JP2002021457A - Pit excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of a pit excavator by accurately clamping a casing tube without damaging the same, and to achieve simplification and downsizing of the structure of the pit excavator. SOLUTION: A lower bearing case 15 is vertically movably supported on a base frame 11 by means of a squeezing/drawing elevating cylinder 21, and a support ring 21 is rotatably supported at the lower bearing case 15 by means of a hydraulic motor 23. On the other hand, an upper bearing cylinder case 25 is vertically movably supported above the lower bearing case 15 by means of a clamp cylinder 26, and an elevating ring 28 is rotatably supported at the upper bearing case 25. Further, a clamp member 31 is connected to the elevating ring 28 via a parallel link mechanism 32, and the clamp member 31 is connected to the support ring 21 via a connection link 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft excavator such as an all-casing excavator used for shaft excavation and foundation pile formation.

[0002]

2. Description of the Related Art An all-casing excavator used as a shaft excavator clamps a casing tube, pushes the casing tube into the ground while turning or swinging the casing tube, cuts the ground with a cutter bit at a lower end portion, and mounts a crane. By operating the grab bucket to excavate and discharge the earth and sand in the casing tube, a shaft is formed.

In such a conventional clamping device for an all-casing excavator, a ring-shaped holder is rotatably supported on a case body that can be raised and lowered with respect to a base frame. Can be clamped. in this case,
While a ring gear is fixed to the case body, a clamp pump is mounted on the holder, and a pinion of the clamp pump is meshed with the ring gear. Therefore, when the holder is rotated by the rotation motor with respect to the case main body, the pinion is rotated by being engaged with the ring gear on the fixed side and being rotated integrally with the holder, and the clamp pump is operated to operate the tightening cylinder. When driven, the casing tube can be clamped by the holder.

[0004]

As described above, in the conventional clamping device, the pinion rotates by rotating with the holder and meshing with the ring gear on the fixed side, and the pump for clamping is operated to generate hydraulic pressure. To drive the tightening cylinder so that the holder clamps the casing tube. Therefore, a switching valve is installed to supply the hydraulic pressure generated by the clamp pump to the tightening cylinder, and complicated operation equipment is required for operating the switching valve on the fixed side, and maintenance and inspection are troublesome. It will be.

In the conventional clamping device, since the holding tool rotates to drive the tightening cylinder to clamp the casing tube, the holding tool slides between the holding tool and the casing tube to generate a flaw. The durability of the holder and the casing tube will be reduced. Furthermore, since the tightening cylinder for operating the holder is provided along the circumferential direction on the outer peripheral portion of the casing tube, the device becomes large, a large installation area is required, and the installation range is limited.

The present invention solves such a problem, and a shaft excavator in which a casing tube is properly clamped without damaging the casing tube to improve reliability and simplify and reduce the size of the structure. The purpose is to provide.

[0007]

According to a first aspect of the present invention, there is provided a shaft excavator having a base frame installed at a predetermined position and a vertically movable cylinder supported by the base frame. Lower casing, and an upper casing disposed above the lower casing,
A clamp cylinder erected between the upper casing and the lower casing; an elevating ring rotatably supported by the upper casing; a driving means for rotating the elevating ring; and a link mechanism parallel to the elevating ring And a clamp member which is connected via the first member and is capable of holding the outer periphery of the casing tube.

Further, in the installation apparatus for a shaft excavator according to the present invention, a support ring is pivotally supported by the lower casing, and the elevating ring is supported by the support ring so as to be able to move up and down. The clamp member is connected to the clamp member via a connection link.

In the installation apparatus for a shaft excavator according to a third aspect of the present invention, the clamp member is divided into a plurality in the circumferential direction, and a projecting portion of the lifting ring extends between the plurality of clamp members. It is characterized by being established.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a partially cutaway front view of an all casing excavator as a shaft excavator according to an embodiment of the present invention.
FIG. 2 is a plan view of the all-casing excavator, FIG. 3 is an external view of the all-casing excavator, FIG. 4 is a schematic cross-section of the clamp mechanism, and FIGS. 5 and 6 schematically show the operation of the clamp mechanism.

As shown in FIGS. 1 to 4, in an all-casing excavator 10 according to the present embodiment, a base frame 11 has a rectangular frame shape, and an outer cylinder 12 opened downward at four corners is fixed. A leveling cylinder 13 is mounted in the cylinder 12, and a grounding plate 14 is attached to a tip end of a drive rod extending below each leveling cylinder 13. Therefore, the levelness of the all-casing excavator 11 can be adjusted by expanding and contracting each leveling cylinder 13.

Above the base frame 11, a lower bearing case 15 as a first casing is disposed, and at four corners of the lower bearing case 15, a main body of a push-pull elevating cylinder 16 is mounted. 17
Are connected to the base frame 11. Therefore, the lower bearing case 1 is moved relative to the base frame 11 by extending and retracting the pushing / pulling elevating cylinder 16.
5 can be raised and lowered.

A ring-shaped guide flange 18 is fixed to the lower bearing case 15.
Support ring 21 via a fitting member 19 and a bearing 20.
Are rotatably supported, and a ring gear 22 having external teeth is fixed to an outer peripheral portion of the support ring 21. The drive gears 24 of the plurality of hydraulic motors 23 as drive means mounted on the lower bearing case 15 mesh with the ring gear 21.

An upper bearing case 25 as a second casing is disposed above the lower bearing case 15, and the upper bearing case 25 and the lower bearing case 15 are provided.
And a clamp cylinder 26 is provided between them. An elevating ring 28 is rotatably supported by the upper bearing case 25 via a bearing 27. In addition,
The lifting ring 28 is partially accommodated in the upper bearing case 25 and has four projections 2 on the inner peripheral surface at equal intervals in the circumferential direction.
Each of the projections 29 is fitted to a guide rod 30 erected on the support ring 21 so as to be vertically movable.

Accordingly, when the drive gear 24 of the hydraulic motor 23 is driven, the support ring 21 can be turned via the ring gear 21, and further, the elevating ring 28 can be turned via the guide rod 30 and the projection 29. it can.
When the clamp cylinder 26 expands and contracts, the upper bearing case 25 moves up and down with respect to the lower bearing case 15, and further, the elevating ring 28 can move up and down along the guide rod 30 via the bearing 27.

A clamp member 31 curved inside the elevating ring 28 so as to be located between the projecting portions 29 is provided.
Is provided, and the elevating ring 2 is
8. The parallel link mechanism 32 is composed of two parallel links 33 erected at a predetermined angle between the lifting ring 28 and each of the clamp members 31.
A connection link 34 is provided between the support ring 21 and each of the clamp members 31. In this embodiment, two parallel link mechanisms 3 are provided for one clamp member 31.
Although two and three connection links 34 are provided, the number thereof may be appropriately set according to the size of the clamp member 31.

Therefore, when the above-described clamp cylinder 26 is extended, the elevating ring 28 is raised via the upper bearing case 25, whereby each parallel link 33 of the parallel link mechanism 32 is rotated and held by the connecting link 34. The clamp members 31 are moved inward, and the clamp members 31 are moved.
Thereby, the outer periphery of the casing tube T can be held. When the hydraulic motor 23 is driven, the clamp member 31 pivots via the support ring 21, the elevating ring 28, and the parallel link mechanism 32.
The casing tube T held by 1 can be turned.

When the turning force of the hydraulic motor 23 is transmitted from the elevating ring 28 to the clamp member 31, each projection 27 of the elevating ring 28 presses the side surface of each clamp member 31, so that a parallel link mechanism 32 is formed. To reduce the lateral stress acting on the

Here, a shaft excavation operation using the all-casing excavator of the present embodiment will be described.

First, as shown in FIG. 1, the all-casing excavator 10 is lifted and moved by a crane device (not shown), and is positioned on the ground where the shaft is excavated. At this time, as shown in FIG. 5, the push-pull elevating lifting cylinder 16 is extended to raise the lower bearing case 15, and the clamp cylinder 26 is contracted to release each clamp member 31 via each parallel link mechanism 32. Move it towards you. On the other hand, the casing tube (first tube) is lifted and moved by the crane device, and inserted into the all-casing excavator 10. Then, as shown in FIG. 6, the clamp cylinders 26 are extended in synchronization with each other, and the lift ring 28 is extended via the upper bearing case 25.
, The parallel link 33 of each parallel link mechanism 32 is rotated, and each clamp member 31 held by the connection link 34 is moved inward, and the outer periphery of the casing tube T is moved by the four clamp members 31. Hold.

When the casing tube T is held in this manner, the hydraulic motor 23 is driven to rotate the casing tube T held by the clamp member 31 via the support ring 21, the elevating ring 28, and the parallel link mechanism 32. Then, when each push-pull elevating cylinder 16 is contracted in the turning state of the casing tube T, the casing tube T is pushed into the ground while turning, and the ground is cut by the cutter bit at the lower end. At this time, the earth and sand in the casing tube T are discharged by a glove bucket by operating a crane (not shown) to form a shaft.

As described above, in the all-casing excavator of this embodiment, the lower bearing case 15 is supported on the base frame 11 by the push-pull elevating cylinder 16 so as to be able to move up and down.
Is supported by a hydraulic motor 23 so as to be pivotable, while the upper bearing case 25 is supported by a clamp cylinder 26 above and below the lower bearing case 15 so as to be able to move up and down. The clamp member 31 is connected to the ring 28 via a parallel link mechanism 32, and the clamp member 31 is connected to the support ring 21 via a connection link 34.

Therefore, the upper bearing case 25 and the elevating ring 28 are raised by the clamp cylinder 26 to operate the parallel link mechanism 32, so that the outer periphery of the casing tube T is held while the clamp member 31 is stopped. The operation of the hydraulic pump, the switching valve, and the like becomes unnecessary, and the workability can be improved. Further, the clamp member 31 does not come into sliding contact with the casing tube T, thereby preventing damage to the clamp member 31 and the casing tube and improving the durability.

Further, since the clamp cylinder 26 is provided on the fixed side (the bearing cases 15 and 25) along the vertical direction, piping for supplying and discharging hydraulic pressure as a working fluid is facilitated, and the apparatus is downsized. it can.

In the above-described embodiment, the ring gear 22 is fixed to the lower bearing case 15 and the support ring 21 is pivotably supported.
The lifting ring 28 is pivotally supported on the lifting ring 5, 25, and the clamp member 3 is connected to the lifting ring 28 via a parallel link mechanism 32.
1 and connecting link 34 to support ring 21.
, The support ring 21 is pivotably supported by the lower bearing case 15, the ring gear 22 is fixed to the upper bearing cases 15, 25, and the elevating ring 28 is pivotably supported by the support member 15. The clamp member 31 may be connected to the ring 21 via a parallel link mechanism 32, and the clamp member 31 may be connected to the elevating ring 28 via a connection link 34.

In the parallel link mechanism 32,
If the clamp member 31 is supported movably in the radial direction with respect to the elevating ring, the connecting link 34 may be omitted. Further, the parallel link 33 is disposed in a downward direction toward the inside, the lower portion abuts on the lower bearing case 15, and the clamp member 31 is moved inward by the lowering of the elevating ring 28 due to the contraction of the clamp cylinder 26 to move the casing inward. The tube T may be clamped.

[0028]

As described in detail in the above embodiment, according to the shaft excavator of the first aspect of the present invention, the first casing is supported on the base frame by the lifting cylinder so as to be able to move up and down. A second casing is disposed above or below, a clamp cylinder is erected between the two casings, and an elevating ring can be driven to rotate by a driving means in the second casing, and a casing tube is connected to the elevating ring via a parallel link mechanism. Since the clamp member that can hold the outer circumference is connected, the upper bearing case and the elevating ring are raised by the clamp cylinder to operate the parallel link mechanism, so that the outer circumference of the casing tube is held while the clamp member is stopped. To improve reliability by properly clamping without damaging the casing tube Is possible, the operation such as a hydraulic pump or switching valve becomes unnecessary, thereby simplifying and downsizing the structure.

According to the shaft excavator of the second aspect of the present invention, the first casing supports the support ring so as to be pivotable, and the support ring supports the elevating ring so as to be able to move up and down. Since the clamp members are connected to each other, by regulating the posture of the clamp members, it is possible to reliably clamp the casing tube and improve reliability.

According to the shaft excavator according to the third aspect of the present invention, the clamp member is divided into a plurality in the circumferential direction, and the protrusion of the lifting ring is extended between the plurality of clamp members. By transmitting the power to the clamp member via the protruding portion and appropriately turning the casing tube, it is possible to prevent the rotational power of the elevating ring from excessively acting on the parallel link mechanism.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of an all-casing excavator as a shaft excavator according to an embodiment of the present invention.

FIG. 2 is a plan view of the all-casing excavator.

FIG. 3 is an external view of an all-casing excavator.

FIG. 4 is a schematic sectional view of a clamp mechanism.

FIG. 5 is a schematic diagram illustrating an operation of a clamp mechanism.

FIG. 6 is a schematic diagram illustrating an operation of a clamp mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 All casing excavator (vertical excavator) 11 Base plate 13 Leveling cylinder 15 Lower bearing case (1st casing) 16 Lifting cylinder for pushing and pulling 21 Support ring 23 Hydraulic motor (drive means) 25 Upper bearing case (2nd casing) 26 Clamp Cylinder 28 Elevating ring 29 Projection 30 Guide rod 31 Clamp member 32 Parallel link mechanism 33 Parallel link 34 Connection link T Casing tube

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Kunihiko Hori 1-1-1 Wadazakicho, Hyogo-ku, Kobe-shi, Hyogo F-term in MHI Underground Construction Equipment Engineering (reference) 2D029 DC01 PA07 PA07 PB05 PC01 PD04 2D050 AA07 CB22 CB23 EE04

Claims (3)

[Claims] 1. A base frame installed at a predetermined position, a first casing supported on the base frame by a lifting cylinder so as to be able to move up and down, and a second casing disposed above or below the first casing. A clamp cylinder erected between the second casing and the first casing, an elevating ring rotatably supported by the second casing, a drive means for driving the elevating ring to pivot, A shaft excavator comprising a clamp member connected to a ring via a parallel link mechanism and capable of holding an outer periphery of a casing tube. 2. The shaft excavator according to claim 1, wherein a support ring is rotatably supported on the first casing, and the elevating ring is supported on the support ring so as to be vertically movable, and a connecting link is connected to the support ring. A shaft excavator, wherein the clamp member is connected via a shaft. 3. The shaft excavator according to claim 1, wherein the clamp member is provided in a plurality of pieces in a circumferential direction, and a projecting portion of the elevating ring extends between the plurality of clamp members. A shaft excavator characterized by the following.