JP2001349184A - Tunnel excavator having rectangular section - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tunnel excavator having a rectangular section capable of continuously excavating while preventing the collapse of a face ground, at the same time, also facilitating the directional control and smoothly and efficiently carrying excavated earth and sand out. SOLUTION: The tunnel excavator having the rectangular section is so constituted that excavation means formed by projecting a plurality of arms putting excavation edges on the front ends to a rotational shaft in a state to change directions at right angles to each other every certain interval are successively arranged to the inside of the front end in an opening of a cylindrical body having a rectangular section to continuously excavate the face ground taken inside of the end in the opening of the cylindrical body with the excavation edges by rotation of the rotational shaft, at the same time, an opening bottom section is provided to the lower surface of the cylindrical boy to excavate the ground exposed to the opening bottom section by moving the whole excavation means below and that the excavated earth and sand are pushed backward with the excavation edges to direcly throw down to a belt conveyor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel excavator for excavating a rectangular small-section tunnel in the ground.

[0002]

2. Description of the Related Art Conventionally, for example, when constructing an underground structure which is a passage crossing under a track or a road underground, a shaft is excavated across a track or a road, and a plurality of shafts are excavated between both shafts. After laying a rectangular pipe in parallel at least at the upper floor position of the planned underground structure to form a pipe roof, the front end face of the ready-made underground structure is in contact with the rear end face of the pipe roof from one of the shafts Under such circumstances, the earth and sand inside the underground structure are excavated and eliminated while being propelled, thereby replacing the pipe roof with the underground structure.

At this time, in order to bury a rectangular pipe for forming a pipe roof as described above in the ground, as shown in FIG. A rectangular section tunnel excavator B is pushed in, and a propulsion device C such as a jack having a rear end face of the rectangular pipe P disposed in the shaft A while sequentially connecting the rectangular pipes P following the rectangular section tunnel excavator B. , The tunnel excavator B having a rectangular cross section is excavated, and reaches the other shaft, thereby burying a series of rectangular pipes connected in series between the two shafts. Then, in the same manner, the above-mentioned pipe roof is formed by sequentially embedding and constructing the next group of rectangular pipes adjacent to this group of rectangular pipes.

A tunnel excavator B having a rectangular section for burying the rectangular pipe in the ground while following the rectangular pipe is disclosed in, for example, JP-A-10-26678.
An excavator such as that described in Japanese Patent Publication No. 5 is known. That is, this rectangular cross-section tunnel excavator is capable of vertically reciprocatingly rotating the earth and sand scraping plates D, D, each having a cutting blade at the tip thereof, in the upper and lower portions in the opening front end of the tubular body having a rectangular cross section. Arranged and excavated by a cutting blade, the earth and sand raked into the earth and sand intake space in the opening front end of the cylinder by these earth and sand raking plates D, D, and the earth and sand in the intake space together with muddy water through a suction pipe. It is configured to be carried backward.

[0005]

However, according to the above-described tunnel excavator having a rectangular cross section, the excavation of the front face ground is performed when the upper sediment scraping plate D is turned downward. When the lower sediment scraping plate D is rotated upward, and when the lower sediment scraping plates D, D are rotated in the opposite direction, the ground is not excavated by the cutting blade, and therefore, excavation is performed. There is a problem that the excavation by the machine is intermittent and the work efficiency is reduced. Furthermore, since the tip of the earth and sand raking plates D, D protrudes forward from the opening front end of the excavator, when the front face ground is excavated by the cutting blade attached to the tip, the face ground immediately after the excavation is formed. When excavating a tunnel in a ground with shallow earth cover, it may collapse and collapse, and the ground above it may sink.

Further, when the tunnel is excavated in the shallow earth with the rectangular cross section tunnel excavator, the earth pressure applied to the upper side of the excavator is small and the upper surface of the excavator main body having a rectangular cross section is used. Since the ground on the lower side is usually harder than the lower side, when the tunnel excavator is propelled,
At present, it is difficult to control the direction of the excavation in the upward direction, and the conventional tunnel excavator has not taken sufficient measures. Further, once the earth and sand excavated by the cutting blade is once scraped into the earth and sand intake space in the front end of the opening, the earth and sand in the intake space is transported backward together with mud through the suction pipe, There has been a problem that the entire discharging apparatus becomes complicated and a failure easily occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object thereof is to continuously excavate the front face ground to improve work efficiency and to improve the work efficiency. An object of the present invention is to provide a tunnel excavator having a rectangular cross section capable of performing excavation while always pressing down, further facilitating vertical direction control, and performing smooth and efficient removal of excavated earth and sand.

[0008]

In order to achieve the above object, a rectangular section tunnel excavator according to the present invention has a rectangular section tunnel excavator which excavates by a propulsive force from the rear side. In the front end of the opening of the tubular body having a rectangular cross section, a plurality of arms each having a drilling blade attached to the tip thereof on a rotating shaft orthogonal to the longitudinal direction of the tubular body are provided with the length of the rotating shaft. Digging means projecting in a direction perpendicular to the rotation axis at regular intervals in the direction, a belt conveyor is provided behind the digging means, and soil excavated by the digging means is digged by the digging means. The excavator blade is configured to be fed onto the conveyor start end of the belt conveyor by the rotation of the excavating blade.

In the tunnel excavator having the rectangular cross section constructed as described above, the invention according to claim 2 is directed to an inclined opening end surface in which the opening front end surface of the cylindrical body as the excavator body is inclined obliquely rearward from the upper end to the lower end. And the lower end of the front end of the opening is cut off between both sides to form a bottom of the opening, and the ground exposed at the bottom of the opening is excavated by the excavating means. Furthermore, the invention according to claim 3 is characterized in that the excavating means is disposed at an upper part and a lower part in a front end opening of the cylindrical body, and the lower excavating means is disposed so as to be vertically movable. And

According to a fourth aspect of the present invention, in the plurality of arms constituting the excavating means, a ground excavation portion is provided by an excavation blade attached to a tip of an arm adjacent in the longitudinal direction of the rotating shaft. Are arranged at regular intervals in the longitudinal direction of the rotating shaft so that they are continuous with each other in the width direction. Further, the invention according to claim 5 has a structure in which the excavating means is connected so as to be able to be divided, and the structure in which this divisible excavating means is detachably attached to the opening front end of the cylindrical body. It is characterized by the following.

[0011]

When the rotary shaft of the excavating means provided in the opening front end of the cylindrical body is rotated while the cylindrical body which is the main body of the excavator is propelled by the propulsive force from the rear side, the rotary shaft is rotated. While the plurality of protruding arms are integrally rotated with the rotating shaft in one direction around the axis, the ground in front of the ground is continuously excavated and excavated by the excavating blade attached to the tip thereof. The earth and sand is vigorously pushed backward by the cutting blade when the arm rotates backward, thrown into the conveyor start end of the belt conveyor, dropped, and conveyed backward by the belt conveyor. Therefore, tunnels can be smoothly and efficiently excavated by this rectangular section tunnel excavator, and the earth and sand excavated by the cutting blades is directly fed onto the conveyor start end of the belt conveyor. Not only is it possible to simplify the system and it is difficult for a failure to occur, but also it is possible to carry out the earth and sand smoothly.

Further, since the excavating means is disposed in the front end of the opening of the cylindrical body, the excavating means is excavated in a state in which the face ground is taken into the cylindrical body. There is no danger of the ground breaking down, and the excavation can be performed efficiently while preventing the subsidence of the ground above even in the shallow ground. In addition, the drilling blade attached to the tip of the arm is sequentially turned rearward in the cylinder by the rotation of the rotating shaft, so that maintenance, inspection, and replacement of the drilling blade can be easily performed.

Further, according to the second aspect of the present invention, the opening front end face of the cylindrical body, which is the main body of the excavator, is formed on the inclined opening end face inclined obliquely rearward from the upper end to the lower end. The face can be formed diagonally to prevent collapse, and furthermore, the lower end of the front end of the opening of the cylindrical body is cut off between both sides to form at the bottom of the opening, and the ground exposed at the bottom of the opening Is excavated by the excavation means, so that the excavation resistance on the lower surface at the front end of the opening of the cylindrical body can be suppressed, and the tunnel excavator can be prevented from digging upward.

According to the third aspect of the present invention, since the excavating means is disposed at the upper part and the lower part in the opening at the front end of the cylindrical body, the upper and lower excavating means can be used for the upper half of the face ground. And the lower half can be excavated continuously, and by changing the rotation speed and rotation direction of the arm of each cutting means, the vertical position of the excavator during excavation can be accurately corrected. Can be performed, and furthermore, since the lower excavating means can be moved and adjusted in the vertical direction, by moving the lower excavating means downward, when the tunnel excavator is in the upward excavation state as described above, Excessive excavation of the ground at the bottom of the opening by the cutting blade of the excavating means allows the direction to be corrected reliably and easily.

According to the fourth aspect of the present invention, in the plurality of arms constituting the excavating means, the ground excavation unit is provided with the excavation blade attached to the tip of the arm adjacent in the longitudinal direction of the rotating shaft. Are arranged at regular intervals in the longitudinal direction of the rotating shaft so that they are continuous with each other in the width direction, so that the entire face ground can be excavated uniformly and efficiently, with high accuracy. Tunnel excavation can be performed, and the construction speed can be further improved.

Further, according to the fifth aspect of the invention, the excavating means is structured so as to be dividably connected to one half and the other half, and the divisible excavating means is connected to the opening front end of the cylindrical body. It can be removed from the opening front end of the cylinder while excavating means is divided by the operator, and there are obstacles such as gravel, cobblestone, wood, etc. on the ground to be excavated. In this case, the work of removing the obstacle can be reliably performed by removing the excavation means.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified longitudinal side view of a tunnel excavator having a rectangular cross section, and FIG. A cylindrical body made of a rectangular steel pipe having a rectangular cross section of a predetermined length and an open front and rear end, and an opening front end face of the cylindrical body 1 is formed on an inclined opening end face which is inclined obliquely rearward from an upper end to a lower end. . Specifically, the upper surface of the cylindrical body 1 having a certain width
The front end surfaces of both side surfaces 1b, 1b extending downward at right angles from both side ends of 1a are inclined obliquely rearward from the upper end to the lower end, and the lower ends are formed at both ends of the lower surface 1c forming the bottom wall surface of the cylindrical body 1. It is structured to be connected to Therefore, the upper surface 1a of the cylindrical body 1 has a shape protruding forward by a certain length with respect to the lower surface 1c. The inclined opening end face is formed in the blade port 2.

Further, the lower end of the opening front end of the cylindrical body 1, that is, the lower surface 1c is cut off by a predetermined length from the front end thereof between both side surfaces 1b, 1b, so that the front end surface of the lower surface 1c is cut on both side surfaces.
1b, the lower surface 1c
The opening bottom 3 is formed such that the ground is exposed between the front end surface of the base and the lower end ends of the side surfaces 1b, 1b.

The upper excavating means 4 for excavating the upper half and the lower half of the front ground of the cylindrical body 1 over the entire width of the cylindrical body 1 is provided in the opening front end of the cylindrical body 1 thus formed. And the lower excavation means 5 are arranged at a certain interval vertically. These upper and lower excavating means 4 and 5 are provided with a plurality of arms 7 having excavating blades 8 attached to the ends thereof on rotating shafts 6 and 6 'orthogonal to the longitudinal direction of the cylindrical body. It has a structure in which it protrudes at regular intervals in the length direction and in a direction orthogonal to the rotating shafts 6 and 6 ′.

The structure of the vertical excavating means 4, 5 will be described in more detail. The vertical rotating shafts 6, 6 'are, as shown in FIG. 2 is slightly longer than the length of
Is a half-side excavating means 4 having a plurality of arms 7 having excavating blades 8 attached to the ends directly fixed to the rotating shafts 6 and 6 '.
A and 5A and casings 10 and 10 'rotated by drive motors 9 and 9' (shown in FIGS. 2, 4 and 5) are provided with cutting blades 8 'at their tips on the outer and inner end faces thereof. A plurality of arms 7 'respectively fixed to the other half of the excavating means 4B, 5B, and the rotating shaft 6, which faces the casings 10, 10' of the upper and lower excavating means 4, 5;
The connecting end plates 11, 11 'are fixed to the inner end surface of
The rotating shafts 6 and 6 'and the casings 10 and 10' can be detachably mounted on the same center line on the opposing inner end faces of the casings 10 and 10 'or the arms 7' fixed to the inner end faces by bolts 12. It is connected to.

Each of the arms 7 directly fixed to the rotating shafts 6 and 6 'is composed of two arm portions 7A and 7A protruding from the rotating shaft 6 in opposite directions in the same vertical plane. Further, the arms 7, 7 adjacent to each other in the length direction of the rotating shaft 6 project in a direction perpendicular to each other. Similarly, in each of the arms 7 'fixed to the rotating casings 10, 10', two arms 7B, 7B projecting from the casings 10, 10 'in opposite directions in the same vertical plane. The adjacent arms 7 ', 7' project from each other in a direction perpendicular to each other. That is, as shown in FIG. 2 and FIG.
Arms 7A whose projections 7A project upward and downward from the rotation shafts 6 and 6 ', and arms 7A and 7A whose arms 7A project forward and backward from the rotation shafts 6 and 6' are arranged alternately. The same applies to 10 and 10 ', and the arms 7 and 7' facing the rotating shafts 6 and 6 'and the rotating casings 10 and 10' also protrude perpendicularly to each other.

Furthermore, the tips of these arms 7, 7 '
The excavation blades 8 which are all located at the same radius from the rotation center line and which are mounted on the tips of the arms 7, 7 'all move on a circular locus having the same radius. This excavating blade 8 has two blade bodies 8A having a fixed width and having cutting edges 81 and 82 at the front and rear,
8A is disposed on both sides of the distal ends of the arms 7, 7 ', and is integrally fixed to the distal ends of the arms 7, 7' by bolts 33, and
The width of the digging blade 8 is made equal to the width between the adjacent arms, and the ground digging portion excavated by the digging blade 8 attached to the tip of one arm and the other arm adjacent to this arm A ground excavation part excavated by the excavation blade 8 attached to the tip is in contact with each other or partially overlapped to enable excavation to be continued in the width direction. The blade body 8A has a top surface 83 formed in a V-shaped side surface and front and rear end surfaces formed on a sediment scraping surface 84 inclined from the front and rear cutting edges 81 and 82 toward the center of the rotating shafts 6 and 6 '. Has formed.

The distance between the rotating shaft 6 of the upper excavating means 4 and the rotating shaft 6 'of the lower excavating means 5 is set to a distance slightly smaller than the diameter of the circular locus on which the excavating blade 8 moves. Thus, a part of the ground excavation part by the vertical excavation means 4 and 5 is overlapped to enable excavation continuously in the vertical direction.
In order to enable such excavation, the outer end of the rotating shaft 6 of the upper excavating means 4 is directed to one side of the cylindrical body 1 and the rotating casing 10 is arranged on the other side, while the lower The outer end of the rotating shaft 6 'of the excavating means 4 is directed toward the other side surface of the cylindrical body 1, and the rotating casing 10' is disposed on one side of the excavating means 4.
The arm 7, 7 and the arm 7 ', 7', 7 ', 7' which are vertically opposed to each other and the lower excavation means 5 are configured to be perpendicular to each other.

In addition, the rotating shafts 6 of the vertical excavating means 4 and 5
The vertical excavation means 4 and 5 are connected to the cylindrical body 1 so that the line connecting the centers of 6 ′ is parallel to the inclined front end surfaces of both side surfaces 1b and 1b of the cylindrical body 1.
When the digging blades 8 of these vertical digging means 4 and 5 are viewed from the side, the cutting edge 2 of the cylindrical body 1
Is configured to pass through the position.

In the upper excavating means 4, the mounting structure of the rotary shaft 6 of the excavating means 4A on one half side and the rotary casing 10 of the excavating means 4B on the other half side with respect to the inner surface facing the cylindrical body 1 is shown in FIGS. As shown in FIG. 4, the outer end of the rotating shaft 6 is rotatably supported by a bearing member 13 in the half-side excavating means 4A. It is detachably fixed and supported by bolts 34 on a fixed base plate 14 fixed to the inner surface. The fixed base plate 14 includes a bearing member 13
A shallow bottom receiving groove 14a opened in the front-rear direction is provided on the inner side surface for contacting and receiving the bearing member. The bearing member 13 is fitted into the shallow bottom receiving groove 14a via a thin extraction plate 15 so that the front-rear position can be adjusted. After being combined, it is fixed to the fixed base plate 14 by the bolts 34 described above.

When removing the excavating means 4A on the one half side from the fixed base plate 14, the extraction plate 15 is removed from the shallow bottom receiving groove 14a after removing the bolt 34, and the shallow bottom receiving groove 14a and the bearing are removed. A gap is generated between the excavating means 4A on the one half side and the excavating means 4B on the other half side.
This is provided so that the work of removing the excavating means 4A on one half can be performed smoothly while the bearing member 13 is moved toward the front along the shallow bottom receiving groove 14a.

On the other hand, in the excavating means 4B on the other half side,
The installation base plate 17 for the drive motor 9 of the rotary casing 10 is shown in FIG.
As shown in FIG. 5, a cylindrical base 1 is detachably fixed and supported by bolts 19 to a fixed base plate 18 fixed to the upper inner surface of the other side surface 1b. The fixed base plate 18 is provided with a shallow bottom receiving groove portion 18a opened in the front-rear direction similarly to the fixed base plate 14 of the excavating means 4A on the one half side, and the mounting base plate 17 is provided in the shallow bottom receiving groove portion 18a. After adjusting the position of the bolt 19
Is fixed to the fixed base plate 18.

In the lower excavating means 5 provided below the upper excavating means 4, the rotation shaft 6 ′ of the other half excavating means 5 A with respect to the inner side surface of the cylindrical body 1 facing the inner half of the lower excavating means 5. The mounting structure of the excavating means 5B to the rotary casing 10 'is such that the outer end of the rotating shaft 6' is rotatably supported by the bearing member 20 in the other half-side excavating means 5A.
Is fixed and supported by bolts 22 on a fixed base plate 21 fixed to the lower inner surface of the other side surface 1b of the cylindrical body 1. As shown in FIG. 5, the fixing base plate 21 is provided with a receiving groove portion 21a which is inclined obliquely forward toward the opening bottom 3 of the cylindrical body 1 from the upper end to the lower end so as to penetrate between the upper and lower ends. Yes,
The bearing member 20 is fitted into the receiving groove portion 21a so that the position of the bearing member 20 can be adjusted in the vertical direction, and is fixed to the fixed base plate 21 by the bolts 22 through the vertically long holes 23 provided on the four sides of the bearing member 20.

Further, a support rod 24 is protruded from the other side surface 1b of the cylindrical body 1 above the fixed base plate 21, and the lower end of the screw rod 25 inserted through the support rod 24 is connected to the upper end surface of the bearing member 20. A pair of upper and lower nuts 27, 27 screwed into the screw hole 26 formed in the center and screwed to the upper part of the screw rod 25 are brought into contact with the upper and lower surfaces of the support rod 24, and the lower nut 27 and fixed base plate 21
After loosening the fixing of the bearing member 20 to the upper nut 27
By rotating the bearing, the bearing member 20 is received in the groove 21.
The mounting position of the excavating means 5 is adjusted by vertically sliding along a.

On the other hand, in the excavating means 5B on the half part side,
As shown in FIG. 4, an installation base plate 28 for the drive motor 9 'of the rotary casing 10' is fixed and supported by bolts 30 to a fixed base plate 29 fixed to the lower inner surface of one side surface 1b of the cylindrical body 1. . Similar to the fixed base plate 21 of the excavating means 5A on the other half side, the fixed base plate 29 has a receiving groove inclined obliquely forward toward the opening bottom 3 of the cylindrical body 1 from the upper end to the lower end. The installation base plate 28 is fitted in the receiving groove portion 29a so that the position of the installation base plate 28 can be adjusted in the vertical direction, and a vertically long hole 31 provided in each of four sides of the installation base plate 28 is provided. And is fixed to the fixed base plate 29 by the bolt 30.

Further, a support rod 24 'is protruded from one side surface 1b of the cylindrical body 1 above the fixed base plate 29, and the lower end of the screw rod 25' inserted through the support rod 24 'is connected to the installation base plate. A pair of upper and lower nuts 27 ', 27' screwed into a screw hole 26 'recessed in the center of the upper end surface of 28 and screwed onto the upper part of a screw rod 25'.
Abut on the upper and lower surfaces of the support rod 24 ', and the lower nut
After loosening the fixation of the installation base plate 28 to the fixed base plate 27 'and rotating the upper nut 27', the installation is performed together with the rotation operation of the nut 27 of the other half-side excavating means 5A described above. The base plate 28 is configured to slide up and down along the receiving groove 29a to adjust the mounting position of the upper excavating means 5.

Driving motors 9 and 9 'are provided in the rotary casings 10 and 10' of the upper and lower excavating means 4 and 5, respectively.
28 are installed and fixed respectively. Drive motor 9, 9 '
A rotation transmission member 9b is fixedly attached to the rotation shaft 9a, and these rotation transmission members 9b are attached to the rotation casings 10, 10 '.
And the rotation of the drive motors 9 and 9 'is transmitted to the rotary casings 10 and 10', respectively.
In the figure, 32, 32 ', 33, 33' are hydraulic hoses of the driving motors 9, 9 '.

The cylindrical body 1 behind the lower excavating means 5
A belt conveyor 40 is installed on the lower surface 1c of the belt conveyor with its transport direction facing the front-rear direction of the cylindrical body 1, and the transport start portion of the belt conveyor 40 is brought close to the lower rear part of the lower excavation means 5. It is arranged in. The upper surface of the transfer start end of the belt conveyor 40 is located at a position lower than the center of the rotating shaft 6 ′ of the lower excavating means 5, and the excavated earth and sand which is pushed backward by the excavating blade 8 of the lower excavating means 5 is conveyed. It is configured to drop directly on the start end. In addition, this belt conveyor
40 is gradually inclined upward from the transport start end toward the transport end, and the transport start end of the next belt conveyor is similarly placed from the transport start end to the transport end below the transport end. The belt conveyor is installed in such a state that it is gradually inclined upward, and the installation state of such a belt conveyor is sequentially performed up to the start end of tunnel excavation, so that the excavated earth and sand is carried out rearward.

Between the transfer start end of the belt conveyor 40 and the lower excavation means 5, the upper end of the opening bottom 3 of the tubular body 1 as the excavator body, that is, from the front end edge of the lower surface 1 c. As shown in FIG. 6, a lower edge of the belt conveyor 40 is fixed on both sides of the belt conveyor 40. Side surfaces 1b, 1b of the cylindrical body 1 are positioned in proximity to both side edges of the top surface of
The two sloped plates 42, 42 which are respectively inclined upwardly toward the lower opposing inner surface are disposed, and the front ends of these sloped plates 42, 42 are further inclined downward from the upper end to the lower end. The front inclined plates 44, 44 are formed on the front inclined plates 44, 44, and the lower edges of the front inclined plates 44, 44 are fixed to the front inclined plates.
41 are integrally connected to both side edges.

The inclined plates 42 on both sides need not necessarily be provided along both side edges of the belt conveyor 40 over the entire length of the belt conveyor 40, and are pushed backward by the vertical excavation means 4, 5. It may be formed in a length corresponding to the maximum flight distance of excavated earth and sand. This side inclined plate 42,
Reference numeral 42 denotes a structure in which the lower surface is installed on both sides of the lower surface 1c of the cylindrical body 1 by a suitable supporting leg member (not shown).

The tunnel excavator having the rectangular cross section configured as described above is used for embedding a rectangular pipe P in the ground like the tunnel excavator shown in FIG. That is, this rectangular section tunnel excavator is made to enter the ground where the rectangular pipe P is to be buried from one of the shafts A, and the rear end face of the rectangular pipe P is successively connected to the rectangular pipe P following the tunnel excavator. A plurality of jacks or the like which are pushed in by a propulsion device C such as a jack disposed in the shaft A and which follow in series while excavating the cutting face ground by the upper and lower excavating means 4 and 5 in the cylindrical body 1 of this rectangular section tunnel excavator. The rectangular pipe P is buried underground.

The mode of excavation of the rectangular section tunnel for embedding the rectangular pipe P by this rectangular section tunnel excavator will be described. The drive motors 9, 9 'of the vertical excavation means 4, 5 will be described.
Is operated, the vertically rotating casings 10, 10 'of the vertically excavating means 4, 5 rotate to rotate these rotating casings 10, 10'.
The upper and lower rotating shafts 6 and 6 'directly connected to the rotating shafts 10' respectively rotate, and the excavating blades 8 of the plurality of arms 7 and 7 'projecting at right angles from these rotating shafts 6 and 6' are connected to the arms. Rotational movement is performed at high speed so as to draw a circle on the rotation trajectory 7, 7 ', and the excavating blade 8 excavates the front face ground while the cylindrical body 1 is propelled by the propulsive force from the rear side.

As shown in FIG. 1, the rotational movement direction of the excavating blade 8 of the upper excavating means 4 is a counterclockwise direction when viewed from the other side, that is, the excavating blade 8 moves from the upper side to the front side, and 1
Is a direction in which it moves backward while excavating the face ground facing the upper half of the open end of the excavator. Therefore, part of the excavated earth and sand falls to the front part side of the lower excavation means 5 and the rest is excavated blade 8.
While being sent rearward by the earth and sand raising surface 84, the excavating blade 8 is pushed backward by centrifugal force due to the high-speed rotation of the excavating blade 8, dropped on the conveyance start end of the belt conveyor 40, and carried out rearward.

On the other hand, the direction of rotation of the digging blade 8 of the lower digging means 5 is opposite to that of the digging blade 8 of the upper digging means 4, that is, the digging blade 8 moves forward from below to move the cylindrical body 1 forward. This is a direction in which the excavated soil is moved backward while excavating the face ground facing the lower half of the open end. It is pushed backward by centrifugal force due to the high-speed rotation of the excavating blade 8, and is thrown onto the transport start end of the belt conveyor 40 to be transported backward.

The upper and lower excavating means 4 and 5 have upper and lower halves of the cylindrical body 1 provided with respective rotating shafts 6 and 6 'and arms 7, 7' projecting from the rotating casings 10, 10 '. As described above, the arrangement state of the excavating blades 8 provided at regular intervals in the width direction and attached to the distal ends of these arms 7 and 7 ′ is adjacent to each other in the left-right direction and the up-down direction. Drilling blade 8,
Since the excavation part by 8 is arranged so as to be continuous,
The entire surface of the face ground can be excavated without leaving any undigged portion in the face ground corresponding to the opening front end of the cylindrical body 1.

Further, the earth and sand excavated by the excavation blades 8 attached to the arms 7, 7 'on both sides of the upper and lower excavation means 4, 5 are blown onto both sides of the belt conveyor 40. On both sides of the conveyor 40, inclined plates 42, 42 which are inclined downward from the lower inner surface of the cylindrical body 1 to both side edges of the upper surface of the conveyor of the belt conveyor 40, are installed. The excavated earth and sand falls onto the pits 42, 42 and slides on the inclined surfaces of the sloping plates 42, 42 and is transferred onto the belt conveyor 40. Further, the excavated earth and sand that has fallen to the front side of the belt conveyor 40 is received on the earth and sand guide front inclined plate 41, slides down the inclined surface to the opening bottom 3 of the cylindrical body 1, and again the lower excavating means. 4 digging blades 8
, And is dropped onto the belt conveyor 40. The upper and lower excavating means 4 and 5 can similarly push the excavated earth and sand backward by the excavating blade 8 even if the rotation direction is opposite to the above, and drop the excavated earth onto the transport start end of the belt conveyor 40. .

In the vertical excavating means 4 and 5, the excavating blade 8 for excavating the face ground does not protrude forward from the opening front end face of the cylindrical body 1, that is, the cutting edge 2, and the cylindrical body 1
When the cylindrical body 1 is propelled by the propulsive force from the rear, since the excavating blade 8 is configured to rotate in the inside,
The cutting ground is excavated in the tubular body 1 while being taken into the opening front end of the tubular body 1 by the cutting edge 2. Therefore, the ground in front of the tubular body 1 is not likely to collapse. It is possible to efficiently excavate a tunnel with a rectangular cross section while continuously excavating earth and sand taken into the part by the vertical excavation means 4 and 5.

Further, the above-described tunnel excavator having a rectangular cross section has:
Since the upper surface 1a of the cylindrical body 1 is projected forward from the lower surface 1c and the front end surface of the opening is formed as an inclined opening end surface which is inclined obliquely rearward from the upper end to the lower end, the face face is formed obliquely. When the excavator is directed in the upward excavation direction while excavating smoothly while stably supporting the upper ground, the lower excavation means 4 is moved downward to expose the excavation bottom 3 of the cylindrical body 1. If the existing ground is excavated by the excavation means 4, the direction can be corrected downward easily and accurately.

In order to adjust the position of the lower excavating means 4 in the vertical direction, the bearing member 20 of the rotating shaft 6 'and the installation base plate 28 of the driving motor 9' of the rotating casing 10 'are mounted on the inner surfaces of the cylindrical body 1 on both sides facing each other. After loosening the bolts 22 and 31 to the fixed base plates 21 and 29 fixed to the support member 24, the bearing members 20 and the installation base plate 28 were inserted into the support rods 24 and 24 'which support the installation base plate 28 in a suspended state. Screw rod 2
It can be easily performed by vertically moving 5, 25 'by rotating the nuts 27, 27'.

During excavation, if there are obstacles such as gravel, boulders, and wood in the ground to be excavated,
After removing the belt conveyor 40, the worker enters the cylindrical body 1, removes the upper excavating means 4, and provides a work space at the front end of the opening of the cylindrical body 1 to perform the work of removing the obstacle. The removal work of the upper excavation means 4 firstly includes
Bearing member of rotary shaft 6 in excavating means 4A on one half side
After removing the bolts 34 fixing the 13 to the fixed base plate 14 on one side surface 1b of the cylindrical body 1, the extraction plate 15 interposed between the bearing member 13 and the fixed base plate 14 is removed. A gap is provided between the bearing member 13 and the fixed base plate 14. Thereafter, the connecting end plate 11 fixed to the inner end face of the rotating shaft 6 is connected to the other half of the excavating means.
The connection is released by removing the bolts 12 from the rotary casing 10 of the 4B, and the excavating means 4A on the one half side is connected to the cylindrical body 1 while moving the bearing member 13 rearward along the shallow receiving groove 14a of the fixed base plate 14. Remove it backwards. Then, the excavating means 4B on the other half side is removed by removing the drive motor installation base plate 17 from the fixed base plate 18 fixed to the other side surface 1b of the cylindrical body 1.

The lower excavating means 5 may be configured to be removable similarly to the upper excavating means 4, but it is necessary only for the upper excavating means 4 to be removed to remove obstacles. It is not always necessary to remove it because it provides a comfortable working space. Further, in the present invention, without arranging the vertical excavating means 4 and 5 as the excavating means,
One large-diameter excavating means having the same structure as these excavating means may be provided in the opening front end of the cylindrical body 1. Further, in the present invention, the rotational movement direction of the excavating blades 8 of the excavating means 4 and 5 is not limited to the direction shown in FIG. 1 described above, and may be a reverse direction. It can be changed.

[Brief description of the drawings]

FIG. 1 is a simplified longitudinal side view of a rectangular section tunnel excavator,

FIG. 2 is a simplified cross-sectional view thereof,

FIG. 3 is a front view in which a part is sectioned,

FIG. 4 is a longitudinal sectional side view partially cut away,

FIG. 5 is a vertical cross-sectional side view of a part of the second embodiment;

FIG. 6 is a simplified perspective view showing an arrangement state of an earth and sand guide inclined plate,

FIG. 7 is a simplified vertical side view for explaining a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical body 3 Opening bottom 4 Upper excavation means 5 Lower excavation means 6, 6 'Rotating shaft 7, 7' Arm 8 Excavating blade 9, 9 'Drive motor 10, 10' Rotating casing

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hidekazu Tanaka 2-2-2 Matsuzakicho, Abeno-ku, Osaka-shi F-term (reference) 2D054 AA02 AC18 BA03 DA02

Claims (5)

[Claims] 1. A tunnel excavator having a rectangular cross section, which excavates by a propulsive force from a rear side, wherein a rotating shaft orthogonal to the longitudinal direction of the cylindrical body is provided in a front end of an opening of the cylindrical body having a rectangular cross section. And a digging means comprising a plurality of arms projecting in a direction perpendicular to the rotation axis at regular intervals in a length direction on the shaft and having a digging blade mounted on a tip thereof. A belt conveyor is arranged behind the digging means, and the earth and sand excavated by the excavating means are configured to be fed onto the conveyor start end of the belt conveyor by rotation of the excavating blade of the excavating means. Rectangular section tunnel excavator. 2. An opening front end surface of a cylindrical body is formed on an inclined opening end surface which is inclined obliquely rearward from an upper end to a lower end, and a lower end portion of the opening front end portion is cut off between both side portions to obtain an opening bottom portion. 2. The tunnel excavator according to claim 1, wherein the excavation means excavates the ground exposed at the bottom of the opening. 3. The excavating means is disposed at an upper part and a lower part in a front end opening of a cylindrical body, and the lower excavating means is disposed so as to be movable in a vertical direction. The rectangular section tunnel excavator according to claim 2. 4. The plurality of arms constituting the excavating means are arranged such that a ground excavation portion by an excavating blade attached to the tip of an arm adjacent to the rotating shaft in the longitudinal direction is continuous with each other in the width direction. The rectangular section tunnel excavator according to claim 1, wherein the tunnel excavator is disposed in a tunnel. 5. The rectangular cross section according to claim 1, wherein the excavating means is connected so as to be able to be divided and is detachably attached to the cylindrical body. Tunnel excavator.