JP3718824B2 - Drilling device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a perforating apparatus that perforates while preventing collapse of a hole wall.
[0002]
[Prior art]
As a natural ground reinforcement method in the NATM construction method, a construction method is known in which a long tubular body is inserted into the natural ground in front of the face to reinforce the natural ground. In adopting this construction method, a drilling device equipped with a bit that can be expanded and contracted is used because it is necessary to insert a pipe body at the time of drilling and collect the drilling tool after the drilling is completed. This type of punching device is equipped with drilling rod to be connected to the rock drilling machine body, a drilling bit attached to the tip of the drilling rod, the wing bit provided freely scaled behind the drilling bit, the tube When the body is covered and drilled, the wing bit expands to the outer diameter of the tube, and when the device is recovered, the wing bit is reduced to a diameter that allows the tube to be inserted.
[0003]
The above-described conventional drilling device has the following problems.
<A> The expansion / contraction mechanism of the wing bit is not only complicated and expensive, but also the expansion / contraction mechanism is liable to fail due to impact force.
In some cases, the expansion / contraction mechanism of the wing bit is damaged due to an impact at the time of drilling, and the punching apparatus cannot be removed smoothly.
<B> Since the expansion / contraction mechanism of the wing bit is complicated, it is difficult to secure a sufficient space for discharging the soil between the hole walls and the discharge of the soil is poor.
[0004]
[Problems to be solved by the invention]
It is an object of the present invention to provide a drilling device that can improve the transferability of the rotational motion and the striking motion, and that operates accurately while avoiding the influence of cutting waste.
[0005]
[Means for solving problems]
The present invention provides an intermediate rod that is connected to the tip of a drilling rod and has a plurality of axial grooves that are inclined along the axial direction on the peripheral surface, a tip bit that is connected to the tip of the intermediate rod, and the intermediate rod that cannot rotate. And a sliding cylinder externally slidable in the axial direction, an intermediate bit formed integrally with the sliding cylinder and having a larger excavating diameter behind the tip bit than the tip bit, and a slide cylinder In a drilling device including an expansion / contraction bit having a drilling diameter larger than that of the intermediate bit behind the intermediate bit and slidably fitted in the shaft groove of the intermediate rod, and each circumference of the intermediate rod and the sliding cylinder A plurality of protrusions and engagement grooves are formed on the surface to allow mutual sliding in the axial direction, and the intermediate rods and the end surfaces of the sliding cylinders are engaged with each other in the middle. A feature is that a plurality of protrusions and notches are formed to transmit the rotational movement of the rod to the sliding cylinder. That a punching device.
Further, the present invention is characterized in that a cleaning groove is formed on the bottom surface of the inclined groove, an axial path inside the intermediate rod is communicated with the cleaning groove, and a cleaning fluid can be discharged into the inclined groove at all times. This is a punching device. Furthermore, the present invention is a drilling device characterized in that a wing having a centering function and a soil discharging function is formed at the rear part of the intermediate rod.
[0006]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings.
[0007]
<A> General Description FIGS. 1 to 5 show an example of the punching device 10.
In FIG. 1, reference numeral 20 in the drawing is a tubular body that penetrates into the ground together with the punching device 10, and is a tubular body such as a steel pipe, a resin pipe, or a perforated pipe.
A hollow drilling rod 11 is connected to the tail end of the drilling device 10, and the drilling rod 11 is connected to a boring machine (not shown) so that rotational force and striking force can be applied to the drilling device 10. It has become.
[0008]
<B> Punching device The punching device 10 includes a tip bit 12, an intermediate bit 13 located behind the tip bit 12, and an expansion / contraction bit 14 disposed so as to be expandable / contractible behind the intermediate bit 13.
In these, as shown in FIG. 2, the drilling diameters are set to increase stepwise in the order of the tip bit 12, the intermediate bit 13, and the expansion / contraction bit 14.
The drilling diameter of the tip bit 12 and the intermediate bit 13 is set to be equal to or smaller than the inner diameter of the tube body 20, and the drilling diameter of the expansion / contraction bit 14 is from the maximum diameter substantially equal to the outer diameter of the tube body 20 to the inner diameter of the tube body 20. It is set to expand and contract within the minimum diameter range.
The tip bit 12 shown in FIG. 1 is a known bit such as a cross bit, and is appropriately selected according to the perforated ground.
The tip bit 12 is screwed to one end of an intermediate rod 30 having an axial path 31 via a stopper ring 16, and the movement (rotation and striking) of the drilling rod 11 screwed to the other end of the intermediate rod 30 is the tip bit 12. Is transmitted to.
Further, these drilling rods 11 and intermediate rods 30 are formed with continuous axial paths 15, 31, and water or air supplied from the boring machine side of the drilling rod 11 from the discharge path 17 of the tip bit 12. Can be discharged.
[0009]
<C> Sliding cylinder FIG. 3 shows an assembly drawing of the perforating apparatus 10. An annular rod having a sliding cylinder 40 slidably mounted on the intermediate rod 30 and projecting on the outer peripheral surface of the intermediate rod 30. 32 regulates the return position of the sliding cylinder 40 in the direction opposite to the drilling direction.
The sliding cylinder 40 has a plurality of intermediate bits 13 formed on the end surface in the drilling direction, and a plurality of window holes 41 for inserting expansion / contraction bits are formed along the circumferential direction in the middle of the sliding cylinder 30. .
In addition, a plurality of engagement grooves 43 and discharge grooves 42 are formed along the axial direction on the inner and outer peripheral surfaces of the sliding cylinder 40 excluding the formation positions of the intermediate bit 13 and the window hole 41, respectively. A plurality of notches 44 are formed at the proximal end of the sliding cylinder 40 excluding the position where the groove 42 is formed.
[0010]
<D> Intermediate rod As shown in FIGS. 1 and 3, a large-diameter annular flange 32 is formed in the middle of the outer peripheral surface of the intermediate rod 30.
A plurality of inclined grooves 34 are formed along the axial line on the outer peripheral surface of the intermediate rod 30 on the end bit 12 side from the annular flange 32, and the engaging grooves of the sliding cylinder 40 are interposed between the inclined grooves 34. A plurality of protrusions 38 are formed at positions corresponding to 43.
A plurality of protrusions 39 are formed on the side surface of the annular flange 32 that comes into contact with the sliding cylinder 40 at positions corresponding to the notches 44 of the sliding cylinder 40. (See Figure 5)
Each inclined groove 34 is a groove for accommodating the block-type expansion / contraction bit 14, and is given a certain gradient so that the depth gradually increases from the annular flange 32 toward the tip bit 12. Further, a cleaning groove 35 that is continuous along the inclined groove 34 is recessed on the bottom surface of each inclined groove 34, and the upstream portion of each exclusion groove 35 and the axial path 31 communicate with each other through a connection hole 36. Thus, a part of the water or air in the shaft 31 can be branched and supplied to the entire inclined groove 34. This is to prevent cutting waste and the like from entering the inclined groove 34 and to smoothly slide the expansion / contraction bit 14.
A plurality of spiral wings 37 project from the rear outer peripheral surface of the annular rod 32 of the intermediate rod 30. The wing 37 is a member having both the centering action of the intermediate rod 30 with respect to the pipe body 20 and the discharging action of the cutting waste containing slime, and the protruding length thereof is set to a dimension substantially equal to the inner diameter of the pipe body 20. The wing 37 may be omitted.
Further, a discharge groove 33 continuous along the axial direction is formed in the outer peripheral surface of the annular rod 32 of the intermediate rod 30 so that excavation waste can be discharged to the base end side in cooperation with the discharge groove 42. It has become.
[0011]
<E> Fitting structure of intermediate rod and sliding cylinder The intermediate rod 30 is required to transmit the rotational force to the sliding cylinder 40 while allowing the sliding cylinder 40 to slide.
In order to satisfy this requirement, in the present invention, the first fitting structure for fitting the protrusion 38 of the intermediate rod 30 into the engagement groove 43 of the sliding cylinder 40 and the protrusion 39 of the intermediate rod 30 are arranged on the sliding cylinder 40. Two fitting means of the second fitting structure to be fitted into the notch 44 were combined. If a soft ground such as a sandy layer is excavated, it can be dealt with only by the first fitting structure. However, when excavating a hard ground such as a rock, a large rotational torque and impact force repeatedly act. With only the fitting structure, the fitting portion of the protrusion 38 of the intermediate rod 30 and the engaging groove 43 of the sliding cylinder 40 is worn out early, causes settling, the sliding resistance of the sliding cylinder 40 increases, and the expansion / contraction bit is increased. There is a possibility that the expansion / contraction operation of 14 will be uncertain.
As a method of extending the life of the first fitting structure, a method of increasing the number of protrusions 38 and engagement grooves 43 is conceivable. However, there are restrictions due to the presence of the inclined grooves 34 and the expansion / contraction bits 14, and the design is to increase these. Is difficult.
In view of this point, the present invention combines the first fitting means and the second fitting means so that even if a large rotational torque or impact force is repeatedly applied, the fitting portion is prevented from being loosened or worn, and hitting is performed. A structure capable of efficiently transmitting force and rotational force is provided.
[0012]
<F> Enlargement / reduction bit FIGS. 3 and 4 show the mounting structure of the enlargement / reduction bit 14.
The expansion / contraction bit 14 is composed of a main body portion 14b in which a chip 14a is embedded, and a rectangular hem portion 14c that is formed larger than the main body portion 14b and restricts the escape from the window hole 41. The body portion 14b is inserted into the inclined groove 34 so as to be slidable, and the expansion / contraction bit 14 slides in the inclined groove 34 as the sliding cylinder 40 slides. Thus, the protruding amount of the bit from the window hole 41 is changed. That is, when the sliding cylinder 40 shown in FIG. 1 abuts against the annular flange 32, the protruding amount of the expansion / contraction bit 14 becomes the maximum beyond the diameter of the intermediate bit 13, and conversely, the sliding cylinder 40 slides in the direction of the tip bit 12. As it moves, the expansion / contraction bit 14 is retracted, and the diameter of the expansion / contraction bit 14 is reduced to a value equal to or smaller than the inner diameter of the tubular body 20 at a minimum.
Further, when the front end of the main body portion 14b of the expansion / contraction bit 14 fitted in the inclined groove 34 abuts against the stopper ring 16, the return position of the sliding cylinder 40 in the direction of the distal end bit 12 is restricted.
The fitting structure of the expansion / contraction bit 14 described above is merely an example, and is not limited to this. In short, any fitting structure may be used as long as it can regulate sliding while allowing sliding. Can be adopted.
[0013]
[Action]
Next, the drilling method will be described.
[0014]
<A> Drilling / Insertion of Tube Body FIG. 1 shows the time of drilling. A rotational force and a striking force are applied from the proximal end of the drilling rod 11 inserted into the tube body 20 and air or Start supplying water. At this time, the sliding cylinder 40 is retracted until it comes into contact with the annular flange 32, and the expansion / contraction bit 14 slides to the shallow side of the inclined groove 34 and protrudes to the maximum diameter.
When the striking force is transmitted to the intermediate rod 30, it is transmitted to the sliding cylinder 40 through the side surface of the annular rod 32 including the protrusion 39 and finally transmitted to the intermediate bit 13 and the expansion / contraction bit 14.
When the rotational force is transmitted to the intermediate rod 30, the intermediate rod 30 is efficiently transmitted to the sliding cylinder 40 fitted to the protrusion 38 and the protrusion 39 of the intermediate rod 30 via the engaging groove 43 and the notch 44, respectively. It is transmitted to bit 13 and expansion / contraction bit 14.
As described above, the rotational force and the striking force are efficiently transmitted to each of the bits 12 to 14, and the cross section of the tube body 20 is drilled while sharing the drilling burden with the three types of bits 12 to 14 having different diameters. Become.
On the other hand, a part of the water and air supplied through the axial paths 15 and 31 is discharged to the cleaning groove 35 in the inclined groove 34 through the connection hole 36 and continues to exclude excavation debris that tries to enter the inclined groove 34.
The slimmed excavated waste is taken into the tube body 20 through the discharge grooves 33 and 42 of the sliding cylinder 40 and the intermediate rod 30, and is further discharged to the proximal end side of the tube body 20 by the wings 37.
In this way, the tube body 20 is inserted into the ground in parallel with the drilling operation by the drilling device 10.
[0015]
<B> Recovery of the device When the drilling is performed to a predetermined depth, the tube body 20 of FIG.
Then, as shown in FIG. 6, the expansion / contraction bit 14 slides toward the tip bit 12 side together with the sliding cylinder 40. As the sliding cylinder 40 slides, each expansion / contraction bit 14 inserted into the sliding cylinder 40 moves toward the deep side of the inclined groove 34 so that it gradually retracts into the window hole 41 of the sliding cylinder 40 and expands / contracts. When the bit 14 comes into contact with the stopper ring 16, the expanding / contracting bit 14 is reduced in diameter to the inner diameter of the tube body 20 or less.
In this way, a pulling force is applied to the drilling rod 11 to reduce the diameter of the expansion / contraction bit 14, and the punching device 10 is recovered.
The tube 20 left in the ground is required as a chemical solution injection tube or a fore pile.
[0016]
Second Embodiment of the Invention
The intermediate rod 30 may be replaced by the drilling rod 11.
Further, the fitting structure of the intermediate rod 30 and the sliding cylinder 40 may be reversed in the combination of irregularities.
That is, a protrusion is formed on the sliding cylinder 40, an engagement groove is formed on the intermediate rod 30 side, a protrusion is formed on the sliding cylinder 40, and a notch is formed on the annular rod 32 side of the intermediate rod 30. May be.
[0017]
【The invention's effect】
Since the present invention is as described above, the following effects can be obtained.
<A> Since the intermediate rod and the sliding cylinder are fitted with two types of fitting means, these fittings can be reliably carried out without causing wear or settling even if a large rotational force or striking force is applied. Because the movement of the device can be transmitted, the durability of the device is improved.
<B> Since the cleaning groove can be provided in the inclined groove to prevent the drilling waste from entering, the sliding of the expansion / contraction bit becomes smooth and the expansion / contraction of the expansion / contraction bit can be surely performed.
<C> Centering can be achieved at the time of drilling by the wing provided on the intermediate rod, and the soil removal performance is improved.
[Brief description of the drawings]
1 is a longitudinal sectional view of a drilling device. FIG. 2 is a sectional view taken along II-II in FIG. 1. FIG. 3 is an exploded view of the drilling device. FIG. 4 is a sectional view of IV-IV in FIG. Partial enlarged view of the fitting part of the intermediate rod and the sliding cylinder [Fig. 6] Longitudinal sectional view of the punching device when the diameter of the expansion / contraction bit is reduced [Explanation of symbols]
10 drilling device, 11 drilling rod, 12 tip bit,
13 intermediate bits, 14 expansion / contraction bits, 15 axes, 20 pipes,
30 intermediate rod, 31 axial path, 32 annular rod, 33 discharge groove.
34 inclined grooves, 35 cleaning grooves, 36 connection holes, 37 wings,
38 protrusions, 39 protrusions, 40 sliding cylinders, 41 window holes,
42 discharge groove, 43 engagement groove, 44 notch,

Claims (3)

An intermediate rod connected to the tip of the drilling rod and provided with a plurality of shaft grooves inclined along the axial direction on the peripheral surface, a tip bit connected to the tip of the intermediate rod, and the intermediate rod cannot be rotated and axially A sliding cylinder externally slidable, an intermediate bit formed integrally with the sliding cylinder and having a larger excavating diameter behind the tip bit than the tip bit, and an intermediate rod inserted through the sliding cylinder In a drilling device provided with an expansion / contraction bit having a drilling diameter larger than the intermediate bit behind the intermediate bit and slidably fitted in the shaft groove of
On each peripheral surface of the intermediate rod and the sliding cylinder, a plurality of protrusions and engagement grooves that are fitted with each other and allow axial sliding are formed, and
The annular rod of the intermediate rod and the end surface of the sliding cylinder are respectively formed with a plurality of protrusions and notches that are fitted together to transmit the rotational movement of the intermediate rod to the sliding cylinder.
Drilling device. 2. The cleaning groove according to claim 1, wherein a cleaning groove is formed on a bottom surface of the inclined groove, an axial path inside the intermediate rod is communicated with the cleaning groove, and a cleaning fluid can be always discharged into the inclined groove. A perforating device. The piercing device according to claim 1 or 2, wherein a wing having a centering function and a soil discharging function is formed at a rear portion of the intermediate rod.

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