JP4351871B2 - Pipe propulsion machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention includes a leading conductor having a cutter head in the front and a buried pipe attached to the rear end, excavating a natural ground with the cutter head while propelling the leading conductor and injecting a viscosity-imparting liquid into the excavated soil. The present invention relates to a pipe propulsion device that generates mud with plastic fluidity, sends the mud backward, takes a part of the mud from the rear of the leading conductor, discharges it to the ground, and guides the rest to the outer periphery of the buried pipe.
[0002]
[Prior art]
As a method for embedding a pipe in the ground, a method called a pipe propulsion method is conventionally known. In this pipe propulsion method, buried pipes formed of fume pipes, etc. are sequentially connected behind the leading conductor having the cutter head, and these are buried by a main pushing device having a main pushing jack and a pushing stand and installed in the starting shaft. In general, a method is used in which a buried head is excavated with a cutter head while pushing the pipe, and each buried pipe is sequentially pushed into the ground and buried. The pipe propulsion device is an apparatus composed of a leading conductor and a main pushing device in order to carry out such a pipe propulsion method.
[0003]
In this type of pipe propulsion machine developed by the applicant in the past, plastic fluid fluid mud is generated by injecting the additive as a viscosity-imparting liquid into the excavated soil and agitating and mixing it with the excavated soil excavated by the cutter head. Then, the mud is sent backward, a part of the mud is taken from the rear part of the leading conductor and discharged to the ground by a sand pressure feeding device, and the rest is guided to the outer periphery of the buried pipe attached to the rear end part of the leading conductor. Yes. In that case, the excavation outer diameter of the cutter head is made sufficiently larger than the outer diameter of the leading conductor body, and the support member supported by contacting the ground is provided on the outer periphery of the leading conductor body, thereby allowing the mud to pass through. For this reason, a sufficiently large gap is secured on the outer periphery of the leading conductor body so that a sufficient amount of mud can be guided to the outer periphery of the buried pipe. Therefore, when propelling the buried pipe, the frictional resistance between the buried pipe and the surrounding ground can be reduced to reduce the penetration resistance of the buried pipe, and the excavated sediment can be easily discharged by the earth and sand feeding device.
[0004]
As such a pipe propulsion machine, the applicant recently provided a cylindrical support member supported by a natural ground around the pipe body as the leading conductor body so as to form a mud passage, and the leading conductor. Developed a pipe propulsion machine with This pipe propulsion machine has a cylindrical support member and a large support area when supporting the tip conductor with a natural ground, so the posture of the tip conductor is stable, even when used in a soft ground belt, It has many advantages such as a sufficient posture support reaction force. An invention relating to this pipe propulsion device is described in Patent Document 1. The structure of the pipe propulsion device described in Patent Document 1 is difficult in that a large amount of mud and groundwater enter the start shaft when starting.
[0005]
In order to solve such problems, the applicant subsequently proposed a pipe propulsion device improved from the pipe propulsion device described in Patent Document 1, and the invention relating to this pipe propulsion device was filed as Japanese Patent Application No. 2001-276770. Did. In order to solve the above problems, the invention relating to this pipe propulsion device is provided with a mud passage closing device attached to the rear of the pipe body as the leading conductor body. In an example in which this pipe propulsion device is embodied, a spacer member having an arcuate cross section for fixing a cylindrical support member to the pipe body so that a mud passage is formed, and a pipe body so that a mud mud circulation gap is formed. It is arranged vertically and horizontally with an interval in the circumferential direction. In addition, a mud passage closing device is configured by providing a bowl-shaped elastic body that can be selectively closed and opened by the expansion and contraction of the supply and discharge of the pressure fluid. A plurality of elastic bodies are arranged so that a plurality of mud flow gaps between the spacer members can be closed respectively, and in combination with the spacer members, the mud passages can be closed when the pipe propulsion unit starts. Yes.
[0006]
By the way, the distribution gap of the mud between the spacer members for closing with this elastic body has an arc shape in which the cross section has corners in the vertical and horizontal directions. In order to sufficiently seal the flow gap of mud with such a cross-sectional shape with a bowl-shaped elastic body up to the corner, the elastic body should fit the cross-sectional shape of the mud flow gap. In order to be able to be deformed, it is necessary to produce a product with high followability, which is difficult in production. Therefore, in order to economically implement the invention of the above-mentioned patent application, a structure in which the elastic body is formed in an annular shape and the mud passage having a cross-sectional donut shape is closed by the annular elastic body alone regardless of the spacer member. I decided to adopt it.
[0007]
In order to facilitate understanding of the features of the present invention, here, a pipe propulsion device provided with such a mud passage closing device using an annular elastic body is positioned as a conventional technology, and the technical contents of this conventional technology are shown in FIG. Details will be described below with reference to FIG. FIG. 6 is a longitudinal sectional view of an essential part of a conventional pipe propulsion device when the elastic body is contracted before starting, and FIG. 7 is a transverse sectional view of an essential part of the pipe propulsion unit of FIG. 8 is a longitudinal sectional view of a main part of a conventional tube propulsion device when the elastic body is expanded at the start, and FIG. 9 is a conventional tube when the elastic body is contracted after the start is completed. FIG. 10 is a longitudinal sectional view showing a state in which a conventional pipe propulsion device is started in a start shaft, in the main part of the propulsion device.
[0008]
In these drawings, 1 is a cylindrical front inner pipe having a cutter head 7 in the front, 2 is a cylindrical rear inner pipe to which a buried pipe is attached via a connecting pipe 5 in the rear, and 3 is a front inner pipe 1. Cylindrical front and outer pipes 4 attached at intervals around the periphery, 4 is a cylindrical rear and outer pipe attached at intervals around the rear inner pipe 2 and the connecting pipe 5, and 5 is the rear inner pipe 2. A connecting pipe 6 for connecting a buried pipe, attached to the rear end, is formed between the outer circumferences of the inner pipes 1 and 2 and the connecting pipe 5 and the inner circumference of the outer pipes 3 and 4 for passing mud. A mud passage, 7 is a cutter head that is driven to rotate and excavates a natural ground ahead, 8 is a mud intake port that is provided in the lower peripheral wall of the rear inner pipe 2 and takes mud in the mud passage 6, and 9 is a rear of the rear inner pipe 2 The mud mud connected to the rear pipe 2 and pumped by a sediment pump (not shown) in the rear inner pipe 2 is guided to the ground via the start shaft 18. A drainpipe.
[0009]
The front inner pipe 1 and the rear inner pipe 2 are formed such that the outer diameters of both the pipes 1 and 2 are smaller than the excavating outer diameter of the cutter head 7. In addition, the front inner tube 1 and the rear inner tube 2 are fitted with an adjacent end portion through a folding seal (not shown) so as to be swingable, and at least three middle foldings arranged in the circumferential direction. They are connected by a jack (not shown) so that the pipes 1 and 2 can be bent vertically and horizontally by the stroke difference of these bent jacks. The front outer tube 3 and the rear outer tube 4 are arranged so that when the front inner tube 1 and the rear inner tube 2 are bent in this way, the adjacent end portions are arranged so as to be able to perform the bending operation following this operation. They are separated with a slight gap so as not to interfere with each other.
[0010]
The front outer pipe 3 and the rear outer pipe 4 are formed so that an annular mud passage 6 is formed between the front inner pipe 1, the rear inner pipe 2 and the connecting pipe 5, respectively. A fixed spacer is attached with a spacer (not shown) at an interval on the outer periphery of the lens. The front outer tube 3 and the rear outer tube 4 function as a supporting member that supports the leading conductor by being supported by the natural ground in addition to the function of forming the mud passage 6. The front outer tube 3 and the rear outer tube 4 as the cylindrical support members are formed to have substantially the same diameter as the excavation outer diameter of the cutter head 7 here, but the front inner tube 1 and the rear inner tube 2. If the mud passage 6 is formed with an interval sufficient to allow the necessary amount of mud to pass therethrough and the outer diameter of the cutter head 7 does not substantially exceed the outer diameter of the excavation, the excavation is not necessarily performed. It is not necessary to form the same diameter as the outer diameter.
[0011]
The cutter head 7 is provided with an additive injection hole (not shown) so as to radially inject an additive as a viscosity-imparting liquid at the center of the front end, and the additive injected from the additive injection hole The agent is agitated and mixed with the excavated soil so that mud soil with plastic fluidity can be generated. This mud is sent backward by an annular mud passage 6 and a part of the mud is taken into the rear inner pipe 2 from the mud taking-in port 8, and is then discharged by the earth pressure pump in the rear inner pipe 2. Through the ground. In FIG. 10, such mud is represented by the symbol M.
[0012]
The connecting pipe 5 serves to connect the buried pipe to the rear of the rear inner pipe 2 by fitting a buried pipe (not shown). Therefore, a buried pipe fixing portion 5 a for fitting and fixing the buried pipe is attached to the rear end portion of the connecting pipe 5. The buried pipe is connected to the rear of the rear inner pipe 2 in the start shaft 18 and is propelled by the main pushing device 10 in the start shaft 18 while being sequentially added. At that time, the soil discharge pipe 9 is successively added to the rear of the rear inner pipe 2 in a state of being laid inside the buried pipe 7. In this prior art tube propulsion machine, a front inner tube 1, a rear inner tube 2 and a connecting tube 5 are provided to constitute a leading conductor body, and a front outer tube 3 and a rear outer tube 4 are provided on the leading conductor body. It is provided and constitutes a leading conductor. In addition, a pipe propulsion device is configured by the leading conductor and the main pushing device 10 described below.
[0013]
10 is a main pushing device for propelling the leading conductor and the buried pipe, 11 is a frame which is installed in the start shaft 18 and movably supports the pushing table 13, and 12 is a pushing jack which gives a propulsive force to the leading conductor 1 and the buried pipe. , 13 is a pedestal for transmitting the propulsive force of the main pushing jack 12 to push the leading conductor and the buried pipe, 14 is a pipe support member that is installed at the front end of the frame 21 and horizontally supports the leading conductor and the buried pipe, Is an entrance packing that seals the gap between the outer peripheral surface of the leading conductor and the natural ground at the start to prevent intrusion of groundwater, earth and sand, etc. into the start shaft 18, and 17 is an entrance packing mounting member for mounting the entrance packing 16, Is a start shaft that is the starting point for pipe burial.
[0014]
The main pushing device 10 includes a frame 11, a main pushing jack 12, a pushing table 13, and a pipe support member 14. A pair of frames 11 are provided on the left and right sides (in the direction perpendicular to the paper surface) at a predetermined interval in the starting direction of the leading conductor. Standing up. These jack support bases 11a are arranged so as to be supported by the well wall of the start shaft 18 and to take a reaction force when the leading conductor is propelled by the main push jack 12. A pair of main push jacks 12 are provided corresponding to the frame 11, and the piston rod portion is attached to the jack support 11a, and the cylinder portion is connected to the push stand 13 so that it can be moved in any direction. To do. The push table 13 is provided with a roller 13a at the lower end portion in order to smoothly move in the front-rear direction. The entrance packing 16 and the entrance packing mounting member 17 are provided around the start opening of the start shaft 18 and form a ring shape.
[0015]
When the cutter head 7 is rotationally driven while propelling the leading conductor with the main pushing device 10, the conventional pipe propulsion device having the above-described structure excavates a natural ground to form a drilling hole. Further, in the process of excavating the excavation hole in this manner, the viscosity imparting liquid is injected into the excavation soil and stirred and mixed by the cutter head 7 to generate mud with plastic fluidity, and this mud is sent backward. Then, the mud is press-fitted and filled into the annular mud passage 6 and passes through the passage 6, and a part thereof is taken into the mud intake port 8 provided in the rear inner pipe 2 and is pumped to the ground by the sediment pump. While being discharged, the remainder is guided to the outer periphery of the buried pipe attached to the rear end of the rear inner pipe 2 to form a mud layer. In this pipe propulsion machine, the leading conductor is supported on the ground by the front outer pipe 3 and the rear outer pipe 4 while digging while reducing the penetration resistance of the buried pipe by the mud layer formed on the outer periphery of the buried pipe.
[0016]
In that case, the front outer tube 3 and the rear outer tube 4 as support members for supporting the leading conductor in the ground are cylindrical and have a large support area, so that the posture stability is good and the ground to be constructed is constructed. Even if the mountain is soft soil, a sufficient posture support reaction force can be obtained, the gap between the mud passages 6 can be maintained well, and the mud can reach the rear side of the mud passages 6 sufficiently. In addition, after the start is completed, the gap between the outer peripheral surface of the buried pipe and the natural ground is sealed by the entrance packing 16, so that ingress of groundwater, earth and sand, etc. to the start shaft 18 can be prevented. These points are common to the pipe propulsion device described in Patent Document 1.
[0017]
However, before the start is completed, the gap between the outer peripheral surface of the front outer tube 3 and the rear outer tube 4 and the natural ground is sealed by the entrance packing 16, but the rear end opening of the mud passage 6 is in the start shaft 18. Therefore, in the pipe propulsion device described in Patent Document 1, it is inevitable that mud, groundwater, and the like infiltrate in a large amount into the start shaft 18 from the rear end opening through the mud passage 6 when starting. In order to solve such a problem, the applicant has proposed the invention of the patent application of the Japanese Patent Application No. 2001-276770 in which a mud passage closing device is attached behind the earth and sand intake port in the main conductor body as described above. In the prior art pipe propulsion device shown in FIGS. 6 to 10, when the invention of this patent application is carried out, in order to be able to manufacture the mud passage closing device without difficulty, the elastic body 24 constituting the closing device is provided. As described above, an annular structure was adopted.
[0018]
Therefore, the structure of the mud passage closing device 20 in this conventional pipe propulsion device, its problems, etc. will be described below.
[0019]
20 is a mud passage closing device for closing the mud passage 6, which is attached to the connecting pipe 5 that forms the last part of the leading conductor body, and 21 is between the inside of the elastic body 24 and the outer peripheral surface of the connecting pipe 5. A fluid enclosure chamber 22 that is formed and can enclose a pressure fluid, 22 is a fluid supply / discharge path using a hose for supplying pressure fluid to the fluid enclosure chamber 21 or discharging the pressure fluid from the fluid enclosure chamber 21, 23 Is an elastic body attaching member for attaching the elastic body 24 to the outer peripheral side of the connecting pipe 5, and 24 is an annular elastic member having an elastic deformation part 24a and a fixing part 24b and attached so as to surround the outer periphery of the connecting pipe 5. 24a is an elastic deformation part of the elastic body 24 which can be expanded and contracted to close and open the mud passage 6 respectively, and 24b is a flange shape fixed to the outer peripheral side of the connecting pipe 5 by an elastic body mounting member 23. Elastic body 24 Which is a fixed part.
[0020]
When a pressure fluid is supplied to the fluid sealing chamber 21 from a pump (not shown) through the fluid supply / discharge passage 22, the elastic body 24 expands so that the radial cross section of the elastic deformation portion 24a becomes semicircular as shown in FIG. Then, the mud passage 6 is closed. Further, when the pressure fluid in the fluid sealing chamber 21 is discharged through the fluid supply / discharge passage 22, when the external force is not acting on the elastic deformation portion 24a, the radial cross section of the elastic deformation portion 24a is as shown in FIG. The mud passage 6 is opened by contracting to become flat. As the pressure fluid, a desired fluid such as air or hydraulic oil can be used.
[0021]
The fixing portion 24b of the elastic body 24 is a portion that is fixed to the connecting pipe 5 and is inconvenient if it is deformed when the fluid is sealed in the fluid sealing chamber 21, so that the fixing portion 24b is formed to be more difficult to deform than the elastic deforming portion 24a. ing. The elastic body attaching member 23 includes a bolt and a clamping member for clamping the fixing portion 24 b of the elastic body 24 in cooperation with the connecting pipe 5. When the elastic body 24 is attached to the connecting pipe 5, after the annular elastic body 24 is fitted to the connecting pipe 5 using its elasticity before the fixing portion 5 a of the flange-like embedded pipe is fixed to the connecting pipe 5. After the fixing portion 24b of the elastic body 24 is sandwiched between the connecting tube 5 and the clamping member, the clamping member and the fixing portion 24b are screwed to the connecting tube 5 with bolts.
[0022]
In the prior art pipe propulsion device having such a structure, when starting, the mud passage 6 is closed by the mud passage closing device 20 provided behind the soil intake port 8. If it does so, it will become possible to take the mud produced | generated in the start process to the earth and sand intake port 8, and to discharge | emit it to the ground with an earth and sand pump. Therefore, the mud discharge amount can be controlled from the initial stage of the start by controlling the mud discharge amount with the sediment pump, and the face can be supported with the appropriate mud pressure. As a result, it is possible to prevent the collapse of the natural ground around the excavation hole and to suppress the groundwater from flowing around the face by mud pressure, so that safe construction can be performed. Further, since the mud passage 6 is closed by the mud passage closing device 20, it is possible to prevent mud and groundwater from entering the start shaft 18 from the rear end opening of the mud passage 6. After the start is completed, the rear end opening of the mud passage 5 is isolated from the starting shaft 28 by the entrance packing 16, so that the mud passage closing device 20 can be opened to perform normal excavation.
[0023]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-2094 (page 4-6, FIG. 1)
[0024]
[Problems to be solved by the invention]
By the way, it is necessary for the mud passage 6 to maintain a cross-section through which the mud can easily pass through with a passage resistance lower than the mud pressure. Otherwise, the mud does not spread evenly around the outer periphery of the buried pipe. The penetration resistance of buried pipes during pipe propulsion cannot be effectively reduced. Therefore, the mud passage 6 has a structure in which the mud is difficult to pass through and the mud is not allowed to pass through, and foreign matter (pebbles, etc.) in the mud and highly viscous earth and sand are not easily deposited, so that the mud flow is not obstructed. It is necessary to. For this reason, in the conventional pipe propulsion device, the radial cross section is flattened so that the elastically deformable portion 24a is as flush as possible with the inner peripheral surface of the mud passage 6 when the elastic body 24 is contracted. Accordingly, the mud passage closing device 20 is configured so that a convex portion that narrows the mud passage 6 and a concave portion that is likely to accumulate such as earth and sand are not formed in the mud passage 6.
[0025]
However, when the elastic body 24 is contracted, the mud passage closing device 20 has a flat cross section in the radial direction of the elastic deformation portion 24a as shown in FIG. At the time of normal excavation after the completion, mud pressure acts on the elastic deformation portion 24a, so that the elastic deformation portion 24a is deformed so that a depression is formed in the center portion as shown in FIG. When such a depression is formed in the elastic body 24, foreign matter in the mud, highly viscous earth and sand, etc. accumulate in this depression, and the flow of the mud is inhibited by these deposits. Further, when the flow of mud is obstructed and the flow velocity decreases, the mud is easily clogged not only in the elastic body 24 but also in the mud passage 6. Will not be able to excavate excavated earth and sand, making it impossible to excavate.
[0026]
In order to avoid such a situation, the elastic deformation portion 24a is prevented from being depressed by enclosing a highly incompressible fluid in the fluid sealing chamber 21 so that the flat state of the elastic deformation portion 24a can be maintained against mud pressure. However, if the fluid supply / discharge path 22 connecting the fluid supply source on the ground and the fluid sealing chamber 21 becomes longer as the leading conductor advances, the elastically deforming portion 24a will inevitably generate fluid supply. It is difficult to prevent the elastic deformation portion 24a from being depressed because it is deformed by a slight expansion of the drainage passage 22 and a slight contraction of the fluid inside thereof. Furthermore, when the elastic deformation portion 24a is pressed with a hard foreign material such as gravel, it is no longer possible to prevent the deformation of the elastic deformation portion 24a, and the foreign material is accumulated in the depression caused by the deformation. As a result, the mud passage 6 is blocked, and the mud flow in the mud passage 6 is obstructed.
[0027]
The present invention was created in order to solve these problems found in the prior art, and the technical problem was that a cylindrical support member was provided to form a leading conductor and a mud mud passage closing device was attached. It is an object of the present invention to provide a pipe propulsion device in which it is not difficult to manufacture a mud passage closing device and the mud flow is not hindered by the attachment.
[0028]
[Means for Solving the Problems]
These technical problems of the present invention are:
A tubular front conductor body with a cutter head in the front and a buried pipe attached to the rear end, and a ground fixed to the outer periphery of the front conductor body so as to form a mud passage for passing mud. It has a tip conductor composed of a cylindrical support member supported by a mountain, and excavates a natural ground with a cutter head while propelling the tip conductor, and injects a viscosity imparting liquid into the excavated soil and has plastic fluidity Generate mud, send the mud back through the mud passage formed between the tip conductor body and the support member, take a part of the mud into the sand intake of the tip conductor body and discharge it to the ground. In the pipe propulsion machine that guides the rest to the outer periphery of the buried pipe,
An annular elastic body that can be expanded by enclosing a pressure fluid inside to close the mud passage, or can be shrunk by discharging the pressure fluid to open the mud passage. Provided behind the earth and sand intake so as to surround the outer periphery, Separate from the elastic body, Of this elastic body Part In addition, a mud passage closing device constructed by mounting a shape holding member capable of holding the radial cross section of the elastic body flat against the mud pressure at the time of contraction,
Is achieved.
[0029]
In the pipe propulsion device of the present invention provided with such a mud passage closing device, when starting, the mud passage formed between the outer periphery of the leading conductor body and the cylindrical support member is connected to the earth intake port. It closes by expanding the annular elastic body provided in the back. As a result, the mud generated in the starting process can be taken into the earth and sand intake and discharged to the ground, and mud and groundwater can be prevented from entering a large amount from the rear end opening into the starting shaft through the mud passage. You can also After the leading conductor has passed through the starting shaft of the starting shaft in this way, the rear end opening of the mud passage is isolated from the starting shaft, so the mud passage is opened by contracting the elastic body to perform normal excavation Can do.
[0030]
Of the elastic body Part In particular, since the shape holding member is mounted, the elastic body is always held flat by the shape holding member against the mud pressure when the elastic body is contracted. Therefore, there are no depressions that tend to accumulate foreign matter such as gravel and highly viscous earth and sand, or projections that narrow the mud passage, and the mud flow in the mud passage is not hindered. . In addition, since the elastic body has an annular shape that can be easily brought into close contact with the cylindrical support member, the mud passage can be satisfactorily closed at the time of expansion without being manufactured to have a particularly high followability. There is no difficulty in production. Thus, in the pipe propulsion apparatus of the present invention provided with the mud passage closing device, it is not difficult to manufacture the mud passage closing device, and the attachment of the mud passage does not hinder the flow of mud.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be clarified by describing an embodiment of the present invention with reference to FIGS. 1 to 5.
[0032]
FIG. 1 is a longitudinal sectional view of an essential part of a first example of a pipe propulsion apparatus embodying the present invention, and shows a state when an elastic body is contracted, and FIG. 2 is a pipe propulsion of FIG. FIG. 3 is a view similar to FIG. 1 showing a state when the elastic body is inflated, and FIG. 4 is a view of the elastic body and the shape-retaining member in the pipe propulsion device of FIG. FIG. 5 is a cross-sectional view of a main part of a pipe propulsion device according to a second example embodying the present invention, and shows a state when the elastic body is contracted. It is. In these drawings, the portions denoted by the same reference numerals as those in FIGS. 6 to 10 represent the same portions as those in FIGS. 6 to 10 and will not be described in detail.
[0033]
The tube propulsion units of the first example and the second example described below are both tubular with a cutter head 7 in the front and an embedded tube attached to the rear end, as with the tube propulsion unit according to the prior art. A leading conductor body and a cylindrical support member that is fixed to the outer periphery of the leading conductor body at a distance and supported by a natural ground so as to form a mud passage 6 for passing mud. Has a body. The front conductor body is configured by providing a front inner tube 1, a rear inner tube 2 and a connecting tube 5 for connecting a buried tube having a cutter head 7 in the front, and the support members are the front outer tube 3 and the rear outer tube. This is the same as that of the conventional technique.
[0034]
And while pushing a leading conductor with the main pushing apparatus 10, a cutter head 7 excavates a natural ground, and also injects a viscosity imparting liquid from the cutter head 7 to excavated soil and produces mud with plastic fluidity. Is sent rearward by an annular mud passage 6 formed between the leading conductor main body and the support member, a part of the mud is taken into the earth and sand intake port 8 of the rear inner pipe 2, and the earth discharge pipe is discharged by the earth and sand pump. 9 and discharging the rest to the outer periphery of the buried pipe, the basic structure is the same as the pipe propulsion device according to the prior art. Furthermore, a mud mud passage closing device is attached to the rear of the earth and sand intake 8 as in the prior art.
[0035]
The difference between the pipe propulsion device of the first example and the second example from the tube propulsion device according to the prior art is the structure of the mud passage closing device. Therefore, the mud passage closing devices 30 and 30 'attached to the pipe propulsion device of each example will be described below.
[0036]
First, the first example of the pipe propulsion unit will be described with reference to FIGS. 1 to 4. Reference numeral 30 denotes a mud passage in the first example of the pipe propulsion unit attached to the connecting pipe 5 for closing the mud passage 6. , 31 is a fluid sealing chamber similar to the fluid sealing chamber 21, 32 is a fluid supply / discharge passage using a hose for penetrating a shape holding member 35 (to be described later) and supplying pressure fluid to the fluid sealing chamber 31, and 33 An elastic body attachment member comprising a bolt and a clamping member for attaching the elastic body 34 to the outer peripheral side of the connecting pipe 5, 34 is an annular elastic body similar to the elastic body 24, and 34a is an elastic body similar to the elastic deformation portion 24a 34 is an elastic deformation part, 34b is a fixing part of the elastic body 34 similar to the fixing part 24b, 35 is Separate from the elastic body 34, this Of the elastic deformation part 34a of the elastic body 34 Part This is a shape holding member in the first example of the pipe propulsion device that can be attached to the pipe and can hold the radial cross section of the elastic deformation portion 34a in a flat shape against mud pressure when contracted.
[0037]
The clamping member of the elastic body mounting member 33 is clamped in cooperation with the connecting pipe 5 when the fixing portion 34b of the elastic body 34 is screwed to the connecting pipe 5 with a bolt, like the clamping member of the elastic body mounting member 23. In the example shown here, it also serves to fill an annular recess formed before and after the elastic deformation portion 34a. Therefore, each of the front and rear holding members is formed by dividing a ring-shaped member that matches the annular recess, and when the connecting member 5 is mounted, the outer peripheral surface of the holding member is the rear inner tube 2. The outer peripheral surface and the outer peripheral surface of the fixed portion 5a of the buried pipe in the connecting pipe 5 are substantially aligned with the adjacent portion.
[0038]
The shape holding member 35 in the first example is not substantially deformed even when the mud pressure in the mud passage 6 is applied, and can be deformed so as to be reduced as shown in FIG. It is made of an elastic material. The shape retaining member 35 is formed in an annular shape having a central hole having substantially the same diameter as the outer diameter of the connecting pipe 5 so as to be attached in close contact with the outer periphery of the connecting pipe 5 and has a flat radial cross section. It has a shape. In the shape holding member 35, a fluid supply / drain passage insertion hole 35 a for inserting the fluid supply / discharge passage 32 and introducing the tip opening into the fluid sealing chamber 31 is formed in the radial direction.
[0039]
When attaching such a shape holding member 35 to the connecting pipe 5 together with the elastic body 34, as shown in FIG. 4, after the shape holding member 35 is deformed so as to be reduced, the elastic body 24 is mounted in the elastic body 34. Is attached in the same manner as when attaching to the connecting pipe 5. In the pipe propulsion device of the first example, since the shape holding member 35 is configured by an annular elastic member in this way, the shape holding member 35 can be reduced and deformed and mounted in the elastic body 34, so that the mud passageway can be installed. A closing device can be easily attached. Instead of preparing the shape-retaining member 35, a method in which a convex portion having the same shape as this is provided in advance on the outer peripheral surface of the connecting pipe 5 is also conceivable, but the fixing portion 34b of the elastic body 34 is fixed. Similarly to the portion 24b, it is difficult to elastically deform compared to the elastic deformation portion 34a, so it is difficult to attach the elastic body 34 to the convex portion of the connecting pipe 5.
[0040]
Next, the pipe propulsion device of the second example will be described with reference to FIG. 5. 30 ′ denotes a mud passage in the pipe propulsion device of the second example for closing the mud passage 6 attached to the connecting pipe 5. The closing device 35 'is installed inside the elastic deformation portion 34a of the elastic body 34, and can hold the radial cross section of the elastic deformation portion 34a flat against the mud pressure when contracted. It is a shape maintenance member in a pipe propulsion machine. In FIG. 5, the parts denoted by the same reference numerals as those in FIGS. 1 to 4 represent the same parts as those in these figures.
[0041]
The pipe propulsion unit of the second example is substantially the same as the pipe propulsion unit of the first example except for the structure of the shape retaining member 35 ′ in the mud passage closing device 30 ′. The shape holding member 35 ′ is composed of a plurality of arc-shaped holding member pieces 35′x, 35′y, and 35′z obtained by dividing an annular member like the shape holding member 35 in the first example. It is composed. The shape holding member 35 ′ can be formed of a desired material such as a hard material as long as it does not substantially deform even when the mud pressure in the mud passage 6 is applied. The point is also different from the shape holding member 35.
[0042]
The holding member pieces 35′x, 35′y, and 35′z are sequentially attached to the elastically deforming portion 34a of the elastic body 34 and assembled in an annular shape. A cutout 35′b formed by cutting out in the direction is provided so that only the inner peripheral side can be abutted. Further, one of the holding member pieces 35′x is provided with a fluid supply / discharge path insertion hole 35′a similar to the fluid supply / discharge path insertion hole 35a for inserting the fluid supply / discharge path 32 in the radial direction. Forming.
[0043]
In the pipe propulsion device of the first example and the second example provided with the mud passage closing devices 30, 30 ′, when starting, between the outer periphery of the leading conductor body and the cylindrical support member, The formed mud passage 6 is closed by inflating the elastic deformation portion 34a of the annular elastic body 34 provided behind the earth and sand intake port 8. As a result, the mud produced in the starting process can be taken into the earth and sand intake 8 and discharged to the ground, and mud and groundwater can enter a large amount from the rear end opening into the starting shaft 18 through the mud passage 6. Can also be prevented. After the leading conductor has passed through the starting port of the start shaft 18 in this way, the rear end opening of the mud passage 6 is isolated by the start shaft 18 and the entrance packing 16, so that the mud passage 6 is made to contract by contracting the elastic deformation portion 34 a. It can be opened for normal excavation.
[0044]
Since the shape retaining members 35 and 35 'are particularly mounted inside the elastic deforming portion 34a of the elastic body 34, the elastic deforming portion 34a has a shape retaining member having a radial cross section against mud pressure when contracted. 35 and 35 'are always held flat. Therefore, there is no depression in the elastically deforming portion 34a that is liable to accumulate foreign matter such as gravel or highly viscous earth and sand, or the mud passage 6 is narrowed, and the flow of mud in the mud passage 6 is obstructed. Never happen. In addition, since the elastic deformation portion 34a has an annular shape that can be easily brought into close contact with the cylindrical support member, the mud passage 6 can be satisfactorily closed during expansion without being manufactured to have a particularly high followability. It can be done without difficulty.
[0045]
Thus, in the first and second example pipe propulsion devices provided with the mud passage closing devices 30, 30 ′, it is not difficult to produce the mud passage closing devices 30, 30 ′. The attachment does not impede the flow of mud. As a result, the excavated earth and sand of the face can be smoothly discharged to the ground at a desired speed, and the pipe propulsion method can be carried out efficiently and safely, and the elastic deformation portion 34a can be forcedly deformed by the shape holding members 35, 35. It can be suppressed by 'and the service life of the mud passage closing devices 30, 30' can be extended.
[0046]
In particular, in the pipe propulsion device of the first example, since the shape holding member 35 is configured by an annular elastic member, if the shape holding member 35 is elastically deformed so as to be reduced, it can be mounted in the elastic body 34. The mud passage closing device 30 can be easily attached. In the pipe propulsion device of the second example, since the shape holding member 35 ′ is divided and configured by a plurality of arc-shaped holding member pieces 35′x, 35′y, 35′z, the shape holding member 35 ′ is As in the first example, the elastic body 34 can be mounted without being elastically deformed, and the shape holding member 35 ′ can be formed of a desired material. In any of these examples, in particular, the annular recess formed before and after the elastic deformation portion 34a is filled with the sandwiching member of the elastic body mounting member 33, so there is no risk of foreign matter, earth and sand, etc. accumulating in the recess. .
[0047]
In the example described above, the mud mud passage closing devices 30 and 30 ′ are provided in the connecting pipe 5. However, the closing devices 30 and 30 ′ are mainly configured to remove groundwater and mud in the mud passage 6 when the leading conductor starts. It is only necessary to prevent the mudstone passage 6 from flowing into the start shaft 18 while allowing it to be taken into the earth and sand intake port 8 and discharged to the ground. What is necessary is just to provide. Here, the technical content of the present invention has been described by taking a folding pipe propulsion machine as an example, but by fixing a cylindrical support member so as to form a mud passage 6 on the outer periphery of the tubular leading conductor body. As long as it is a pipe propulsion machine that constitutes the leading conductor and guides the mud with plastic fluidity to the outer circumference of the buried pipe through the mud mud passage 6, the present invention is an ordinary pipe propulsion machine that does not break the leading conductor. It can also be applied to.
[0048]
【The invention's effect】
As is apparent from the above description, the present invention employs the means shown in the section “Means for Solving the Problems”. Therefore, according to the present invention, a cylindrical support member is provided to lead the apparatus. In a pipe propulsion device that constitutes a body and is provided with a mud passage closing device, it is not difficult to manufacture the mud passage closing device, and a pipe propulsion device is obtained in which the mud flow is not obstructed by the attachment. As a result, the pipe propulsion method can be carried out safely, and unreasonable deformation of the elastic deformation portion can be suppressed by the shape holding member, so that the service life of the mud passage closing device can be extended.
[0049]
When the pipe propulsion device of the present invention is embodied, particularly when embodied as in claim 2, the shape holding member is made of an annular elastic member so that the shape holding member is reduced. If it is elastically deformed, it can be installed in the elastic body and a mud passage closing device can be easily attached. According to another aspect of the present invention, the shape holding member is constituted by a plurality of arc-shaped members obtained by dividing the annular member, so that the shape holding member is elastic without being deformed elastically. The shape-retaining member can be formed from a desired material.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a main part of a pipe propulsion device according to a first example embodying the present invention, showing a state when an elastic body is contracted.
2 is a cross-sectional view of a main part of the pipe propulsion device of FIG.
FIG. 3 is a view similar to FIG. 1 showing a state when the elastic body is expanded.
4 is a cross-sectional view for explaining a method of attaching an elastic body and a shape holding member in the pipe propulsion device of FIG.
FIG. 5 is a cross-sectional view of a main part of a pipe propulsion device of a second example embodying the present invention, and is a view showing a state when an elastic body is contracted.
FIG. 6 is a longitudinal sectional view of a main part in a conventional pipe propulsion device when an elastic body is contracted before starting.
7 is a cross-sectional view of a main part of the pipe propulsion device of FIG. 6;
FIG. 8 is a longitudinal sectional view of a main part in a conventional pipe propulsion device when an elastic body is expanded at the time of starting.
FIG. 9 is a longitudinal cross-sectional view of a main part in a conventional pipe propulsion device when an elastic body is contracted after the start is completed.
FIG. 10 is a longitudinal sectional view showing a state in which a conventional pipe propulsion device is started in a start shaft.
[Explanation of symbols]
1 Front inner pipe
2 Rear inner pipe
3 Front outer tube
4 Rear outer pipe
5 Connection pipe
6 Mud passage
7 Cutter head
8 Sediment intake port
9 Drainage pipe
10 original pusher
16 Entrance packing
18 Starting shaft
20, 30, 30 'Mud passage closing device
21, 31 Fluid enclosure
22, 32 Fluid supply / discharge path
23, 33 Elastic body mounting member
24, 34 Elastic body
24a, 34a Elastic deformation part (of elastic bodies 24, 34)
24b, 34b (elastic body 24, 34) fixed part
35,35 'shape retaining member
35'x, 35'y, 35'z holding member piece

Claims (3)

A tubular front conductor body with a cutter head in the front and a buried pipe attached to the rear end, and a ground fixed to the outer periphery of the front conductor body so as to form a mud passage for passing mud. It has a tip conductor composed of a cylindrical support member supported by a mountain, and excavates a natural ground with a cutter head while propelling the tip conductor, and injects a viscosity imparting liquid into the excavated soil and has plastic fluidity Generate mud, send the mud back through the mud passage formed between the tip conductor body and the support member, take a part of the mud into the sand intake of the tip conductor body and discharge it to the ground. In the pipe propulsion machine that guides the rest to the outer periphery of the buried pipe,
An annular elastic body that can be expanded by enclosing a pressure fluid inside to close the mud passage, or can be shrunk by discharging the pressure fluid to open the mud passage. periphery is provided on the rear of the sand inlet so as to surround, separately from the elastic body, the inner portion of the elastic member, a radial cross-section of the elastic body against the mud pressure at the time of contraction to flat A pipe propulsion device provided with a mud passage closing device provided with a shape holding member capable of being held.   2. The pipe propulsion device according to claim 1, wherein the shape holding member is constituted by an annular elastic member. The pipe propulsion device according to claim 1, wherein the shape maintaining member is constituted by a plurality of arc-shaped members obtained by dividing an annular member.

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