JP2004132105A - Driving device for jacking method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique easily applicable to a driving device with a small caliber capable of facilitating the bending action of divided bodies constituting the driving device and, at the same time, surely preventing an undesirable twisting action. <P>SOLUTION: The driving device includes at least a pair of correcting jacks 50 expansible in the direction of the axis bilateral symmetrically arranged to a diametral line D extended in the direction of radiation from an intersection of the center axis C in a section at right angles to the center axis C at a connecting position of divided bodies 20 to 40 of the driving device 10 and connected to the divided bodies 20 to 40 in front and behind in a bendable manner and twisting prevention connectors 60 arranged on the diametral line D and fixedly connected in the circumferential direction of the divided bodies 20 to 40, although the divided bodies 20 to 40 in front and behind can be moved along the diametral line D and they can be also rotated in the spherical direction with the point on the diametral line D as the center. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a digging device, and more particularly, to a digging device that is propelled while forming a tunnel in the ground in a propulsion method.
[0002]
[Prior art]
As a digging device of the propulsion method, there is a digging device formed of a plurality of divided bodies that can be bent back and forth in order to correct or change the propulsion direction.
The excavating device having a cylindrical shape as a whole is divided into two or three bodies before and after along its central axis. The connecting portions of the front and rear divided bodies are provided with correction jacks arranged at a plurality of positions in the circumferential direction. If a difference is made between the amount of expansion and contraction at the correction jacks at a plurality of locations, the front and rear divided bodies bend. When the entire excavation device is propelled while the divided body is bent, the propulsion direction changes in a direction in which the foremost divided body of the excavation device faces.
[0003]
During the propulsion work, the propulsion direction deviated from the design line for some reason, such as deviation of resistance from the ground or deviation of the direction of thrust applied to the buried pipe line connected behind the excavation device In this case, the correction jack can be operated to return the propulsion direction to the correct design line. In the curve propulsion method, the excavating device is bent by the correction jack and propelled along the curve line according to the curvature of the design line.
The excavation device may bend not only horizontally in a horizontal plane but also vertically in a vertical plane. For example, there is a case where the burial depth of the buried pipe is gradually increased or decreased. Of course, it is necessary to correct when the propulsion direction is shifted in the vertical direction. Naturally, it is often necessary to combine the upper and lower sides and the left and right.
[0004]
In order to be able to arbitrarily bend the divided bodies of the digging device in any of the required vertical, horizontal, and oblique directions, use a spherical bearing or the like to connect the modified jack and the front and rear divided bodies. Then, it is desirable to be able to bend in any direction.
However, if the connection between the correction jack and the divided body is in a state in which the divided body can be bent in an arbitrary direction, not only can the front and rear divided bodies bend each other but also perform a movement in a twisting direction that rotates relatively in the circumferential direction. There is a problem.
If the divided bodies are twisted, the propulsion direction of the excavation device cannot be determined accurately. For example, even if the amount of expansion and contraction of the correction jack is set to bend the foremost divided body up and down and left and right by a predetermined angle in accordance with the desired propulsion direction, the divided body is twisted and the vertical lines of the upper and lower sides are adjusted. Once tilted, it cannot be bent in the set direction, and the propulsion direction changes.
[0005]
Therefore, a twist preventing means for preventing the divided bodies from twisting is required. It is conceivable to prevent torsion by using various pins, links, connection by a guide member or a bearing mechanism.
In addition, when the number of the correction jacks increases, the twisting hardly occurs. For example, if a large number of correction jacks are installed at intervals in the circumferential direction at the connection point between the divided bodies, the correction jacks will regulate the movement in the twisting direction of each other, and a large twist will occur. Absent.
[0006]
[Problems to be solved by the invention]
In the conventional technology for preventing twisting of a digging device, it has been difficult to reliably prevent only twisting without impairing the degree of freedom of bending between the divided bodies. In particular, no practical technology was found for a small-diameter excavation device.
The method of increasing the number of correction jacks to prevent twisting can be applied to a large-diameter excavator to which a large number of correction jacks can be mounted, but a small-diameter excavation apparatus to which only a few or two correction jacks can be mounted. Is difficult to apply. As the number of correction jacks increases, the cost of equipment increases and the cost of operating the digging device also increases.
[0007]
The present applicant has studied the technology shown in FIG.
A U-shaped fitting 112 is attached to one of the divided bodies 110 and a pin 102 is attached to the other 100, and the pin 102 is inserted into the U-shaped fitting 112 in advance. The pins 102 abut against the left and right inner surfaces of the U-shaped bracket 112 to prevent the divided bodies 100 and 110 from moving in the twisting direction. Since the pin 102 can be tilted or moved in the front-rear direction or moved or rotated in the axial direction with respect to the U-shaped bracket 112, bending between the divided bodies 100 and 110 can be allowed.
In the above-described combination structure of the pin 102 and the U-shaped bracket 112, a margin or play is required to allow the pin 102 to be inclined with respect to the U-shaped bracket 112 in order to freely bend the divided bodies 100 and 110. . Since the cylindrical pin 102 and the inner surface of the planar U-shaped bracket 112 are in line contact with each other, if there is no play, an excessively large load is locally applied, making relative movement difficult or the contact surface being cut. If it is severe or severe, the pins 102 and the U-shaped bracket 112 may be broken.
[0008]
6, there is a gap between the outer peripheral surface of the pin 102 and the inner peripheral surface of the U-shaped bracket 112. However, the play between the pin 102 and the U-shaped fitting 112 allows the split bodies 100 and 110 to twist. In FIG. 6A, the torsional movement in the direction of the dashed arrow cannot be sufficiently prevented.
Further, in the above structure, the pins 102 can move in the axial direction of the divided bodies 100 and 110 in a direction in which the pin 102 comes off from the U-shaped bracket 112. In this case, the divided bodies 100 and 110 are separated. Therefore, in addition to the connection by the U-shaped bracket 112 and the pin 102, means or a mechanism for connecting the divided bodies 100 and 110 in the axial direction is required. For example, by supporting a rod-shaped support member on the divided bodies 100 and 110 with spherical bearings, the axial movement of the divided bodies 100 and 110 is prevented while allowing bending. The device is complicated by the amount of the support member, and the internal space of the excavating device is reduced.
[0009]
It is an object of the present invention to provide a digging device having the above-mentioned divided structure, in which the divided bodies can be easily bent and undesirably twisted. In particular, it is an object of the present invention to provide a technique that can be easily applied to a small-diameter excavation device.
[0010]
[Means for Solving the Problems]
A digging device for a propulsion method according to the present invention is a digging device used for a propulsion method, in which a plurality of divided bodies are connected to each other in an axial direction so as to be freely bendable. It is arranged at a position that is bilaterally symmetrical with respect to a diameter axis that extends radially from the intersection with the central axis in a cross section orthogonal to the central axis of the device, is flexibly connected to the front and rear divided bodies, and expands and contracts in the axial direction At least one pair of correction jacks, which are free, are arranged on the diameter axis, which is the axis of symmetry of the left and right correction jacks, and the front and rear divisions can be moved along the diameter axis, and points on the diameter axis can be moved. A torsion-preventing connector is provided at the center which is rotatable in the spherical direction but is immovably connected in the circumferential direction of the divided body.
[0011]
[Drilling device]
Basically, a structure similar to a digging device used in a normal propulsion method is employed.
The diameter of the excavating device corresponds to the diameter of the buried pipe to be buried, but is usually set in the range of 25 to 300 cm. Particularly, it is useful for a digging device having a diameter of 50 to 300 cm. The total length of the digging device is usually set in the range of 1 to 6 m.
The excavation device is formed by connecting a plurality of divided bodies in the axial direction so as to be freely bendable with each other. The number of divided bodies is at least two of the front and rear, and may be three or more of the front part, the middle part and the rear part, or may be more than that. The divided bodies constituting the excavating device may all have the same length, or may have different lengths according to their functions.
[0012]
Each of the divided bodies accommodates various devices and members necessary for operating the excavating device of the excavating device or executing the propulsion method.
For example, a split body arranged at the forefront of a digging device is provided with a mechanism for digging or consolidating the ground. A mechanism for supplying muddy water or chemicals for excavation may be provided on the front face of the excavating device or the like. These device mechanisms may be arranged not only at the forefront division but also inside the rear division.
The divided body arranged at the rearmost part of the excavation device is provided with a connection structure of a buried pipe connected to the rear of the excavation device. Specifically, a bolt connection structure, a fitting structure, or the like is employed.
[0013]
A gap or a space is provided at a connecting point between the divided bodies to allow a bending motion of the divided body. A watertight structure is installed to prevent earth and sand from entering through the gaps and spaces. Specifically, a watertight structure in a normal civil engineering device such as a packing, an O-ring, and a water sealing device can be applied.
(Correct jack)
It has a function of bending the divided bodies. In addition, it also functions to connect the divided bodies so as not to be separated.
Basically, a structure similar to the correction jack of a normal digging device can be adopted. The correction jack has an operation structure that can be extended and retracted with respect to the main body structure. Specifically, it includes a cylinder portion that is a main body structure and a piston portion that is an operation structure. The piston unit can be operated by applying fluid pressure to the cylinder unit. The fluid pressure includes hydraulic pressure, pneumatic pressure, and water pressure. As the piston-cylinder mechanism, a mechanism can be used in which the piston portion operates to expand and contract from the front and rear of the cylinder portion disposed at the center.
[0014]
As the correction jack, one having a mechanical operation structure such as a toggle mechanism, a link mechanism, a gear mechanism, and a wire pulley mechanism in addition to the piston cylinder mechanism can be adopted. A combination of a fluid mechanism and a mechanical mechanism can also be employed. Operation by electromagnetic force is also possible.
The operating force of the correction jack is usually set in the range of 50 to 1000 kN. The extension length of the correction jack is usually set in the range of 2 to 30 cm.
The connection between the correction jack and the divided body may be performed by fixing the main body portion or the operating portion of the correction jack to the divided body, or by connecting the modified jack so as to be freely bent. At least one of the front and rear divided bodies is connected to bend freely. The term "flexible" refers to only one direction, left and right, up and down, right and left and up and down, and further to an arbitrary direction including an oblique direction.
[0015]
Usually, it is desirable to connect both ends of the correction jack to the divided body so as to bend in an arbitrary direction. As a result, the expansion and contraction force of the correction jack can be converted into a force for smoothly bending the divided body. A spherical bearing mechanism can be adopted as a means for connecting the correction jack and the divided body so as to be bent in an arbitrary direction.
[Arrangement of modified jack]
The correction jack is arranged at a connecting point between the divided bodies so that the divided bodies can be bent in the up-down direction, the left-right direction, and further in any direction.
Specifically, it can be arranged at a position which is symmetrical with respect to a diameter axis extending radially from an intersection with the central axis in a cross section orthogonal to the central axis of the excavating device. If the amount of expansion and contraction of the correction jack on the left and right of the diameter axis is changed, the divided bodies can be bent in the left and right directions. If the correction jack is arranged at a position vertically symmetrical with respect to the diameter axis, the divided bodies can be bent in the vertical direction. One of the correction jacks arranged symmetrically or vertically may be replaced with a simple connecting member that does not expand or contract, or may be replaced with a torsion-preventing connecting device.
[0016]
If at least two correction jacks are installed in a cross section orthogonal to the central axis at one connection point between the divided bodies, the divided bodies can be bent in an arbitrary direction if at least two correction jacks are installed. It can be installed in three or more. The correction jacks may be arranged at equal angles in the circumferential direction of the cross section, or may be arranged at irregular intervals. A plurality of correction jacks can be provided side by side at one location.
A correction jack may not be installed at the place where the anti-twisting connector or the connecting member is installed.
[0017]
For example, a pair of correction jacks and an anti-twist connector may be arranged at equal angles, ie, 120 degrees.
(Twist prevention connector)
It has the function of connecting the divided bodies to bendable. However, relative movement between the divided bodies in a specific direction is prevented.
The anti-twist coupling is located on a diameter axis which is the axis of symmetry of the correction jacks arranged on the left and right. The correction jacks are arranged symmetrically on the left and right sides of the diameter axis on which the anti-twist connector is arranged.
[0018]
The torsion preventing connector connects the divided bodies under the following conditions. First, the front and rear divided bodies are connected so as to be movable along the diameter axis. It is connected so that it can rotate in the spherical direction about a point on the diameter axis. The term “spherical direction” refers to a state in which rotational movement in any direction along the spherical surface is possible around the center of the spherical surface. The angular range of rotation need not be 360 degrees in any direction. It is only necessary that the rotation be possible to allow the bending angle required for the divided body. Normally, it is sufficient if the rotation can be made within a range of 3 to 20 degrees.
The torsion-preventing coupler connects the divided bodies immovably in the circumferential direction. The circumferential direction is a direction in which one divided body is twisted with respect to the other divided body. The term “immobile” means a state in which movement due to play or clearance can be substantially prevented. However, it is not necessary to prevent a small movement that is unavoidable industrially as long as the effects of the present invention are not impaired.
[0019]
In the torsion prevention connector, a member fixed to one of the divided bodies and a member fixed to the other divided body are usually connected in a state of allowing or preventing the movement of each other. In the connecting portion, if the members on both sides are slid in surface contact, the contact pressure is reduced and smooth sliding becomes possible. In the case of surface contact, smooth sliding becomes easy even if there is no play or room between members. As a specific sliding structure, a structure of a sliding mechanism or a sliding member in an ordinary mechanical device or the like can be adopted. A bearing mechanism such as a ball bearing or a fluid bearing may be employed.
<Twist prevention connector using spherical sliding>
A connector having the following structure can be adopted as a torsion-preventing connector that effectively performs the above functions.
[0020]
It has a sliding shaft that is fixed to one of the front and rear divided bodies and concentric with the diameter axis. The sliding shaft is preferably made of a material having rigidity such as a steel bar, and is made of a material having good slidability on the peripheral surface. A low friction material layer may be formed on the surface of the sliding shaft by a film forming means such as plating or thermal spraying. The sliding shaft generally has a circular cross-section, but a cross-sectional shape other than a circle, for example, an elliptical shape, an elliptical shape, a polygonal shape, and a gear-shaped or spline-shaped uneven cross-sectional shape can also be used. With a cross section other than a circular cross-section, movement around the axis of the sliding shaft and the spherical sliding ring can be prevented.
The spherical sliding ring has a ring shape as a whole, is inserted through the sliding shaft, slides in the axial direction, and has a spherical outer peripheral surface. The spherical sliding ring can be made of a material having excellent slidability, such as a bearing metal. Only the inner and outer peripheral surfaces of the spherical sliding ring may be formed of a low friction material layer. A small chip-shaped piece of low friction material can also be embedded and attached to the inner and outer peripheral surfaces.
[0021]
The inner peripheral surface of the spherical sliding ring has a cross-sectional shape corresponding to the outer peripheral surface of the sliding shaft. The outer peripheral surface of the spherical sliding ring has a structure in which a part of the spherical surface is cut off. The circumferential direction of the spherical sliding ring is a spherical surface within a range of 360 degrees, but the spherical surface is cut in the axial direction with a constant width. The inner peripheral surface of the spherical sliding ring and the outer peripheral surface of the sliding shaft can smoothly slide in the axial direction in a state where the entire surface is in surface contact.
The spherical slide receiving member is fixedly installed on the opposite divided body corresponding to the divided body on which the sliding shaft is installed. The spherical sliding ring is inserted to perform spherical sliding. The spherical sliding receiving member is formed of the same bearing material as the spherical sliding ring, or has a low friction material layer disposed on the inner surface. The inner peripheral surface of the spherical sliding receiving member forms a spherical surface corresponding to the outer peripheral surface of the spherical sliding ring. Practically, it suffices to slide at least on the outer peripheral surface of the spherical sliding ring within the range of the bending operation of the divided body to perform the connecting function of the divided bodies. For example, the thickness in the axial direction may be smaller than the thickness of the spherical sliding ring. Around the axis, a spherical slide receiving member that divides into a plurality of portions of the spherical slide ring and slides in contact with each other may be employed.
[0022]
The spherical sliding receiving member may be directly fixed to the divided body, or may be fixed to the divided body via a holding member or a supporting member for holding the spherical sliding receiving member. In this case, the holding member and the supporting member can be made of a structural steel material that is inexpensive and easy to process, so that the practicability is excellent.
[Arrangement of twist prevention connector]
The torsion-preventing couplers are arranged one by one at each coupling point of the divided body. The diameter axis is arranged in the extension direction of the sliding axis of the torsion preventing connector. The correction jacks are arranged symmetrically left and right with the diameter axis as a target axis. Further, the cross section of the excavating device may be divided into equal angles, and a plurality of correction jacks and a twist preventing connector may be arranged.
[0023]
When there are three or more divided bodies constituting the excavation device, that is, when there are two or more connection points, the arrangement structure of the torsion prevention connection tool and the correction jack is set to be the same at all the connection points. It can also be placed, and the arrangement structure may be different depending on the connection location.
For example, the anti-twisting connection and the correction jack can be arranged symmetrically in the direction of the diameter axis with respect to the central axis of the digging device at connection points arranged in front and behind. If there is an anti-twist connector at the upper connection point, the anti-twist connector is located at the lower connection point. The correction jack located below at the front connection point is arranged above at the rear connection point. When the correction jacks are vertically asymmetrically arranged at one connection point, the installation positions of the correction jacks at the front and rear connection points are staggered vertically. As a result, even with a digging device having a small space in the length direction, the front and rear correction jacks can be stably installed in a vertically staggered state. Interference between the front and rear correction jacks and their attached equipment can be prevented.
[0024]
[Operation of divided body]
When changing or correcting the propulsion direction of the excavating device, the divided bodies disposed in front and behind are bent at a predetermined angle and direction. This bending operation is performed by the expansion and contraction of the correction jack. The operation method and operation control of the correction jack can be performed in the same manner as a normal excavation device.
When the correction jack is expanded and contracted, the front and rear divided bodies approach and separate at the position of each correction jack. In the circumferential direction, the axial position of the front and rear divided bodies changes depending on the position of the correction jack, so that the front and rear divided bodies bend.
[0025]
The bending angle of the front and rear divided bodies is usually set in a range of 3 to 20 degrees.
At this time, at the position of the torsion preventing connector, the front and rear divided bodies relatively move along the diameter axis or rotate in the spherical direction around a point on the diameter axis. This allows the front and rear splits to bend in any direction. However, at the position of the torsion preventing connector, the divided bodies are immovably connected in the circumferential direction of the divided body, so that the front and rear divided bodies are prevented from being twisted.
If a torsion-preventive connecting device is installed at one connecting point in the circumferential direction, the front and rear divided bodies can be connected so that they can be bent and do not separate, so the connecting structure at a plurality of positions It is not necessary to provide a large-sized twist prevention structure. It is sufficient to provide only one twist prevention connector and the necessary correction jack at the connection point of the divided body, so it should be easily installed even on a small diameter excavation device without any problem Can be.
[0026]
In the minimum configuration, the split body can be flexibly bent with one twist prevention connector and a pair of correction jacks arranged symmetrically with the diameter axis passing through the twist prevention connector as the symmetric axis. Become. If the twist preventing connector and one correction jack are arranged at equal angles in the circumferential direction, the bending operation of the divided body can be performed efficiently.
If the torsion-preventing coupler is a combination of the above-described spherical sliding structure and shaft sliding structure, sliding by surface contact having a sufficient area is performed at the sliding point, and extra play and clearance are reduced. Even if it is not provided, it is possible to achieve smooth sliding and to sufficiently withstand a load or an external force applied to the connecting portion of the divided body. Moreover, the overall structure is relatively simple and easy to manufacture.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
The embodiment shown in FIGS. 1 to 4 shows a digging device composed of three divided bodies: a front part, a middle part and a rear part.
[Overall structure of excavation device]
As shown in FIG. 1 and FIG. 2, the excavating device 10 accommodates necessary structural members and equipment devices inside a cylindrical outer structure constructed entirely of steel or the like. Specific dimensions of the excavation device are set to, for example, a diameter of 150 cm and a total length of 4 m. The excavating device 10 is divided along the central axis C into three parts: a front divided body 20, an intermediate divided body 30, and a rear divided body 40. The lengths of the divided bodies 20 to 40 are set to, for example, 150 cm for the front divided body 20, 100 cm for the intermediate divided body 30, and 150 cm for the rear divided body 40.
[0028]
The front divided body 20 has an excavator 22 on the front surface, and the excavator 22 is rotationally driven from the front divided body 20 by a motor 24 housed in the internal space of the intermediate divided body 30. The excavating device 10 is propelled while excavating the ground with the excavator 22.
A buried pipe 70 for propulsion burying is connected to the rear end of the rear divided body 40. Although not shown, the buried pipes 70 are sequentially added rearward to form a buried pipe row.
Inside each of the divided bodies 20 to 40, as equipment necessary for the operation of the excavating device 10, a power line for supplying a driving power of a motor, a muddy pipe for supplying muddy water to a ground excavation surface, and excavated earth and sand Pipes to discharge the wastewater together with muddy water, and a surveying device for the propulsion position are accommodated and installed as necessary.
[0029]
[Arrangement of modified jack and twist prevention connector]
A pair of two correction jacks 50, 50 and a twist preventing connector 60 are arranged at the connecting portions of the divided bodies 20 to 40, respectively.
FIG. 2 (a) shows the modified jacks 50, 50 and the anti-twist connector 60 in a cross section orthogonal to the center axis C of the excavating device 10 at the connection point between the front divided body 20 and the intermediate divided body 30. 3 shows an arrangement structure.
The correction jack 50 and the torsion prevention connector 60 are arranged at positions near the inner surfaces of the cylindrical outer shells of the divided bodies 20 and 30, and various pipes and equipment installed in the central space of the divided bodies 20 and 30 are provided. So as not to interfere with the installation of
[0030]
A pair of correction jacks 50, 50 and a twist prevention connector 60 are arranged so as to form an equal angle θ with respect to the center axis C. The angle θ is 360/3 = 120 °. In addition, correction jacks 50, 50 are arranged at symmetrical positions on the left and right sides with respect to the diameter axis D connecting the center of the torsion prevention connector 60 and the center axis C. As shown in FIG. 1, a pair of correction jacks 50, 50 and a twist preventing connector 60 are also arranged at the connecting portion between the intermediate split body 30 and the rear split body 40, as described above.
However, the positional relationship between the correction jacks 50, 50 and the twist prevention connector 60 is different. In the cross-sectional structure of FIG. 2B, the correction jacks 50 and 50 are arranged on the upper side, and the torsion preventing coupler 60 is arranged on the lower side. The connection point in FIG. 2A is exactly symmetrical. By employing such an arrangement structure, the correction jacks 50 that require a relatively long length in the front-rear direction can be arranged so as to be staggered up and down at the front and rear connection points. As a result, in the excavating device 10 in which the internal space is narrow and a large number of devices must be efficiently arranged, the modification jack 50 can be efficiently arranged.
[0031]
[Structure of modified jack]
As shown in FIG. 3, the correction jack 50 has piston portions 54, 54 attached to both ends of a cylindrical cylinder portion 52. The respective piston portions 54, 54 advance and retreat with respect to the cylinder portion 52, and the distance between both ends of the piston portions 54, 54 expands and contracts. As a specific specification of the modified jack 50, for example, a modified jack that can generate an operating force of 1000 kN by hydraulic drive and have an expansion and contraction length of 20 cm can be adopted.
The tip of the piston 54 is a spherical end 56. A spherical bearing body 58 that receives the spherical end portion 56 is fixed to the inner surface of the outer structure of the divided bodies 20 to 40. The spherical bearing bodies 58 arranged at both ends are separately fixed to the divided bodies 20 and 30 or 30 and 40 arranged before and after.
[0032]
The spherical end 56 smoothly slides on the spherical bearing body 58. As a result, the piston 52 can be bent in any direction with respect to the spherical bearing 58 and the divided bodies 20 to which the spherical bearing 58 is fixed. With respect to any of the spherical bearing bodies 58 on both sides, the central piston portion 52 and the cylinder portion 54, that is, the entire correction jack 50 can be bent in an arbitrary direction. It is possible to allow the front and rear divided bodies 20 to 40 to bend in any direction by expanding and contracting the correction jack 50.
However, such connection by the correction jacks 50 cannot prevent the front and rear divided bodies 20 to 40 from moving in the directions in which they are twisted with each other.
[0033]
(Connecting structure)
FIGS. 4 and 5 show a detailed structure of a connecting portion between the front divided body 20 and the intermediate divided body 30 and a structure of a torsion-preventing connecting device 60 installed there.
At the connecting point between the front divided body 20 and the intermediate divided body 30, the front end 32 of the intermediate divided body 30 has a slightly smaller outer diameter than other parts and is narrowed. A sliding ring 34 is provided at the tip of the tip 32. The outer peripheral surface of the sliding ring 34 has a spherical shape centered on the central axis C of the intermediate divided body 30. A plurality of packings 26 are mounted on the inner peripheral surface of the front divided body 20 facing the sliding ring 34. The packing 26 comes into contact with the sliding ring 34 of the intermediate divided body 30 to exhibit watertightness. Even when the front split body 20 and the intermediate split body 30 are bent, the sliding ring 34 having the spherical outer peripheral surface and the packing 26 are kept in good contact with each other. There is no loss.
[0034]
Further, a fin 28 that is elastically deformable is attached to the rear end of the front divided body 20. Since the tip of the fin 28 abuts on the outer peripheral surface of the sliding ring 34, foreign matter such as earth and sand can be prevented from entering between the sliding ring 34 and the front split body 20.
The connection structure described above is also provided at a connection point between the intermediate divided body 30 and the rear connection body 40.
(Twist prevention connector)
As shown in FIGS. 4 and 5, a sliding shaft 61 that constitutes a part of the torsion preventing connector 60 is fixedly installed on the inner surface of the sliding ring 34 of the intermediate divided body 30. The center axis of the sliding shaft 20 is concentric with the diameter axis D extending radially from the position of the center axis C in a cross section orthogonal to the center axis C of the excavating device 10. The center axis C exists on the extension of the tip of the sliding shaft 20.
[0035]
The structure installed on the side of the front divided body 20 of the torsion preventing coupler 60 first has a support member 62 fixed to the inner surface of the front divided body 20 and extending in the direction of the central axis C of the excavating device 10. . The support member 62 has a holding member 64 extending from the side surface of the support member 62 toward the intermediate divided body 30 and having a hole in the center.
At the center of the holding member 64, a spherical slide receiving member 67 made of a bearing metal or the like having good slidability and having an overall annular shape and a spherical inner peripheral surface is attached. The center of the spherical surface of the spherical slide receiving member 67 is on the diameter axis D.
A spherical sliding ring 68 is accommodated inside the spherical sliding receiving member 67. The spherical sliding ring 68 is also made of a bearing metal having good slidability. The outer peripheral surface of the spherical slide ring 68 has a spherical shape corresponding to the inner peripheral surface of the spherical slide receiving member 67 and slides smoothly with each other. This slide is a spherical slide centered on the diameter axis D.
[0036]
The inner peripheral surface of the spherical sliding ring 68 is a circular hole corresponding to the inner diameter of the sliding shaft 61, and is inserted through the sliding shaft 61. The sliding shaft 61 and the spherical sliding ring 68 slide in the axial direction of each other, that is, along the diameter axis D.
Further, a disc-shaped cover 66 is attached to the lower end surface of the holding member 64. Above the cover 66, the space between the spherical slide receiving member 67, the spherical slide ring 68, and the slide shaft 61 is filled with grease to improve the slidability of each sliding portion. An annular covering member is also attached to the upper end surface side of the holding member 64, so that foreign matter hardly enters the sliding portion.
[0037]
The torsion-preventing coupler 60 having the above-described structure allows the front divided body 20 and the intermediate divided body 30 to slide on a spherical surface about the center of the spherical surface on the diameter axis D. In addition, linear movement along the diameter axis D is also allowed. However, the back-and-forth movement along the direction orthogonal to the diameter axis D, that is, the center axis C and the torsional movement around the center axis C are prevented.
As specific specifications of the torsion prevention coupling 60, for example, the diameter of the sliding shaft 61 is 20 cm, the spherical radius of the spherical sliding ring 68 is 30 cm, and the maximum sliding distance of the sliding shaft 61 with respect to the spherical sliding ring 68 is 5 cm. The rotation angle (vertical direction) between the spherical sliding ring 68 and the spherical sliding receiving member 67 can be set to 15 degrees.
[0038]
In addition, the twist preventing connector 60 arranged at the connecting portion between the intermediate divided body 30 and the rear divided body 40 has the same structure.
[Exercise at connected locations]
The movement of the front split body 20 and the intermediate split body 30 at the connection point provided with the twist preventing connector 60 and the correction jack 50 having the above structure will be described.
In FIG. 1, when the pair of right and left correction jacks 50 are simultaneously extended or contracted, the front divided body 20 and the intermediate divided body 30 are bent around the center of the spherical sliding of the torsion preventing connector 60. This is bending in the vertical direction.
[0039]
In FIG. 2A, when the expansion and contraction of the pair of right and left correction jacks 50 is reversed, the front divided body 20 and the intermediate divided body 30 are set with the sliding shaft 61 of the torsion preventing connector 60, that is, the diameter axis D as the rotation axis. Are bent in the horizontal direction.
By adjusting the direction of expansion and contraction of the pair of right and left correction jacks 50 and the amount of expansion and contraction, it is possible to bend in any direction combining the above-described vertical and horizontal bending movements.
When the bending motion as described above is performed, a relative movement is performed in which the distance between the sliding ring body 34 of the intermediate divided body 30 and the packing 26 of the front divided body 20 is increased or decreased. If the relative movement is too large, the watertightness is reduced. Since the central axis of the front divided body 20 and the central axis of the intermediate divided body 30 are shifted, the propulsion direction of the excavating device 60 is also largely shifted. This is because the center of the spherical sliding in the anti-twist connector 60 is on the diametric axis D which is distant from the central axis C.
[0040]
It is desirable that the front divided body 20 and the intermediate divided body 30 perform a bending motion such that the center of the bending is located on the central axis C.
Therefore, it is important that the sliding shaft 61 and the spherical sliding ring 68 slide along the diametric axis D in the torsion-preventing coupler 60. By allowing the sliding, the front divided body 20 and the intermediate divided body 30 naturally easily perform a bending motion such that the center of the bending is placed on the center axis C, and the sliding of the intermediate divided body 30 is facilitated. The distance between the moving ring 34 and the packing 26 of the front split body 20 does not fluctuate excessively.
Next, when excavation work is performed by rotating the excavator 22 of the front divided body 20 and the excavating device 10 is propelled, the front divided body 20 is moved around the central axis C by a reaction force due to resistance from the ground. The force to rotate acts on. A displacement force around the central axis C, that is, a torsional force acts between the intermediate divided body 30 and the front divided body 20 which are integrally connected to the rear row of buried pipes 70 or the like.
[0041]
However, since the relative movement of the sliding shaft 61 and the spherical sliding ring 68 and the spherical sliding receiving member 67 around the central axis C is prevented in the torsion preventing connector 60, the front divided body 20 is No torsional motion is performed on the intermediate divided body 30.
As a result, the front divided body 20 and the intermediate divided body 30 can freely and smoothly bend in any direction, while being prevented from twisting.
In addition, at the connecting portion between the intermediate divided body 30 and the rear divided body 40, the torsional movement is surely prevented while the bending movement similar to the above is allowed.
[0042]
【The invention's effect】
The excavation device for a propulsion method according to the present invention is provided with the twist prevention connector having the above structure, so that the bending motion of the divided bodies by the correction jack can be freely performed in any direction, while the circumferential direction of the divided body is Can be reliably prevented from being twisted.
As a result, the operation of correcting the propulsion direction of the excavator and performing curve propulsion can be performed accurately and smoothly, improving the work accuracy or work quality of the propulsion method, and greatly increasing demand for the propulsion method. You can contribute.
[Brief description of the drawings]
FIG. 1 is a side view of a digging device showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a connecting portion of a divided body.
FIG. 3 is a mounting structure diagram of a modified jack.
FIG. 4 is a partial cross-sectional side view of the anti-twist connector.
FIG. 5 is a partial cross-sectional bottom view.
FIG. 6 is a front view (a), a side view (b), and a plan view (c) showing a reference technique of a twist prevention mechanism.
[Explanation of symbols]
10 Drilling device
20 Front division
30 intermediate splits
40 Rear split
50 Modified jack
60 Torsion-preventing connector
67 Spherical slide receiving material
68 Spherical sliding ring
70 Buried pipe
61 Sliding shaft
C center axis
D Diameter axis

Claims (4)

A digging device used in a propulsion method, in which a plurality of divided bodies are flexibly connected to each other in an axial direction,
At a connection point of the divided bodies, the section is arranged at a position which is symmetrical with respect to a diameter axis extending radially from an intersection with the center axis in a cross section orthogonal to the center axis of the excavating device, and At least one pair of correction jacks that are connected to bendable and are extendable and contractible in the axial direction,
The front and rear divided bodies are arranged on the diameter axis, which is the axis of symmetry of the left and right correction jacks, and are movable along the diameter axis and rotatable around a point on the diameter axis in a spherical direction. An excavating device comprising: a torsion-preventing connector that is immovably connected in a circumferential direction of a body. The torsion prevention connector,
A sliding shaft fixed to one of the front and rear divided bodies and concentric with the diameter axis;
A spherical sliding ring having a whole annular shape, being inserted through the sliding shaft and sliding in the axial direction, and having a spherical outer peripheral surface,
The excavation device according to claim 1, further comprising: a spherical slide receiving member fixed to the other divided body, and into which the spherical slide ring is inserted to slide spherically. The excavating device according to claim 1 or 2, wherein the torsion preventing connector and the correction jack are arranged at an equiangular position with respect to an intersection with the central axis in a cross section orthogonal to the central axis of the excavating device. At least three of the divided bodies are connected,
At the connecting point between the front divided body and the intermediate divided body, and at the connecting point between the intermediate divided body and the rear divided body, the torsion preventing coupling tool and the correction jack are arranged with respect to the center axis of the excavating device. The excavating device according to any one of claims 1 to 3, wherein the excavating device is disposed at a symmetric position in a direction of the diameter axis.

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