Underground propulsion system and installation method using the same

Abstract

In conventional propulsion systems S, operation is not easy, resulting in significant physical and mental strain on operators. Furthermore, if the propulsion system S deviates significantly from the planned straight line, it can lead to a large loss of thrust and even breakage. [Solution] In this invention, the thrust head 2 is controlled to minimize the thrust position deviation angle Θ formed by the thrust plan line PP and the thrust head thrust position deviation line EL. This allows the thrust head 2 to be automatically thrust, reducing the physical and mental burden on the worker and facilitating the operation of the underground thrusting body. Furthermore, since the thrust head 2 is changed direction gradually, a large load on the thrust head 2 and other components is not placed on it, preventing a large loss of thrust and thus preventing breakage of the thrust head 2 and other components.

Description

Technical Field

[0001] The present invention relates to an underground propulsion body used for forming an underground hole for laying a water pipe or the like underground, in which a plurality of underground propulsion pipes are connected behind a propulsion head that propels underground while rotating around the longitudinal axis of the tip, and a laying method using the same.

Background Art

[0002] Conventionally, an underground propulsion body has been known that is used for forming an underground hole for laying a water pipe or the like underground, in which a plurality of underground propulsion pipes are connected behind a propulsion head that propels underground while rotating around the longitudinal axis of the tip. As this type of propulsion body S (underground propulsion body), a propulsion main body 103 is provided, which is composed of a propulsion head 101 having a substantially cylindrical outer surface and a plurality of propulsion pipes 102 connected behind the propulsion head 101. The propulsion head 101 and each propulsion pipe 102 are connected by a non-flexible connecting portion R2 (see FIG. 12). And, a pressure receiving surface portion E inclined with respect to the head axis P is formed at the tip of the propulsion head 101, and a bending connecting portion R1 is provided at the middle portion of the propulsion head 101 and the middle portion of the propulsion pipe 102 so as to be bendable around a horizontal axis X along the radial direction of the propulsion main body 103. Then, by the operation of an operator, the propulsion head 101 propels, and when the pressure receiving surface E at the tip of the propulsion head 101 receives the earth pressure, the propulsion head 101 and the propulsion pipe 102 are bent with the bending connecting portion R1 as a base point, and the propulsion head 101 and the propulsion pipe 102 are propelled in a direction opposite to the direction in which the pressure receiving surface E faces (for example, Patent Document 1). Here, FIG. 12 is a plan view of a conventional propulsion body.

[0003]

Patent Document 1

Disclosure of the Invention

Problems to be Solved by the Invention

[0004] However, since the propulsion unit S is propelled by the operator rotating the tip of the propulsion unit S, the direction in which the pressure-receiving surface E at the tip of the propulsion head 101 faces is sequentially changed from one direction to the opposite direction and back to the opposite direction. Therefore, the operation of the propulsion unit S is not easy, resulting in a significant physical and mental burden on the operator, which increases operator fatigue. In addition, since the propulsion unit S is propelled by the operator sequentially changing the direction in which the pressure-receiving surface E at the tip of the propulsion head 101 faces is sequentially changed from one direction to the opposite direction and back to the opposite direction, practice is required to propel the propulsion unit S accurately in a straight line. If the operation is performed by an operator who is not very familiar with the operation of the propulsion unit S, the propulsion unit S may deviate significantly from the planned straight line. In such cases, if the propulsion system S is propelled with a large deviation from the planned propulsion line, the operator may rapidly rotate the propulsion head 101 at the tip of the propulsion system 5 to correct the large deviation from the planned propulsion line, thereby rapidly changing the direction of propulsion of the propulsion system S. However, rapidly changing the direction of propulsion of the propulsion system S in this way places a large load on the propulsion system S (propulsion head 101 and propulsion pipe 102), resulting in a large loss of propulsion thrust and also the problem of the propulsion system S (propulsion head 101 and propulsion pipe 102) breaking.

[0005] The present invention has been made in view of the above problems, and aims to provide an underground propulsion system and a method of laying the same that reduces the degree of physical and mental burden on workers when operating the underground propulsion system, thereby reducing worker fatigue, and that prevents large losses of propulsion thrust due to large loads on the propulsion head and other parts, and prevents breakage of the propulsion head and other parts. [Means for solving the problem]

[0006] To solve the above problems and achieve the above objective, the first aspect of the present invention relates to a ground thrusting body used to form underground holes for laying water pipes, etc., in which a plurality of underground thrusting pipes are connected to the rear of a thrusting head whose tip rotates around a longitudinal axis as it propels itself underground, the thrusting body having a pressure-receiving surface formed at its tip that is inclined with respect to the longitudinal axis, and the thrusting head propels itself in the direction of the inclination of the pressure-receiving surface as it receives earth pressure as it propels itself, a plurality of underground thrusting pipes are connected to the rear of the thrusting head via thrusting pipe connecting means, and each has a plurality of bendable connecting parts provided in the longitudinal direction that can be bent in a substantially vertical longitudinal direction, a thrusting plan straight line input setting means into which a thrusting plan straight line, which is the thrusting plan route from the thrusting start point of the thrusting head to the thrusting destination setting point, is input and set, and a thrusting head thrusting position deviation angle calculation storage means into which the thrusting plan straight line and the thrusting head thrusting position deviation straight line connecting the current position of the thrusting head and the thrusting destination setting point are calculated and stored, The system includes a control means that controls the propulsion head so that the propulsion position deviation angle calculated by the propulsion head propulsion position deviation angle calculation and storage means becomes small, and propulsion control is performed so that the propulsion head moves toward the propulsion destination setting point. Because the system controls the propulsion head so that the propulsion position deviation angle formed by the propulsion plan line and the propulsion head propulsion position deviation line becomes small, the propulsion head is automatically propelled to the propulsion destination setting point without the operator having to rotate the propulsion head. This reduces the physical and mental burden on the operator from operating the underground propulsion system, thereby reducing operator fatigue. Furthermore, because it can be operated automatically, even operators who are not accustomed to operating the propulsion head can easily perform the operation. In addition, by eliminating large changes in direction of the propulsion head and underground propulsion pipe, it is possible to prevent large loads from being placed on the propulsion head and underground propulsion pipe, thereby reducing underground propulsion loss and preventing breakage of the propulsion head and underground propulsion pipe.

[0007] According to the present invention, the thrust head's thrust position deviation angle, which is formed by the thrust plan line and the thrust head thrust position deviation line connecting the current position of the thrust head and the thrust destination setting point, is controlled to be small, and the thrust head is controlled to move toward the thrust destination setting point. As a result, the thrust head can be automatically thrust without the operator having to rotate the thrust head, reducing the physical and mental burden on the operator from operating the underground thrusting body and reducing operator fatigue. Furthermore, since the underground thrusting body can be operated automatically, even operators who are not accustomed to operating the thrust head can easily operate the underground thrusting body. In addition, since the thrust position deviation angle of the thrust head becomes smaller at positions farther from the thrust destination setting point, the thrust head's thrust position deviation from the thrust plan line can be corrected by gradually changing the direction of the thrust head. In this way, by utilizing the distance between the propulsion position of the propulsion head and the target propulsion point, deviations in the propulsion position of the propulsion head from the planned propulsion line can be corrected without abrupt changes in the direction of the propulsion head. Furthermore, since deviations in the propulsion position of the propulsion head from the planned propulsion line mainly occur at a distance from the target propulsion point, it is possible to avoid large losses of propulsion thrust due to large loads on the propulsion head and other components throughout the entire region from the propulsion start point to the target propulsion point, thereby preventing breakage of the propulsion head and other components.

[0008] A second aspect of the present invention relates to a ground thrusting body according to the first aspect, wherein the thrusting head thrusting position deviation angle calculation and storage means includes a thrusting head current position deviation length measuring unit that measures the thrusting head current position deviation X-axis length, which is the length from the current position of the thrusting head during thrusting to the thrusting plan line, to the thrusting head current plan point, which is the intersection of a perpendicular line drawn from the thrusting head current position to the thrusting plan line, and the thrusting head current position deviation Y-axis length, which is the length from the thrusting head current plan point to the thrusting destination setting point, and the thrusting head current position deviation X-axis length measured by the thrusting head current position deviation length measuring unit The invention is characterized by comprising: a propulsion head position displacement length storage unit that stores the length and the Y-axis length of the propulsion head's current position displacement; a propulsion head propulsion position displacement angle calculation unit that calculates the propulsion position displacement angle Θ of the propulsion head by Θ = atan(X / Y), where X is the X-axis length of the propulsion head's current position displacement stored in the propulsion head position displacement length storage unit and Y is the Y-axis length of the propulsion head's current position displacement; and a propulsion head propulsion position displacement angle storage unit that stores the propulsion position displacement angle Θ of the propulsion head calculated by the propulsion head propulsion position displacement angle calculation unit.

[0009] According to the present invention, the thrust position displacement angle Θ of the thrust head can be easily calculated by Θ = atan(X / Y), where X is the length in the X-axis direction of the current position of the thrust head and Y is the length in the Y-axis direction of the thrust head's displacement.

[0010] A third aspect of the present invention relates to a ground-penetrating propulsion system according to the second aspect, characterized in that the control means controls the propulsion position displacement angle of the propulsion head to decrease when the propulsion position displacement angle of the propulsion head exceeds a predetermined angle.

[0011] According to the present invention, when the propulsion position displacement angle of the propulsion head exceeds a predetermined angle, the propulsion position displacement angle of the propulsion head is controlled to decrease, thereby enabling stable control of the propulsion direction of the propulsion head.

[0012] A fourth aspect of the present invention relates to a ground-penetrating propulsion system according to the third aspect, characterized in that a predetermined angle Θ1 can be determined by Θ1 = atan(20 / Y).

[0013] According to the present invention, when the X-axis length of the current position displacement of the propulsion head becomes 20 cm or more, the propulsion position displacement angle of the propulsion head is controlled to decrease, thereby enabling stable control of the propulsion direction of the propulsion head.

[0014] A fifth aspect of the present invention relates to a method of laying an underground jacking body according to the second aspect, comprising: a jacking plan straight line setting step in which a jacking plan straight line, which is a jacking plan route from the jacking start point of the jacking head to the jacking destination setting point, is input and set; an underground jacking pipe underground pushing step in which a plurality of underground jacking pipes behind the jacking head are sequentially pushed into the ground from the tip; a jacking head rotation step in which the tip of the jacking head connected to the tip of the underground jacking pipe pushed in by the underground jacking pipe underground pushing step is rotated around the longitudinal axis; and the current position of the jacking head that is jacking underground is The process includes a current position detection step for the thrust head, a thrust head position deviation correction control step which controls the thrust head to reduce the angle of deviation between the thrust plan line connecting the thrust plan line connecting the thrust start point and the thrust destination point and the thrust head position deviation line connecting the current position of the thrust head and the thrust destination point, if the current position of the thrust head detected by the current position detection step is deviating from the thrust plan line connecting the thrust start point and the thrust destination point of the thrust head, and the thrust head rotation step which rotates the tip of the thrust head to propel it. The system includes a propulsion head coupling connection step in which, after the propulsion head reaches the ground surface of the target destination while changing the direction of propulsion of the head, the tip of the propulsion head protruding from the ground surface is connected to the end of the propulsion head coupling by a coupling means, and a supply pipe underground pull-in step in which the propulsion head coupling connected to the propulsion head in the propulsion head coupling connection step, together with multiple underground propulsion pipes, is pulled in the opposite direction to the direction of propulsion from which it was pushed in by the underground propulsion pipe underground pushing step. The propulsion head propulsion position deviation correction control step controls the propulsion head so that the propulsion position deviation angle of the propulsion head formed by the propulsion plan line connecting the propulsion start point and the target destination and the propulsion head propulsion position deviation line connecting the current position of the propulsion head and the target destination is reduced. As a result, the propulsion head is automatically propelled to the target destination without the operator having to rotate the propulsion head, thereby reducing the degree of physical and mental burden on the operator and reducing operator fatigue. Furthermore, because it can be operated automatically, even operators who are not familiar with operating the propulsion head can easily perform the operation.This system eliminates large changes in direction of the jacking head and underground jacking pipe, thereby reducing the load on the jacking head and underground jacking pipe, minimizing underground jacking losses, and preventing breakage of the jacking head and underground jacking pipe.

[0015] According to the present invention, the propulsion head propulsion position deviation correction control process controls the propulsion head so that when the current position of the propulsion head deviates from the propulsion plan line connecting the propulsion start point and the propulsion destination setting point, the propulsion head propulsion position deviation angle formed by the propulsion plan line connecting the propulsion start point and the propulsion destination setting point and the propulsion head propulsion position deviation line connecting the current position of the propulsion head and the propulsion destination setting point is reduced. As a result, the propulsion head can be propelled automatically without the operator having to rotate the propulsion head, reducing the physical and mental burden on the operator from operating the underground propulsion body and reducing operator fatigue. Furthermore, since the underground propulsion body can be operated automatically, even operators who are not accustomed to operating the propulsion head can easily operate the underground propulsion body. In addition, since the propulsion head propulsion position deviation angle becomes smaller at positions farther from the propulsion destination setting point, the propulsion head's propulsion position deviation from the propulsion plan line can be corrected by gradually changing the direction of the propulsion head as it moves further away from the setting point. In this way, by utilizing the distance between the propulsion position of the propulsion head and the target propulsion point, deviations in the propulsion position of the propulsion head from the planned propulsion line can be corrected without abrupt changes in the direction of the propulsion head. Furthermore, since deviations in the propulsion position of the propulsion head from the planned propulsion line mainly occur at a distance from the target propulsion point, it is possible to avoid large losses of propulsion thrust due to large loads on the propulsion head and other components throughout the entire region from the propulsion start point to the target propulsion point, thereby preventing breakage of the propulsion head and other components. [Effects of the Invention]

[0016] According to the present invention, the degree of physical and mental burden on the operator due to the operation of the underground propulsion body is reduced, reducing the fatigue of the operator. At the same time, no significant loss of propulsion thrust occurs due to a large load on the propulsion head or the like, and the propulsion head or the like can be prevented from being damaged.

Brief Description of the Drawings

[0017] [Figure 1] (a) It is a schematic view showing the construction situation of the underground propulsion body in one embodiment of the present invention. (b) It is a view showing that the propulsion head at the tip of the underground propulsion body and the tip of the sheath pipe are connected by an O-shaped fitting. <� [Figure 2] It is a view showing the rotation situation of the conductor at the tip of the propulsion head of the underground propulsion body. [Figure 3] (a) It is a partial cross-sectional view of the propulsion head of the underground propulsion body. (b) It is an exploded view of the connection of the propulsion head of the underground propulsion body. [Figure 4] (a) It is a plan view of the underground propulsion body. (b) It is a front view of the underground propulsion body. [Figure 5] (a) It is an enlarged cross-sectional view C-C between A-A in FIG. 4(b). (b) It is a cross-sectional view D-D in FIG. 5(a). (c) It is an enlarged cross-sectional view C-C between B-B in FIG. 4(b). [Figure 6] It is an exploded view of the connection of the non-bending connection part of the underground propulsion body in one embodiment of the present invention. [Figure 7] It is an explanatory view of the bending action of the bending connection part of the underground propulsion body. [Figure 8] It is a view showing the induction antenna used for the underground propulsion body. [Figure 9] It is a view showing the operation surface of the operation box for operating the underground propulsion body. [Figure 10] It is a reference view for calculating the deviation angle of the propulsion position of the propulsion head of the underground propulsion body. [Figure 11] It is a flowchart of the laying method using the underground propulsion body. [Figure 12] It is a side view showing the propulsion situation of the conventional underground propulsion body.

Best Mode for Carrying Out the Invention

[0018] The underground propelling body in one embodiment of the present invention will be described with reference to the drawings. Here, Fig. 1(a) is a schematic view showing the construction status of the underground propelling body in one embodiment of the present invention, and Fig. 1(b) is a view showing that the propulsion head at the tip of the underground propelling body and the tip of the sheath pipe in one embodiment of the present invention are connected by an O-shaped fitting.

[0019] The underground propulsion unit 1 (underground propulsion device) is used to form underground holes for laying water pipes, etc., by connecting multiple underground propulsion pipes (first underground propulsion pipe 3, second underground propulsion pipe 4, and third and subsequent underground propulsion pipes 5) to the rear of a propulsion head 2 whose tip rotates around its longitudinal axis as it propels itself underground. Specifically, as shown in Figure 1(a), the underground propulsion unit 1 has the first underground propulsion pipe 3 connected to the rear of the propulsion head 2, and then multiple underground propulsion pipes (2, 3, 4) connected in the order of second underground propulsion pipe 4 and third and subsequent underground propulsion pipes 5 to the rear of the first underground propulsion pipe 3. As will be described later, the first underground propulsion pipe 3, second underground propulsion pipe 4, and third and subsequent underground propulsion pipes 5 connected to the rear of the propulsion head 2 are sequentially pushed in from the front by a propulsion device 6 located in a pit 16 formed at the propulsion start point ST, allowing the propulsion head 2 to reach the ground surface at the propulsion destination setting point AR. A hole (not shown) is dug in advance on the ground surface at the designated launch point AR as a marker for the launch point. After the launch head 2 reaches the ground surface at the designated launch point AR, the tip of the launch head 2 protruding from the ground surface is connected to the end of the conduit pipe 19 by an O-shaped fitting 24, as will be described later (see Figure 1(b)). A pipe 25 is inserted inside the conduit pipe 19. The underground thrusting body 1 also has a launching plan linear input setting means, a launching head launching position deviation angle calculation storage means (storage memory), and control means, as will be described later, and the launching of the launch head 2 is controlled by these. The launching plan linear input setting means is provided in the operation box 20, and the launching head launching position deviation angle calculation storage means (storage memory, etc.) and control means are built into the operation box 20.In this embodiment, the propulsion plan linear input setting means is provided in the operation box 20, and the propulsion head propulsion position deviation angle calculation storage means (storage memory, etc.) and control means are built into the operation box 20. However, this is not limited to this configuration, and these may be provided elsewhere. For example, the propulsion head propulsion position deviation angle calculation storage means (storage memory) and control means may be provided in an external computer, and the external computer and the operation box 20 may transmit and receive signals wirelessly or via wired connection to control the propulsion head 2, etc.

[0020] Next, an underground thruster in one embodiment of the present invention will be described with reference to Figures 2 to 8. Here, Figure 2 is a diagram showing the rotation of the leading conductor at the tip of the thrust head of the underground thruster, Figure 3(a) is a partial cross-sectional view of the thrust head of the underground thruster, Figure 3(b) is a coupling division diagram of the thrust head of the underground thruster, Figure 4(a) is a plan view of the underground thruster, Figure 4(b) is a front view of the underground thruster, Figure 5(a) is an enlarged cross-sectional view of CC between A and A in Figure 4(b), Figure 5(b) is a cross-sectional view of D and C in Figure 5(a), Figure 5(c) is an enlarged cross-sectional view of CC between B and C in Figure 4(b), Figure 6 is a coupling division diagram of the non-bent connection part of the underground thruster in one embodiment of the present invention, Figure 7 is an explanatory diagram of the bending action of the bent connection part of the underground thruster, and Figure 8 is a diagram showing the guidance antenna used in the underground thruster.

[0021] The propulsion head 2 has a pressure-receiving surface 8a formed at its tip, which is inclined with respect to the longitudinal axis. As the propulsion head 2 is pushed forward, the pressure-receiving surface 8a receives earth pressure, causing it to be propelled in the direction of the inclination of the pressure-receiving surface 8a. Specifically, the propulsion head 2 consists of a cylindrical propulsion head body 7 and a leading conductor 8 rotatably attached to the tip of the propulsion head body 7. The leading conductor 8 has a pressure-receiving surface 8a formed at its tip, which is inclined with respect to the longitudinal axis (see Figure 2). Inside the propulsion head body 7, a hydraulic rotating device M is provided to provide rotational driving force to the leading conductor 8. When the leading conductor 8 is rotated by the hydraulic rotating device M underground, the pressure-receiving surface 8a formed on the leading conductor 8 also rotates. As the pressure-receiving surface 8a at the tip of the leading conductor 8, which is pushed forward by the propulsion device 6, receives earth pressure as the propulsion head 2 is pushed forward in the direction of the inclination of the pressure-receiving surface 8a, allowing the propulsion direction to be flexibly changed (see Figure 1). Here, the rotation of the leading conductor 8 of the propulsion head 2 can also be performed by the operation unit 23 of the operation box 20, which will be described later and operated on the ground (see Figures 1 and 9). In other words, the underground propulsion body 1 automatically rotates the leading conductor 8 of the propulsion head 2, but if the propulsion head 2 collides with a rock or the like, the leading conductor 8 of the propulsion head 2 can also be manually rotated using the operation unit 23 of the operation box 20. In this embodiment, the leading conductor 8 is rotated around its longitudinal axis by a hydraulic rotating device M provided inside the propulsion head body 7, but it is not limited to this, and the leading conductor 8 may be rotated around its longitudinal axis by a driving means such as pneumatic or electric. Also, in this embodiment, the propulsion head body 7 of the propulsion head 2 does not have a bending connection part 11, which will be described later, but it is not limited to this, and a bending connection part 11 may be provided behind the hydraulic rotating device M provided inside the propulsion head body 7. In that case, if the number of bent connecting parts 11 provided on the main body of the propulsion head 7 is greater than the number of bent connecting parts 11 provided on all the underground propulsion pipes (first underground propulsion pipe 3, second underground propulsion pipe 4, and third and subsequent underground propulsion pipes 5) connected to the rear of the propulsion head 2, the rear of the main body of the propulsion head 7 may be designated as the first underground propulsion body 1.

[0022] The propulsion head body 7 consists of a front section 7a, a rear section 7b, a transmitter coil 9, and a coil cover section 9a. The rear end of the front section 7a is formed in a concave shape, and a female screw 7d for the front section 7d is threaded into this concave shape. The rear section 7b has a cylindrical coil holder section 7c that protrudes forward from its front end, and the transmitter coil 9 is wound around this coil holder section 7c so as to have an axis approximately parallel to the axis X of the propulsion head 2 (see Figure 3). The tip of the coil holder section 7c has a male screw 7e for the coil holder section that is threaded into the female screw 7d for the front section 7a at the rear end of the front section 7a. Then, the coil holder 7c around which the transmitting coil 9 is wound is inserted into the cylindrical coil cover 9a, and the male coil holder screw 7e threaded on the tip of the inserted coil holder 7c is screwed into the female coil holder screw 7d at the rear end of the front part 7a of the propulsion head body, thereby detachably connecting the rear part 7b of the propulsion head body to the front part 7a of the propulsion head body (see Figure 3). In this way, by inserting the coil holder 7c around which the transmitting coil 9 is wound into the cylindrical coil cover 9a, a cylindrical coil cover 9a is arranged around the transmitting coil 9, surrounding it from the outer circumference. The arrangement of the cylindrical coil cover 9a around the transmitting coil 9 protects the transmitting coil 9 from earth pressure and other forces that it receives during propulsion. The coil cover 9a is made of stainless steel, and multiple longitudinal through holes are provided at equal intervals in the longitudinal direction on the cylindrical side surface of the coil cover 9a, and these holes are filled with resin. In this way, the coil cover portion 9a is made of stainless steel, and through holes are provided on the side surface of the coil cover portion 9a arranged around the transmitting coil 9, so that the magnetic field emitted from the transmitting coil 9 can be transmitted to the receiving coil 18 (described later) without weakening the strength of the magnetic field.In this embodiment, a coil holding portion 7c is provided projecting forward from the front end of the rear portion 7b of the propulsion head body, and the male thread 7e of the coil holding portion at the tip of the coil holding portion 7c is screwed into the female thread 7d of the front portion of the propulsion head body at the rear end of the front portion 7a of the propulsion head body, thereby detachably connecting the rear portion 7b of the propulsion head body to the front portion 7a of the propulsion head body. However, the embodiment is not limited to this, and a coil holding portion may be provided projecting backward from the rear end of the front portion 7a of the propulsion head body, with a male thread 7e screwed into the rear end of the coil holding portion, and the front end of the rear portion 7b of the propulsion head body may be formed in a concave shape, with a female thread for the rear portion of the propulsion head body screwed into the concave shape to engage with the male thread 7e of the coil holding portion. In that case, the male thread of the coil holding portion provided at the rear end of the coil holding portion is screwed into the female thread for the rear portion of the propulsion head body at the front end of the rear portion 7b of the propulsion head body, thereby detachably connecting the rear portion 7b of the propulsion head body to the front portion 7a of the propulsion head body.

[0023] The first underground jacking pipe 3 is connected to the rear of the jacking head 2 via a non-bending connecting portion 10, and has five bending connecting portions 11 in the longitudinal direction that can be bent in the longitudinal vertical direction (see Figure 4(a)). Specifically, the non-bending connecting portion 10 at the rear of the jacking head 2 is fitted with the rear end protrusion 2a and rear end recess 2b of the jacking head 2 and the front end recess 3b and front end protrusion 3a of the first underground jacking pipe 3, and the rear end female screw component 2c provided at the rear end of the jacking head 2 and the front end male screw 3c formed at the front end of the first underground jacking pipe 3 are screwed together, thereby separating the rear end of the jacking head 2 from the front end of the first underground jacking pipe 3 (see Figure 6). Furthermore, the bent connecting portion 11 is constructed such that the cylindrical fitting insertion portion 12 is inserted into the cylindrical fitting insertion opening 13, and the insertion pin 14 is inserted into the cylindrical fitting insertion pin insertion hole 12a formed in the cylindrical fitting insertion portion 12 and the cylindrical fitting insertion opening pin insertion hole 13a formed in the first underground jacking pipe 3 and screwed in, thereby allowing the first underground jacking pipe 3 to bend in the longitudinal vertical direction with the insertion pin 14 as the pivot point (see Figure 5(a)). Here, the longitudinal vertical direction in which the first underground jacking pipe 3 is bent refers to the longitudinal vertical direction when the first underground jacking pipe 3 is propelled underground. In addition, the inside of the first underground jacking pipe 3 is cylindrical because the oil supply pipe 15 connected to the hydraulic rotating device M provided on the jacking head 2 passes through it (see Figure 5(b)). In this embodiment, the first underground jacking pipe 3 is provided with five bent connecting sections 11 in the longitudinal direction. However, it is not limited to this, and multiple bent connecting sections 11 may be provided in the longitudinal direction, such as four or more (preferably four to six), or five or more (more preferably five to seven). Also, in this embodiment, the first underground jacking pipe 3 is connected to the rear of the jacking head 2. However, it is not limited to this, and if the jacking head body 7 of the jacking head 2 is provided with a bent connecting section 11, the location of the bent connecting section 11 on the jacking head 2 may be designated as the first underground jacking pipe 3. In this case, the first underground jacking pipe 3 becomes the second underground jacking pipe 4, and the underground jacking pipes from the second underground jacking pipe 4 onward become the third and subsequent underground jacking pipes 5.Furthermore, in this embodiment, the cylindrical fitting insertion part 12 is inserted into the cylindrical fitting insertion opening 13, and the insertion pin 14 is inserted into the cylindrical fitting insertion part pin insertion hole 12a formed in the cylindrical fitting insertion part 12 and the cylindrical fitting insertion opening pin insertion hole 13a formed in the first underground jacking pipe 3 and screwed together, so that the first underground jacking pipe 3 is bent in the longitudinal vertical direction with the insertion pin 14 as the base point. However, the invention is not limited to this, and the bending connection part 11 may be bent using a spiral connecting member (connecting member) such as a coil spring (the same applies to the "bending connection part 11" below). Also, in this embodiment, the bending connection part 11 is bent in the longitudinal vertical direction, but the invention is not limited to this, and the bending connection part 11 may be bent in the longitudinal vertical direction, or the bending connection part 11 may be bent in the longitudinal up-down-left-right direction (the same applies to the "bending connection part 11" below). Furthermore, in this embodiment, the first underground jacking pipe 3 and the jacking head 2 are connected via the non-bending connecting portion 10, but the invention is not limited to this, and they may be connected via jacking pipe connecting means other than the non-bending connecting portion 10 (similar to the "non-bending connecting portion 10" below).

[0024] The second underground jacking pipe 4 is connected to the rear of the first underground jacking pipe 3 via a non-bending connector 10, and has four bending connectors 11 in the longitudinal direction that allow it to bend in the longitudinal vertical direction (see Figure 4(a)). Here, the non-bending connector 10 connecting the second underground jacking pipe 4 and the first underground jacking pipe 3 is the same as the non-bending connector 10 connecting the jacking head 2 and the first underground jacking pipe 3, and the bending connectors 11 of the second underground jacking pipe 4 are the same as the bending connectors 11 of the first underground jacking pipe 3 (jacking head 2), so their explanation is omitted. Also, the inside of the second underground jacking pipe 4 is cylindrical, similar to the first underground jacking pipe 3, because an oil supply pipe 15 connected to a hydraulic rotating device M provided on the jacking head 2 passes through it. In this embodiment, the second underground jacking pipe 4 has four bent connection points 11, which is one less than the first underground jacking pipe 3. However, the embodiment is not limited to this, and multiple connection points may be provided, with one to three (preferably one to two (more preferably two)) fewer than the first underground jacking pipe 3.

[0025] The third and subsequent underground jacking pipes 5 are composed of multiple underground jacking pipes connected to the rear of the second underground jacking pipe 4 via a non-bending connection section 10, and each underground jacking pipe has two bending connection sections 11 in the longitudinal direction that allow it to bend in the longitudinal vertical direction (see Figure 4(a)). Here, the non-bending connection section 10 to which the third and subsequent underground jacking pipes 5 and the second underground jacking pipe 4 are connected is the same as the non-bending connection section 10 to which the jacking head 2 and the first underground jacking pipe 3 are connected, and the bending connection section 11 of the third and subsequent underground jacking pipes 5 is the same as the bending connection section 11 of the second underground jacking pipe 4 (first underground jacking pipe 3), so the explanation is omitted. In addition, the inside of the third and subsequent underground jacking pipes 5 is cylindrical, similar to the first underground jacking pipe 3 and the second underground jacking pipe 4, because an oil supply pipe 15 connected to the hydraulic rotating device M provided on the jacking head 2 passes through it. In this embodiment, the third and subsequent underground jacking pipes 5 each have two bent connection points 11, which is two fewer than the second underground jacking pipe 4. However, the embodiment is not limited to this, and it is also possible to have one fewer bent connection point 11 than the second underground jacking pipe 4. In this way, multiple underground jacking pipes, including the first underground jacking pipe 3, the second underground jacking pipe 4, and the third and subsequent underground jacking pipes 5, are connected behind the jacking head 2.

[0026] The induction antenna 17 is equipped with a pair of receiving coils 18 inside, and these receiving coils 18 detect the strength of the magnetic field emitted from the transmitting coil 9 of the propulsion head 2. Here, the pair of receiving coils 18 of the induction antenna 17 are located inside the induction antenna 17 at positions symmetrically on both sides of the center (see Figure 8). The strength of the magnetic field emitted from the transmitting coil 9 of the propulsion head 2 is detected by the pair of receiving coils 18 located at positions symmetrically on both sides of the induction antenna 17, equidistant from the center, thereby enabling the detection of the propulsion position of the propulsion head 2 underground.

[0027] Next, we will describe the control box used for operating the underground propulsion system. Here, Figure 9 shows the operating surface of the control box used to operate the underground propulsion system in one embodiment of the present invention.

[0028] The operation box 20 is designed to be easily carried and includes a setting numerical input unit 21, a propulsion path display unit 22, an operation unit 23, and a propulsion position deviation angle display unit 27. The setting numerical input unit 21 receives input for terrain conditions such as the topography of the location where water pipes, etc., are laid, and the operating conditions of the underground propulsion body 1. When these conditions are input, the scale ratio between the distance axis, which relates to the horizontal distance between the propulsion start point ST and the propulsion destination setting point AR, and the height axis, which relates to the vertical height of the propulsion destination setting point AR relative to the propulsion start point ST, can also be set. The propulsion path display unit 22 displays terrain conditions and operating conditions entered using the setting numerical input unit 21, and during the propulsion operation of the underground propulsion body 1, it displays the attitude and position of the underground propulsion body 1, as well as the propulsion plan straight line PL (see Figure 10), which is the propulsion plan route of the propulsion head 2 that was planned in advance. Furthermore, the propulsion position deviation angle display unit 27 displays the angle at which the current position XX (see Figure 10) of the propulsion head 2 deviates from the propulsion plan line during propulsion. Specifically, by defining "X" as the length in the X-axis direction of the propulsion head's current position deviation, which is the length from the current position XX of the propulsion head 2 during propulsion to the propulsion plan line PL, and defining "Y" as the length in the Y-axis direction of the propulsion head's current position deviation, which is the length from the current plan line PP to the propulsion destination setting point AR, the propulsion position deviation angle Θ of the propulsion head 2 can be calculated using Θ = atan(X / Y) (see Figure 10). Here, Figure 10 is a reference diagram for calculating the propulsion position deviation angle of the propulsion head of an underground propulsion system in one embodiment of the present invention. Furthermore, the propulsion path indicator unit 22 is provided with an openable and closable cover body 26, and the operation unit 23 is a switch used for pushing and pulling operations of the underground propulsion body 1 and for rotating the pressure-receiving surface 8a provided on the propulsion head 2. Here, as described above, the underground propulsion body 1 automatically rotates the leading conductor 8 of the propulsion head 2, but if the propulsion head 2 collides with a rock or the like, the leading conductor 8 of the propulsion head 2 can also be manually rotated using the operation unit 23 of the operation box 20.The operation box 20 used in this embodiment is substantially identical to the propulsion control device described in Japanese Patent Publication No. 11-62478, so details will be omitted.

[0029] Next, the construction procedure for laying water pipes, etc., using an underground jacking body 1 that forms an underground hole for laying water pipes, etc., in one embodiment of the present invention will be explained with reference to Figure 11. Figure 11 is a flowchart of the method for laying water pipes, etc., using an underground jacking body in one embodiment of the present invention.

[0030] First, in S1, the propulsion plan straight line setting process is performed. In this "propulsion plan straight line setting process," the propulsion plan straight line PL, which is the propulsion plan route from the propulsion start point ST of the propulsion head 2 to the propulsion destination setting point AR, is input and set. Specifically, using the setting numerical input section 21 of the operation box 20, etc., "terrain conditions such as the propulsion start point ST and the propulsion destination setting point AR" and "operating conditions of the underground propulsion body 1 such as the propulsion direction of the propulsion head 2" are input, and the propulsion plan straight line PL is set based on the input terrain conditions and operating conditions. Then, this set propulsion plan straight line PL is displayed in the propulsion path display section 22 of the operation box 20. Here, this propulsion plan straight line setting process is performed by a propulsion plan straight line setting means, etc., in which the propulsion plan straight line setting means inputs and sets the propulsion plan straight line PL, which is the propulsion plan route from the propulsion start point ST of the propulsion head 2 to the propulsion destination setting point AR. Specifically, the propulsion start point ST and the propulsion destination setting point AR are input using the setting numerical input unit 21 of the operation box 20, and the propulsion plan straight line PL from the propulsion start point ST to the propulsion destination setting point AR is set as the propulsion plan route. Here, the propulsion plan route from the propulsion start point ST to the propulsion destination setting point AR of the propulsion head 2 is referred to as the propulsion plan straight line PL, but in reality, it is a straight line segment on the propulsion plan drawn from the propulsion start point ST to the propulsion destination setting point AR. In this embodiment, the propulsion plan straight line PL is set by inputting "terrain conditions" and "operating conditions of the underground propulsion body 1" using the setting numerical input unit 21 of the operation box 20 as the means for setting the propulsion plan straight line, but it is not limited to this, and the propulsion plan straight line PL may be set using equipment other than the setting numerical input unit 21 of the operation box 20. Then proceed to S2.

[0031] In S2, the underground pipe thrusting process is carried out. In this process, multiple underground pipes (2, 3, 4) behind the thrusting head 2 are pushed into the ground sequentially from the tip. Specifically, the thrusting head 2 is pushed into the ground first, and then, after passing through a loop described later, the first underground pipe 3, the second underground pipe 4, and the third and subsequent underground pipes 5 are pushed into the ground in order. Specifically, by using the operation unit 23 of the operation box 20 to push the thrusting head 2 (underground thrusting body 1, etc.), the thrusting device 6 located in the pit 16 formed at the thrusting start point ST pushes the underground thrusting body 1 into the ground from the thrusting head 2 at the tip in the order of thrusting head 2 → first underground pipe 3 → second underground pipe 4 → third and subsequent underground pipes 5. As a result, the first underground pipe 3, the second underground pipe 4, and the third and subsequent underground pipes 5 are pushed into the ground together with the thrusting head 2. In this way, each of the underground jacking pipes (2, 3, and 4) is pushed into the ground one by one. Then, the process moves on to S3.

[0032] In S3, the propulsion head current position detection process is performed. In this propulsion head current position detection process, the current position XX of the propulsion head 2, which is propelling through the ground, is detected. Specifically, as described above, the current position XX of the propulsion head 2 is detected by a pair of receiving coils 18 built into a guidance antenna 17 that is stationed at the propulsion destination setting point AR, based on the strength of the magnetic field generated by the transmitting coil 9 provided on the propulsion head 2. The strength of the magnetic field detected by the pair of receiving coils 18 built into the guidance antenna 17 is converted into voltage values, and the current position XX of the propulsion head 2 is detected by comparing these converted voltage values. In this embodiment, the current position XX of the propulsion head 2 is detected by a pair of receiving coils 18 built into the guidance antenna 17 based on the strength of the magnetic field generated by the transmitting coil 9 provided on the propulsion head 2. However, it is not limited to this, and the strength of the magnetic field generated by a magnetic field generating means such as a conductor may be detected by a magnetic field detection means such as a magnetic sensor. Then, the process proceeds to S4.

[0033] In S4, the propulsion position deviation angle calculation and storage process is performed. In this propulsion position deviation angle calculation and storage process, the propulsion position deviation angle Θ of the propulsion head 2 is calculated and stored, which is formed by the propulsion plan line PL set in the propulsion plan line setting process (S1) and the propulsion head propulsion position deviation line EL connecting the current position XX of the propulsion head 2 and the propulsion destination setting point AR (see Figure 10). Here, the calculation and storage of the propulsion position deviation angle Θ of the propulsion head 2 is performed by the propulsion head propulsion position deviation angle calculation and storage means, as described above. In other words, the calculation of the propulsion position deviation angle Θ of the propulsion head 2 is performed by the "propulsion head propulsion position deviation angle calculation unit (not shown)" of the propulsion head propulsion position deviation angle calculation and storage means, and the storage of the propulsion position deviation angle Θ of the propulsion head 2 is stored by the "propulsion head propulsion position deviation angle storage unit" of the propulsion head propulsion position deviation angle calculation and storage means. To explain this in more detail, the "propulsion head current position deviation length measurement unit (not shown)" of the propulsion head propulsion position deviation angle calculation and storage means measures the length of the propulsion head current position deviation in the X-axis direction, which is the length from the current position XX of the propulsion head 2 during propulsion to the propulsion plan line PL, to the current planning point PP of the propulsion head, which is the intersection of the perpendicular line drawn from the propulsion head 2 during propulsion to the propulsion plan line PL. At the same time, the length of the propulsion head current position deviation in the Y-axis direction, which is the length from the current planning point PP of the propulsion head to the propulsion destination setting point AR, is also measured. The "propulsion head position deviation length storage unit (not shown)" of the propulsion head propulsion position deviation angle calculation and storage means then stores the length of the propulsion head current position deviation in the X-axis direction and the length of the propulsion head current position deviation in the Y-axis direction measured by the propulsion head current position deviation length measurement unit. Then, the "propulsion head propulsion position misalignment angle calculation unit (not shown)" of the propulsion head propulsion position misalignment angle calculation and storage means sets the length X in the X-axis direction of the propulsion head's current position misalignment, which is stored in the propulsion head position misalignment length storage unit, as "X", and the length Y in the Y-axis direction of the propulsion head's current position misalignment, as "Y", and calculates the propulsion position misalignment angle Θ of the propulsion head 2 using the formula Θ = atan(X / Y) (see Figure 10). Then, the "propulsion head propulsion position misalignment angle storage unit" of the propulsion head propulsion position misalignment angle calculation and storage means stores the propulsion position misalignment angle Θ of the propulsion head 2 calculated by the propulsion head propulsion position misalignment angle calculation unit.In this embodiment, the "propulsion head position deviation length storage unit" and the "propulsion head position deviation angle storage unit" of the propulsion head propulsion position deviation angle calculation storage means are described as separate storage units. However, the "propulsion head propulsion position deviation angle storage unit" and the "propulsion head propulsion position deviation angle storage unit" may be stored in a single recording unit. Also, although the propulsion head propulsion position deviation line EL is described as connecting the current position XX of the propulsion head 2 and the propulsion destination setting point, in reality, it is a line segment on the propulsion head propulsion position deviation line drawn straight from the current position XX of the propulsion head 2 to the propulsion destination setting point. Then, proceed to S5.

[0034] In S5, the propulsion head propulsion status detection and display process is performed. In this propulsion head propulsion status detection and display process, the propulsion status of the propulsion head 2 is detected and displayed on the propulsion path display unit 22 of the operation box 20. At the same time, the propulsion position deviation angle Θ, which is the deviation of the propulsion position from the propulsion plan line at the current position XX of the propulsion head 2, is displayed on the propulsion position deviation angle display unit 27. Specifically, as described above, the strength of the magnetic field generated by the emitting coil 9 provided on the propulsion head 2 is detected by a pair of receiving coils 18 built into the guidance antenna 17, which is positioned at the propulsion destination setting point AR. The propulsion status of the propulsion head 2 is detected by comparing the voltage values ​​obtained by the pair of receiving coils 18 built into the guidance antenna 17, after the magnetic field strengths detected by the pair of receiving coils 18 have been converted into voltage values. In other words, by comparing the voltage values ​​converted by the pair of receiving coils 18 in the guidance antenna 17, it is detected that the propulsion head 2 is deviating from the propulsion plan line towards the side with the larger voltage value. The detected propulsion status of the propulsion head 2 is then displayed on the propulsion path display unit 22 of the operation box 20. In addition, the propulsion position deviation angle Θ of the propulsion head 2 is displayed on the propulsion position deviation angle display unit 27. The propulsion status of the propulsion head 2 is detected in the same manner as described in Japanese Patent Application Publication No. 11-62478. In this embodiment, the propulsion status of the propulsion head 2 is detected by a pair of receiving coils 18 built into the induction antenna 17, based on the strength of the magnetic field generated by the transmitting coil 9 provided on the propulsion head 2. However, it is not limited to this, and as described above, the strength of the magnetic field generated by a magnetic field generating means such as a conductor may be detected by a magnetic field detection means such as a magnetic sensor. Then, proceed to S6.

[0035] In S6, a propulsion head propulsion position deviation correction control process is performed. In this propulsion head propulsion position deviation correction control process, if the current position XX of the propulsion head 2 deviates from the propulsion plan path (propulsion plan straight line), the deviation is corrected. Specifically, if the current position XX of the propulsion head 2 detected by the propulsion head current position detection process (S3) is deviating from the propulsion plan straight line PL connecting the propulsion start point ST of the propulsion head 2 and the propulsion destination setting point AR, the propulsion head 2 is controlled to reduce the propulsion position deviation angle Θ formed by the propulsion plan straight line PL connecting the propulsion start point ST and the propulsion destination setting point AR, and the propulsion head propulsion position deviation straight line EL connecting the current position XX of the propulsion head 2 and the propulsion destination setting point AR. In other words, the propulsion head 2 is controlled to reduce the propulsion position deviation angle Θ of the propulsion head 2 calculated by the propulsion head propulsion position deviation angle calculation and storage means (S4), and the propulsion head 2 is propelled toward the propulsion destination setting point AR. This propulsion control of the propulsion head 2 is performed by a control means (not shown). In this way, the propulsion head 2 is controlled to minimize the propulsion position deviation angle Θ calculated by the propulsion head propulsion position deviation angle calculation and storage means. As a result, the propulsion head 2 can be automatically propelled without the operator having to rotate it, reducing the physical and mental burden on the operator from operating the underground propulsion body 1 and alleviating operator fatigue. Furthermore, because the underground propulsion body 1 can be operated automatically, even operators unfamiliar with operating the propulsion head 2 can easily operate the underground propulsion body 1. In addition, since the propulsion position deviation angle Θ of the propulsion head 2 becomes smaller at positions far from the propulsion destination setting point AR, the propulsion position deviation of the propulsion head 2 from the propulsion plan line PL can be corrected by using the sufficient propulsion distance to bring the propulsion head 2's propulsion position closer to the propulsion plan line AR, thereby gently changing the direction of the propulsion head 2.In this way, by utilizing the distance between the current position XX of the propulsion head 2 and the propulsion destination setting point AR, the deviation of the propulsion position of the propulsion head 2 from the propulsion plan straight line PL can be corrected while avoiding abrupt changes in the direction of the propulsion head 2. Furthermore, since the deviation of the propulsion position of the propulsion head 2 from the propulsion plan straight line PL mainly occurs at a position far from the propulsion destination setting point AR, a large load on the propulsion head 2 and other components is not placed over the entire area from the propulsion start point ST to the propulsion destination setting point AR, resulting in no large loss of propulsion thrust and preventing breakage of the propulsion head 2 and other components. In this embodiment, the propulsion head propulsion position deviation correction control step (S6) is always performed after the propulsion head propulsion status detection display step (S5), but it is not limited to this, and the propulsion position deviation angle Θ of the propulsion head 2 may be controlled by the control means to reduce the propulsion position deviation angle Θ of the propulsion head 2 when the propulsion position deviation angle Θ of the propulsion head 2 exceeds a predetermined angle. Here, this "predetermined angle" can be calculated using Θ1 = atan(20 / Y) (see Figure 10). This is the length of the X-axis direction of the thrust head's current position deviation, which is the length from the current position XX of the thrust head 2 during thrust to the thrust plan line PL, which is the intersection of the perpendicular line drawn from the current position XX of the thrust head 2 during thrust to the thrust plan line PL, to the thrust plan line PL, which is the length of the Y-axis direction of the thrust head's current position deviation, which is the length from the thrust plan line PP to the thrust destination setting point AR. In this case, "20" is the allowable position deviation length X of the X-axis direction of the thrust head's current position deviation. To illustrate this formula simply, for example, if the length of the propulsion plan straight line PL connecting the propulsion start point ST and the propulsion destination setting point AR is 10m (1000cm), then the predetermined angle Θ1 at 60cm from the propulsion start point ST will be 1.2 degrees (atan(20 / 940)), and the predetermined angle Θ1 at 940cm from the propulsion start point ST will be 18.4 degrees (atan(20 / 60)). In this way, when the propulsion position deviation angle Θ of the propulsion head 2 exceeds a predetermined angle, the propulsion direction of the propulsion head 2 can be stably controlled by controlling it so that the propulsion position deviation angle Θ of the propulsion head 2 becomes smaller. Then proceed to S7.

[0036] In S7, a decision is made as to whether to rotate the thrusting head 2 (leading conductor 8). To briefly explain the situations in which S7 is judged as "NO" or "YES," in the "underground thrusting pipe insertion process," the underground thrusting pipes (2, 3, and 4) are inserted into the ground one by one in sequence. Once each of the underground thrusting pipes (2, 3, and 4) has been inserted, the rotation of the thrusting head 2 (leading conductor 8) is stopped, and then the thrusting head 2 (leading conductor 8) is rotated again when the insertion of the next underground thrusting pipe (3 and 4) begins. Thus, a "NO" judgment is made when the insertion of an underground thrusting pipe is complete, and a "YES" judgment is made when the insertion of the next underground thrusting pipe begins. A "NO" judgment is also made when the insertion of all underground thrusting pipes is complete. If a "NO" judgment is made, the process proceeds to S9, and if a "YES" judgment is made, the process proceeds to S8.

[0037] In S8, the thrust head rotation process is performed. In this thrust head rotation process, the leading conductor 8 of the thrust head 2, which is connected to the leading end of the first underground thrust pipe 3 pushed in by the underground thrust pipe pushing process (S2), is rotated around its longitudinal axis (see Figure 2). As the thrust head 2's pressure-receiving surface 8a receives earth pressure during thrusting, the thrust head 2 is pushed in the direction of the inclination of the pressure-receiving surface 8a, allowing the thrust direction of the thrust head 2 to be flexibly changed. Specifically, by rotating the leading conductor 8 of the thrust head 2 to the left or right, the leading conductor 8 of the thrust head 2 is rotated around its longitudinal axis, and as the leading conductor 8 of the thrust head 2 rotates around its longitudinal axis, the pressure-receiving surface 8a of the thrust head 2 is also rotated. Here, both the left and right rotations of the leading conductor 8 of the thrust head 2 are performed with the same rotation time and number of rotations. As a result, the leading conductor 8 of the propulsion head 2 repeatedly rotates in the same direction left → right → left → right, allowing the propulsion head 2 to propel itself straight while meandering from side to side. Although the operation of rotating left or right using the operation unit 23 of the operation box 20 requires some skill, if the current position of the propulsion head 2 deviates from the propulsion plan straight line PL connecting the propulsion start point ST and the propulsion destination setting point AR, the propulsion head propulsion position deviation correction control process (S6) described above controls the propulsion position deviation angle Θ of the propulsion head 2 to decrease, and the leading conductor 8 of the propulsion head 2 automatically rotates left or right. Therefore, even an operator unfamiliar with operating the propulsion head 2 can accurately propel the propulsion head 2 along the propulsion plan straight line and efficiently propel it to the propulsion destination setting point AR. Furthermore, by propelling the propulsion head 2 along the propulsion plan straight line PL, an underground hole is formed in the ground. Then, in S7, the process of S8→S2→S3→S4→S5→S6→S7→S8 is repeatedly performed until it is determined that the propulsion head 2 (leading conductor 8) should not be rotated. If "NO" is determined in S8, the process proceeds to S9.

[0038] In S9, it is determined whether to terminate the pushing of the underground propulsion body 1 into the ground. Here, the pushing of the underground propulsion body 1 is terminated after the propulsion head 2 reaches the ground surface of the propulsion destination setting point AR. A hole for the propulsion destination setting point (not shown) has been dug in advance on the ground surface of the propulsion destination setting point AR as a marker for the propulsion destination setting point. If it is determined to be "YES", the process proceeds to S10, and if it is determined to be "NO", the process proceeds to S2, and the process of S9→S2→S3→S4→S5→S6→S6→("S8" or "S9")→S2 is repeated until it is determined to be "NO".

[0039] In S10, the underground pipe thrusting completion process is carried out. In this underground pipe thrusting completion process, the thrusting of the underground thrusting body 1 into the ground is completed. Specifically, the thrusting of the underground thrusting body 1 into the ground is completed by performing the thrusting completion operation of the underground thrusting body 1 using the operation control unit 23 of the operation box 20. The process proceeds to S11.

[0040] In S11, the propulsion head sheath pipe connection process is performed. In this propulsion head sheath pipe connection process, the tip of the propulsion head 2 is rotated by the propulsion head rotation process (S8), changing the propulsion direction of the propulsion head 2. After the propulsion head 2 reaches the ground surface of the propulsion destination setting point AR, the tip of the propulsion head 2 protruding from the ground surface is connected to the end of the sheath pipe 19 by an O-shaped fitting 24 (see Figure 1(b)). A pipe 25 is inserted inside the sheath pipe 19. In this embodiment, the tip of the propulsion head 2 and the tip of the sheath pipe 19 are connected by an O-shaped fitting 24, but the invention is not limited to this, and the tip of the propulsion head 2 and the tip of the sheath pipe 19 may be connected by a connecting means such as a swivel double hook. Furthermore, in this embodiment, the tip of the propulsion head 2 is connected to the tip of the sheath tube 19, but this is not limited to this, and the tip of the propulsion head 2 may be connected to the tip of a propulsion head connector other than the sheath tube 19, in which case the "propulsion head sheath tube connection step" becomes the "propulsion head connector connection step". Then proceed to S12.

[0041] In S12, the supply pipe undergrounding process is carried out. In this supply pipe undergrounding process, the conduit pipe 19, which is connected to the thrusting head 2 by the thrusting head conduit connection process (S11), is pulled in the opposite direction to the thrusting direction from which it was pushed in by the underground thrusting pipe underground pushing process (S2), together with the first underground thrusting pipe 3, the second underground thrusting pipe 4, and the third and subsequent underground thrusting pipes 5. Specifically, by using the operation control section 23 of the operation box 20 to operate the pull-in operation of the underground thrusting body 1, the third and subsequent underground thrusting pipes 5 are pulled in first by the thrusting device 6 located in the pit 16 formed at the thrusting start point ST, and then, after passing through a loop described later, the third and subsequent underground thrusting pipes 5 → second underground thrusting pipe 4 → first underground thrusting pipe 3 → thrusting head 2 are pulled in in that order, and the conduit pipe 19, which is connected to the thrusting head 2 at the tip of the underground thrusting body 1, is pulled in the opposite direction to the thrusting direction from which it was pushed in by the underground thrusting pipe underground pushing process (S2). In this embodiment, during the underground supply pipe installation process, a conduit pipe 19 with a pipe 25 inside is pulled in. However, the process is not limited to this; the conduit pipe 19 may be pulled in alone, and after the conduit pipe 19 is laid underground, a water pipe or the like may be inserted into the conduit pipe 19. Then, the process proceeds to S13.

[0042] In S13, a decision is made as to whether to terminate the pulling in of the conduit pipe 19. Here, the pulling in of the conduit pipe 19 is terminated after the conduit pipe 19 reaches the ground surface at the starting point ST. If "NO" is determined in S13, the process of S13 → S12 → S13 is repeated until "YES" is determined, and if "YES" is determined, the process proceeds to S14. As a result, the conduit pipe 19 connected to the thrust head 2 is laid underground across the underground hole from the starting point ST to the thrust destination setting point AR, and the pipe 25 inside the conduit pipe 19 is also laid underground.

[0043] In S14, the jacking head conduit separation process is carried out. In this jacking head conduit separation process, after the conduit 19 has been pulled up to the ground surface near the jacking start point ST by the supply pipe undergrounding process (S12), the conduit 19 is separated from the tip of the jacking head 2. Specifically, the O-shaped fitting 24 connecting the tip of the conduit 19 and the tip of the jacking head 2 is removed, and the conduit 19 is separated from the tip of the jacking head 2. After that, processing according to the respective purpose, such as laying water pipes, is carried out. With this, the method of laying water pipes, etc. using the underground jacking body 1 is completed.

[0044] As explained above, the propulsion head propulsion position deviation correction control process (S6) controls the propulsion head 2 so that when the current position XX of the propulsion head 2 is deviating from the propulsion plan straight line PL connecting the propulsion start point ST of the propulsion head 2 and the propulsion head propulsion position deviation straight line EL connecting the current position XX of the propulsion head 2 and the propulsion head propulsion position deviation AR, the propulsion head 2 is propelled automatically without the operator having to rotate the propulsion head 2. This reduces the physical and mental burden on the operator from operating the underground propulsion body 1, thereby reducing operator fatigue. Furthermore, because the underground propulsion body 1 can be operated automatically, even operators unfamiliar with operating the propulsion head 2 can easily operate the underground propulsion body 1. Furthermore, the angle Θ of the propulsion position deviation of the propulsion head 2 becomes smaller at positions far from the propulsion target point AR. Therefore, the further the propulsion position of the propulsion head 2 is from the propulsion target point AR, the more the deviation of the propulsion head 2 from the propulsion plan line PL can be corrected by gradually changing the direction of the propulsion head 2. In this way, by utilizing the length of the distance between the propulsion position of the propulsion head 2 and the propulsion target point AR, the deviation of the propulsion head 2 from the propulsion plan line PL can be corrected while avoiding abrupt changes in the direction of the propulsion head 2. Moreover, since the deviation of the propulsion head 2 from the propulsion plan line PL mainly occurs at positions far from the propulsion target point AR, a large load on the propulsion head 2 and other components will not be placed over the entire region from the propulsion start point ST to the propulsion target point AR, thus preventing a large loss of propulsion thrust and preventing breakage of the propulsion head 2 and other components.

[0045] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0046] 1 Underground propellant 2. Propulsion head 2a Protruding part at the rear end of the propulsion head 2b Recess at the rear end of the propulsion head 2c Female threaded component at the rear end of the propulsion head 3 First underground propulsion tube 3a Protruding front end of the first underground pipe 3b First underground propulsion pipe front end recess 3c First underground jacking pipe front end male thread 4 Second underground propulsion pipe 5 Third underground propulsion pipe 6 Propulsion device 7. Propulsion head main body 7a Front part of the propulsion head body 7b Rear section of the propulsion head body 7c Coil holding section 7d Female thread on the front part of the thruster head body 7e Coil holding part male screw 8. Leading conductor 8a Pressure receiving surface 9. Oscillating coil 9a Coil cover section 10 Non-bending connection 11 Bend connection part 12 Cylindrical fitting insertion part 12a Cylindrical fitting insertion part pin insertion hole 13. Cylindrical fitting insertion port 13a Cylindrical fitting insertion port pin insertion hole 14 Insertion pins 15 Oil pipe 16 Pit 17 Induction Antenna 18 Receiving coil 19. Sheath pipe 20 Control Box 21 Setting value input section 22 Propulsion path display section 23. Operation Unit 24 O-shaped fittings 25 pipes 26 Cover body M Hydraulic Rotating Device ST promotion starting point AR propels you to the designated location. XX's current location

Claims

1. A ground thrusting body is used to form underground holes for laying water pipes, etc., with a thrusting head whose tip rotates around its longitudinal axis as it propels itself underground, to which multiple underground thrusting pipes are connected at the rear. A pressure-receiving surface is formed at the tip, which is inclined with respect to the longitudinal axis, and as the pressure-receiving surface is propelled, it receives earth pressure, thereby propelling the propulsion head in the direction of the inclination of the pressure-receiving surface. A series of underground jacking pipes are connected to the rear of the jacking head via jacking pipe connecting means, and each pipe has multiple bendable connecting sections that can be bent in the longitudinal direction, and A propulsion plan straight line input setting means inputs and sets a propulsion plan straight line, which is the propulsion plan route from the propulsion start point to the propulsion destination setting point of the propulsion head, A propulsion head propulsion position deviation angle calculation and storage means calculates and stores the propulsion head propulsion position deviation angle formed by the propulsion plan line and the propulsion head propulsion position deviation line connecting the current position of the propulsion head and the propulsion destination setting point, The system includes a control means that controls the propulsion head so that the propulsion position deviation angle of the propulsion head, calculated by the propulsion head propulsion position deviation angle calculation and storage means, becomes smaller, and propulsion control is performed so that the propulsion head moves toward the propulsion destination setting point. The underground propulsion system is characterized in that the angle of deviation of the propulsion head formed by the propulsion plan line and the propulsion head propulsion position deviation line is controlled to be small, so that the propulsion head is automatically propelled to the propulsion destination setting point without the operator having to rotate the propulsion head, thereby reducing the degree of physical and mental burden on the operator and reducing operator fatigue. Furthermore, because it can be operated automatically, even operators who are not accustomed to operating the propulsion head can easily operate it. In addition, by eliminating large changes in direction of the propulsion head and the underground propulsion pipe, it is possible to prevent large loads from being placed on the propulsion head and the underground propulsion pipe, thereby reducing underground propulsion loss and preventing breakage of the propulsion head and the underground propulsion pipe.

2. The aforementioned propulsion head propulsion position displacement angle calculation and storage means is: A propulsion head current position deviation length measuring unit measures the distance from the current position of the propulsion head during propulsion to the current propulsion plan line, which is the distance from the current position of the propulsion head to the current propulsion plan line, which is the intersection of the perpendicular line drawn from the current propulsion plan line with the current propulsion plan line, and the distance from the current propulsion plan line to the propulsion destination setting point, which is the distance from the current propulsion plan point to the propulsion destination setting point. A propulsion head position misalignment length storage unit stores the X-axis length of the propulsion head's current position misalignment measured by the propulsion head current position misalignment length measuring unit, and the Y-axis length of the propulsion head's current position misalignment. The propulsion head position displacement angle Θ is calculated by a propulsion head propulsion position displacement angle calculation unit, where X is the length of the current position displacement of the propulsion head in the X-axis direction and Y is the length of the current position displacement of the propulsion head in the Y-axis direction, and Θ is calculated by Θ = atan(X / Y). A propulsion head propulsion position misalignment angle storage unit stores the propulsion position misalignment angle Θ of the propulsion head calculated by the propulsion head propulsion position misalignment angle calculation unit, The underground propulsion system according to claim 1, characterized by having the following features.

3. The underground propulsion system according to claim 2, characterized in that the control means controls the propulsion position displacement angle of the propulsion head to decrease when the propulsion position displacement angle of the propulsion head exceeds a predetermined angle.

4. The underground propulsion system according to claim 3, characterized in that the predetermined angle Θ1 is determined by Θ1 = atan(20 / Y).

5. A propulsion plan straight line setting step in which the propulsion plan straight line, which is the propulsion plan route from the propulsion start point of the propulsion head to the propulsion destination setting point, is input and set, The underground pipe thrusting process involves pushing the multiple underground pipes located behind the thrusting head into the ground sequentially from their tips, The underground jacking pipe underground pushing process includes a jacking head rotation process in which the tip of the jacking head connected to the tip of the underground jacking pipe that has been pushed in by the underground jacking pipe underground pushing process is rotated around the longitudinal axis, A propulsion head current position detection step in which the current position of the propulsion head that is being propelled underground is detected, If the current position of the propulsion head detected by the propulsion head current position detection step is deviating from the propulsion plan line connecting the propulsion start point and the propulsion destination setting point of the propulsion head, the propulsion head propulsion position deviation correction control step controls the propulsion head so that the propulsion position deviation angle of the propulsion head formed by the propulsion plan line connecting the propulsion start point and the propulsion destination setting point and the propulsion head propulsion position deviation line connecting the current position of the propulsion head and the propulsion destination setting point becomes smaller. The propulsion head rotation process rotates the tip of the propulsion head, changing the direction of propulsion of the propulsion head, and after the propulsion head reaches the ground surface of the propulsion destination setting point, the propulsion head tip protruding from the ground surface is connected to the end of the propulsion head connector by a connecting means in a propulsion head connector connection process, The propulsion head connector, connected to the propulsion head by the propulsion head connection process, is pulled in a direction opposite to the propulsion direction in which it was pushed in by the underground propulsion pipe underground pushing process, along with a plurality of underground propulsion pipes, in a supply pipe underground pulling process. The method for laying an underground propulsion system according to claim 2, characterized in that the propulsion head propulsion position deviation correction control step controls the propulsion head so that the propulsion position deviation angle of the propulsion head formed by the propulsion plan straight line connecting the propulsion start point of the propulsion head and the propulsion destination setting point and the propulsion head propulsion position deviation straight line connecting the current position of the propulsion head and the propulsion destination setting point becomes smaller, so that the propulsion head is automatically propelled to the propulsion destination setting point without the operator having to rotate the propulsion head, thereby reducing the degree of physical and mental burden on the operator and reducing operator fatigue, and because it can be operated automatically, even an operator who is not familiar with operating the propulsion head can easily operate it, and furthermore, by eliminating large changes in direction of the propulsion head and the underground propulsion pipe, it is possible to prevent large loads from being placed on the propulsion head and the underground propulsion pipe, thereby reducing underground propulsion loss and preventing breakage of the propulsion head and the underground propulsion pipe.

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