JP7092300B2 - Underground propagation signal transmitter / receiver, underground work head, underground work machine and underground work system, and underground work management method - Google Patents

Description

The present invention relates to an underground propagation signal transmission / reception device suitable for monitoring underground work such as bottom-expanding excavation work, and a head portion for underground work to which a transmission device of the underground propagation signal transmission / reception device is attached, in particular. Is an underground work that collectively manages the underground work of an expansion excavation head for bottom expansion excavation, underground work machines such as a bottom expansion excavator equipped with the head, and multiple underground work machines such as multiple bottom expansion excavators. Regarding the system and the underground work management method using the underground work system.

As foundation work for a building, after excavating a pile hole until it reaches the support layer of the ground, the bottom is expanded and excavated (expanded), the foundation pile is built there, and concrete is placed at the bottom. It is known to increase the bearing capacity of the stake. In such bottom expansion excavation work, it is important to confirm whether the bottom of the pile hole is really expanded. Therefore, it is possible to confirm after the fact whether the shear pin attached to the expansion excavation head used for excavation is actually expanded by checking whether the shear pin is crushed after the bottom expansion excavation work (Patent Document 1), or with the expansion excavation head operated by hydraulic pressure. If so, it can be determined from the amount of oil supplied to the hydraulic cylinder whether or not the bottom has been expanded, or the mechanical vertical movement of the rod rod connected to the movable part of the expanded excavation head, or the displacement of the expanded excavation head. It has been practiced to grasp the state of the magnified excavation head on the ground through the converted electric signal.

However, when checking the condition of the expanded excavation head using a shear pin, it is not possible to determine whether or not the expanded excavation head has been expanded until the expanded excavation head is once pulled up from deep in the ground, and the bottom is expanded at that stage. When it is found that there was no such problem, the expansion excavation head must be returned to the ground and the excavation must be redone, and the condition of the expansion excavation head is determined based on the amount of oil in the hydraulic expansion excavation head. In some cases, the problem of not being able to make an accurate judgment if there is a leak somewhere in the hydraulic system, or the method of converting the state of the magnified excavation head into mechanical or electrical information and guiding it to the ground. As the excavation work progresses, rods and cables must be added, and there is a troublesome problem that cables and the like must be wrapped around the drive pipe that rotates and propels the expanded excavation head.

Therefore, in order to confirm whether or not the expanded excavation head in the ground has expanded, the present inventors wirelessly change the state of the expanded excavation head to the ground through the water filled in the pile hole. We have been working on the development of transmission technology (Patent Document 2). FIG. 7 shows a wireless blade expansion bit opening / closing detection device that detects the opening / closing operation of the blade expansion bit of the expansion excavation head that excavates such a bottom expansion pile hole. In FIG. 7, the bottom expansion excavator 100 is provided with an expansion excavation head 110 for excavating underground at the tip of a drive pipe 170. The expansion excavation head 110 has a tip bit 120 on the tip side and a blade expansion bit 130 extending rearward in the drilling direction of the tip bit 120, and when the pile hole A is first dug, the blade expansion bit 130 is used. As soon as the pile hole A reaches the support layer of the ground, the wing expansion bit 130 rotates around the pin 140 and the tip is closed. The bit 120 and the wing expansion bit 130 are configured to cooperate to excavate the bottom expansion portion D that is larger than the pile hole A (see the right side (B) of FIG. 7). When the wing expansion bit 130 rotates, the magnet 150 and the magnet type proximity switch 160 are in a positional relationship facing each other, and a radio wave is transmitted above the pile hole A from a transmission device (not shown), and this radio wave is watered on the ground side. By receiving the signal via the beam, it is possible to grasp on the ground that the expansion bit 130 has expanded.

Japanese Unexamined Patent Publication No. 2017-61787 Jikken Sho 62-7746 Gazette

However, at the actual excavation work site, not only one excavator is operating as described above, but multiple excavators (several dozens at most) are lined up in a large site, and each of them is lined up. Generally, excavation work is done in parallel. Through the efforts so far, it has been found that the radio waves transmitted from the transmitter attached to the magnifying excavation head unexpectedly propagate not only underwater but also through the ground over a long distance. Then, as expected, radio waves from multiple excavators will enter one receiving device, and it will be indistinguishable among the excavators, and which state of the excavator's expanded excavator will be in what state. It is possible that you will not know if it is in. Therefore, it is conceivable to distinguish the bottom-expanding excavators by frequency by making the frequencies of the radio waves transmitted by the transmitters attached to the expanding excavation heads of multiple bottom-expanding excavators different, but we will actually try it. It turned out that the noise of harmonics rides while the radio wave travels in the ground, the frequencies cannot be sufficiently distinguished even through the filter, and interference occurs between different frequencies, making them indistinguishable from each other. Moreover, in order to change the frequency for each excavator, it is necessary to prepare multiple transmitters for each frequency. There is a problem that the work of managing which expansion excavator the transmitter is assigned to is complicated. This is not realistic at excavation work sites where there are dozens of excavators.

Further, the conventional bottom-expanding excavator has the same configuration as that in the above-mentioned conventional example, when the magnet 150 and the magnet type proximity switch 160 face each other, radio waves continue to be transmitted, and the power consumption is remarkable. .. Therefore, the transmitter is equipped with a plurality of lead-acid batteries in order to secure the electric power for one work, and the size of the transmitter has to be increased accordingly. If such a large transmitter is placed between screws that feed mud for waste soil, it becomes a transport resistance, so the size of the transmitter is relatively small compared to the diameter of the pile hole to be excavated. It was necessary to suppress the influence by doing so. As a result, the bottom-expanding excavator to which the transmission device can be attached is also limited to large-sized excavators having a pile diameter of φ1200 mm, such as the earth drill method and the reverse method used for cast-in-place piles. However, the excavation depth required today in landfills in the bay area may exceed 100 m, making it difficult for transmitted radio waves to reach, and the types of pile diameters are increasing, and even those with a small pile diameter of φ500 mm are required. The conventional transmitter has a problem that it cannot be structurally attached to a bottom-expanding excavator for such a small-diameter pile hole.

Up to this point, the problem of the bottom-expanding excavator has been mainly dealt with, but the problem mentioned earlier is not limited to the bottom-expanding excavator, and it is necessary to grasp the state of the head part that generally performs underground work. It can be said that this is a common problem for machines.

Therefore, in view of the above problems, the present invention makes a distinction between the underground work machines even if the transmission device is attached to the head portion of a plurality of underground work machines, particularly the enlarged excavation head of the bottom expansion excavator. The purpose is to reduce the size of the transmitter so that the state of the head can be grasped and the size of the head to which the transmitter can be attached can be freely selected.

The present invention is an underground propagation signal transmission / reception device (4) used for an underground work machine (2) having a head portion (30) for performing underground work at the tip of a work portion (22), and is a head portion (30). ), And when the head unit (30) is in a predetermined state, a transmitter (6) that transmits a radio wave of a predetermined frequency to the ground and receives the radio wave to correspond to the predetermined state of the head unit (30). In the underground propagation signal transmission / reception device (4) including the reception device (8) for generating the output signal, the transmission device (6) transmits a signal based on the unique identification information of the transmission device (6). The receiving device (8) identifies the transmitting device (6) having the identification information based on the identification information of the transmitting device (6) obtained from the received signal. An output signal is output together with a signal representing the specified transmission device (6).

As a result, when the head portion for performing underground work reaches a certain predetermined state, radio waves are transmitted from the transmission device attached to the head portion at a predetermined frequency (several Hz to several tens of kHz) propagating in the ground. .. If this radio wave is received, for example, by an antenna inserted in the ground and output as an output signal corresponding to the above-mentioned predetermined state, it can be confirmed from the output signal that the head portion during underground work is in the above-mentioned predetermined state. .. This output signal may be a signal such as sound or light that can be perceived by humans, or may be a signal that can be input to a PC or other electronic device. At this time, for example, if the radio wave propagating in the ground is used as a carrier wave and the identification information peculiar to the transmitting device is signalized, particularly encoded into a digital signal and then modulated and placed on the carrier wave, the received radio wave is demoted and obtained. By decoding from the signal, particularly a digital signal (hereinafter, may be simply referred to as a “received signal”) and extracting the identification information of the transmitting device, the transmitting device that transmitted the radio wave can be specified. Then, by outputting a signal representing the specified transmission device together with the output signal, the identification signal can be used for identification and management of the transmission device when the output signal is used. As described above, according to the present invention, it is possible to distinguish the transmitting device without changing the frequency of the radio wave for each transmitting device in order to distinguish the transmitting device, so that it is extremely easy to manage when there are a plurality of transmitting devices. become.

Further, in the present invention, the transmitting device (6) transmits radio waves for a predetermined period when the head portion (30) is in a predetermined state, and then determines whether or not the head portion (30) is continuously in the predetermined state. Regardless, the transmission of radio waves is stopped.

As a result, even if the head unit continues to stay in a predetermined state, the transmitting device does not continue to transmit radio waves, and after transmitting radio waves for a predetermined period (for example, for several seconds), the transmission is stopped to waste power. Do not consume. This reduces the size of the battery and the overall size of the transmitter. As the size of the transmitter becomes smaller, the range of choices for the head of the underground work machine to which the transmitter is attached is expanded. In addition, when multiple transmitters are attached to the heads of multiple underground work machines, unlike the case where they continue to transmit radio waves, it is no longer necessary to receive radio waves from multiple transmitters at the same time. Can be correctly distinguished.

Further, the present invention is a head portion (30) provided at the tip of a working portion of the underground work machine (2) for performing underground work, and is a transmission device (4) of the above-mentioned underground propagation signal transmission / reception device (4). It is a head portion (30) to which 6) is attached.

With such a head unit, as described above, the head unit to which the transmitter is attached is identified based on the identification information of the transmitter, and the state of the head unit is monitored and managed for each head unit. Can be done.

Further, the head portion (30) is formed as an expansion excavation head (30) provided at the tip of a work portion of an underground work machine as a bottom expansion excavator (2), and the predetermined state of the head portion (30) is as described above. , The expansion bit of the expansion excavation head is open.

In this way, if the head portion is an expansion excavation head, when the expansion bit is in the open state, that state can be grasped from the signal received on the ground, and at that time, from the identification information of the transmission device. , The magnified excavation head to which the transmitter is attached can be identified, and the state of the magnified excavation head can be grasped, monitored and managed while distinguishing a plurality of magnified excavation heads.

The present invention is an underground work machine (2) having the head portion (30) at the tip of the work portion.

Such an underground work machine can perform the same monitoring and management as the head portion attached to the underground work machine. When the transmission device is configured to transmit the radio wave for a predetermined period and then stop the transmission of the radio wave when the head portion is in a predetermined state, the size of the transmission device becomes smaller and the head portion to which the transmission device is attached becomes smaller. As the range of selection expands, the range of selection of the underground work machine also expands. For example, when the underground work machine is a bottom expansion excavator, one for φ500 mm having a small pile diameter can also be used.

The present invention has a control unit (24) for monitoring the progress of underground work in such an underground work machine (2), and the control unit (24) is the above-mentioned underground propagation signal transmission / reception device ( The output signal is received from the receiving device (8) of 4) together with the signal representing the transmitting device (6), and the progress of the underground work and the predetermined state of the head portion (30) are recorded in association with each other.

In the underground work machine of the present invention, the progress of the underground work is monitored and controlled by the control unit. The control unit uses the output signal sent from the receiving device together with the signal representing the transmitting device to extract the output signal related to the head unit mounted on its own underground work machine, and any progress of the underground work. It is possible to record the state of the head portion in association with each other.

The present invention further includes at least one receiving device (8) of the above-mentioned underground propagation signal transmission / reception device (4), a plurality of the above-mentioned underground work machines (2), and a management device (9). It is an underground work system. Then, this management device (9) acquires a signal representing the transmission device (6) attached to each of the head portions (30) of the plurality of underground work machines (2) from the reception device (8). The underground work machine (2) is identified based on the signal, and the predetermined state of the head portion (30) of the underground work machine (2) is monitored for each identified underground work machine (2). Or record.

According to this underground work system, a plurality of simultaneous progresses while identifying a plurality of underground work machines by the identification information of the transmission device without changing the frequency of the radio wave for each transmission device or each underground work machine. Can manage underground work. That is, it is possible to monitor and record the state of each head portion of the plurality of underground work machines for each head portion using the identification information of the transmission device attached to the head portion.

Further, the present invention further attaches a transmission device to the head portion of an underground work machine having a head portion for performing underground work at the tip of the work portion, and when the head portion reaches a predetermined state, the information of the predetermined state is combined with the information of the predetermined state. The unique identification information of the transmission device is transmitted from the transmission device to the ground, the information of the predetermined state of the head portion and the identification information of the transmission device are received, and the identification of the transmission device received. The transmitter is identified based on the information, the head portion to which the identified transmitter is attached, and the underground work machine having the head portion are identified, and the identified head portion or the underground work is identified. The underground work is managed by monitoring, recording, or controlling at least one of the predetermined states of the head portion received for each machine.

According to this underground work management method, it is possible to manage a plurality of underground work progressing simultaneously while identifying a plurality of underground work machines by the identification information of the transmission device. That is, the state of each head of a plurality of underground work machines can be monitored, recorded or controlled for each head or underground work machine by using the identification information of the transmitter attached to the head. You can do at least one.

It is a figure which shows roughly the whole of the bottom expansion excavator and the transmission / reception device of this invention. It is a figure which shows the vicinity of the expansion excavation head of the expansion excavator of this invention. It is a figure which shows the state in which the expansion bit of the expansion excavation head of the expansion excavator of the present invention is closed and the state in which it is expanded, respectively. It is a partially enlarged view of the magnified excavation head of this invention, and is the figure which shows the positional relationship between the arrangement of the magnet type proximity switch for detecting the state of the blade expansion bit, and the magnet attached to the blade expansion bit. It is a block diagram of the transmission / reception device of this invention. It is a schematic diagram of the bottom expansion excavation system of this invention. It is a figure which shows the conventional magnifying excavation head and the transmission device attached to it.

FIG. 1 schematically shows the entire bottom expansion excavator 2 (underground work machine) and transmission / reception device 4 (underground propagation signal transmission / reception device).

The bottom expansion excavator 2 has an expansion excavation head 30 (head portion) for excavating a pile hole A deep in the ground (head portion), and an expansion excavation head 30 is attached to the tip and a rotational force is applied to the expansion excavation head 30. The drive pipe 22 (working part), which transmits thrust and is extended at any time via the pile joint part 23 as the excavation depth becomes deeper, and the drive pipe 22 are suspended and supported together with the drive part. A construction machine vehicle 21 that can be moved to a required work site, and a control unit 24 that is mounted on the construction machine vehicle 21 to monitor and record the progress of excavation work by the bottom expansion excavator 2 and control the entire excavation work. And have.

As shown in FIGS. 2 and 3, the enlarged excavation head 30 mounted on the tip of the drive pipe 22 has a head main body 31 having a tip bit 33 for excavating a pile hole A at the tip and a center thereof. A closed state (see FIG. 3A) in which the tip is supported by a pin 37 and the tip is brought toward the head body 31 side, and an enlarged state in which the tip is rotated to the maximum in the direction away from each other. It has a pair of wing expansion bits 34, 34 that can be rotated to and from (see FIG. 3B).

Then, as shown in FIGS. 3 to 4, the arm 35 extends in the direction opposite to the tip end side of the blade expansion bit 34 with the pin 37 of the blade expansion bit 34 interposed therebetween. In order to define the movable range, the stoppers 32 and 32 with which the arm 35 abuts in the closed state and the expanded state (predetermined state of the head portion) (hereinafter, may be referred to as “fully open state”) of the blade expansion bit 34, respectively. Is erected at the corresponding portion of the head body 31.

Further, as can be seen from FIG. 4, the magnet 36 is attached to the surface of the arm 35 on the head body 31 side, while the magnet 36 is attached to each of the three locations along the trajectory through which the magnet 36 passes as the wing expansion bit 34 rotates. Magnet type proximity switches 61, 62, 63 are provided, and when the expansion bit 34 starts to expand from the closed state, the magnet 36 first comes to the position of the magnet type proximity switch 61 and is in a slightly open state (predetermined head portion). The wing expansion bit 34 continues to expand, the magnet 36 comes to the position of the magnet type proximity switch 62, and the wing expansion bit 34 becomes a fully open state (predetermined state of the head portion), and the wing expansion bit 34 further expands. When the fully expanded state (enlarged state) (predetermined state of the head portion) is reached (the arm 35 is shown by a two-point chain line in FIG. 4), the magnet 36 is a magnet type proximity switch 63. It is designed to reach the position of.

Further, as shown in FIG. 2, a transmitter 64 accessible via an opening / closing portion (not shown) is incorporated in the drive pipe 22 to which the enlarged excavation head 30 is mounted. The transmitter 64 is connected to the wiring drawn into the drive pipe after passing through the protective tube starting from the magnetic proximity switches 61, 62, 63. The transmitter 64 also shown in FIG. 5 has a 24 V to preferably 12 V battery power supply using a lithium ion battery, a relay circuit, a carrier wave generator, individual identification information of the transmitter, and the like in a protective waterproof casing. To transmit the identification information of a transmitting device such as an information signal converter 65 that encodes a digital signal into a digital signal, a modulator 66 that performs digital modulation to mount a digital signal on a carrier wave, and an amplifier, for example, on a radio wave as a digital signal. It has the necessary circuits. Here, as a method of modulating the encoded identification signal and placing it on the radio wave, any digital modulation method such as amplitude modulation, phase modulation, amplitude phase modulation, and QAM modulation can be used. Here, the configuration is such that the identification information is transmitted as a digital signal, but it goes without saying that the mode does not matter as long as the identification information can be transmitted. Further, one wire drawn from the transmitter 64 is connected to the conductor portion of the transmitting antenna 67 fixed at the peripheral surface position near the enlarged excavation head 30 of the drive pipe 22, while the other wire is the drive pipe. It is grounded to 22. Here, the transmission antenna 67 is fixed at the peripheral surface position of the drive pipe 22 near the expanded excavation head 30 so that radio waves can be transmitted even if the expanded excavation head 30 does not protrude so much from the PC pipe in the case of the Nakabori method or the like. This is so that it can be sent.

The transmitting antenna 67 has a donut shape formed so as to go around the peripheral surface of the drive pipe 22, and inside the donut-shaped insulating sheet made of MC nylon, which is provided around the drive pipe 22 and is responsible for insulation from the drive pipe 22. The 68 is further configured with an annular belt-type conductor portion 69 formed so that a copper belt having a thickness of several mm is wound around the outside thereof. The conductor portion can be arranged as a rectangle on a part of the peripheral surface, but by making it an annular belt type, radio waves are transmitted isotropically from the transmitting antenna 67, and the transmitting antenna 67 rotates together with the drive pipe 22. Even so, the strength of the radio wave received at the fixed position does not change.

As described above, the transmitter 6 of the present invention is configured by the magnetic proximity switches 61, 62, 63, the transmitter 64, the transmitter antenna 67, and the like.

As schematically shown in FIG. 1, the radio wave transmitted from the transmitting device 6 is received by the receiving device 8 via the ground. The receiving device 8 is required to demodulate the receiving antenna 86 whose tip is inserted into the ground at a predetermined location within a range of, for example, 5 to 50 m centered on the bottom expansion excavator 2, and the radio wave received by the receiving antenna 86. It has a receiver 81 for taking out a signal, and an output unit 84 for outputting the taken out signal to the outside.

FIG. 5 shows the configuration of the transmission / reception device 4 (underground propagation signal transmission / reception device) of the present invention including the transmission device 6 and the reception device 8 described above by a block diagram.

First, in the transmission device 6 of the transmission / reception device 4, when the magnet 36 arrives at a position facing the magnet type proximity switches 61, 62, 63, the magnet type proximity switches 61, 62 via a relay (not shown) on the transmitter 64 side. , 63, the transmission circuit corresponding to each is turned on, the unique identification information possessed by the transmission device 6 is encoded by the information signal converter 65 into a digital signal, and this is sent to the modulator 66 for digital modulation. As a result, the transmission antenna 67 is configured to transmit the radio wave carrying the identification information of the transmission device 6 for a predetermined period of several seconds, for example, only for 2 seconds. Here, different frequencies are selected for the radio waves transmitted when the magnetic proximity switches 61, 62, 63 are switched on, and which switch of the magnetic proximity switches 61, 62, 63 is selected due to the difference in frequency. It is possible to determine whether it has entered. In this embodiment, 3 kHz is selected for the magnet type proximity switch 61, 3.2 kHz for the magnet type proximity switch 62, and 3.5 kHz for the magnet type proximity switch 63, but these frequencies are in the ground. Can be arbitrarily selected in the range of several Hz to several tens of kHz, preferably several kHz capable of propagating.

Next, the receiving device 8 of the transmitting / receiving device 4 includes a receiving antenna 86 and a receiver 81 which is connected to the receiving antenna 86 and is grounded to the ground, the construction machine vehicle 2 and other grounding points, and is a transmitting device. When the radio wave transmitted from 6 is received by the receiving antenna 86, the digital signal is demolished by the demodulator 82 for each frequency assigned to the magnetic proximity switches 61, 62, 63 via a filter (not shown) in the receiver 81. Then, the information signal converter 83 decodes the identification information that identifies the transmitting device 6 from the digital signal. In this way, according to the switch state of the magnetic proximity switches 61, 62, 63, the output signal (the signal indicating the state of the enlarged excavation head 30 such as the slightly opened state, the medium open state, and the fully open state) is generated together with the identification information of the transmission device 6. It is configured to be output from the output unit 84. Here, in this embodiment, the output signal is addressed to the control unit 24 of the bottom-expanding excavator 2 to which the identified transmission device 6 is attached and the management device 9 described later that manages the full-bottom excavator. It is configured to be transmitted wirelessly from. Further, in the present embodiment, the receiving device 8 outputs information corresponding to each state of the enlarged excavation head 30 to the display unit 85 so that the operator can recognize it through sight and hearing. At this time, the display unit 85 has a lamp or buzzer that transmits information to the operator through light, sound, or the like, or a display or other display that displays information (for example, an excavator number) of the identified transmission device 6 in characters or images. A display means is provided. In particular, the transmitting device 6 is configured to be charged within 24 hours, but when the battery of the transmitting device 6 is exhausted and the voltage drops, a blinking display is displayed on the receiving device 8 side. Can encourage charging.

When the control unit 24 of the bottom expansion excavator 2 receives information from the receiving device 8 about the state of its own expansion excavation head 30 based on the identification information, the progress status of the excavation work monitored and controlled by the control unit 24 (for example). The excavation depth, the number of rotations of the head, the torque, etc.) and the state of the enlarged excavation head 30 are recorded and managed in combination. Then, the information is used to control the subsequent work.

Next, FIG. 6 shows an excavation work system S (underground work system) having a plurality of bottom-expanding excavators 2, 2 ..., a transmission / reception device 4, and a management device 9 placed in the management building H. Is shown. The management device 9 grasps and manages the progress of the work of the plurality of bottom-expanding excavators 2, 2 ... Based on the information sent from the control unit 24 of each bottom-expanding excavator 2. Then, a control command is sent to each of the bottom expansion excavators 2, 2 ... As necessary. At this time, the management device 9 identifies the bottom-expanding excavator 2 to which the transmitting device 6 is attached based on the signal representing the identified transmitting device 6 transmitted from the receiving device 8, and the identified bottom-expanding excavator. For each machine 2, the state of the enlarged excavation head 30 is recorded while monitoring the progress of the work of the bottom-expanding excavator 2. The information is then used to manage and control subsequent work.

Next, the excavation work management method (underground work management method) using the excavation work system S (underground work system) shown in FIG. 6 will be described with reference to FIGS. 1 to 6. Details of the excavation work system S (for example, details of the enlarged excavation head 30) not shown in FIG. 6 will be described with reference to the corresponding drawings of FIGS. 1 to 5.

As shown in FIG. 6, the excavation work management method of the present invention is parallel in parallel on the site of a construction site, for example, one hundred to several hundred meters square, in order to carry out the foundation work of the expansion pile of the planned building. This is a method of managing several to dozens of bottom-expanding excavators 2 and 2 for excavation work (only two bottom-expanding excavators are shown in FIG. 6 for simplification). Each of the bottom expansion excavators 2 is as shown in FIG. 1 in addition to FIG. 6, and after being moved to the planned excavation position by the construction machine vehicle 21, the expansion excavation head 30 (head) for a pile diameter of φ500 mm is at the tip. The drive pipe 22 (working part) to which the part) is mounted is suspended and held at the excavation position, and the drive pipe 22 is rotated by the drive source together with the enlarged excavation head 30 to propel the ground. At this time, the drive pipe 22 is appropriately extended via the pile joint portion 23 according to the excavation depth.

As shown in detail in FIGS. 2 and 3, the enlarged excavation head 30 is in a state where the blade expansion bit 34 is closed (for example, in the case of a pile diameter of φ500 mm, for example, an outer diameter) while rotating (forward rotation) in the forward direction. Φ430 mm) and excavate the pile hole A. At this time, the casing pipe P surrounding the expansion excavation head 30 is simultaneously inserted into the pile hole so that the tip bit 33 protrudes from the casing pipe P, while the wing expansion bit 34 is housed in the casing pipe P. (See Fig. 3 (A).) Excavate. Two holes for water and air penetrate in the drive pipe 22 and the pile joint portion 23, and these are ejected from the tip bit 33 at the time of excavation. Then, the earth and sand excavated by the tip bit 33 is discharged to the ground while being conveyed upward in the casing pipe P by a screw for waste soil (not shown) for easy viewing. It can be seen from the fact that the ground has reached the support layer where the excavation resistance is high, and that the drive noise and vibration of the excavator and other conditions and that the monitor is approaching the set depth are displayed. Excavation is advanced until the blade bit 34 is sufficiently pulled out from the casing pipe P, then the rotation direction is reversed, and the blade expansion bit 34 is expanded by utilizing the resistance of the earth pressure received from the ground (see FIG. 3B). .). Then, the expanded excavation head 30 reciprocates up and down two or three times with the blade expanding bit 34 opened (for example, in the case of a pile diameter of φ500 mm, for example, an outer diameter of φ650 mm) while rotating (reversing) in the opposite direction. While moving, for example, the bottom expansion portion D whose outer diameter is expanded 1.2 to 2 times is excavated over about 1 m. When the bottom expansion portion D is sufficiently excavated, the rotation direction is returned to the positive direction again, the expansion bit 34 is closed, and the expansion excavation head 30 is pulled up from the ground through the casing pipe P. At this time, concrete milk (bentonite or the like) is pressure-fed into the holes through which water has flowed to fill the inside of the casing pipe P in a columnar shape. In this way, pile driving is completed.

When the expansion excavation head 30 rotates in the normal direction, the expansion bit 34 is housed in the casing pipe and the arm 35 abuts on the stopper 32 so that the expansion bit 34 is initially closed as shown in FIG. 3A. However, when the expansion excavation head 30 is reversed after the expansion bit 34 is sufficiently pulled out from the casing pipe, the expansion bit 34 receives excavation resistance in the opposite direction and gradually begins to expand. Then, as shown in FIG. 3B, as the expansion bit 34 of the expansion excavation head 30 becomes a slightly open state, a medium open state, and a fully open state, the magnet 36 attached to the arm 35 is a magnet type in the slightly open state. It faces the proximity switch 61, the magnet type proximity switch 62 in the middle open state, and the magnet type proximity switch 63 in the fully open state. In each of the slightly open state, the medium open state, and the fully open state (predetermined state of the head portion) of the blade expansion bit 34, the magnetic proximity switches 61, 62, and 63 are turned on in order, and as described above, In each state, radio waves having different frequencies of 3 kHz, 3.2 kHz, and 3.5 kHz are transmitted from the transmitter 64 to the ground via the transmitting antenna 67, respectively. Although these frequencies are highly attenuated in the air, they are suitable frequencies for propagating in the ground due to the moisture contained in the ground. Of course, as long as it propagates in the ground, it is not particularly limited to the frequency of this embodiment, and for example, it can be used in an ultra-long wave region of several Hz to several tens of kHz. However, it is preferable to select several kHz due to the design of the transmission circuit. When the magnet 36 comes to any of the magnet type proximity switches 61, 62, 63, the radio wave is transmitted for the first predetermined period (about 2 seconds), and then the magnet 36 emits the radio wave for the first predetermined period (about 2 seconds), and then the magnet 36 emits the magnet type proximity switch 61, 62. , 63, regardless of whether the magnifying excavation head 30 remains in the slightly open state, the medium open state, or the fully open state, the transmission is stopped. As a result, the radio waves transmitted from the plurality of transmission devices 6 attached to the expansion excavation heads 30 of the plurality of bottom expansion excavators 2 in different working states hardly overlap each other. Then, even if the expanded excavation head 30 continues to stay in any of the slightly open state, the medium open state, and the fully open state (particularly in the fully open state) (in the excavation work, it stays in the medium open state for a long time due to the hardness of the support layer, for example. It is possible that it will continue.) The radio waves will not continue to be transmitted, and power consumption can be suppressed. As a result, the size of the battery power supply can be reduced, and the size of the transmitter 64 can be suppressed.

When the transmission device 6 transmits radio waves in the slightly open state, the medium open state, and the fully open state of the enlarged excavation head 30, it encodes its own unique identification information and digitally modulates each transmission frequency. , The signal of the identification information is put on the carrier wave of the frequency in each state of the expanded excavation head 30 and transmitted. When the receiving device 8 receives the radio wave, the receiving device 8 decodes the demodulated digital signal to extract the identification information of the transmitting device 6, and determines the state of the enlarged excavation head 30 according to the frequency of the received radio wave, so that the receiving device 8 is in a slightly open state. Informs the operator of the state of the magnified excavation head 30 with sound and light according to the medium open state and the fully open state (for example, in the small open state, the buzzer sounds and the blue lamp blinks at 1 second intervals, and the medium open state. In the state, the buzzer sounds and the yellow lamp blinks at 0.5 second intervals, and in the fully open state, the buzzer sounds and the red lamp blinks at 0.2 second intervals.) Then, the receiving device 8 identifies from which of the plurality of transmitting devices 6 the received radio wave is transmitted from the identification information of the extracted transmitting device 6, and specifies each transmitting device 6 according to the output target. Convert to a signal. Based on this signal, for example, the unique number of the transmitting device 6 is displayed on the display of the display unit 85 of the receiving device 8, or the excavator number of the bottom expansion excavator 2 to which the transmitting device 6 is attached is displayed. Further, it outputs a signal suitable for the interface of the control unit 24 or the management device 9 of the bottom expansion excavator 2 to which the transmission device 6 is attached. Here, in the present embodiment, the output unit 84 of the receiving device 8 is configured to wirelessly transmit a signal to the control unit 24 and the management device 9 of the bottom-expanding excavator 2, but of course, it may be wired. do not have. With this configuration, although there are a plurality of transmitters 6 and only three frequencies of radio waves are used, each transmitter 6 and eventually those transmitters 6 are attached. The expansion excavator head 30 and the bottom expansion excavator 2 can be distinguished without being confused.

The control unit 24 of the bottom-expanding excavator 2 outputs information on the opening degree (small open state, medium open state, fully open state) of the expanded excavation head 30 sent from the transmission device 6 attached to its own expanded excavation head 30. When received from the receiving device 8 separately from the information on the expanded excavation head of other bottom-expanding excavators, the progress of excavation work such as the excavation depth, the number of rotations of the expanded excavation head, the direction of rotation and the torque, and the state of the expanded excavation head 30. Are associated and recorded, and reflected in the control of subsequent excavation work.

At the same time, each time the management device 9 receives information on the opening degree (small open state, medium open state, fully open state) of the expanded excavation head 30 from the output signal of the receiving device 8, the management device 9 is accompanied by the information. Using the signal representing each transmission device 6 based on the identification information of 6, the opening degree of the expansion excavation head 30 is set for each transmission device 6, that is, for each bottom expansion excavator 2 to which the transmission device 6 is attached. The state is monitored, and it is recorded whether or not each bottom expansion excavator 2 finally excavates the bottom expansion portion D properly. Further, the management device 9 can also receive information from the control unit 24 of each bottom-expanding excavator 2, whereby all the bottom-expanding excavators 2, 2 ... It can be monitored, managed, and controlled as needed while identifying the situation.

As described above, according to the present invention, it is possible to wirelessly confirm whether or not the expanded excavation heads 30 of the plurality of bottom-expanding excavators 2, 2 ... Have expanded, and each of the expanded excavation heads 30. Although the frequency for transmitting the state is the same in all the transmitting devices 6, all the transmitting devices 6 can be identified based on the identification information without being confused by interference. Then, when the expanded excavation head 30 reaches a predetermined state such as a fully open state, radio waves are transmitted for a predetermined period such as several seconds, so that the radio waves transmitted from the plurality of transmitting devices 6 are distinguished without overlapping. Moreover, the power consumption can be suppressed and the size of the battery power supply and the transmitter 64 can be reduced. As a result, the range of choice of the enlarged excavation head 30 that can be attached so that the transmission device 6 does not get in the way is widened, and the enlarged excavation head 30 for a small diameter required for deep excavation can be used. Then, according to the present invention, it is individually identified what kind of excavation work progress the plurality of bottom-expanding excavators 2, 2 ... Are in, and what kind of state each of the expanded excavation heads 30 is in. It can be monitored, managed and controlled as needed.

In this embodiment, individual frequencies are applied according to each state of the expanded excavation head, but the state of the expanded excavation head is also converted into a digital signal, and the state of the expanded excavation head 30 is only one frequency. And the identification information may be transmitted as a digital signal.

Further, in this embodiment, three states of the expanded excavation head, a slightly open state, a medium open state, and a fully open state, are detected, but basically, if the fully open state is known, the state in the middle is unknown. But it doesn't matter. As a result, power consumption can be further reduced. Also, when the expansion excavator head is removed from the bottom expansion excavator and laid down, the switch does not turn on even if the expansion excavator head naturally becomes a slightly open state, a medium open state, or a fully open state. The attitude control relay may be built in. This can prevent wasteful consumption of electric power.

Also, since the blade expansion bits are provided in pairs, it is sufficient to arrange the magnetic proximity switch on the side of one blade expansion bit, but if they are arranged in the same way on both sides, the head condition can be more reliably determined. Needless to say, it can be grasped.

Further, although the magnet type proximity switch is used in this embodiment, it is not necessary to use the magnet type proximity switch as long as it detects the movement of the magnified excavation head.

For the expanded excavation head, in addition to the one that expands the blade expansion bit by the earth pressure received when the head is reversed as in this embodiment, the hook pin is removed by temporarily reversing the head, and the normal rotation is continued as it is. There are various types such as those that expand the head by this, and those that expand by hydraulic pressure, but it is only necessary to be able to grasp the state of the expanded excavation head by using the movement of the moving part when the expanded excavation head expands. The underground propagation signal transmission / reception device of the present invention does not select the type of the magnified excavation head to which the transmission device is attached.

Of course, the transmitter of the transmitter may be installed inside the magnified excavation head, or may be mounted on the peripheral surface of the drive pipe near the magnified excavation head so as to avoid a screw (not shown) that assembles mud generated during excavation. .. In this case, the shape of the casing may be a rounded shape that is less susceptible to the resistance of the mud that is scraped up. When the transmitter is attached to the outside, it is advantageous in that maintenance (for example, battery replacement) becomes easy.

Further, one receiving device may receive radio waves from a plurality or all of the bottom-expanding excavators, or one receiving device may be provided for one bottom-expanding excavator. As long as the radio waves from each transmitting device can be received by any receiving device, the number of receiving devices and the arrangement of the receiving antennas thereof do not matter. However, while weakening the output so that strong radio waves do not leak into the air, the distance between the transmitting device and the receiving device is reduced, and one receiving device corresponds to one transmitting device. It may be advantageous to do so.

Further, there are many methods of excavation work such as a PC pile method and a cast-in-place pile method, but it goes without saying that the present invention is not limited to any of the methods.

Further, although the excavation work has been mainly described here, the present invention is applied to all the works in which the head portion at the tip performs the work in the ground and the state of the head portion in the ground needs to be grasped on the ground. It is possible. For example, when it is necessary to grasp the pressure state received by the head part or the temperature state of the head part, when the predetermined pressure or temperature is reached, the pressure / temperature detection is used as a trigger to transmit radio waves from the transmitting device. It may be configured as follows. In any case, the information on the state of the head portion can be transmitted together with the unique identification information possessed by the transmission device, and the information can be used for the identification and management of the head portion for underground work or the underground work machine.

Further, in the above embodiment, the identification information of the transmitting device is transmitted by applying digital modulation using an analog sine wave as a carrier wave, but a pseudo alternating current is generated by alternately repeating positive and negative square waves. A signal (for example, 3 to 10 kHz) may be generated and used for a carrier wave radiated from an antenna by appropriately amplifying the signal. In this case, the CPU is mounted on the transmission device, and the program mounted on the CPU is arbitrarily rewritten to cause the CPU to generate a square wave having an arbitrary frequency and pulse width, and a carrier wave is generated based on the square wave. By using the control by this CPU, the carrier wave can be transmitted in a pulse width modulation manner (the time length and frequency of the part where the carrier wave is sent and the part where the carrier wave is not sent are changed), or can be transmitted in a digital modulation manner as described above. It is possible to transmit radio waves in all manners. Then, various information such as various information of the head part such as the rotation speed of the enlarged excavation head, excavation speed, horsepower, earth pressure, and soil hardness and information of the temperature inside the transmission device are freely generated by the CPU as a signal. It can be included and sent. Similarly, a CPU is mounted on the other receiving device, and information is acquired by analyzing the signal transmitted from the transmitting device. The advantage of such a circuit is that it uses less power, which further reduces the size of the battery and prolongs its duration.

Further, the transmitting device and the receiving device are provided with a calendar timer and a gyro sensor so that time and position information can be acquired, and the time and position data and the various information of the head portion are transmitted to the transmitting device and the receiving device. It may be stored in a data logger mounted on the receiving device and configured to be appropriately read from the interface (in order to reduce the recording capacity, only the time and the on / off of each sensor may be stored). With such a configuration, it can be used in various ways, for example, when the data of the transmitting device and the receiving device do not match, it is useful for investigating the cause of failure.

2 Excavator (underground work machine)
4 Transmission / reception device (underground propagation signal transmission / reception device)
6 Transmitter 8 Receiver 9 Management device 21 Construction machinery vehicle 22 Drive pipe (working department)
23 Pile joint part (working part)
24 Control unit 30 Enlarged excavation head (head unit)
31 Head body 32 Stopper 33 Tip bit 34 Wing expansion bit 35 Arm 36 Magnet 37 Pin 61 Magnet type proximity switch (small open state)
62 Magnet type proximity switch (in the middle open state)
63 Magnetic proximity switch (fully open)
64 Transmitter 65 Information signal converter 66 Modulator 67 Transmitter antenna 68 Insulation sheet 69 Circular belt type conductor 81 Receiver 82 Demodulator 83 Information signal converter 84 Output 85 Display 86 Receiver antenna 100 Expanded excavator 110 Expanded excavation Head 120 Tip bit 130 Blade expansion bit 140 Pin 150 Magnet 160 Magnet type proximity switch 170 Drive pipe A Pile hole P Casing pipe D Expanded bottom H Administration building S Excavation work system (underground work system)

Claims (10)

An underground propagation signal transmitter / receiver used for an underground work machine having a head part for performing underground work at the tip of the work part.
A transmission device attached to the head portion, and when the head portion is in a predetermined state, a radio wave having a predetermined frequency of several Hz to several tens of kHz propagating in the ground is transmitted to the ground.
In an underground propagation signal transmitting / receiving device provided with a receiving device that receives the radio wave with an antenna inserted into the ground and generates an output signal corresponding to a predetermined state of the head portion.
The transmitting device is configured to transmit a signal based on the unique identification information of the transmitting device on the radio wave.
The receiving device is characterized in that the transmitting device having the identification information is specified based on the identification information obtained from the received signal, and the output signal is output together with the signal representing the specified transmitting device. An underground propagation signal transmitter / receiver. The transmitting device is characterized in that when the head portion is in a predetermined state, radio waves are transmitted for a predetermined period, and then transmission of radio waves is stopped regardless of whether or not the head portion is continuously in the predetermined state. The underground propagation signal transmission / reception device according to claim 1. The underground propagation signal transmission / reception device according to claim 1 or 2, wherein the transmission device transmits the identification information as a digital signal. A head portion provided at the tip of a work portion of an underground work machine for performing underground work, to which a transmitter of the underground propagation signal transmitter / receiver according to any one of claims 1 to 3 is attached. The head portion according to claim 4 is formed as an expansion excavation head provided at the tip of a work portion of an underground work machine as a bottom expansion excavator, and in the predetermined state, the expansion bit of the expansion excavation head is opened. A head portion characterized by being in a state. The head portion according to claim 4 or 5, wherein an individual frequency is applied according to each state of the enlarged excavation head. An underground work machine having the head portion according to any one of claims 4 to 6 at the tip of the work portion. The underground work machine according to claim 7 has a control unit for monitoring the progress of underground work, and the control unit is from a receiving device of the underground propagation signal transmission / reception device according to claim 1 or 2. An underground work machine characterized by receiving the output signal together with a signal representing the transmission device and recording the progress of the underground work in association with a predetermined state of the head portion. At least one receiving device of the underground propagation signal transmitting / receiving device according to any one of claims 1 to 3 .
A plurality of underground work machines according to claim 7 or 8 ,
A signal representing the transmitting device attached to each of the head portions of the plurality of the underground working machines is acquired from the receiving device (8), and the underground working machine is identified and identified based on the signal. A management device that monitors and / or records the predetermined state of the head portion of the underground work machine for each underground work machine.
Has an underground work system. A transmission device is attached to the head portion of an underground work machine having a head portion for performing underground work at the tip of the work portion, and when the head portion is in a predetermined state, the transmission device has information on the predetermined state. A signal based on the unique identification information is placed on a radio wave having a predetermined frequency of several Hz to several tens of kHz propagating in the ground and transmitted from the transmission device to the ground.
A radio wave carrying a signal based on the information of the predetermined state of the head portion and the identification information of the transmitting device is received by an antenna inserted in the ground .
The transmitter is identified based on the received identification information of the transmitter.
The head portion to which the identified transmitter is attached and the underground work machine having the head portion are identified.
Underground work management that manages the underground work by monitoring, recording, or controlling at least one of the predetermined states of the received head portion for each of the identified head portion or the underground work machine. Method.

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