JP2009144469A - Excavating blade expansion/contraction device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device wherein an excavating blade can reliably expanded/contracted and a repair/maintenance work can easily be done while the expanded/contracted state of the excavating blade can easily be checked above the ground. <P>SOLUTION: The device is composed of an expansion/contraction operating part 30 provided on an upper portion of a rotating shaft 11, a pair of connection rods 19 disposed on the outer side of the rotating shaft 11 and operated to be moved up and down by actuation of the expansion/contraction operating part 30 and an excavating blade 16 connected to a lower end of the respective connection rods 19. The expansion/contraction operating part 30 includes a pair of oil hydraulic cylinders 32 mounted on the outer periphery of the rotating shaft 11 and a synchronizing mechanism (synchronization bracket 35, etc.) for synchronizing the operation of the pair of the oil hydraulic cylinders 32. Also, each connection rod 19 is connected to a tip end of a cylinder rod 33 of the respective oil hydraulic cylinder 32, so as to make respective connection rods 19 simultaneously move up and down. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an excavating blade expanding / contracting device used for constructing a rooted bulb at the tip of an underground pile.

  Conventionally, when excavating the ground using an excavator such as an earth auger, and at the same time injecting chemicals such as cement milk and mortar and kneading with excavated soil, In order to increase, the root part of the pile is dug up and the root bulb is built.

  When constructing this root-clamping bulb, a drilling blade as an enlarged drilling blade is provided at the lower end of the drilling rod supported and rotated along the leader mast in addition to a normal drilling blade. After a predetermined vertical hole is excavated in a state where the diameter of the excavator is reduced, the excavation blade is expanded to perform an expanded excavation.

  As for the expansion / contraction structure of the excavation blade, the excavation rod can be rotated in the forward and reverse directions, the excavation blade is pressed by the earth and sand to reduce the diameter during the forward rotation, and the excavation is performed by the earth and sand entering the tip of the excavation blade during the reverse rotation. In general, the wing is configured to stand up outward and be expanded in diameter.

  Patent Document 1 proposes an excavating blade expanded and contracted by an operating rod provided so as to penetrate the excavating rod. That is, in the one described in this document, the expansion excavation blade (excavation blade) is pivotally attached to the support portion at the lower end of the excavation rod by the spring so that it can be rotated freely. The contact portion at the lower end of the operation rod is brought into contact with the upper surface between the front ends of the operation portions, and the right and left enlarged excavation blades are expanded when the operation rod is pulled up.

  However, with a structure that expands and contracts the excavation blade by rotating the excavation rod forward and backward and utilizing the resistance of the earth and sand, depending on the soil, the sand does not enter the tip of the excavation blade, and the diameter cannot be expanded reliably. There is a problem that the diameter cannot be increased to an arbitrary diameter, and the state of expansion / contraction of the excavating blade cannot be confirmed.

  Further, in the structure described in Patent Document 1, since the expansive habit is given by a spring, the excavation blade is not surely expanded depending on the soil, or the expansion / contraction state of the excavation blade is There is a problem that it cannot be confirmed. In addition, since the operating rod and the expansion / contraction mechanism are confined in the internal space of the excavation rod, etc., the mechanism can be used when the expansion / contraction mechanism, etc. fails and needs to be repaired, or when maintenance is required. There is a problem that it must be disassembled and cannot be easily repaired.

Japanese Patent No. 3626647

  The present invention has been made in view of the above-described problems, and can perform the expanding / contracting operation of the excavating blade reliably, and can easily perform repair and maintenance work, and further, the expanded / contracted state of the excavating blade An object of the present invention is to provide a drilling blade expansion / contraction device that can be easily confirmed on the ground.

In order to achieve the above object, a drilling blade expansion / contraction device according to the present invention comprises:
In the excavation blade expansion / contraction device that expands / contracts the excavation blade provided at the lower end of the rotary shaft that is rotationally driven by the drive unit,
An expansion / contraction operation part provided at the upper part of the rotation shaft, a pair of connecting rods arranged on the outer side of the rotation shaft and operated to move up and down by the operation of the expansion / contraction operation part, and excavation connected to the lower end of each connection rod With wings,
The expansion / contraction operation part has a pair of hydraulic cylinders attached to the outer peripheral surface of the rotating shaft, and a tuning mechanism part for synchronizing the operation of the pair of hydraulic cylinders, and the connecting rods at the cylinder rod ends of the hydraulic cylinders The connecting rods are configured to be moved up and down at the same time by being connected.

  In the present invention, it is preferable that a spiral blade is provided on the outer peripheral surface of the rotating shaft, and the connecting rod is disposed so as to penetrate the spiral blade.

  Further, the excavating blade expanding / contracting device according to the present invention may be configured such that the excavating blade expands when the connecting rod is pushed down, or the excavating blade expands when the connecting rod is pulled up. It can also be configured to be actuated.

  In the present invention, when the pair of hydraulic cylinders in the expansion / contraction operation unit provided at the upper part of the rotating shaft is operated, the pair of connecting rods connected to the tip of the cylinder rod of the hydraulic cylinder are operated in synchronization with each other, The excavating blade connected to the lower end of each connecting rod is operated from the reduced diameter position to the enlarged diameter position or from the enlarged diameter position to the reduced diameter position. According to the present invention, the excavating blade is expanded / contracted via the connecting rod disposed outside the rotating shaft by the operation of the hydraulic cylinder attached to the outer peripheral surface of the rotating shaft, so that it is disassembled during repair and maintenance work. There is no need, and the operation can be easily performed. In addition, the expansion / contraction operation of the excavation blade can be performed reliably regardless of the soil quality, and the expansion / contraction state of the excavation blade can be easily confirmed on the ground. In addition, since a synchronization mechanism that synchronizes the operation of the pair of hydraulic cylinders is provided, the pair of excavating blades can be operated in a reliable manner.

  In the present invention, when adopting a configuration in which the excavation blades are operated to expand when the connecting rod is pushed down, the excavation blades are rotated and stored downward when the rotary shaft is pulled up. The entire device can be pulled up without breaking the wall of the drilled vertical hole.

  Next, specific embodiments of the excavating blade expansion / contraction device according to the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows an overall view of an earth auger equipped with an excavating blade expansion / contraction device according to a first embodiment of the present invention. FIG. 2 shows a partially enlarged view of the vicinity of the excavating blade in the excavating blade expanding / contracting apparatus of the present embodiment, and FIG. 3 shows a partial enlarged view of the expansion / contraction operation unit in the excavating blade expanding / contracting apparatus. FIG. 4 is a partially enlarged view of the rotating shaft.

  In the present embodiment, the earth auger 1 includes a leader mast 4 that is supported vertically on a base machine 2 via a stay 3, and a drive unit 6 is moved up and down on a guide rail 5 disposed on the front surface of the leader mast 4. A wire 8 that is slidably supported and wound around a sheave 7 at the top of the drive unit 6 is guided to a winch 10 on the base machine 2 via a sheave 9 at the upper end of the leader mast 4. The drive unit 6 is moved up and down along the guide rail 5 by winding and unwinding. Although not clearly shown in the figure, an electric motor and a speed reducer, and a swivel for injecting a chemical liquid such as cement milk and mortar are mounted in the drive unit 6, and an auger screw rotates on the output shaft of the speed reducer. The upper end of the shaft 11 is connected. Thus, the rotating shaft 11 is rotationally driven by the driving of the electric motor in the driving unit 6.

  The rotating shaft 11 is formed by connecting shafts having a unit length by a male joint 12 and a female joint 13. A spiral blade (screw) 14 is provided on the outer peripheral surface of the rotary shaft 11, a tip bit 15 is provided at the lowermost end, and a pair of left and right excavation blades 16 is provided above the tip bit 15. Yes. As shown in FIG. 2, the excavating blade 16 expands / contracts between an enlarged diameter position (solid line position) projecting laterally and a reduced diameter position (chain line position) stored within the diameter of the spiral blade 14. It is configured freely.

  Each of the excavating blades 16 has a base end portion bent in a “K” shape, and a large number of bits 16 a are attached to the tip end portion. 11 is pivotally attached to the support bracket 17 attached to 11 and is pivotally attached to the connecting rod 19 at the base end portion. Thus, the excavating blade 16 is in a reduced diameter position within the diameter of the spiral blade 14 when the connecting rod 19 is pulled upward, and when the connecting rod 19 is pushed down, the tip portion is centered on the pivot 18. It is lifted and rotated to the enlarged diameter position. A stopper 20 is provided on the outer peripheral side upper portion of the support bracket 17, and when the excavating blade 16 reaches a predetermined maximum diameter expansion position, the stopper 20 is brought into contact with and held in position. In the present embodiment, the excavating blade 16 can be expanded to about twice the shaft diameter.

  Next, the detailed structure of the expansion / contraction operation unit 30 for performing the expansion / contraction operation of the excavating blade 16 will be described with reference to FIG.

  The expansion / contraction operation unit 30 includes a pair of left and right hydraulic cylinders 32, 32 supported on the outer peripheral surface of the rotating shaft 11 via a mounting bracket 31, and is attached to the distal ends of the cylinder rods 33, 33 of the hydraulic cylinders 32, 32. The upper end portion of the connecting rod 19 is pivotally supported via the connecting pieces 34 and 34. The connecting pieces 34, 34 are integrally provided with a cylindrical tuning bracket 35 disposed so as to hold the outer peripheral portion of the rotating shaft 11. A plurality of concave grooves are formed in the longitudinal direction on the inner peripheral surface of the tuning bracket 35, and each concave groove is fitted to a slide rail 35 </ b> A projecting in the vertical direction on the outer peripheral surface of the rotating shaft 11. It is configured as follows. With such a configuration, when the cylinder rods 33 and 33 are expanded and contracted, the tuning bracket 35 is slid along the rotation shaft 11 without rotating relative to the rotation shaft 11, and the left and right cylinder strokes are made the same. be able to. Note that the tuning bracket 35, the slide rail 35A, and the like in the present embodiment correspond to a tuning mechanism unit in the present invention.

  Pressure oil from a hydraulic source (not shown) is supplied to oil passages 38 and 39, a swivel joint 40, and vice versa at the bottom side supply and discharge ports 36 and 36 and the head side supply and discharge ports 37 and 37 of the hydraulic cylinders 32 and 32. It is supplied and discharged via the stop valve 41. Here, a detent bar 42 is fixed to the outer case 40 a of the swivel joint 40, and the detent bar 42 is fixed to a reaction force body 43 fixed to the leader mast 4. The check valve 41 moves the hydraulic cylinders 32 and 32 when the hydraulic cylinders 32 and 32 are extended and the connecting rods 19 and 19 are pushed down to rotate the excavating blade 16 to the enlarged diameter position. To hold.

  In the expansion / contraction operation unit 30 of the present embodiment, a stroke sensor 44 is attached to the outer peripheral surface of the rotary shaft 11 within the operating range of the cylinder rod 33, and a detection signal of the stroke sensor 44 is transmitted from the sensor wire 45. It is transmitted to a controller (not shown), and the detected data is displayed on a monitor display board in the cab. Therefore, the operator can know at a glance the expansion / contraction state of the excavating blade 16 and the amount of expansion / contraction by looking at the monitor display board.

  In such a configuration, when the cylinder rods 33, 33 of the hydraulic cylinders 32, 32 are contracted, the pressure oil from the hydraulic source passes through the oil passage 38, the swivel joint 40 and the check valve 41, and the hydraulic cylinder 32. , 32 is supplied to the bottom chamber through the bottom side supply / discharge ports 36, 36, and when the pressure oil in the head side chamber is discharged from the head side supply / discharge ports 37, 37, the cylinder rods 33, 33 are moved. The connecting rod 19 is actuated in the push-down direction. Here, as shown in FIG. 4, the connecting rod 19 is arranged so as to pass through the spiral blade 14 provided on the outer peripheral surface of the rotating shaft 11, and the lower end of the connecting rod 19 is the excavating blade as described above. Since the connecting rod 19 is pushed down, the excavating blade 16 is lifted about the pivot shaft 18 and rotated to the enlarged diameter position. In order to reduce the diameter of the excavating blade 16, the pressure oil may be supplied to the head side chamber from the head side supply / discharge ports 37, 37 of the hydraulic cylinders 32, 32.

  The rooting method using the excavating blade expansion / contraction device as described above is performed in the following procedure.

  First, in a state where the diameter of the excavating blade 16 is reduced, a vertical hole is excavated to the support layer. At this time, the excavating blade 16 is accommodated within the diameter of the spiral blade 14 and maintains its reduced diameter position, so that the excavation of the vertical hole by the spiral blade 14 is not hindered.

  When the support layer is reached, the diameter of the excavating blade 16 is increased by operating the hydraulic cylinders 32 and 32, and cement milk, mortar, or the like is injected to build up a rooted bulb. At this time, the enlarged diameter of the excavating blade 16 can be arbitrarily changed by adjusting the cylinder stroke of the hydraulic cylinders 32 and 32.

  When the construction of the root-fixing bulb is completed, the excavation blade 16 is reduced in diameter by the operation of the hydraulic cylinders 32 and 32 and is accommodated within the diameter of the spiral blade 14, and then the rotation shaft 11 is pulled up to complete the construction. In addition, according to the structure of this embodiment, since the excavation blade 16 is turned and stored in the downward direction, the apparatus can be installed without breaking the wall of the excavated vertical hole when the rotary shaft 11 is pulled up. Can be raised.

(Second Embodiment)
FIG. 5 shows a partially enlarged view of the vicinity of the excavating blade in the excavating blade expanding / contracting apparatus according to the second embodiment of the present invention. In the present embodiment, portions common to the first embodiment are given the same reference numerals in the drawing, and detailed description thereof is omitted.

  In the first embodiment, the excavating blade 16 is rotated to the diameter-expanded position when the connecting rod 19 is pushed down. However, in the present embodiment, the excavating blade is moved when the connecting rod 19 is pulled up. A structure is adopted in which 16 is rotated to the enlarged diameter position. In FIG. 5, the right side shows a state where the connecting rod 19 is pulled up, and the left side shows a state where the connecting rod 19 is pushed down. The same effects as those of the first embodiment can be obtained by the structure as in the present embodiment.

  In each of the above-described embodiments, the example in which the spiral blade (screw) 14 is provided on the outer peripheral surface of the rotating shaft 11 has been described. However, as shown in FIG. It can also be applied to those having a stirring rod 47 having a stirring bar 47a attached to the outer periphery as shown in FIG. 6 (b). Of course, the present invention can also be applied to a combination of these shafts.

1 is an overall view of an earth auger equipped with an excavating blade expansion / contraction device according to a first embodiment of the present invention. The partial enlarged view of the excavation blade vicinity in the excavation blade expansion / contraction apparatus of 1st Embodiment The elements on larger scale of the expansion / contraction operation part in the excavation blade expansion / contraction apparatus of 1st Embodiment The partial enlarged view of the rotating shaft in the excavation blade expansion / contraction apparatus of 1st Embodiment The partial enlarged view of the excavation blade vicinity in the excavation blade expansion / contraction apparatus of the 2nd Embodiment of this invention The figure which shows the modification of a rotating shaft

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Earth auger 4 Leader mast 6 Drive part 11 Rotating shaft 12, 13 Joint 14 Spiral blade 15 Tip bit 16 Excavation blade 17 Support bracket 18 Axis 19 Connecting rod 20 Stopper 30 Expansion / contraction operation part 32 Hydraulic cylinder 33 Cylinder rod 35 Tuning bracket 36, 37 Supply / discharge port 40 Swivel joint 41 Check valve 44 Stroke sensor 46 Connecting shaft 47 Stirring rod

Claims (4)

In the excavation blade expansion / contraction device that expands / contracts the excavation blade provided at the lower end of the rotary shaft that is rotationally driven by the drive unit,
An expansion / contraction operation part provided at the upper part of the rotation shaft, a pair of connecting rods arranged on the outer side of the rotation shaft and operated to move up and down by the operation of the expansion / contraction operation part, and excavation connected to the lower end of each connection rod With wings,
The expansion / contraction operation part has a pair of hydraulic cylinders attached to the outer peripheral surface of the rotating shaft, and a tuning mechanism part for synchronizing the operation of the pair of hydraulic cylinders, and the connecting rods at the cylinder rod ends of the hydraulic cylinders The excavating blade expanding / contracting apparatus is characterized in that the connecting rods are simultaneously moved up and down by connecting the two.   The excavating blade expansion / contraction apparatus according to claim 1, wherein a spiral blade is provided on an outer peripheral surface of the rotating shaft, and the connecting rod is disposed so as to penetrate the spiral blade.   The excavating blade expanding / contracting apparatus according to claim 1 or 2, wherein the excavating blade is expanded in diameter when the connecting rod is pushed down.   The excavating blade expanding / contracting apparatus according to claim 1 or 2, wherein the excavating blade is expanded in diameter when the connecting rod is pulled up.

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