JP2008240456A - Shield machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shield machine capable of minimizing prying-drilling force of two hydraulic jacks for driving a beam cutter and preventing these hydraulic jacks from being damaged. <P>SOLUTION: In this shield machine, a jack thrust calculated value of the second hydraulic jack 40b is decided based on an oil pressure detected value of the second hydraulic jack 40b detected by second oil pressure detection means 55b, 56b, a prying-drilling force calculated value of the first hydraulic jack 40a and a prying-drilling force calculated value of the second hydraulic jack 40b fixed in accordance with the jack thrust calculated value and a rotation angle detected by a rotation angle detection means 53 are decided, respectively, a jack thrust set value of the second hydraulic jack 40b is decided to make the sum of a prying-drilling force calculated value in the direction crossing that of jack thrust orthogonally of the first hydraulic jack 40a and a prying-drilling force calculated value in the direction crossing that of jack thrust orthogonally of the second hydraulic jack 40b zero, and opening degrees of second control valves 48b, 50b are controlled to make deviation of the jack thrust calculated value of the second hydraulic jack 40b from the jack thrust set value zero. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a shield machine for excavating a deformed section such as a horseshoe-shaped section, an elliptical section, or a rectangular section, and more particularly to a shield machine having a beam cutter driven by two hydraulic jacks.

  In the shield machine, a tunnel is constructed by excavating a natural ground with a rotary cutter provided at the front of the shield body and sequentially assembling the segments behind it. A plurality of bits are arranged in front of the rotating cutter, and the rotating cutter is rotated to excavate a natural ground with the bits.

  By the way, since the occupation width in the horizontal direction of the road is larger than the occupation width in the vertical direction, the cross section of the road tunnel is ideally a horseshoe-shaped cross section in which the horizontal direction is wider than the vertical direction. That is, when the road tunnel has a horseshoe-shaped cross section, there is an advantage that less space is used in the vertical direction than a circular cross section, and the construction cost is low.

  As a shield machine for excavating a deformed cross section such as a horseshoe cross section, an elliptical cross section or a rectangular cross section, for example, a rotary cutter provided at the front part of the shield body and driven to rotate around an axis parallel to the excavation direction, 2. Description of the Related Art An overcutter that is provided on a cutter pork of a rotary cutter and is capable of protruding and retracting radially outward from the outer peripheral edge of the rotary cutter is known. In such a shield machine, the overcutter protrudes radially outward from the outer peripheral edge of the rotating cutter, and the overcutter excavates a region radially outward from the outer peripheral edge of the rotating cutter.

  In addition, the cited document 1 describes a shield machine having a swing cutter that can be opened and closed on the outer periphery of a circular main cutter.

JP 11-303581 A

  The present inventors are newly developing a shield machine that excavates an irregular cross section such as a horseshoe cross section, an elliptical cross section, or a rectangular cross section.

  This shield machine has two hydraulic jacks arranged on a cutter frame rotatably provided at the front part of the shield main body so as to be at a predetermined angle along the radial direction and in the circumferential direction of the cutter frame. And a beam cutter (trademark registration pending), which is formed in a beam shape, and a portion on the inner side in the longitudinal direction from the end portion in the longitudinal direction is rotatably supported by the extendable end portions of the two hydraulic jacks.

  In this shield machine, by extending and contracting the two hydraulic jacks, one of the two hydraulic jacks is moved outward in the radial direction of the cutter frame, and the other elastic end is moved in the radial direction of the cutter frame. The beam cutter is moved inward so that the longitudinal end of the beam cutter protrudes radially outward of the cutter frame.

  In such a shield machine, since the distance between the expansion and contraction ends of the two hydraulic jacks is always constant, it is necessary to accurately control the stroke of the expansion and contraction of the two hydraulic jacks. The jack control method has not been established.

  In the shield machine as described above, it is conceivable to control the two hydraulic jacks using the stroke as a control target (stroke control). When the two hydraulic jacks are controlled using only the stroke as the control target in this way, When the two hydraulic jacks expand and contract against the force (excavation force) that the beam cutter receives from the ground, the hydraulic pressures of the two hydraulic jacks antagonize and rise, and the two hydraulic jacks are orthogonal to the longitudinal direction. There is a risk that the force acting in the direction (pricking force) increases, and the hydraulic jack is damaged by the prying force of the hydraulic jack.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a shield machine capable of minimizing the twisting force of two hydraulic jacks that drive a beam cutter and preventing the hydraulic jacks from being damaged.

  In order to achieve the above object, the present invention provides a cutter frame rotatably provided at the front portion of a shield body, and a predetermined angle with each other along the radial direction of the cutter frame and in the circumferential direction of the cutter frame. The first and second hydraulic jacks arranged in this manner, and a beam-like shape, the inner part in the longitudinal direction of the longitudinal end of the first and second hydraulic jacks is rotatable to the telescopic end of the first and second hydraulic jacks In a shield machine equipped with a supported beam cutter, rotation angle detection means for detecting the rotation angle of the cutter frame, first stroke detection means for detecting the stroke of the first hydraulic jack, A second hydraulic pressure detecting means for detecting the hydraulic pressure of the second hydraulic jack; and a first hydraulic pressure for controlling the amount of oil supplied to the first and second hydraulic jacks. A second control valve and control means for controlling the opening degree of the first and second control valves, the control means being configured to control the first hydraulic jack based on the rotation angle detected by the rotation angle detection means. A stroke set value is determined, and the opening of the first control valve is adjusted so that the deviation between the stroke set value and the stroke detection value of the first hydraulic jack detected by the first stroke detection means becomes zero. And controlling a jack thrust calculation value of the second hydraulic jack based on a hydraulic pressure detection value of the second hydraulic jack detected by the second hydraulic pressure detecting means, and detecting the jack thrust calculation value and the rotation angle detection. Calculated in the direction orthogonal to the jack thrust of the first hydraulic jack determined according to the rotation angle detected by the means and the direction orthogonal to the jack thrust of the second hydraulic jack Determine the torsional force calculated value, and set the jack thrust setting value of the second hydraulic jack so that the sum of the calculated value of the first hydraulic jack and the calculated value of the second hydraulic jack becomes zero. And the opening degree of the second control valve is controlled so that the deviation between the jack thrust setting value and the jack thrust calculation value of the second hydraulic jack becomes zero.

  According to the present invention, it is possible to minimize the twisting force of the two hydraulic jacks that drive the beam cutter and to prevent the hydraulic jacks from being damaged.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a front view of a shield machine according to an embodiment of the present invention. 2 is a cross-sectional view taken along line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 5 is a cross-sectional view taken along line VV in FIG.

  As shown in FIGS. 1 to 4, the shield machine 1 includes a shield main body 2 and a rotary cutter 3 that is rotatably provided at the front portion of the shield main body 2 and excavates a circular cross section. The shield body 2 has a horseshoe-shaped cross section that is wider in the lateral direction (left and right direction in FIG. 1) than in the vertical direction (up and down direction in FIG. 1), and has the widest width on the lower side than the center in the vertical direction. It is formed as follows. The rotary cutter 3 is driven to rotate around an axis parallel to the excavation direction.

  At the rear of the shield body 2, there are an erector (not shown) for assembling segments in a hole excavated by the rotary cutter 3 and a beam cutter 4 to be described later to construct a tunnel (road tunnel), A plurality of shield jacks (not shown) are provided on the inner periphery at predetermined intervals, and a reaction force is applied to the segments to propel the shield body 2.

  A chamber 6 is formed between the rotary cutter 3 and the bulkhead (partition wall) 5 provided in the vicinity of the front end of the shield body 2 to take in the earth and sand (excavated earth and sand) excavated by the rotary cutter 3 and the beam cutter 4. The A screw conveyor 7 that passes through the bulkhead 5 and opens into the chamber 6 is provided below the bulkhead 5.

  The rotary cutter 3 is rotatably provided on the bulkhead 5. The rotary cutter 3 has a cutter frame 8 that extends radially outward from the center of rotation and is rotated about an axis parallel to the excavation direction. On the front surface of the cutter frame 8, a center bit 9 is disposed at the center in the radial direction, and a plurality of cutter bits 10 are disposed on the outer peripheral side of the center bit 9. The center bit 9 and the cutter bit 10 are brought into contact with a ground mountain radially inward from the outer peripheral edge of the rotary cutter 3. On the rear surface of the cutter frame 8, a stirring blade 11 is provided to extend rearward and stir the excavated earth and sand in the chamber 6.

  The cutter frame 8 includes a center member 12 and a plurality (eight in the illustrated example) of cutter spokes 13 and 14 attached to the center member 12 in a radial pattern. That is, each of the cutter spokes 13 and 14 extends radially outward from the rotation center of the rotary cutter 3.

  Here, the cutter spokes 13 and 14 are composed of two types, a first cutter pork 13 and a second cutter pork 14. In the present embodiment, four of the eight cutter spokes 13 and 14 are the first cutter pork 13 and the remaining four are the second cutter pork 14.

  The first cutter pork 13 is adjacent to at least one other first cutter pork 13 at a predetermined interval in the circumferential direction of the rotary cutter 3.

  The second cutter pork 14 is adjacent to the first cutter pork 13 or another second cutter pork 14 at a predetermined interval in the circumferential direction of the rotary cutter 3.

  The first cutter spokes 13 adjacent to each other in the circumferential direction of the rotary cutter 3, the second cutter spokes 14 adjacent to each other in the circumferential direction of the rotary cutter 3, or the first cutter pork 13 and the first cutter spoke 13 adjacent to each other in the circumferential direction of the rotary cutter 3. The two-cut spokes 14 are connected by an intermediate member 16 at their radially intermediate portions.

  The first cutter spokes 13 adjacent to each other in the circumferential direction are connected to each other at the outer peripheral portion by an outer peripheral member 17a.

  The second cutter spokes 14 adjacent to each other in the circumferential direction are connected by an outer peripheral member 17b at the outer peripheral portion thereof.

  The second cutter pork 14 is formed in a box shape whose side is opened so that the beam cutter 4 can be inserted when the beam cutter 4 is driven (see FIGS. 1, 2 and 5). ).

  A ring-shaped member 21 having a gear 20 is rotatably supported on the bulkhead 5. The ring-shaped member 21 is connected to the cutter frame 8 by a plurality of intermediate beams 22 extending rearward from the cutter frame 8 of the rotary cutter 3. A plurality of intermediate beams 22 are provided at predetermined intervals in the circumferential direction of the rotary cutter 3. In the shield body 2, a plurality of drive motors 23 (hydraulic motors in the present embodiment) for rotating the ring-shaped member 21 are provided. A pinion 24 is attached to the drive motor 23, and the pinion 24 meshes with the gear 20 provided on the ring-shaped member 21.

  The bulkhead 5 is provided with a support mechanism 25 that rotatably supports the ring-shaped member 21. The support mechanism 25 is housed in the casing 26, bearings 27 and 28 for supporting the ring-shaped member 21, and a seal mechanism 29 for preventing earth and sand from entering the shield body 2. have.

  The rotary cutter 3 is arranged so as to extend from a predetermined position radially inward of the outer peripheral edge of the rotary cutter 3 to the outer side of the rotary cutter 3 in a substantially radial direction, and at a predetermined angle with respect to the circumferential direction of the rotary cutter 3. Two guides are provided.

  In the present embodiment, the two guides are provided on two first cutter spokes 13 adjacent to each other in the circumferential direction of the rotary cutter 3, and a fixed spoke 30 attached to the center member 12 and a fixed spoke 30. And a guide spoke 31 that is movable in the radial direction of the rotary cutter 3 (longitudinal direction of the fixed spoke 30).

  Each first cutter pork 13 is provided with a support portion 32 that is movable along the longitudinal direction of each first cutter pork 13, that is, along the radial direction of the rotary cutter 3.

  Each support portion 32 includes a casing 33 provided at the tip end portion of the guide spoke 31 of the first cutter spoke 13 and bearings 36 and 37 which are accommodated in the casing 33 and support pins 35 of a beam cutter main body 34 which will be described later. , 38 and a seal mechanism 39 for preventing dirt and sand from entering the casing 33.

  The shield machine 1 includes a beam cutter 4 for excavating a natural ground that is radially outward from the outer peripheral edge of the rotary cutter 3. The beam cutter 4 has a beam cutter main body 34 formed in a beam shape. The beam cutter main body 34 is rotatably supported by the support portion 32 of each first cutter pork 13 at a portion on the inner side in the longitudinal direction from both ends in the longitudinal direction. In the present embodiment, a pin 35 is provided at a portion on the inner side in the longitudinal direction with respect to both ends in the longitudinal direction of the beam cutter main body 34, and the beam cutter main body 34 supports the first cutter pork 13 by this pin 35. The part 32 is rotatably supported.

  Two hydraulic jacks (first and second hydraulic jacks) 40a, 40b as actuators for moving each support portion 32 along the longitudinal direction of each first cutter pork 13, that is, the radial direction of the rotary cutter 3, are provided. Provided. As shown in FIGS. 3 and 5, the first and second hydraulic jacks 40 a and 40 b are respectively a cylinder tube 41 attached to the guide spoke 31, and a disk-shaped head 41 h ( 6), a disc-shaped cap 41c (see FIG. 6) attached to the other end of the cylinder tube 41, and a slidable member in the axial direction in the cylinder tube 41. It has a piston 44 (see FIG. 6) that partitions the cap-side hydraulic chamber 43, and a rod 45 that has one end connected to the piston 44 and the other end connected to the center member 12. That is, the first and second hydraulic jacks 40 a and 40 b are arranged on the cutter frame 8 of the rotary cutter 3 so as to be at a predetermined angle along the radial direction of the cutter frame 8 and in the circumferential direction of the cutter frame 8. Yes.

  As shown in FIG. 6, hydraulic circuits 46 for operating the first and second hydraulic jacks 40a and 40b are connected to the first and second hydraulic jacks 40a and 40b, respectively. Head side hydraulic supply lines 47 connecting the head side hydraulic chambers 42 of the first and second hydraulic jacks 40a, 40b and the hydraulic circuit 46 are respectively connected to the head side hydraulic chambers 42 of the first and second hydraulic jacks 40a, 40b. Head side first and second control valves 48a and 48b for controlling the amount of oil to be supplied are provided. Cap side hydraulic supply lines 49 connecting the cap side hydraulic chambers 43 of the first and second hydraulic jacks 40a, 40b and the hydraulic circuit 46 are respectively provided with cap side hydraulic chambers of the first and second hydraulic jacks 40a, 40b. Cap-side first and second control valves 50 a and 50 b for controlling the amount of oil supplied to 43 are provided. In the present embodiment, servo valves are used as the first and second control valves 48a and 48b on the head side and the first and second control valves 50a and 50b on the cap side.

  When the support portions 32 are moved outward in the radial direction of the rotary cutter 3, the hydraulic circuit 46, the first and second control valves 48a and 48b on the head side, and the first and second control valves 50a and 50b on the cap side. Is operated to the extension side to extend the first and second hydraulic jacks 40a, 40b. On the other hand, when the support portions 32 are moved radially inward of the rotary cutter 3, the hydraulic circuit 46, the first and second control valves 48a and 48b on the head side, and the first and second control valves 50a on the cap side. , 50b are operated to the contraction side, and the first and second hydraulic jacks 40a, 40b are contracted.

  As shown in FIGS. 1 and 4, a plurality of cutter bits 51 are arranged on the front surfaces of both ends in the longitudinal direction of the beam cutter main body 34. These cutter bits 51 are arranged slightly behind the cutter bit 10 of the rotary cutter 3 in the digging direction. That is, in the state where both longitudinal ends of the beam cutter main body 34 are located radially inward from the outer peripheral edge of the rotary cutter 3, the longitudinal end portions (the cutter bit 51) of the beam cutter main body 34 are in contact with the ground. Instead, the excavated sediment in the chamber 6 is only stirred. Further, in a state where one longitudinal end portion of the beam cutter body 34 protrudes radially outward from the outer peripheral edge of the rotary cutter 3, the longitudinal end portion (cutter bit 51) of the beam cutter main body 34 is the outer peripheral edge of the rotary cutter 3. The other end in the longitudinal direction (cutter bit 51) of the beam cutter main body 34 is not in contact with the natural ground, and the excavated earth and sand in the chamber 6 is not contacted with the natural ground. Just stir.

  The shield machine 1 includes a controller 52 as a control means for causing the first and second hydraulic jacks 40 a and 40 b to project one end in the longitudinal direction of the beam cutter body 34 radially outward from the outer peripheral edge of the rotary cutter 3. (See FIG. 6). The controller 52 controls the opening degrees of the first and second control valves 48a and 48b on the head side and the first and second control valves 50a and 50b on the cap side, respectively.

  When projecting one end in the longitudinal direction of the beam cutter body 34 radially outward from the outer peripheral edge of the rotary cutter 3, one of the two first cutter spokes 13 adjacent to each other in the circumferential direction of the rotary cutter 3 is used. By moving one support portion 32 provided on the first cutter pork 13 radially outward of the rotary cutter 3, one longitudinal end of the beam cutter body 34 is moved radially outward of the rotary cutter 3. By moving the other support portion 32 provided on the other first cutter pork 13 to the inside in the radial direction of the rotary cutter 3, one end portion in the longitudinal direction of the beam cutter body 34 rotates around the one support portion 32. The cutter 3 is rotated outward in the radial direction.

  The controller 52 is connected to a rotation angle sensor 53 as rotation angle detection means for detecting the rotation angle of the rotary cutter 3 (cutter frame 8) (see FIG. 7). The controller 52 is connected with first and second stroke sensors 54a and 54b as first and second stroke detecting means for detecting the strokes of the first and second hydraulic jacks 40a and 40b, respectively. (See FIGS. 6 and 7).

  The controller 52 includes first and second hydraulic sensors 55a and 55b on the head side as first and second hydraulic pressure detecting means for detecting the head hydraulic pressures of the first and second hydraulic jacks 40a and 40b. They are connected (see FIGS. 6 and 8). The controller 52 includes cap-side first and second hydraulic sensors 56a and 56b as first and second hydraulic pressure detecting means for detecting cap-side hydraulic pressures of the first and second hydraulic jacks 40a and 40b. They are connected (see FIGS. 6 and 8).

  Hereinafter, control of the first and second hydraulic jacks 40a and 40b by the controller 52 will be described with reference to FIGS.

  Here, in the present embodiment, the hydraulic jack having a large stroke change when the cutter frame 8 rotates once is set as the first hydraulic jack 40a, and the stroke change occurs when the cutter frame 8 rotates once. Assume that the small hydraulic jack is the second hydraulic jack 40b, and the controller 52 controls the stroke of the hydraulic jack. Specifically, in the present embodiment, of the two hydraulic jacks, the hydraulic jack located on the front side in the rotational direction of the cutter frame 8 is referred to as the first hydraulic jack 40a, and the hydraulic jack located on the rear side in the rotational direction of the cutter frame 8 is the first. A dual hydraulic jack 40b is used.

  First, the stroke control of the first hydraulic jack 40a will be described.

  As shown in FIG. 7, the controller 52 inputs the rotation angle of the rotary cutter 3 detected by the rotation angle sensor 53 to the lookup table 57a and determines the stroke setting value of the first hydraulic jack 40a. In the lookup table 57a, the stroke setting value of the first hydraulic jack 40a corresponding to the rotation angle of the rotary cutter 3 is obtained and inputted in advance, and the rotation angle of the rotary cutter 3 is input to the lookup table 57a. Thus, the stroke set value of the first hydraulic jack 40a is obtained.

  Next, the controller 52 obtains a stroke deviation between the stroke setting value of the first hydraulic jack 40a and the stroke detection value of the first hydraulic jack 40a detected by the first stroke sensor 54a (stroke deviation = stroke setting value−stroke). Detection value), the opening degree of the first control valve 48a on the head side, the opening degree of the first control valve 50a on the cap side, and the like such that the stroke deviation becomes zero (P control or PI control).

  The controller 52 controls the first control valves 48a and 50a according to the determined opening degree and adjusts the amount of oil supplied to the first hydraulic jack 40a, thereby reducing the stroke of the first hydraulic jack 40a. Control to be a predetermined value.

  Next, stroke control of the second hydraulic jack 40b will be described.

  As shown in FIG. 8, the controller 52 inputs the rotation angle of the rotary cutter 3 detected by the rotation angle sensor 53 to the lookup table 57b and determines the stroke setting value of the second hydraulic jack 40b. In the lookup table 57b, the stroke setting value of the second hydraulic jack 40b corresponding to the rotation angle of the rotary cutter 3 is obtained and inputted in advance, and the rotation angle of the rotary cutter 3 is input to the lookup table 57b. Thus, the stroke set value of the second hydraulic jack 40b is obtained.

  Next, the controller 52 obtains a stroke deviation between the stroke setting value of the second hydraulic jack 40b and the stroke detection value of the second hydraulic jack 40b detected by the second stroke sensor 54b (stroke deviation = stroke setting value−stroke). Detection value), the jack thrust setting value of the second hydraulic jack 40b is determined such that the stroke deviation becomes zero (P control or PI control).

  Here, in the present specification, the jack thrust is a value obtained by subtracting a pulling force (pulling force) for reducing the hydraulic jack from a pressing force (pressing force) for extending the hydraulic jack, When the value is positive, it represents a pushing force, and when it is negative, it represents a pulling force.

  The controller 52 obtains a pressing force based on the head-side hydraulic pressure detected by the head-side second hydraulic pressure sensor 55b and the head sectional area (Sh) (pressing force = head-side hydraulic pressure × head sectional area), Based on the cap-side oil pressure detected by the cap-side second hydraulic sensor 56b and the cap cross-sectional area (Sc), the pulling force is obtained (attraction force = cap-side oil pressure × cap cross-sectional area), and the obtained pushing force and pulling force are obtained. Based on the above, a jack thrust calculation value is obtained (jack thrust calculation value = pushing force−pulling force).

  Next, the controller 52 obtains a jack thrust deviation between the determined jack thrust setting value and the jack thrust calculation value (jack thrust deviation = jack thrust setting value−jack thrust calculation value), so that the jack thrust deviation becomes zero. The opening degree of the second control valve 48b on the head side, the opening degree of the second control valve 50b on the cap side, and the like are determined (P control or PI control).

  The controller 52 controls the second control valves 48b and 50b according to the determined opening degree and adjusts the amount of oil supplied to the second hydraulic jack 40b, thereby reducing the stroke of the second hydraulic jack 40b. Control to be a predetermined value.

  When excavating the natural ground, as shown in FIG. 12, when the rotary cutter 3 is driven to rotate by the drive motor 23, the natural ground is excavated into a circular cross section by the rotary cutter 3 to form a circular cross section hole. Is done.

  Further, as shown in FIGS. 12 to 14, if one end in the longitudinal direction of the beam cutter main body 34 protrudes radially outward from the outer peripheral edge of the rotary cutter 3 according to the rotation angle of the rotary cutter 3, the rotary cutter 3 The ground of the unexcavated region radially outside the outer peripheral edge of the hole of the circular section formed by 3 is excavated by the beam cutter 4 (cutter bit 51), and the horseshoe-shaped section continuous with the hole of the circular section A hole is formed.

  By the way, when both the first and second hydraulic jacks 40a and 40b are controlled by controlling the stroke deviation (stroke) (referred to as “stroke-stroke control”), the target stroke to which the stroke of the first hydraulic jack 40a is given. If the stroke of the second hydraulic jack 40b slightly deviates from the target stroke when following the above, the second hydraulic jack 40b tries to follow the target stroke with a larger jack thrust. Since the stroke of the first hydraulic jack 40a is shifted from the target stroke by adjusting the stroke of the second hydraulic jack 40b to the target stroke, the first hydraulic jack 40a attempts to follow the target stroke with a larger jack thrust. By repeating such a flow by the two hydraulic jacks 40a and 40b, the thrust of the hydraulic jacks 40a and 40b increases, and consequently, the twisting force in the direction perpendicular to the jack thrust of the hydraulic jacks 40a and 40b increases. There is a possibility of going.

  As in the present embodiment, the first hydraulic jack 40a is controlled with the stroke deviation (stroke) as the control target, and the second hydraulic jack 40b is controlled with the jack thrust deviation (hydraulic pressure) as the control target ("stroke-hydraulic pressure"). In this case, the maximum value of the twisting force of the first and second hydraulic jacks 40a and 40b can be controlled by controlling the jack thrust of the second hydraulic jack 40b.

Hereinafter, a calculation method of the twisting force and a control method of the twisting force will be described with reference to FIG.
[Method of calculating the twisting force]
Each force acting on the beam cutter 4 is defined as follows.

H1, H2: Jack thrust force of the first and second hydraulic jacks V1, V2: Prying force of the first and second hydraulic jacks Rh1, Rh2: A component horizontal to the beam cutter body of the resultant force of H1, V1 (H2, V2) R1, R2: Components perpendicular to the beam cutter body of the resultant force of H1, V1 (H2, V2) Fφ: Force that the cutter bit tip receives from the ground
Fφx: a component that is horizontal to the beam cutter body of Fφ Fφy: a component that is perpendicular to the beam cutter body of Fφ V1 and V2 define the direction inside the longitudinal direction of the beam cutter body 34 as the plus direction (positive direction).

  As shown in FIG. 9, the excavation force Fφ is a point load in a direction perpendicular to a line L (excavation radius) connecting the cutter center O and the tip T of the cutter bit 51 with respect to the tip T of the cutter bit 51. Model as acting. If the excavation radius is not changed during excavation, the force in the excavation radius direction can be ignored.

  The greatest force acting on the beam cutter 4 is the digging force Fφ, and other forces (gravity, inertial force, etc.) are smaller than the digging force Fφ and can be ignored, and the balance of forces is considered.

  The forces (H1, H2, V1, V2) in the hydraulic jack coordinate system (local coordinate system) and the forces (Rh1, Rh2, R1, R2) in the beam cutter body coordinate system (overall coordinate system) are as follows: Can be transformed into

  From the force balance formula in the x direction,

  From the balance formula of force in the y direction,

  From formula (3) / formula (4),

  From equations (2) and (5),

  From the moment balance formula,

  Solving equations (6) and (7) for V1 and V2,

  Here, θf, δf, θ′f, δ′f, and γF are determined by the rotation angle Ψ of the rotary cutter 3 when the excavation radius is determined. l1 and l2 are constants. Therefore, aij in equation (9) is determined by the rotation angle Ψ of the rotary cutter 3.

If H1 and H2 are not determined, V1 and V2 cannot be obtained using equation (9). Therefore, unit force 1 is given as H1, and H2 is given as a ratio to H1. Therefore, if H2 is determined, V1 and V2 can be obtained from equation (9).
[Method of controlling twisting force]
The purpose of controlling the second hydraulic jack 40b with the jack thrust H2 as a control target is to set the maximum value (max {| V1 |, | V2) of the absolute values of the twisting forces V1, V2 of the first and second hydraulic jacks 40a, 40b. The value of |} is minimized.

  The relationship between the jack thrust H2 of the second hydraulic jack 40b and the twisting forces V1 and V2 of the first and second hydraulic jacks 40a and 40b was confirmed by changing the rotation angle of the rotary cutter 3 by simulation (see FIG. 10). ).

  As a result of the simulation, it was found that the twisting forces V1 and V2 can be minimized when V1 + V2 = 0 (| V1 | = | V2 |) regardless of the rotation angle Ψ of the rotary cutter 3.

  Therefore, in the present embodiment, the second value is set so that “V1 + V2 = 0” is satisfied, that is, the sum of the bending force V1 of the first hydraulic jack 40a and the bending force V2 of the second hydraulic jack 40b is zero. It is assumed that the jack thrust H2 of the hydraulic jack 40b is controlled (referred to as “twisting force reduction control”).

  Hereinafter, the twisting force reduction control by the second hydraulic jack 40b will be described.

  The controller 52 calculates the jack thrust calculation value of the second hydraulic jack 40b obtained from the detected values of the second hydraulic sensors 55b and 56b, the head sectional area (Sh) and the cap side sectional area (Sc) as H2, ) To determine the calculated value (V1) of the first hydraulic jack 40a and the calculated value (V2) of the second hydraulic jack 40b.

  Next, the controller 52 determines a larger value (max {| V1) of the absolute value of the calculated value (V1) of the first hydraulic jack 40a and the calculated value (V2) of the second hydraulic jack 40b. |, | V2 |}) is minimized, and the sum of the calculated value (V1) of the first hydraulic jack 40a and the calculated value (V2) of the second hydraulic jack 40b is zero (V1 + V2 = 0). ) To determine the jack thrust set value of the second hydraulic jack 40b.

  Next, the controller 52 obtains a jack thrust deviation between the determined jack thrust set value of the second hydraulic jack 40b and the jack thrust calculated value of the second hydraulic jack 40b (jack thrust thrust deviation = jack thrust set value−jack thrust calculated value). ), The opening degree of the second control valve 48b on the head side, the opening degree of the second control valve 50b on the cap side, etc., such that the jack thrust deviation becomes zero (P control or PI control).

  Then, the controller 52 controls the second control valves 48b and 50b according to the determined opening degree or the like, and adjusts the amount of oil supplied to the second hydraulic jack 40b.

  By actual machine experiments, it is possible to reduce the squeezing force (V1) of the first hydraulic jack 40a and the squeezing force (V2) of the second hydraulic jack 40b as compared with “stroke-stroke control” (see FIG. 11A). It confirmed (refer FIG.11 (b)).

  In the present embodiment, the controller 52 executes the twisting force reduction control when it is determined that “the twisting forces V1 and V2 need to be reduced”.

  First, using equations (1) to (3), Fφx and Fφy are obtained, and Fφ is obtained as absolute values thereof. The obtained Fφ is set as a calculated excavation force (Fφ) that the tip of the cutter bit 51 (beam cutter main body 34) receives from the natural ground.

  In the present embodiment, as shown in FIG. 8, the controller 52 has the calculated excavation force value (Fφ) larger than a predetermined threshold value (Fφ_th) (Fφ> Fφ_th) and is detected by the rotation angle sensor 53. The second hydraulic jack 40b obtained from the stroke setting value of the second hydraulic jack 40b determined based on the rotation angle of the rotary cutter 3 and the stroke detection value of the second hydraulic jack 40b detected by the second stroke sensor 54b. When the stroke deviation (Perr) is smaller than a predetermined threshold value (Perr_th) (Perr <Perr_th), it is determined that “needing forces V1 and V2 need to be reduced”, and the twisting force reduction control is executed. It has become.

  In this way, when the second hydraulic jack 40b is controlled (hydraulic control) using the jack thrust deviation (hydraulic pressure) as a control target, and the first and second hydraulic jacks 40a and 40b have large squeezing forces V1 and V2, By controlling the hydraulic pressure of the second hydraulic jack 40b so that the forces V1 and V2 are minimized, the hydraulic jacks 40a and 40b can be prevented from being damaged.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various other embodiments can be adopted.

  For example, in the above-described embodiment, the controller 52 executes the twisting force reduction control when it is determined that “the twisting forces V1 and V2 need to be reduced”. However, the present invention is not limited to this. Since the magnitudes of the prying forces V1 and V2 basically depend on the rotation angle of the rotary cutter 3, that is, the excavation cross section (excavation radius), the controller 52 performs the excavation when the predetermined rotation angle is reached. Force reduction control may be executed.

It is a front view of the shield machine which concerns on one Embodiment of this invention. It is the II-II sectional view taken on the line of FIG. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 1. FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 1. FIG. 5 is a cross-sectional view taken along line VV in FIG. 2. It is the schematic of a hydraulic jack. It is a block diagram which shows control (stroke control) of the hydraulic jack by a control means. It is a block diagram which shows control (hydraulic control) of the hydraulic jack by a control means. It is the schematic for demonstrating each force which acts on a beam cutter. (A)-(c) is a graph which shows the relationship between the jack thrust of a 2nd jack, and the prying force of a 1st and 2nd hydraulic jack. (A) And (b) is a graph which shows the relationship between the rotation angle of a rotary cutter, and the prying force of a 1st and 2nd hydraulic jack. It is a front view of the shield machine which excavates a horseshoe-shaped cross section. It is a front view of the shield machine which excavates a horseshoe-shaped cross section. It is a front view of the shield machine which excavates a horseshoe-shaped cross section.

Explanation of symbols

1 Shield machine 2 Shield body 4 Beam cutter 8 Cutter frame 40a Hydraulic jack (first hydraulic jack)
40b Hydraulic jack (second hydraulic jack)
48a Control valve (first control valve on the head side)
48b Control valve (head side second control valve)
50a Control valve (cap side first control valve)
50b Control valve (second control valve on the cap side)
52 Controller (Control means)
53 Rotation angle sensor (Rotation angle detection means)
54a Stroke sensor (first stroke detection means)
55b Oil pressure sensor (head side second oil pressure detecting means)
56b Oil pressure sensor (second oil pressure detecting means on the cap side)

Claims (1)

A cutter frame rotatably provided at the front portion of the shield body, and first and second hydraulic pressures disposed along the radial direction of the cutter frame and at a predetermined angle in the circumferential direction of the cutter frame. Shield drilling comprising a jack and a beam cutter formed in the shape of a beam and having a portion on the inner side in the longitudinal direction of the longitudinal end of the jack rotatably supported by the extendable ends of the first and second hydraulic jacks In the machine
Rotation angle detection means for detecting the rotation angle of the cutter frame, first stroke detection means for detecting the stroke of the first hydraulic jack, and second pressure for detecting the hydraulic pressure of the second hydraulic jack. Oil pressure detection means, first and second control valves for controlling the amounts of oil supplied to the first and second hydraulic jacks, respectively, and control means for controlling the opening degrees of the first and second control valves; With
The control means includes
The stroke setting value of the first hydraulic jack is determined based on the rotation angle detected by the rotation angle detection means, and the stroke setting value and the stroke detection value of the first hydraulic jack detected by the first stroke detection means are determined. And controlling the opening degree of the first control valve so that the deviation from is zero,
The jack thrust calculation value of the second hydraulic jack is determined based on the hydraulic pressure detection value of the second hydraulic jack detected by the second hydraulic pressure detection means, and the jack thrust calculation value and the rotation angle detection means detect the jack pressure calculation value. Determine the calculated value of the twisting force in the direction orthogonal to the jack thrust of the first hydraulic jack and the calculated value of the twisting force in the direction orthogonal to the jack thrust of the second hydraulic jack determined according to the rotation angle, respectively. The jack thrust setting value of the second hydraulic jack is determined so that the sum of the calculated value of the jacking force of the hydraulic jack and the calculated value of the twisting force of the second hydraulic jack becomes zero. A shield machine that controls the opening degree of the second control valve so that a deviation from a jack thrust calculation value of a hydraulic jack becomes zero.

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