, U) JP-J 5- 47823 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21B 15/00-15/04 E21B 11/00

Claims (1)

(57) [Claims 1] An upper revolving structure is mounted on a lower traveling structure, and a boom is pivotally supported on the upper revolving structure by a boom hoist cylinder so as to be able to move up and down, and is extended from a winch. A rope is hung from the top of the boom to suspend a kelly bar, the kelly bar is supported by the excavation frame so as to be vertically movable and rotatable, and the excavation frame is a front attachment frame formed to be undulating. Supported by
Further, in a ground excavator that performs an excavation operation by connecting a shaft excavating bucket or an earth auger to a lower end of the kelly bar, the front attachment frame has one end pivotally supported by an upper revolving body, and a tip end thereof. Is pivotally attached to the excavation frame, and one end of the front attachment up-and-down cylinder is located below the boom-side pivot of the boom up-and-down cylinder and approaches the boom pivot point to pivotally support the boom. A front attachment frame in a ground excavator, wherein the other end is pivotally attached to a front attachment frame, and an excavation frame undulating cylinder is interposed between the front attachment frame and the excavation frame. .