JP2013124535A - Excavation apparatus and method for forming underground heat exchanger installation hole - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an excavation hole at high speed by adding an excavation function to a casing to improve excavation efficiency and prevent collapse of a hole wall.SOLUTION: An excavation apparatus for forming an underground heat exchanger installation hole is provided with a ring bit 10 at the underground-side end side of a hollow casing 7 rotationally driven by rotational drive means 5, thereby enabling stable excavation of a large hole. An air hammer device 8 which has a hammer bit 9 at the end, is arranged with a weight for suppressing the spring-up of a hammer at the top, and causes a downward impact is installed inside the casing 7. A connection part 16 is provided which can engage and disengage the casing 7 with and from the air hammer device 8, and excavation for forming the underground heat exchanger installation hole is performed by the integral movement of the casing 7 and the air hammer device 8.

Description

  The present invention relates to an excavation apparatus and an excavation method for providing an underground heat exchanger in the ground of a ground such as a residential area. More specifically, the present invention relates to an excavation apparatus and an excavation method for excavation for forming a ground heat exchanger installation hole by integrating a casing and an air hammer device on a ground such as a residential area.

  Geothermal heat is already used in various fields because the temperature is constant throughout the year. In order to use this underground heat, it is necessary to excavate a hole in the ground. In general, excavation work has been conventionally performed on many grounds including grounds such as residential areas and building construction areas. For example, as a method of forming a pile, a method has been proposed and implemented in which a mortar or concrete is poured into a drilled hole and hardened to form a foundation pile or the like. In addition, excavation is carried out using a drilling device for a well.

  In general, as a simple excavation method, concrete or the like is poured directly into the excavated hole and hardened to make a foundation pile, or the excavated hole itself is used as a well, but if the ground is soft There is a drawback that a stable excavation hole is not formed. For these reasons, recently, a double-pipe excavation method especially considering soft ground has attracted attention and many proposals have been made. In this method, excavation is performed by providing a casing on the outer periphery of the excavator.

  That is, even after excavation, the casing is temporarily left on the ground to maintain the hole shape, and the excavation hole is formed. Thereby, collapse of the wall surface of a hole can be prevented even after digging, and a digging hole having a stable shape can be formed. For example, it has a casing on the outside, hitting with an air hammer and simultaneously rotating a bit provided at the bottom, and after excavation, pulls only the bit device upward and leaves only the casing in the ground. There is known a technique for forming a foundation pile or the like by filling concrete or the like (see, for example, Patent Document 1). The casing of this example has only a function of preventing collapse of the wall surface of the excavation hole.

  In addition, the air hammer device is built inside the casing for excavation, and the hammer device is lifted through the winch by using the overshot head after opening the latch with the casing left. There is known an example in which an object is applied to burial work such as an anchor bolt (see, for example, Patent Document 2).

  In addition, it is an example of drilling the underground installation work of a heat exchanger for recovering geothermal energy, but an example is disclosed in which a crane truck is used, suspended by a wire, and excavated by attaching a vibro hammer to the upper part of the hollow tube. (For example, see Patent Document 3). In this excavation method, excavation is performed using an air-water jet, and when a predetermined depth is reached, a hollow tube is pulled out and a heat exchanger is embedded. Although this excavation method uses a hollow tube, it is not a double tube method in which a so-called hollow tube is embedded. Also in this excavation method, the hollow tube itself does not have an excavation function.

  This construction method is excavation for installing an underground heat exchanger, but the cost of the facilities is increased by providing an air-water jet supply device. Further, a system that combines a drilling rod and a heat exchanging pipe is also known, but this excavation method also excavates the ground with a jet jet to form a heat exchanging well (for example, see Patent Document 4). Further, as a method for embedding a ground heat exchanger in an excavated hole, a method for embedding U-tubes in an overlapping manner has been proposed (see, for example, Patent Document 5).

  Furthermore, a drilling device for down-the-hole hammer is disclosed, but it is inserted into the steel pipe pile, and a rod composed of an outer cylinder and an inner cylinder is provided on the upper part of the air hammer, and the inner cylinder is relatively moved up and down. It is configured to be movable (see, for example, Patent Document 6). The excavator in this example is disclosed as a technique for excavating by being inserted into a steel pipe pile.

  As described above, most of the double-pipe type excavators have an excavator inside the casing and excavate with a bit at the end of the excavator. The outer casing has a function of preventing the ground collapse of the excavation hole. For this reason, in the case of soft ground, the casing is pushed in by an excavator with vibration such as a hammer device. In this case, the excavation efficiency is improved by excavating the ground directly below the excavation direction of the casing with the excavator in the casing. For example, in the above-described conventional technique, the internal excavation is performed in the excavation process as shown in Patent Document 1. A part of the equipment bit is expanded and drilled. In this example, the air hammer device is a device that performs excavation by rotating and applying vibration with air. This complicates the configuration and increases the cost.

  When excavating with the double pipe method in this way, excavation is performed while the entire excavator including the casing is buried in the ground, but after excavation, the casing is hollowed and only the excavator is first lifted to the ground. Has been done. Although it may remain as it is after excavation in the ground like a steel pipe pile, in the case of pile installation or a well, the casing must be collected later on the ground. A conventional casing embedding method is a method of pushing into the ground while being pushed by an excavator.

JP-A-10-266197 JP-A-7-3787 JP 2003-82970 A JP 2004-20017 A JP 2001-174073 A JP 2007-314959 A

  As described above, the function of the conventional casing is only to prevent the excavation hole from collapsing. The casing itself did not have a drilling function. As described above, it is possible to install the underground heat exchanger in the excavation hole made by the conventional technique, but the excavation cost is expensive. In particular, since the underground heat exchanger embeds a pipe structure (for example, a U tube) constituting the underground heat exchanger, a hole having a certain size is required.

  For this reason, the casing becomes large, but in the case of conventional casing driving, the casing itself is pushed by the excavator, so that the pushing resistance of the casing is increased and excavation is not stable. Moreover, when the underground heat exchanger is installed as a residential system, it is required to be as simple as possible and reduced in cost. The present invention has been made to solve the above-described problems, and achieves the following object.

It is an object of the present invention to form a ground heat exchanger installation hole that allows a casing to have a drilling function to increase excavation efficiency and at the same time prevent collapse of a drilling hole and embed a ground heat exchanger. It is in providing the drilling apparatus and its drilling method.
Another object of the present invention is to provide a simple coupling part that can be engaged and disengaged between a casing and an air hammer device inserted therein, and the air hammer device is detached from the casing and can be easily lifted to the ground. An object of the present invention is to provide a drilling device and a drilling method for forming an underground heat exchanger installation hole.

The present invention takes the following means in order to achieve the object.
The excavation apparatus for forming the underground heat exchanger installation hole of the present invention 1
An air hammer device that has a hammer bit at the lower end and a weight to prevent the hammer from jumping up and generates a downward hit in a hollow casing that is rotationally driven by a rotational drive means. In the excavating apparatus for excavating the underground heat exchanger installation hole, the ring bit disposed at the lower end of the casing on the underground side and installed in accordance with the installation site of the hammer bit, the casing, and the air It is provided across the hammer device, and includes a coupling portion that is coupled to perform excavation of the underground heat exchanger installation hole by the integral operation of the casing and the air hammer device.

The excavation apparatus for forming the underground heat exchanger installation hole of the present invention 2 in the present invention 1,
The coupling portion includes a first coupling portion provided in the casing inner diameter portion, and a second coupling portion provided in an outer diameter portion of the air hammer device and freely abutted against the first coupling portion, Both the casing and the air hammer device can rotate integrally, and the relative movement in the vertical direction is constrained when they are abutted by relative movement in the rotational direction, and the relative movement in the vertical direction is possible when the abutment is released. It is the structure.

The excavation apparatus for forming the underground heat exchanger installation hole of the present invention 3 in the present invention 1,
The coupling part includes a first coupling part provided on the casing inner diameter part, and a second coupling part provided on an outer diameter part of the air hammer device and protruding and coupled to the first coupling part, The casing and the air hammer device can be rotated together, and the relative movement in the vertical direction is restricted when the second coupling part protrudes, and the relative movement in the vertical direction is possible when the second coupling part is retracted. It is characterized by being.

Excavation apparatus for formation of underground heat exchanger installation hole of the present invention 4 in the present invention 1 to 3,
The casing and the air hammer device are characterized in that excavation is performed by an elevating drive means and a rotary drive means installed in a leader of an excavating machine.
Excavation apparatus for formation of underground heat exchanger installation hole of the present invention 5 in the present invention 1 to 4,
The ring bit is configured to be attached to the casing via a support member.

Excavation apparatus for formation of underground heat exchanger installation hole of the present invention 6 in the present invention 1 to 5,
The ring bit is configured to be movable along the excavation direction of the casing with respect to the support member.
Excavation apparatus for ground heat exchanger installation hole formation of the present invention 7 in the present invention 1 to 6,
The air hammer device is lifted away from the casing by driving an elevating drive means of the excavating machine via a detachable engaging member when the first coupling portion and the second coupling portion are detached. It is the structure.

The drilling device for forming the underground heat exchanger installation hole of the present invention 8 according to the present invention 1 to 6,
The rotation driving means is provided on a guide stand that is movable with respect to the leader of the excavating machine.

The excavation apparatus for underground heat exchanger installation hole formation of the present invention 9 in the present invention 1 to 6,
The casing is configured to be pulled up by a lifting / lowering driving means of the excavating machine via a gripping portion on the rotation driving means side.

The excavation method for forming the underground heat exchanger installation hole of the present invention 10 is,
In the hollow casing that can be rotated by the rotation drive means, an air hammer device that has a hammer bit at its end and places a weight on the upper part to suppress the hammer's jumping and generates a downward hit is provided, In the excavation method for excavating a ground heat exchanger installation hole, an air hammer device having a hammer bit at an end portion is inserted into the casing, and a ring bit is fixed to the casing end; and provided in the casing The first coupling portion and the second coupling portion provided in the air hammer device are coupled and integrated, and the air hammer device is struck while rotating the casing in one direction, and the ring bit And drilling to a predetermined depth in the ground with the hammer bit, and after digging to a predetermined depth, the casing The step of releasing the coupling of the air hammer device and lifting the air hammer device to the ground, the step of inserting and burying a ground heat exchanger in the casing, the step of lifting the casing to the ground, and exchanging the ground heat And installing the vessel in the excavation hole.

  The excavation apparatus and the excavation method for forming an underground heat exchanger installation hole according to the present invention have a configuration in which a bit is provided in a casing, and the excavation efficiency can be increased by providing an excavation capability on the casing side. Since the excavation method is to pull up the casing after installing the underground heat exchanger, the underground heat exchanger can be buried by preventing the excavation hole from collapsing. In addition, a simple coupling part that can be engaged and disengaged is provided between the casing and the air hammer device provided inside, and the installation hole for the underground heat exchanger can be formed by excavating in the coupled state, and after the excavation is completed, the coupling is performed. The air hammer device was lifted to the ground so that it could be recovered. In addition, excavation can be performed using the functions and equipment of an excavating machine having a leader, so that excavation efficiency can be improved.

The excavation apparatus and the excavation method for forming a geothermal heat exchanger installation hole according to the present invention can install the geothermal heat exchanger at a low price, use natural energy, and regenerate with low CO ₂ emissions. It is possible to contribute to the spread of the geothermal heat pump system, which is expected as one of the possible energies. Moreover, since this excavation apparatus and its excavation method can be applied to a geothermal heat pump system for ordinary houses, this aspect can also contribute to widespread use.

FIG. 1 is an explanatory view schematically showing a house provided with a geothermal heat pump system in which a geothermal heat exchanger is buried in a geothermal heat exchanger installation hole excavated by the excavator of the present invention. FIG. 2 is an overall view of an excavating machine incorporating the excavator of the present invention. FIG. 3 is a cross-sectional view showing details of the excavator. 4 is a cross-sectional view taken along line AA in FIG. 5 is a cross-sectional view taken along the line BB in FIG. (A) shows the configuration when the rod and the air hammer device are coupled, and (B) shows the configuration when the coupling between the rod and the air hammer device is released. 6 is a cross-sectional view taken along the line CC of FIG. FIG. 7 is a process diagram showing a state immediately before the casing is put on the air hammer device installed on the ground with the ring bit fitted in the lower part. FIG. 8 is a process diagram showing a state where a casing is put on the air hammer device. FIG. 9 is a process diagram showing a state where the excavator has excavated to a predetermined depth. FIG. 10 is a process diagram showing a state in which the uncoupled motor is retracted from the casing. FIG. 11 is a process diagram showing a state in which the overshot head is suspended in the casing via the wire and engaged with the engaging portion of the air hammer device. FIG. 12 is a process diagram showing a state where the air hammer device is lifted from the casing to the ground. FIG. 13 is a process diagram showing a state in which the underground heat exchanger is inserted into the underground casing. FIG. 14 is a process diagram showing a state in which the underground heat exchanger is buried in the excavated underground heat exchanger installation hole. FIG. 15 is a cross-sectional view of a drilling rig showing another embodiment. 16 is a cross-sectional view taken along the line DD of FIG. 17 is a cross-sectional view taken along line EE in FIG. (A) shows the configuration at the time of coupling, and (B) shows the configuration at the time of coupling release.

  Embodiments of an apparatus relating to the present invention will be described in detail with reference to the drawings. The present invention relates to a drilling device and a drilling method for forming a ground heat exchanger installation hole in which a ground heat exchanger is buried in the ground. As described above, utilization of geothermal heat has various application examples, but this embodiment will be described by applying it to a single-family home. FIG. 1 is an explanatory view schematically showing a house having a geothermal heat pump system in which a geothermal heat exchanger is embedded in a geothermal heat exchanger installation hole in a residential site excavated by the excavator of the present invention. is there.

  The geothermal heat pump system Y is buried in the ground and used as a ground heat exchanger for exchanging heat with the ground. The heat collected by the ground heat exchanger is used as a heat source for further high or low temperature heat. The heat pump P for generating the heat, and the heat load portion for performing cooling and heating, snow melting and the like using the heat generated by the heat pump P as a heat source. The underground heat exchange pipe U, which is an underground heat exchanger, is embedded in a grout Gr filled in an excavated underground heat exchanger installation hole (hereinafter referred to as an excavation hole) X. In the primary side heat medium flow path including the underground heat exchange pipe U, the primary side circulating fluid circulates, and heat exchange with the underground is performed to collect and dissipate underground heat. . The underground heat exchange pipe U buried in the excavated excavation hole X is made of a U tube made of resin (for example, polyethylene), a stainless steel pipe, or the like. The primary side circulating fluid circulates in the primary side heat medium flow path including the underground heat exchange pipe U by the action of a pump (not shown).

  The temperature in the ground is at a constant temperature of 10 to 15 ° C., which is almost constant throughout the year. The heat pump P uses the primary-side circulating fluid that exchanges heat with the ground as a heat source, and generates thermal energy that is higher than that of the primary-side circulating fluid in winter and cold energy that is lower than the temperature of the primary-side circulating fluid in summer. The generated cooling energy or heating energy is sent to a cooling / heating device, a hot water supply device, or the like via a secondary circulating fluid that circulates through the secondary heat medium flow path Z. For example, in a general household, a floor heating circulation channel FH, a fan coil unit FC, and a hot water supply device HW are arranged as shown in FIG. 1, and the cold energy or hot energy is used for room cooling and heating, hot water supply, and the like. .

  In the winter season, it is effective for the thermal energy of heating by the fan coil unit FC, floor heating FH, panel heater or the like. In summer, it is effective for cooling by the fan coil unit FC or the like. This heat pump P is a well-known thing comprised from a primary side heat exchange part, a secondary side heat exchange part, a compression part (compressor), an expansion part (expansion valve), etc. In the heat pump P, the primary heat exchange section is an evaporator in the heating cycle, the secondary heat exchange section is a condenser, and in the cooling cycle, the primary heat exchange section is a condenser, and the secondary heat exchange section is an evaporator. It becomes. In Japan, the use of such geothermal natural energy for ordinary houses is not widespread due to the high cost of drilling the excavation hole X and the like. In particular, the ground heat pump system Y for general households must be simple and capable of excavating the installation hole for the ground heat exchanger at low cost. The present invention provides an excavation apparatus and an excavation method for solving this problem. Next, a drilling device that drills a hole for installing a ground heat exchanger and its drilling technology will be described with reference to FIGS.

  There are various forms of forming the excavation hole X, but in the present embodiment, a description will be given as an apparatus for excavating by a double-pipe excavation method using a casing. Since the excavation of the excavation hole X for installing the underground heat exchanger is performed by a leader type excavation machine, first, the basic structure of this machine will be described with reference to FIG. This excavating machine 1 is widely used for ground improvement and the like, and since this embodiment is particularly intended for the ground in residential areas, it is a relatively small excavating machine. The excavating machine 1 can move by itself to an arbitrary position with a crawler. When the excavating machine 1 reaches a predetermined position and starts excavation work, the leader 2 is driven vertically by driving the hydraulic cylinder 3.

  The leader 2 is provided with a guide base 4, and the guide base 4 is movable on the leader 2 in the vertical direction. Usually, the guide 4 is moved through a chain driven by a rotation operation of a feed hydraulic motor provided in the excavating machine 1. The raising and lowering drive means is constituted by a feed hydraulic motor, a chain and the like. The guide 4 is provided with a motor (rotation drive means) 5 for rotating the casing 7. A support 6 for supporting the casing 7 below is provided below the leader 2. Although not shown, a compressed air supply device for supplying compressed air is provided in the vicinity of the excavating machine 1.

  The excavating machine 1 has such a configuration, and the casing 7 is gripped by a gripping portion which is a chuck provided in the motor 5 during excavation. The casing 7 is moved in the vertical direction via a feed hydraulic motor serving as an elevating drive means and a guide base 4 linearly driven by a chain, and is rotationally driven by a built-in motor 5. FIG. 3 is a cross-sectional view showing details of the excavator. As shown in FIG. 3, an air hammer device 8 that performs excavation by air impact is provided separately, and is configured to be inserted into the hollow portion of the casing 7. A hammer bit 9 is fixedly disposed at the lower end of the air hammer device 8.

  The air hammer device 8 is configured to receive compressed air from the compressed air supply device from above as shown by an arrow in FIG. That is, the air hammer device 8 performs excavation by transmitting a hammering action of a piston operated by compressed air to the hammer bit 9. Since the structure and function of the air hammer device 8 are known, detailed description thereof is omitted in the present embodiment. A weight 8w for suppressing the hammer bit 9 from jumping up is disposed on the air hammer device 8. A ring bit 10 is attached to the lower end of the casing 7. The ring bit 10 is integrated with the casing 7, and the casing 7 itself has a drilling function.

  As described above, the excavation apparatus according to the present embodiment is mainly configured with the casing 7 and the air hammer apparatus 8 as the center, and the details thereof have a structure shown in FIG. The casing 7 is configured to be able to be added by screw fastening when the depth is increased by a hollow tube. A hammer bit 9 is fixed to the lower end portion of the air hammer device 8 inserted into the casing 7. The air hammer device 8 has a weight 8w, and as described above, receives air supply and vibrates to apply impact to the hammer to perform excavation.

  Further, as described above, the ring bit 10 is provided at the lower end portion of the casing 7, and excavation is performed using the teeth of the ring bit 10 together with the hammer bit 9 of the air hammer device 8. The outer diameter step portion of the hammer bit 9 is in contact with the inner diameter step portion of the ring bit 10, and the ring bit 10 follows the operation of the hammer bit 9. The ring bit 10 has an outer circumferential uneven surface formed on the outer circumferential portion on the upper side for each predetermined angle. On the inner peripheral portion on the lower end side of the support member 11 that is a tubular member, an inner peripheral uneven surface that engages with the outer peripheral uneven surface of the ring bit 10 is formed. With the configuration in which the outer circumferential uneven surface of the ring bit 10 and the inner circumferential uneven surface of the support member 11 are engaged, the ring bit 10 is movable in the vertical direction with respect to the support member 11 and integrated with the support member 11. The structure is rotatable. In other words, as shown in FIG. 4, the shaft portion of the ring bit 10 and the hole portion of the support member 11 are coupled in a concavo-convex state, so-called spline coupling. That is, between the ring bit 10 and the support member 11, a rotational force is transmitted and relative movement in the vertical direction is possible.

  On the other hand, the support member 11 is provided with a pin 12 as shown in FIGS. 3 and 4 and is engaged with a long groove formed in the convex portion of the shaft portion of the ring bit 10. The ring bit 10 is attached so as to restrict the vertical movement relative to the member 11 and not to be detached from the support member 11. The ring bit 10 is attached to the casing 7 with the support member 11 interposed.

  In this manner, the ring bit 10 is configured to rotate integrally with the support member 11 in the rotational direction, although it can move in the vertical direction within a predetermined range. The support member 11 is screwed to the casing 7. An O-ring 13 is disposed on the inner peripheral surface on the upper side of the support member 11, and the space between the support member 11 and the air hammer device 8 is sealed by the O-ring 13.

  The ring bit 10 is configured as described above, and the ring bit 10 is arranged at the lower end of the casing 7, so that the casing 7 rotates to have the excavation ability on the casing 7 side. Increase your ability. Therefore, even if the excavation hole X becomes large, the excavation hole X can be compulsorily excavated by having an excavation function on the casing 7 side. For this reason, excavation of the excavation hole X for embedding the underground heat exchange pipe U corresponding to the performance of the underground heat pump system Y is possible with a simple configuration.

  By providing a sealing mechanism called the O-ring 13, the supplied high-pressure air for driving the air hammer does not leak to the outside even if the casing 7 and the air hammer device 8 move relative to each other. Even when the high-pressure air supply is stopped, foreign matter such as muddy water generated by excavation can be prevented from entering the casing 7. An upper portion of the air hammer device 8 serves as an engaging portion 14, and an overshot head 15 for pulling up, which will be described later, is engaged (see FIG. 11).

  A coupling portion 16 for coupling the casing 7 and the air hammer device 8 is disposed below the casing 7 and the air hammer device 8. The details are shown in FIGS. A part of the casing 7 protrudes inward as an inner diameter portion which is an inner hole of the casing 7 as a first coupling portion 7a. The first coupling portion 7a is a rod having a convex portion formed on the inner wall, which is the peripheral surface of the inner hole of the casing 7, and the upper portion is a rod upper convex portion 7b, and a rod having a concave portion partially formed in the lower portion thereof. A lower convex portion 7c is formed. The first coupling portion 7a is provided at four locations at equal angular intervals on the inner periphery of the casing 7.

  On the other hand, the outer peripheral surface of the air hammer device 8 is provided with a second coupling portion 8a corresponding to the first coupling portion 7a. The second coupling portion 8 a has hammer-side convex portions 8 b formed at four equal angular intervals on the outer periphery, and each corresponds to the first coupling portion 7 a of the casing 7. At the time of coupling, the casing 7 is rotated in one direction as indicated by an arrow shown in FIG. 5 (a) to couple the first coupling portion 7a and the second coupling portion 8a.

  That is, as shown in FIG. 5A, the hammer side convex portion 8b of the second coupling portion 8a is fitted into the concave portion of the rod lower convex portion 7c of the first coupling portion 7a, and the side wall of the hammer side convex portion 8b is the rod. It abuts against the concave portion of the lower convex portion 7c. At this time, the upper portion of the hammer side convex portion 8b is restricted by the rod upper convex portion 7b of the first coupling portion 7a, and the lower portion of the hammer side convex portion 8b is in contact with the end portion of the support member 11 and restricted. Therefore, the relative vertical movement and rotational movement are restricted.

  In this state, while the rotational operation is given in one direction (the arrow direction shown in FIG. 5 (a)), the casing 7 and the air hammer device 8 have the first coupling portion 7a and the second coupling portion 8a. Combined and integrated. With this configuration, the casing 7 and the air hammer device 8 can rotate integrally and be excavated. Next, when canceling this state, the casing 7 is reversely rotated in the other direction (the arrow direction shown in FIG. 5B) to obtain the state shown in FIG.

  In this state, the hammer-side convex portion 8b of the second coupling portion 8a is separated from the concave portion of the casing lower convex portion 7c of the first coupling portion 7a, and at the same time, the upper portion of the hammer-side convex portion 8b is also moved to the first coupling portion 7a. Away from the casing upper projection 7b. Thereby, the coupling | bonding of the 1st coupling | bond part 7a and the 2nd coupling | bond part 8a is cancelled | released, and the relative movement to the up-down direction is possible for the air hammer apparatus 8 between the casings 7. FIG. The excavation apparatus centering on the casing 7 and the air hammer apparatus 8 is configured as described above. Next, the excavation method will be described with reference to FIGS.

[Drilling method]
The state shown in FIG. 7 shows a process immediately before the air hammer device 8 is inserted into the casing 7 on the ground by the excavating machine 1. The right side of FIG. 7 is an enlarged view of the air hammer device 8 and the like. The air hammer device 8 is placed on the ground with its own weight and weight 8w, and a support member 11 and a ring bit 10 are provided on the lower side of the air hammer device 8. The upper end of the support member 11 is in contact with the lower end of the hammer protrusion 8b of the air hammer device 8, and the hammer bit 9 of the air hammer device 8 and the tooth bit of the ring bit 10 are positioned at the ring position of the hammer bit 9. The bit 10 is in contact with the ground when in contact.

  The casing 7 placed on the ground is gripped by the gripping portion of the motor (rotary drive means) 5. The feed hydraulic motor of the raising / lowering drive means is driven, and the guide 4 provided with the motor 5 is raised along the guide of the leader 2. The excavating machine 1 is moved so that the casing 7 is positioned above the air hammer device 8 placed on the ground. The feed hydraulic motor is driven to cover the air hammer device 8 so that the casing 7 is gradually lowered from above along the guide of the leader 2 via the guide 4. Subsequently, when the end portion of the casing 7 reaches the support member 11, the casing 7 is rotated by the motor 5, and the female screw at the lower end portion of the casing 7 is screwed into the male screw of the support member 11. At this time, the support member 11 is fixed so as not to rotate using a chain tongue or the like, and is screwed so that the casing 7 and the support member 11 are not loosened.

  Further, by the rotation of the casing 7, the first coupling portion 7 a of the casing 7 and the second coupling portion 8 a of the air hammer device 8 are coupled. After the screw is tightened, the rotation operation is stopped when the ring bit 10 also rotates together. When the screwing of the casing 7 to the support member 11 is completed, the state shown in FIG. 8 is obtained. Further, the relationship between the casing 7 and the air hammer device 8 at this time is as shown in FIG. 5A, and the first coupling portion 7a and the second coupling portion 8a are coupled. The air supply to the air hammer device 8 is supplied by the compressed air supply device as described above, supplied into the casing 7 as shown in FIG. 3, and supplied to the air hammer device 8 through the supply hole.

  Although not shown, the air is supplied from the compressed air supply device installed in the vicinity of the excavator into the casing 7 without leaking through the hose or the like. Subsequently, the motor 5 is rotated to rotate the ring bit 10 at the lower end of the casing 7, and at the same time, air is supplied to the air hammer device 8 to strike the hammer bit 9 at the lower end of the air hammer device 8. By this excavation operation, the ring bit 10 at the lower end of the casing 7 and the hammer bit 9 at the lower end of the air hammer device 8 are integrated to start excavation. The excavated earth and sand is driven to the outside of the casing 7 by the air discharged from the air hammer device 8, and is discharged from the excavation hole and a part thereof comes out to the ground.

  When the excavation depth is insufficient, the drawing is omitted, but the gripping of the casing 7 by the gripping portion of the motor 5 is released, the feed hydraulic motor is driven, and the motor 5 moves along the guide of the leader 2. The provided guide stand 4 is moved to the upper part of the leader 2 and is screwed onto the upper part of the casing 7 in which the additional casing 7 is embedded. The feed hydraulic motor is driven, and the guide base 4 provided with the motor 5 is lowered along the guidance of the leader 2 to a position where the grip portion of the motor 5 can grip the casing 7. The additional casing 7 is gripped by the gripping portion of the motor 5 and excavated to a predetermined depth in the same process as described above, as shown in FIG. When the excavation is completed, the motor 5 is rotated in the reverse direction to release the coupling between the first coupling portion 7a and the second coupling portion 8a as shown in FIG.

  After excavation to a predetermined depth, the gripping of the casing 7 by the gripping portion of the motor 5 is released. As shown in FIG. 10, the feed hydraulic motor is driven, and the guide 4 provided with the motor 5 is retracted to the top of the leader 2 along the guidance of the leader 2. After the overshot head 15 is lifted by the wire 17, as shown in FIG. 11, the overshot head 15 is hung in the casing 7 from the top of the leader 2. The overshot head 15 is a chucking device for the air hammer device 8.

  As shown in FIG. 3, the upper portion of the air hammer device 8 constitutes an engaging portion 14 and has a conical umbrella portion 14a and a constricted portion 14b in a lower step shape. The overshot head 15 is a pinch-shaped gripping member. When the overshot head 15 is suspended in the casing 7 and abuts against the engaging portion 14 of the air hammer device 8, the pinching portion 15a opens while being guided by the umbrella portion 14a, and the constriction When it reaches the portion 14b, the pinching portion 15a is closed by fitting, and the engaging portion 14 is gripped.

  After gripping, it keeps pinching with its own weight, so it will not come off. FIG. 11 shows a state in which the overshot head 15 grips the air hammer device 8. When the overshot head 15 is lifted in this state, the air hammer device 8 is separated from the casing 7 and is lifted up to the ground alone as shown in FIG. In this state, only the casing 7 is buried in the ground.

  Since the casing 7 is in the ground, the inner wall surface of the excavation hole X is not likely to be blocked by collapse even in a soft ground. The underground heat exchange pipe U is inserted into the casing 7. Grout (grouting material) Gr is injected and filled between the inner periphery of the casing 7 and the underground heat exchange pipe U. An underground heat exchange pipe U is embedded in the grout Gr filled in the casing 7. At this time, when there is groundwater inside the casing 7 (hollow part), the grout Gr fills a gap between the inner peripheral part of the casing 7 and the underground heat exchange pipe U while removing the groundwater accumulated in the basement. . The feed hydraulic motor is driven, and the guide base 4 provided with the motor 5 is lowered along the guidance of the leader 2 to a position where the grip portion of the motor 5 can grip the casing 7. The casing 7 is gripped by the gripping portion of the motor 5. The feed hydraulic motor is driven, the moving table 4 provided with the motor 5 is raised along the guide of the leader 2, and the casing 7 is pulled out from the ground and collected. In other words, the casing 7 is pulled up to the ground. Grout Gr fills the space in the ground from which the casing 7 is pulled out.

  In this way, the underground heat exchange pipe U is finally embedded in the grout Gr filled in the excavation hole X as shown in FIG. As described above, in the present embodiment, the ring bit 10 is provided at the end of the casing 7 for excavation, so that the excavation capability can be increased in combination with excavation by the hammer bit 9 of the air hammer device 8.

  That is, the ground just under the casing 7 can be excavated with the ring bit 10. This makes it possible to cope with changes in soil quality such as hard soil layers even in soft ground. In the present embodiment, the ring bit 10 is provided in the casing 7, and the entire hole is forcibly excavated together with the hammer bit 9. As a result, it is possible to cope with the ground where any general house is constructed without being influenced by changes in soil quality, and the underground heat exchange pipe (ground) can be smoothly and without damaging the casing 7 during excavation. The excavation hole X for installing the intermediate heat exchanger (U) can be excavated. Furthermore, the coupling configuration of the casing 7 and the air hammer device 8 is configured to be detachable in a simple manner. As a result, the excavation apparatus for installing the underground heat exchanger according to the present embodiment is not a complicated apparatus, and a low-cost apparatus and highly efficient excavation can be realized.

[Other embodiments]
15 to 17 are diagrams showing another embodiment of the excavator. In this other form, the bit relationship is the same as that described above, and only the coupling part is changed as shown in FIGS. Note that the packer unit and the like in FIG. 15 are illustrated with the right half in the coupled release state and the left half in the coupled state. As shown in the figure, a concave groove 31 is provided in a part of the inner diameter portion of the casing 30 and is coupled to the concave groove 31 by a packer portion 32 that expands and contracts freely. Four stoppers 33 are provided in the circumferential direction between the concave groove 31 and the packer portion 32. This stopper 33 is configured to be pressed against the packer portion 32.

  A plug 40 is removed from the packer portion 32, and water pressure is applied from an external water pressure supply device (water pressure pump) through a hose. A water passage 35 for supplying pressure water to the inside of the air hammer device 34. Is provided. The water pressure is structured such that the checker 41 keeps the water pressure in the packer even if the hose from the water pressure supply device (water pressure pump) is removed. The packer portion 32 is formed of a rubber body and is expanded by water pressure. The stopper 33 is provided with an O-ring 36. When the casing 30 and the air hammer device 34 are coupled, as shown in FIG. 17 (a), the packer portion 32 is expanded by supplying pressurized water, and the stopper 33 is fitted in the concave groove 31, and the casing 30 and The relative movement in the vertical direction with the air hammer device 34 is restricted.

  When releasing the connection, as shown in FIG. 17B, the water pressure release valve 42 is pushed by the overshot head, whereby the pressure water in the packer portion 32 is reduced, and the stopper 33 is released from the groove 31. At the time of detachment, the stopper 33 is retracted to the packer unit 32 side by the restoring force of the O-ring 36 and the packer unit 32 in addition to stopping the water pressure of the packer unit 32. In this way, the casing 30 and the air hammer device 34 can be moved relative to each other in the vertical direction.

  Further, the casing 30 and the air hammer device 34 can be relatively moved in the vertical direction by the spline coupling structure 37, but the rotational direction is regulated. In the case of this other form, it is not necessary to perform mutual rotational alignment between the casing 30 and the air hammer device 34 at the time of coupling.

  As mentioned above, although embodiment of this invention was described, it cannot be overemphasized that this invention is not limited to this form, and can change within the range which does not deviate from the objective of this invention and the meaning. The present invention is for excavation hole formation for installing the underground heat exchanger of the geothermal heat pump system, but can also be applied to the one in which gravel is injected into the excavation hole to form a pile. In general, there are many examples of drilling hole formation in the field of civil engineering construction, but the object of the excavation method integrated with the casing having the bit and the air hammer device in the present invention is not limited. Needless to say, it can handle anything.

DESCRIPTION OF SYMBOLS 1 ... Excavation machine 2 ... Leader 5 ... Motor 7 ... Casing 7a ... 1st connection part 8 ... Air hammer apparatus 8a ... 2nd connection part 9 ... Hammer bit 10 ... Ring bit 11 ... Support member 14 ... Engagement part 15 ... Over Shot head 16 ... Joint Gr ... Grout U ... Underground heat exchange pipe (Ground heat exchanger)
X ... Ground heat exchanger installation hole Y ... Ground heat heat pump system

Claims (10)

A hollow casing (7) that is rotationally driven by the rotational drive means (5) has a hammer bit (9) at the lower end, and a weight for suppressing the hammer bounce at the upper part to place the hammer downward. In the excavation device that excavates the underground heat exchanger installation hole by incorporating the air hammer device (8) to be generated,
A ring bit (10) disposed at the lower end of the casing (7) on the ground side and installed in accordance with the installation site of the hammer bit (9);
In order to excavate the underground heat exchanger installation hole, which is provided across the casing (7) and the air hammer device (8) and is integrated with the casing (7) and the air hammer device (8). A drilling device for forming an underground heat exchanger installation hole, comprising a coupling portion (16) coupled to the ground heat exchanger. In the excavation device for forming the underground heat exchanger installation hole according to claim 1,
The coupling part (16)
A first coupling part (7a) provided on the inner diameter part of the casing (7) and a second coupling provided on the outer diameter part of the air hammer device (8) and freely abutted against the first coupling part (7a) Part (8a),
Both the casing (7) and the air hammer device (8) can rotate integrally, and when the two are abutted by relative movement in the rotational direction, the relative movement in the vertical direction is restricted, and when the abutment is released, the vertical direction An excavation apparatus for forming a hole for installing an underground heat exchanger, characterized in that the relative movement of the underground heat exchanger is possible. In the excavation device for forming the underground heat exchanger installation hole according to claim 1,
The coupling part (16)
A first coupling portion (31) provided in an inner diameter portion of the casing (30);
A second coupling portion (33, 32) provided on an outer diameter portion of the air hammer device (34) and protruding and coupled to the first coupling portion (31);
When the casing (30) and the air hammer device (34) can rotate together and the second coupling part (33, 32) protrudes, the relative movement in the vertical direction is restricted, and the second coupling part (33 , 32) is configured to enable relative movement in the vertical direction when retracted, a drilling device for forming an underground heat exchanger installation hole. In the selected one of the excavating apparatus for forming the underground heat exchanger installation hole according to claim 1,
The casing (7) and the air hammer device (8) are excavated by an elevating drive means and a rotary drive means (5) installed in a leader (2) of an excavating machine (1). Drilling rig for heat exchanger installation hole formation. In one selected excavation apparatus for forming the underground heat exchanger installation hole according to claim 1,
The said ring bit (10) is the structure attached to the said casing (7) via the supporting member (11). The excavation apparatus for underground heat exchanger installation hole formation characterized by the above-mentioned. In one selected excavation device for forming a geothermal heat exchanger installation hole according to claim 1,
The ring bit (10) is configured to be movable along the excavation direction of the casing (7) with respect to the support member (11). Excavation for forming an underground heat exchanger installation hole apparatus. In one selected excavation device for forming a ground heat exchanger installation hole according to claim 1,
The air hammer device (8) includes the excavating machine (1) via an engaging member (15) that is detachable when the first coupling portion (7a) and the second coupling portion (8a) are separated. An excavation apparatus for forming an underground heat exchanger installation hole, wherein the excavation apparatus is configured to be lifted away from the casing (7) by driving of the lifting drive means. In one selected excavation device for forming a ground heat exchanger installation hole according to claim 1,
The rotary drive means (5) is provided on a guide stand (4) movable with respect to the leader (2) of the excavating machine (1). Drilling rig for hole formation. In one selected excavation device for forming a ground heat exchanger installation hole according to claim 1,
The casing (7) is configured to be pulled up by the lifting / lowering driving means of the excavating machine (1) through the gripping part on the rotation driving means (5) side. Drilling rig for forming. In the hollow casing (7) that can be rotated by the rotation drive means (5), a hammer bit (9) is provided at the end, and a weight is placed on the upper part to prevent the hammer from jumping, and a downward impact is generated. In an excavation method for excavating a ground heat exchanger installation hole by installing an air hammer device (8)
Inserting an air hammer device (8) having a hammer bit (9) at its end into the casing (7), and fixing a ring bit (10) to the casing (7) end;
Coupling the first coupling part (7a) provided in the casing (7) and the second coupling part (8a) provided in the air hammer device (8) to integrate them;
Hitting with the air hammer device (8) while rotating the casing (7) in one direction, and excavating to a predetermined depth in the ground with the ring bit and the hammer bit;
After excavating to a predetermined depth, releasing the coupling of the casing (7) and the air hammer device (8), and pulling the air hammer device (8) to the ground;
Inserting and burying an underground heat exchanger in the casing; and
The excavation method for forming a geothermal heat exchanger installation hole, comprising the step of lifting the casing (7) to the ground and installing the underground heat exchanger in an excavation hole.

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