JP2765451B2 - Excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavator for excavating a trench for constructing an underground continuous wall, and more particularly, to an excavator provided with a swivel mechanism capable of swiveling an excavating bucket attached to a tip thereof around a vertical axis. Kelly type excavator.

[0002]

2. Description of the Related Art A conventional Kelly excavator is provided with a bucket capable of grasping rocks, earth and sand, and carrying the same to the ground surface, and a Kerry rub for opening and closing the bucket.
It is provided below the kelly bar suspended by a crane or the like.

[0003] Such a Kelly excavator is mainly used for an underground diaphragm wall construction method. In the excavation process, excavation of the ground by a Kelly excavator is performed while preventing collapse of a hole wall with a stable liquid such as bentonite or polymer. To form a trench in the ground.

[0004] After the formation of the trench, a continuous wall is constructed in the hole wall with cast-in-place concrete or precast concrete. The constructed continuous wall is often used not only as a construction wall, a waterproof wall, etc., but also as a main body as an underground outer wall of a ground structure or an earthquake-resistant wall.

Here, when excavating, it is necessary to make the opening / closing direction of the bucket coincide with the length direction of the trench. Therefore, at the corner of the continuous wall, it is necessary to turn the bucket around the vertical axis by, for example, 90 degrees.

Japanese Utility Model Laid-Open No. 4-82051 discloses a Kelly excavator in which a turning mechanism is provided between a Kelly bar and a Kelly club, which is shown in FIG.

As can be seen from the figure, the Kelly excavator includes a bucket 1 and a Kelly rub 2 for driving the bucket 1 to open and close. The Kelly rub 2 is provided below a Kelly bar 3 suspended by a crane or the like. is there. A turning mechanism 4 is provided between the kelly bar 3 and the kerry club 2.

The turning mechanism 4 of the disclosed Kelly excavator is provided with a worm mechanism including a worm wheel and a worm meshing with the worm wheel, and the worm mechanism allows the bucket to be easily turned even at the corner of the continuous wall. be able to.

[0009]

Here, when the ground is hard and the ground cannot be excavated only by the tightening force of the Kelly club 2, the kelly bar 3 is raised and lowered to strike the bucket 1 against the ground, thereby repeatedly applying an impact force to the ground. In some cases, a so-called chopping operation is performed in which crushing is performed.

[0010] However, the impact force applied to the ground by the chopping operation is caused by the reaction of the bucket 1,
It is also transmitted to the worm mechanism of the turning mechanism 4 via the Kelly Club 2.

Therefore, there has been a problem that the meshing portion of the worm mechanism is damaged by the chopping operation.

The present invention has been made in view of the above circumstances, and has as its object to provide an excavator capable of preventing damage to a worm and a worm wheel due to a chopping operation.

[0013]

In order to achieve the above object, an excavator according to the present invention has a bucket means capable of carrying out earth and sand and the like, and an opening and closing mechanism for opening and closing the bucket means. And a supporting means for supporting the bucket means and the opening / closing mechanism, and a turning mechanism capable of turning the bucket means around a longitudinal axis, wherein the turning mechanism is a first connecting member fixed to the opening / closing mechanism side. A predetermined worm is rotatably mounted on one of the second connecting members fixed to the support means side, and a worm wheel meshing with the worm is mounted on the other of the connecting members. In the excavator, there is provided a fastening mechanism capable of mutually fastening the first and second connecting members, and the fastening mechanism does not allow press-fitting and pulling-out in a predetermined direction. A wedge member, a reaction member disposed on one side of the wedge member and receiving a predetermined pressure from the wedge member when the wedge member is press-fitted, and a reaction force member disposed on the other side of the wedge member when the wedge member is press-fitted. A pressure member receiving a predetermined pressure from the wedge member, wherein the reaction member is fixed to one of the connection members, and the pressure member faces the other of the connection members. It is arranged.

An excavator according to the present invention provides a first excavator.
Alternatively, a predetermined groove is provided in the second connecting member, and the pressing member is fitted into the groove when the wedge member is press-fitted.

Further, the excavator according to the present invention is provided with a guide mechanism for separating the pressing member from the connecting member when the wedge member is pulled out.

[0016]

In the excavator of the present invention, when performing a so-called chopping operation of hitting the bucket means to the ground,
Before the chopping operation, the wedge member of the fastening mechanism is press-fitted between the pressing member and the reaction force member in advance.

When the wedge member is press-fitted, a pressure due to the wedge action acts on the pressurizing member and the reaction force member, so that the pressurizing member moves in a direction substantially orthogonal to the press-fitting direction, and comes into contact with the connecting member. When the press-fitting is continued after the contact, a predetermined pressure acts on the connecting member.

On the other hand, the reaction force of the pressure acting on the connecting member is:
The force is transmitted to the reaction force member fixed to the other connecting member.

Therefore, a predetermined pressure is generated between the two connecting members, and the two members are brought into a pressure-fit state.

When the chopping operation is performed in this state, the impact force transmitted to the first connecting member via the bucket means and the opening / closing mechanism flows to the worm provided with a certain play and the meshing portion of the worm wheel. Instead, it flows to the fastening mechanism in a press-fit state and flows to the support means via the second connecting member.

When it is desired to turn the bucket means, the above-described reverse procedure is performed prior to the turning operation. That is, the wedge member of the fastening mechanism is pulled out from between the pressing member and the reaction force member.

When the wedge member is pulled out, the pressure acting on the pressing member and the reaction force member is released, and the pressure generated between the pressing member and the connecting member also disappears.

When the worm is rotated in this state, the worm wheel meshing with the worm rotates smoothly, and the bucket means turns around the vertical axis.

Further, in the excavator of the present invention, a predetermined groove is provided in the first or second connecting member of the first aspect, and the pressing member is fitted into the groove when the wedge member is press-fitted. Therefore, not only a frictional force but also a predetermined fitting force is generated between the connecting member and the pressing member at the time of wedge press-fitting, and the degree of fastening of the first and second connecting members is further strengthened. .

Further, in the excavator of the present invention, since the guide mechanism for separating the pressing member from the connecting member when the wedge member is withdrawn according to the first aspect of the present invention, the pressing member is provided with the groove of the connecting member when the wedge is withdrawn. Easily come off.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an excavator according to the present invention will be described below with reference to the accompanying drawings. It is to be noted that the same reference numerals are given to components and the like that are substantially the same as those in the conventional technology, and description thereof will be omitted.

The excavator according to the present embodiment is a so-called Kelly excavator, and includes a bucket 1 as a bucket means and a kelly rub 2 as an opening / closing mechanism for opening and closing the bucket 1 as in the prior art. Is provided below the kelly bar 3 as a support means suspended by a crane or the like. A turning mechanism 11 is provided between the kelly bar 3 and the kelly club 2.

FIG. 1 shows the turning mechanism 11 in a longitudinal sectional view.

As can be seen from the figure, the turning mechanism 11 rotatably mounts the worm 15 on the first connecting member 12 fixed to the Kelly club 2 side, and also fixes the worm 15 to the lower end of the Kelly bar 3 via the mounting plate 13. A worm wheel 16 that meshes with the worm 15 is attached to the second connecting member 14. The worm 15 is connected to a hydraulic motor 17 for driving the worm.

FIG. 2 is a cross-sectional view of the turning mechanism 11 taken along the line AA of FIG.

Referring to FIG. 1 again, the excavator of the present embodiment includes a fastening mechanism 21 capable of fastening the first connecting member 12 and the second connecting member 14 to each other.

The fastening mechanism 21 is provided with a wedge member 22 capable of being press-fitted and withdrawn in a predetermined direction, and a predetermined wedge member 22 which is disposed on one side of the wedge member 22, that is, on the right side in FIG. 1 when the wedge member 22 is press-fitted. Reaction member 2 receiving pressure
1 and a pressing member 24 disposed on the other side of the wedge member 22, that is, on the left side in FIG. 1, that receives a predetermined pressure from the wedge member 22 when the wedge member 22 is pressed.

The wedge member 22 is movable in a direction perpendicular to the plane of FIG. 1 by using a hydraulic cylinder 20 provided on a side of the reaction force member 23.

The wedge members 2 are provided so that the guide projections 25 and the guide grooves 26 as guide mechanisms are engaged with each other.
2. The pressure member 24 is provided on the pressure member 24 so as to guide the pressure member 24 toward or away from the connecting member 14 in accordance with the operation of the wedge member 22.

The reaction force member 23 is a U-shaped cross-section member fixed to the connecting member 12 as can be seen in the figure, and the hydraulic cylinder 20 is operated to perform the press-fitting and pulling-out operations of the wedge member 22. Sometimes it also has a function of preventing the guide projection 25 of the wedge member 22 from coming off the guide groove 26 of the pressing member 24.

On the other hand, the pressing member 24 is disposed to face the connecting member 14, and when the wedge member 22 is press-fitted, its tip is fitted into a fitting groove 27 provided on the outer periphery of the connecting member 14. ing.

As can be seen from FIG. 1, the fastening mechanism 21
Are substantially symmetrical, but since their structures are substantially the same, only one of them will be described, and the other description will be omitted.

FIG. 3 shows that the fastening mechanism 21 is connected to the hydraulic cylinder 20.
FIG. 4 is a cross-sectional view of the fastening mechanism 21 taken along line BB in FIG. 1.

As can be seen from FIG. 4, a link member 32 is joined to the tip of the piston rod 31 of the hydraulic cylinder 20. When the hydraulic cylinder 20 is operated, the link member 32 moves the link member mounting position 33. It is designed to rotate around the center.

The wedge member 22 is joined to an intermediate portion of the link member 32, and when the hydraulic cylinder 20 is operated, the wedge member 22 is moved to the reaction force member 23 and the pressure member 24.
It is adapted to be press-fitted or pulled out between.

Next, the operation of the excavator of this embodiment will be described.

First, when performing a so-called chopping operation in which the bucket 1 is hit against the ground, the hydraulic cylinder 20 is operated in advance before the chopping operation and the wedge member 2 is moved.
2 is press-fitted between the pressing member 24 and the reaction member 23.

When the wedge member 22 is press-fitted, the outer side surface of the guide projection 25 provided on the wedge member 22 is
The pressing member 24 is moved in a direction in which the pressing member 24 approaches the connecting member 14, and then the pressing member 24 is fitted into the fitting groove 27 provided in the connecting member 14.

When the press-fitting is further performed, the pressure by the wedge action acts on the pressurizing member 24 and the reaction force member 23, and the tip of the pressurizing member 24 is firmly fitted into the fitting groove 27 (FIGS. 1 and 4). State).

On the other hand, the reaction force of the pressure acting on the connecting member 14 is:
The force is transmitted to the other connecting member 12 via the reaction member 23.

Accordingly, a predetermined pressure is generated between the two connecting members 12 and 14, and a pressure-fit state is established.

When a chopping operation is performed in this state, the impact force transmitted to the first connecting member 12 via the bucket 1 and the kerry club 2 causes the worm 15 and the worm wheel 16 provided with a certain play to mesh with each other. Flow to the fastening mechanism 21 in a pressure-fit state,
Flows through the connecting member 14 to the kelly bar 3.

Therefore, even when the chopping operation is performed, no impact force acts on the worm 15 and the worm wheel 16, and damage to the meshing portion between them can be avoided.

Excavation proceeds in this state, and when the excavation position reaches the corner of the underground wall, the bucket 1 is turned around the vertical axis.

When the bucket 1 is turned, the above-described reverse procedure may be performed prior to the turning operation. That is, FIG.
As shown in (1), the hydraulic cylinder 20 is operated to pull out the wedge member 22 from between the pressing member 24 and the reaction member 23.

When the wedge member 22 is pulled out, the inner side surface of the guide projection 25 provided on the wedge member 22
Since the pressure member 24 is moved in a direction away from the connection member 14 by contacting the side surface of the guide groove 26 provided in the pressure member 26, the pressure generated between the pressure member 24 and the connection member 14 disappears.

In this state, the pressure fitting state of the connecting member 12 and the connecting member 14 has been released. Therefore, when the hydraulic motor 17 is operated to rotate the worm 15,
Due to the interaction with the worm wheel 16 that meshes with the worm wheel, the worm 15 smoothly rotates around the worm wheel 16, and thus the bucket 1 turns around the vertical axis.

As described above, the excavator of this embodiment is
The wedge member is press-fitted so that the Kelly Club side connection member and the Kelly Bar side connection member are in a press-fit state, and the wedge member is pulled out to release the press-fit state. The force can be transmitted to the upper kelly bar via a fastening mechanism provided with a wedge member, instead of the engaging portion between the worm and the worm wheel.

Therefore, it is possible to avoid damage to the meshing portion between the worm and the worm wheel due to the chopping operation.

Further, in the excavator of this embodiment, a predetermined fitting groove is provided in the second connecting member, and the pressing member is fitted into the fitting groove when the wedge member is press-fitted. Not only a frictional force but also a predetermined fitting force is generated between the connecting member and the pressing member at the time of press-fitting, and the degree of fastening of the first and second connecting members can be further increased.

In this embodiment, the fastening mechanisms are provided symmetrically. However, the present invention is not limited to this, and three or more fastening mechanisms may be arranged in a well-balanced manner. When the fastening mechanisms are used alone rather than in pairs as in the present embodiment, care must be taken, for example, to provide a support mechanism on the opposite side so that the force direction is not biased.

Further, in this embodiment, a predetermined fitting groove is provided in the second connecting member so that the pressing member is fitted into the fitting groove when the wedge member is press-fitted. When the force is small or when the frictional force due to the contact between the second connecting member and the pressing member is large, the fitting groove may be omitted and the pressure fitting may be performed only by the frictional force.

Further, in this embodiment, the reaction member of the fastening mechanism is fixed to the connecting member on the Kelly rub side, and the pressing member is brought into contact with the connecting member on the Kelly bar side. The reaction force member of the mechanism may be fixed to the connection member on the kelly bar side, and the pressing member may be configured to contact the connection member on the kelly bar side.

In this embodiment, the guide mechanism including the guide projection and the guide groove is provided. However, when the wedge member is pulled out, the wedge member can be separated from the connecting member without substantially applying a force to the pressing member. For example, when the fitting groove is not provided, the guide protrusion and the guide groove may be omitted, and the wedge member and the pressing member may be simply configured to abut.

[0060]

As described above, the excavator of the present invention
A bucket means capable of carrying out soil and the like, an opening / closing mechanism for opening and closing the bucket means, a supporting means for supporting the bucket means and the opening / closing mechanism, and a turning mechanism capable of turning the bucket means around a longitudinal axis. The turning mechanism is configured to rotatably attach a predetermined worm to one of a first connecting member fixed to the opening / closing mechanism side and a second connecting member fixed to the support means side, In an excavator configured by attaching a worm wheel that meshes with a worm to the other of the connecting members, the excavator includes a fastening mechanism that can fasten the first and second connecting members to each other, and the fastening mechanism includes a predetermined mechanism. A wedge member capable of being press-fitted and withdrawn in a direction, and a predetermined wedge member which is disposed on one side of the wedge member and which is pressed when the wedge member is pressed. A reaction member receiving a force, and a pressure member disposed on the other side of the wedge member and receiving a predetermined pressure from the wedge member when the wedge member is press-fitted. Since the pressing member is fixed to one of the connecting members and is arranged to face the other of the connecting members, damage to the worm and the worm wheel due to the chopping operation can be avoided.

[0061]

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an excavator according to an embodiment.

FIG. 2 is a cross-sectional view taken along line AA of FIG.

FIG. 3 is a side view of the excavator according to the embodiment.

FIG. 4 is a transverse sectional view taken along the line BB of FIG. 1;

FIG. 5 is a diagram for explaining the operation of the embodiment.

FIG. 6 is an overall side view of a conventional excavator.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 bucket (bucket means) 2 kelly rub (opening / closing mechanism) 3 kelly bar (supporting means) 11 turning mechanism 12 first connecting member 14 second connecting member 15 worm 16 worm wheel 21 fastening mechanism 22 wedge member 23 reaction force member 24 Pressing member 25 Guide protrusion (guide mechanism) 26 Guide groove (guide mechanism) 27 Fitting groove

Claims (3)

(57) [Claims] 1. A bucket means capable of carrying out earth and sand, an opening and closing mechanism for opening and closing the bucket means, a supporting means for supporting the bucket means and the opening and closing mechanism, and the bucket means being pivotable about a longitudinal axis. A turning mechanism, wherein the turning mechanism is fixed to a first opening / closing mechanism side.
A predetermined worm is rotatably attached to one of the connecting member and the second connecting member fixed to the supporting means, and a worm wheel meshing with the worm is attached to the other of the connecting members. An excavator configured as described above, further comprising a fastening mechanism capable of mutually fastening the first and second connecting members, wherein the fastening mechanism includes a wedge member capable of press-fitting and pulling out in a predetermined direction, and a wedge member. A reaction force member arranged on one side and receiving a predetermined pressure from the wedge member when the wedge member is press-fitted, and a predetermined pressure from the wedge member when the wedge member is press-fitted and arranged on the other side of the wedge member. A receiving member, wherein the reaction member is fixed to one of the connecting members, and the pressing member is opposed to the other of the connecting members. An excavator, characterized in that the excavator is arranged facing the excavator. 2. The excavator according to claim 1, wherein a predetermined groove is provided in the first or second connecting member, and the pressing member is fitted into the groove when the wedge member is press-fitted. 3. The excavator according to claim 1, further comprising a guide mechanism for separating the pressing member from the connecting member when the wedge member is pulled out.