Patent Description:
Regarding a tunnel boring machine, the wear amount of a disc cutter mounted on a cutterhead is measured regularly. Known has been a technique of showing the condition of the leading end portion of a tunnel boring machine on an image display device by use of an image sensor (for example, refer to Patent Literature <NUM>). As a technique of measuring the shape of an object in a noncontact manner, known has been a three-dimensional shape measurement device.

Patent Literature <NUM>: <CIT> <CIT> discloses a tunnel boring machine with disc cutters having a cutter ring and a wear amount detector which is provided as an electromagnetic wave detector or as a laser detector.

<CIT> and <CIT> disclose disc cutters that have a sensor for detecting the worn state of the cutter.

<CIT> discloses a tunnel boring machine including disc cutter with a wear detection device for the disc cutter. The wear detection device comprises a semiconductor laser, a CCD camera and a cemented carbide chip embedded in the top portion of a cutter ring.

In a case where the wear amount of a disc cutter is measured with a three-dimensional shape measurement device, for example, three-dimensional data of the disc cutter in the criterial state, such as just after attachment or before operation, and three-dimensional data of the disc cutter in an operation state are superimposed together on the basis of features of the shape of the disc cutter, and then the wear amount is measured. However, a change in the shape of the disc cutter due to wearing is likely to cause a larger error in superimposition of such pieces of three-dimensional data.

An object of the present invention is to achieve highly accurate measurement of the wear amount of a disc cutter.

According to an aspect of the present invention, a tunnel boring machine comprises: a disc cutter including a cutter ring; and a member for use in measurement of a wear amount of the cutter ring, wherein the wear amount of the cutter ring is measured with a three-dimensional shape measurement device, wherein the member is provided at a part constant in relative position to the cutter ring and wherein the member is provided on each of one side and another side in an axial direction of the cutter ring. Advantageous Effects of Invention.

According to the present invention, highly accurate measurement of the wear amount of a disc cutter can be achieved.

However, the present invention is not limited to the embodiments. The constituent elements in the following embodiments can be appropriately combined. In some cases, some of the constituent elements are not necessarily used. The scope of the invention is nevertheless defined by the independent claims with further examples defined by the dependent claims.

<FIG> is a side view of the configuration of a tunnel boring machine <NUM> according to the present embodiment. <FIG> is a schematic perspective view of a cutterhead <NUM> of the tunnel boring machine <NUM> according to the present embodiment. For example, the tunnel boring machine <NUM> excavates rock in construction of an underground structure, such as a tunnel or a system for supplying water. The tunnel boring machine <NUM> includes a main body <NUM> and the cutterhead <NUM> that is provided on the front side of the main body <NUM> and excavates rock. As illustrated in <FIG> and <FIG>, the cutterhead <NUM> is domed in shape and internally has a cutter chamber 30C serving as a space for taking in excavated muck generated due to excavation.

The main body <NUM> includes a main beam <NUM> extending in the front-and-back direction and a cutterhead support <NUM> provided at the front end of the main beam <NUM>. The cutterhead <NUM> is coupled rotatably to the cutterhead support <NUM> through a bearing <NUM>. The cutterhead support <NUM> of the main body <NUM> has an upper portion provided with a roof support <NUM>, side portions each provided with a side support <NUM>, and a lower portion provided with a vertical support <NUM>. As illustrated in <FIG>, the roof support <NUM>, the side supports <NUM>, and the vertical support <NUM> are provided in a cylindrical shape such that the respective outer circumferences thereof are along the sectional shape for excavation.

Inside the main body <NUM>, provided are a gripper <NUM> to be pressed against the wall of a tunnel and a thrust jack <NUM> variable in length along the main beam <NUM>. The end portion on the front side in the axial direction of the thrust jack <NUM> is attached on the front side of the main beam <NUM> and the end portion on the back side thereof is attached to the gripper <NUM>. The thrust jack <NUM> is provided variably in length in the front-and-back direction. The tunnel boring machine <NUM> generates a thrust force with a variation in the length of the thrust jack <NUM>. The tunnel boring machine <NUM> presses the gripper <NUM> against the wall of the tunnel, to acquire a thrust reaction force.

Inside the main body <NUM>, provided are a belt conveyor <NUM> extending in the front-and-back direction, a chute hopper <NUM> provided at the upper portion on the front side of the belt conveyor <NUM>, the cutterhead support <NUM> provided at the end portion on the front side of the main beam <NUM>, and a drive motor <NUM>. The belt conveyor <NUM> conveys excavated muck generated due to excavation, backward. The belt conveyor <NUM> is provided inside the main beam <NUM> tubular in shape and penetrates through the cutterhead support <NUM> such that the leading end thereof is located in the cutter chamber 30C. The chute hopper <NUM> is open in the cutter chamber 30C and guides, to the belt conveyor <NUM>, excavated muck scooped in by buckets <NUM> of the cutterhead <NUM>. The cutterhead support <NUM> supports the cutterhead <NUM> rotatably around the rotation axis AX1 thereof. The cutterhead support <NUM> is provided with the drive motor <NUM> for rotating the cutterhead <NUM>. The drive motor <NUM> serves as a hydraulic motor or an electric motor.

The cutterhead support <NUM> to which the cutterhead <NUM> is connected through the bearing <NUM> is provided with the drive motor <NUM>. The cutterhead <NUM> rotates around the rotation axis AX1 due to the drive motor <NUM>. Due to a variation in the length of the thrust jack <NUM>, the cutterhead <NUM> moves in the front-and-back direction with respect to the gripper <NUM>. The cutterhead <NUM> has a plurality of disc cutters <NUM> mounted thereon. The cutterhead <NUM> is provided ahead of the main body <NUM>. The cutterhead <NUM> is provided with a plurality of cylindrical cases <NUM> each housing and retaining a disc cutter <NUM>. That is, the cases <NUM> provided at the cutterhead <NUM> are identical in position to the disc cutters <NUM> provided at the cutterhead <NUM>.

A disc cutter <NUM> will be described with <FIG> and <FIG>. <FIG> is a side view of the disc cutter <NUM>. <FIG> is the front view of the disc cutter <NUM>. The disc cutter <NUM> is supported rotatably to the cutterhead <NUM>. The disc cutter <NUM> is provided at the cutterhead <NUM> such that the rotation axis thereof (fixed axis AX2 to be described below) intersects with the rotation axis AX1 of the cutterhead <NUM>. The disc cutter <NUM> rotates as the disc cutter <NUM> is pressed against the excavation face of the tunnel, so that the rock is crushed. More particularly, with the cutterhead <NUM> rotating, application of a forward thrust force to the main body <NUM> and the cutterhead <NUM> causes the disc cutter <NUM> to rotate in contact with the rock under pressure. Rotation of the disc cutter <NUM> in contact with the rock under pressure causes rock crushing and rock cracking at the contact between a blade edge <NUM> of the disc cutter <NUM> and the rock. A crack occurring in the rock links with another crack adjacent thereto and then adjacent crushing occurs, resulting in excavation of the rock. Excavated muck generated in excavation of the rock is scooped in the chute hopper <NUM> open in the cutter chamber 30C through the buckets <NUM> provided at the cutterhead <NUM> and then is conveyed backward by a belt conveyor <NUM>.

The disc cutter <NUM> includes a cutter ring <NUM>, a hub <NUM> supporting the cutter ring <NUM> unrotatably, a shaft (not illustrated) supporting the hub <NUM> rotatably through a bearing (not illustrated), and a pair of retainers <NUM> retaining the shaft with the hub <NUM> interposed therebetween in the axial direction. The central line of the shaft retained by the pair of retainers <NUM> is illustrated as the fixed axis AX2 in <FIG>. That is, the cutter ring <NUM> and the hub <NUM> are supported rotatably through the bearing not illustrated on the fixed axis AX2. The cutter ring <NUM> and the hub <NUM> are rotatable integrally. The pair of retainers <NUM> serves as a retaining member that sandwiches the cutter ring in the axial direction and retains the cutter ring rotatably. The cutter ring <NUM> rotates as the cutter ring <NUM> is pressed against the excavation face of the tunnel, so that the excavation face is excavated.

The cutter ring <NUM> has a blade edge <NUM>. The blade edge <NUM> protrudes forward and backward from the case <NUM> (refer to <FIG> and <FIG>). The blade edge <NUM> is exposed from the front face and back face of the case <NUM>. The blade edge <NUM> protrudes forward from the front face <NUM> of the cutterhead <NUM>.

As illustrated in <FIG> and <FIG>, the disc cutter <NUM> is detachably housed in the case <NUM> provided at the cutterhead <NUM>. Inside the case <NUM>, provided is a bearing face that receives the press reaction force of the cutter ring <NUM> to the excavation face. The pair of retainers <NUM> of the disc cutter <NUM> is fixed to the bearing face. Key blocks <NUM> are used for positioning of the disc cutter <NUM> to the case <NUM>, namely, for positioning of the disc cutter <NUM> to the cutterhead <NUM>. The key blocks <NUM> are each detachably provided, from the cutter chamber side, to the case <NUM>. As illustrated in <FIG>, with the disc cutter <NUM> having the retainers <NUM> abutting on the bearing face of the case <NUM>, the key blocks <NUM> are provided from the cutter chamber side. Each key block <NUM> and the corresponding retainer <NUM> are fastened through the case <NUM> with bolts <NUM>, so that the disc cutter <NUM> is fixed to the cutterhead <NUM>. As described above, the bearing face of the case <NUM> functions to support the press reaction force of the disc cutter <NUM> to the excavation face, and the key blocks <NUM> in cooperation with the bolts <NUM> function as a positioning member that positions the disc cutter <NUM> to the cutterhead <NUM> and restricts movement thereof.

A method of replacing a disc cutter <NUM> will be described in detail with <FIG> is a schematic explanatory view of detachment of the disc cutter <NUM>. The disc cutter <NUM> is restricted by the key blocks <NUM> in detachment from the case <NUM> and in movement along the circumferential direction of the case <NUM>. As illustrated in <FIG>, the bolts <NUM> fixing the key blocks <NUM> to the case <NUM> are detached. As illustrated in <FIG>, the key blocks <NUM> are detached from the case <NUM>. The detachment of the key blocks <NUM> releases the restriction of the disc cutter <NUM>. As illustrated in <FIG>, the disc cutter <NUM> housed in the case <NUM> is rotated by <NUM>° in the circumferential direction of the case <NUM>. As illustrated in <FIG>, the disc cutter <NUM> is detached from the case <NUM>.

In a case where a new disc cutter <NUM> is housed into the case <NUM>, the disc cutter <NUM> is inserted into the case <NUM>, inversely to the process in <FIG>. Inversely to the process in <FIG>, the disc cutter <NUM> inserted in the case <NUM> is rotated by <NUM>°, inversely to the rotation in detachment, in the circumferential direction of the case <NUM>. Inversely to the process in <FIG>, the key blocks <NUM> are attached to the case <NUM>. Inversely to the process in <FIG>, the key blocks <NUM> are fixed to the case <NUM> with the bolts <NUM>. In this manner, fixed is the disc cutter <NUM> restricted by the key blocks <NUM> in detachment from the case <NUM> and in movement along the circumferential direction of the case <NUM>.

An excavation method by such a tunnel boring machine <NUM> as above will be described. In the tunnel boring machine <NUM>, due to the drive motor <NUM>, the cutterhead <NUM> rotates with respect to the main body <NUM>. Each disc cutter <NUM> attached to the cutterhead <NUM> rotates as each disc cutter <NUM> is pressed against the excavation face of the tunnel, so that the rock is crushed. Excavated muck produced in excavation of the rock is scooped into the main body <NUM> by the buckets <NUM> and then is conveyed backward by the belt conveyor <NUM>. Because each disc cutter <NUM> wears due to excavation, for example, before the start of daily work or every predetermined period, the wear amount of the cutter ring <NUM> of each disc cutter <NUM> is measured.

A measurement device <NUM> for use in measurement of the wear amount of the cutter ring <NUM> of a disc cutter <NUM>, in the tunnel boring machine <NUM>, will be described with <FIG> is a schematic view of the configuration of the measurement device <NUM>. <FIG> is a schematic explanatory view of a state where the measurement device <NUM> measures a disc cutter <NUM>. The measurement device <NUM> is provided closer to the cutter chamber 30C (refer to <FIG>) in the tunnel boring machine <NUM>. The measurement device <NUM> includes a forward-and-backward variable slider <NUM> variable forward and backward in length, a front-and-back movement actuator <NUM> that slides a scanner <NUM> along the forward-and-backward variable slider <NUM>, an upward-and-downward variable slider <NUM> variable upward and downward in length, an up-and-down movement actuator <NUM> that slides the scanner <NUM> along the upward-and-downward variable slider <NUM>, the scanner <NUM>, and a case <NUM> that houses the forward-and-backward variable slider <NUM>, the front-and-back movement actuator <NUM>, the upward-and-downward variable slider <NUM>, the up-and-down movement actuator <NUM>, and the scanner <NUM>. The front-and-back movement actuator <NUM> varies the forward-and-backward variable slider <NUM> in length, to slide the scanner <NUM> forward and backward. The up-and-down movement actuator <NUM> varies the upward-and-downward variable slider <NUM> in length, to slide the scanner <NUM> upward and downward.

The scanner <NUM> serves as a 3D scanner, detects a target, and outputs three-dimensional data indicating the three-dimensional shape of the target to a data acquisition unit <NUM> in a measurement controller <NUM>. More particularly, the scanner <NUM> is capable of detecting the three-dimensional shape of the cutter ring <NUM> of a disc cutter <NUM> and a member <NUM> to be described below (refer to <FIG>). For example, the scanner <NUM> detects criterial three-dimensional data indicating the three-dimensional shape of a cutter ring <NUM> and a member <NUM> in the criterial state, such as just after attachment or before operation of a disc cutter <NUM> on which a new cutter ring <NUM> is mounted (namely, the cutter ring <NUM> has not worn yet) and measurement three-dimensional data indicating the three-dimensional shape of the cutter ring <NUM> and the member <NUM> in an operation state (namely, the cutter ring <NUM> is assumed to have worn to a certain extent). The scanner <NUM> outputs the detected criterial three-dimensional data and measurement three-dimensional data to the data acquisition unit <NUM> in the measurement controller <NUM>.

The scanner <NUM> is movable forward and backward by the forward-and-backward variable slider <NUM> and the front-and-back movement actuator <NUM> and is movable in the up-and-down direction by the upward-and-downward variable slider <NUM> and the up-and-down movement actuator <NUM>.

The scanner <NUM> adjustable in tilt angle is provided at the upward-and-downward variable slider <NUM>. The scanner <NUM> is capable of adjusting the angle of measurement to the cutter ring <NUM> of a disc cutter <NUM>. The angle of measurement corresponds to the angle between the central line C1 of the blade edge <NUM> of the cutter ring <NUM> and the central line C2 of the optical axis of the scanner <NUM>.

For example, the case <NUM> is provided at the cutterhead support <NUM>. With the measurement device <NUM> in non-measurement, the forward-and-backward variable slider <NUM>, the front-and-back movement actuator <NUM>, the upward-and-downward variable slider <NUM>, the up-and-down movement actuator <NUM>, and the scanner <NUM> are housed in the case <NUM>. In response to measurement of the measurement device <NUM>, the forward-and-backward variable slider <NUM>, the front-and-back movement actuator <NUM>, the upward-and-downward variable slider <NUM>, the up-and-down movement actuator <NUM>, and the scanner <NUM> are developed from the case <NUM>.

A controller <NUM> will be described with <FIG> is a block diagram of the configuration of the controller <NUM>. For example, the tunnel boring machine <NUM> is controlled by the controller <NUM>. For example, on the basis of operation information input through an operation board not illustrated or operating information input through an excavation management system not illustrated, the controller <NUM> actuates the tunnel boring machine <NUM>. A drive-motor control unit <NUM> in the controller <NUM> controls the drive motor <NUM> to rotate or stop rotating.

As illustrated in <FIG>, for example, the front-and-back movement actuator <NUM>, the up-and-down movement actuator <NUM>, and the scanner <NUM> in the measurement device <NUM> are controlled by the measurement controller <NUM>. A measurement target setting unit <NUM> in the measurement controller <NUM> controls the drive motor <NUM> to rotate the cutterhead <NUM> such that the scanner <NUM> can measure a disc cutter <NUM> as the measurement target. A front-and-back movement control unit <NUM> in the measurement controller <NUM> controls the front-and-back movement actuator <NUM> to adjust the position in the front-and-back direction of the scanner <NUM> on the basis of the disc cutter <NUM> as the measurement target. An up-and-down movement control unit <NUM> in the measurement controller <NUM> controls the up-and-down movement actuator <NUM> to adjust the position in the up-and-down direction of the scanner <NUM> on the basis of the disc cutter <NUM> as the measurement target. A scanner control unit <NUM> in the measurement controller <NUM> controls the scanner <NUM> to perform three-dimensional measurement. The data acquisition unit <NUM> in the measurement controller <NUM> acquires three-dimensional data from the scanner <NUM>. A wear-amount calculation unit <NUM> in the measurement controller <NUM> calculates the wear amount of the cutter ring <NUM> of the disc cutter <NUM>, on the basis of the acquired three-dimensional data.

A computer system <NUM> will be described with <FIG> is a block diagram of the computer system <NUM> according to the present embodiment. The controller <NUM> described above includes the computer system <NUM>. The computer system <NUM> includes a processor <NUM> like a central processing unit (CPU), a main memory <NUM> including a nonvolatile memory like a read only memory (ROM) and a volatile memory like a random access memory (RAM), a storage <NUM>, and an interface <NUM> including an input/output circuit. The function of the controller <NUM> and the function of the measurement controller <NUM>, described above, are stored as a program in the storage <NUM>. The processor <NUM> reads the program from the storage <NUM>, develops the program in the main memory <NUM>, and performs the processing described above, in accordance with the program. Note that the program may be distributed to the computer system <NUM> through a network.

A member <NUM> will be described with <FIG> and <FIG>. <FIG> is a front view of members <NUM> each provided at a key block by welding, in a first embodiment of the present invention. <FIG> is a side view of a case <NUM> on which a disc cutter <NUM> is mounted with the key blocks <NUM> each provided with the member <NUM>, in the first embodiment of the present invention. The members <NUM> are used in measurement of the wear amount of the cutter ring <NUM> of the disc cutter <NUM> with the three-dimensional shape measurement device (hereinafter, referred to as the "measurement device") <NUM>. More particularly, the members <NUM> are used in alignment in measurement with the measurement device <NUM>. The members <NUM> together with the cutter ring <NUM> are located detectably in the detection area of the measurement device <NUM>. Thus, in measurement with the measurement device <NUM>, the members <NUM> are detected together with the cutter ring <NUM>.

The members <NUM> are each located so as to be less likely to wear in excavation of the tunnel boring machine <NUM> and so as not to interfere with excavation and replacement of the disc cutter <NUM>. The members <NUM> are each provided at a part constant in relative position to the cutter ring <NUM> of the disc cutter <NUM>. The constant relative position means that the positional relationship between the cutter ring <NUM> and each member <NUM> does not vary between a state just after attachment or before operation of the disc cutter <NUM> and the state of the disc cutter <NUM> in operation. The members <NUM> are provided near the cutter ring <NUM>. In the present embodiment, the members <NUM> are provided at the key blocks <NUM> that restrict movement of the disc cutter <NUM> along the circumferential direction of the case <NUM>.

The members <NUM> are provided closer to the cutter chamber 30C in the tunnel boring machine <NUM>.

An exemplary shape of member <NUM> will be described with <FIG>. <FIG> is a front view of an exemplary member <NUM>. <FIG> is a side view of the member <NUM> illustrated in <FIG>. <FIG> is a plan view of the member <NUM> illustrated in <FIG>. The member <NUM> is formed of a combination of a wall <NUM>, a wall <NUM>, a wall <NUM>, a wall <NUM>, and a wall <NUM> planar in shape. The wall <NUM> is rectangular in shape. The wall <NUM> is provided in parallel to a surface 33a of a key block <NUM>. The wall <NUM> and the wall <NUM> are each trapezoidal in shape. The wall <NUM> and the wall <NUM> are each provided inclining at an intermediate portion of the wall <NUM>. The wall <NUM> and the wall <NUM> are each provided in a plane crossing the surface 33a of the key block <NUM>. A circumferential edge 52a of the wall <NUM> and a circumferential edge 53a of the wall <NUM> are each joined to the intermediate portion of the wall <NUM>, resulting in formation of bends. A circumferential edge 52b of the wall <NUM> and a circumferential edge 53b of the wall <NUM> are joined together, resulting in formation of a bend. The wall <NUM> and the wall <NUM> are each triangular in shape. The wall <NUM> is provided covering the opening surrounded by the upper portion of the wall <NUM>, the upper portion of the wall <NUM>, and the upper portion of the wall <NUM>. The wall <NUM> is provided covering the opening surrounded by the lower portion of the wall <NUM>, the lower portion of the wall <NUM>, and the lower portion of the wall <NUM>. The wall <NUM>, the wall <NUM>, the wall <NUM>, and the wall <NUM> each serve as part of formation of a humped shape protruding inward in the radial direction of the case <NUM> from a surface 33b of the key block <NUM>. The wall <NUM>, the wall <NUM>, the wall <NUM>, and the wall <NUM> each serve as part of formation of a triangular prism.

The respective normals of the wall <NUM>, the wall <NUM>, the wall <NUM>, the wall <NUM>, and the wall <NUM> extend in different directions and cross each other.

The wall <NUM> has a length d11 approximately the same as the width dk1 of the key block <NUM>. The wall <NUM> has a length d12 shorter than the distance dk2 from the key block <NUM> to the cutter ring <NUM>. The distance d13 from the wall <NUM> to the joint between the wall <NUM> and the wall <NUM> is approximately the same as the thickness dk3 of the key block <NUM> (refer to <FIG>). The wall <NUM> protrudes outward from the wall <NUM> and the wall <NUM>.

Preferably, such a plurality of members <NUM> as above is provided around a disc cutter <NUM>. In the present embodiment, two members <NUM> are provided around a disc cutter <NUM>.

Preferably, as in the present embodiment, one member <NUM> is provided on one side in the axial direction of a cutter ring <NUM> (direction of the fixed axis AX2) and another member <NUM> is provided on the other side.

In the present embodiment, such a member <NUM> is attached to a key block <NUM> by welding.

The member <NUM> has a plurality of faces facing in different directions. The plurality of faces of the member <NUM> varies mutually discontinuously.

The member <NUM> provided includes a humped shape protruding toward the cutter chamber 30C. In the present embodiment, the humped shape included in the member <NUM> protrudes from the surface 33b of the key block <NUM>.

Next, a method/processing of measuring the wear amount of the cutter ring <NUM> of a disc cutter <NUM> with the measurement device <NUM> in the tunnel boring machine <NUM> including disc cutters <NUM> will be described. <FIG> is a flowchart of an exemplary processing procedure of a method of measuring the cutter ring <NUM> of a disc cutter <NUM> in the criterial state. <FIG> is a flowchart of an exemplary processing procedure of a method of measuring the cutter ring <NUM> of a disc cutter <NUM> in an operation state. Before measurement of the wear amount of the cutter ring <NUM> of a disc cutter <NUM> in an operation state in the tunnel boring machine <NUM>, the processing illustrated in <FIG> is performed at least once, resulting in acquisition of criterial three-dimensional data of the disc cutter <NUM>. Such criterial three-dimensional data is preferably acquired in response to mounting of a new disc cutter <NUM> or mounting of a disc cutter <NUM> on which a new cutter ring is mounted.

The measurement target setting unit <NUM> in the measurement controller <NUM> sets a disc cutter <NUM> as the measurement target (Step S11). For example, the order of measurement of all disc cutters <NUM> mounted on the cutterhead <NUM> is stored in a storage unit not illustrated. In accordance with the stored order, the measurement target setting unit <NUM> sets the corresponding disc cutter <NUM> as the measurement target. The measurement target setting unit <NUM> in the measurement controller <NUM> controls the drive motor <NUM> to rotate the cutterhead <NUM> such that the scanner <NUM> can measure the disc cutter <NUM> as the measurement target. The measurement controller <NUM> proceeds to Step S12.

The measurement controller <NUM> moves the scanner <NUM> on the basis of the disc cutter <NUM> as the measurement target (Step S12). More particularly, the front-and-back movement control unit <NUM> in the measurement controller <NUM> controls the front-and-back movement actuator <NUM> to adjust the position in the front-and-back direction of the scanner <NUM> on the basis of the disc cutter <NUM> as the measurement target. The up-and-down movement control unit <NUM> in the measurement controller <NUM> controls the up-and-down movement actuator <NUM> to adjust the position in the up-and-down direction of the scanner <NUM> on the basis of the disc cutter <NUM> as the measurement target. The measurement controller <NUM> proceeds to Step S13.

The scanner control unit <NUM> in the measurement controller <NUM> controls the scanner <NUM> to perform three-dimensional measurement of the disc cutter <NUM> as the measurement target (Step S13). The scanner control unit <NUM> causes the scanner <NUM> to scan the three-dimensional shape of the disc cutter <NUM> as the measurement target. The scanner control unit <NUM> measures the three-dimensional shape of the cutter ring <NUM> in the criterial state together with the three-dimensional shape of the members <NUM>. The measurement controller <NUM> proceeds to Step S14.

The data acquisition unit <NUM> in the measurement controller <NUM> acquires data measured by the scanner <NUM> in the measurement device <NUM> (Step S14). The measurement controller <NUM> proceeds to Step S15.

The data acquisition unit <NUM> in the measurement controller <NUM> stores the acquired data as the criterial three-dimensional data of the disc cutter <NUM> into a storage unit <NUM> (Step S15). The criterial three-dimensional data of the disc cutter <NUM> includes three-dimensional shape data of the cutter ring <NUM> and three-dimensional shape data of the members <NUM> in the criterial state. The data acquisition unit <NUM> stores the acquired criterial three-dimensional data in association with identification information regarding the disc cutter <NUM> as the measurement target. The measurement controller <NUM> proceeds to Step S16.

The measurement controller <NUM> determines whether or not a disc cutter <NUM> as the next measurement target is present (Step S16). In a case where a disc cutter <NUM> yet to be measured is present, the measurement controller <NUM> determines that a disc cutter <NUM> as the next measurement target is present (Yes in Step S16), and then performs the processing in Step S11 again. In a case where all disc cutters <NUM> have been measured, the measurement controller <NUM> determines that no disc cutter <NUM> as the next measurement target is present (No in Step S16), and then terminates the processing.

In this manner, with the measurement device <NUM>, the measurement controller <NUM> acquires and stores the criterial three-dimensional data of the cutter ring <NUM> of each disc cutter <NUM> in the criterial state and the members <NUM> each provided at the part constant in relative position to the cutter ring <NUM>.

After acquisition of the criterial three-dimensional data, the processing illustrated in <FIG> is performed, for example, before the start of daily work or every predetermined period, resulting in measurement of the wear amount of the cutter ring <NUM> of each disc cutter <NUM> in the tunnel boring machine <NUM>. Step S21, Step S22, and Step S28 are similar in processing to Step S11, Step S12, and Step S16 described above, respectively, and thus the descriptions thereof will be omitted.

In Step S23, the scanner control unit <NUM> in the measurement controller <NUM> controls the scanner <NUM> to perform three-dimensional measurement of the disc cutter <NUM> as the measurement target. The scanner control unit <NUM> measures the three-dimensional shape of the cutter ring <NUM> in an operation state together with the three-dimensional shape of the members <NUM>. The measurement controller <NUM> proceeds to Step S24.

The data acquisition unit <NUM> in the measurement controller <NUM> acquires data measured by the scanner <NUM> in the measurement device <NUM> (Step S24). The measurement controller <NUM> proceeds to Step S25.

The data acquisition unit <NUM> in the measurement controller <NUM> stores the acquired data as the measurement three-dimensional data of the disc cutter <NUM> into the storage unit <NUM> (Step S25). The measurement three-dimensional data of the disc cutter <NUM> includes three-dimensional shape data of the cutter ring <NUM> and three-dimensional shape data of the members <NUM> in the operation state. The measurement controller <NUM> proceeds to Step S26.

The wear-amount calculation unit <NUM> in the measurement controller <NUM> reads the criterial three-dimensional data of the disc cutter <NUM> with reference to the identification information regarding the disc cutter <NUM>, and calculates the wear amount of the cutter ring <NUM> of the disc cutter <NUM>, on the basis of the criterial three-dimensional data and the measurement three-dimensional data (Step S26). The measurement controller <NUM> collates the criterial three-dimensional data and the measurement three-dimensional data, to calculate the wear amount of the cutter ring <NUM>. <FIG> is a schematic explanatory view of alignment in measurement. As illustrated in <FIG>, the wear-amount calculation unit <NUM> performs alignment between the criterial three-dimensional data indicated with broken lines and the measurement three-dimensional data indicated with solid lines, with respective members <NUM> as the criterion, namely, such that the respective members <NUM> are superimposed together. As illustrated in <FIG>, the difference between the blade edge <NUM> in the criterial three-dimensional data and the blade edge <NUM> in the measurement three-dimensional data after alignment corresponds to the wear amount W of the cutter ring <NUM>. The measurement controller <NUM> proceeds to Step S27.

The wear-amount calculation unit <NUM> in the measurement controller <NUM> stores, into the storage unit <NUM>, the calculated wear amount of the cutter ring <NUM> of the disc cutter <NUM> in association with the identification information regarding the disc cutter <NUM> (Step S27). The measurement controller <NUM> proceeds to Step S28.

In a case where a disc cutter <NUM> yet to be measured is present, the measurement controller <NUM> determines that a disc cutter <NUM> as the next measurement target is present (Yes in Step S28), and then performs the processing in Step S21 again. In a case where all disc cutters <NUM> have been measured, the measurement controller <NUM> determines that no disc cutter <NUM> as the next measurement target is present (No in Step S28), and then terminates the processing.

Due to such processing as above, the wear amount of the cutter ring <NUM> of each disc cutter <NUM> in the tunnel boring machine <NUM> in an operation state is calculated.

In the present embodiment, with a member <NUM> provided at a part constant in relative position to the cutter ring <NUM> of a disc cutter <NUM>, alignment is performed between the criterial three-dimensional data and the measurement three-dimensional data measured by the measurement device <NUM>. Because the member <NUM> is located so as not to wear, the member <NUM> is inhibited from varying in shape between the criterial three-dimensional data and the measurement three-dimensional data. According to the present embodiment, highly accurate alignment can be performed between the criterial three-dimensional data and the measurement three-dimensional data. In this manner, the present embodiment enables highly accurate measurement of the wear amount of the cutter ring <NUM>.

According to the present embodiment, alignment with the member <NUM> enables achievement of the targeted accuracy of measurement, regardless of the shape of the member <NUM>. According to the present embodiment, alignment with the member <NUM> enables achievement of the targeted accuracy of measurement, regardless of the wear amount of the cutter ring <NUM>. According to the present embodiment, alignment with the member <NUM> enables achievement of the targeted accuracy of measurement, regardless of the angle of measurement.

In the present embodiment, with the member <NUM>, alignment is performed between the criterial three-dimensional data and the measurement three-dimensional data. Thus, highly accurate acquisition of the coordinates and posture of the scanner <NUM> in the measurement device <NUM> need not be obtained. According to the present embodiment, the wear amount of the cutter ring <NUM> can be easily measured.

In the present embodiment, the member <NUM> has a plurality of faces facing in different directions. According to the present embodiment, regardless of the relative position between the measurement device <NUM> and the member <NUM> with the cutter ring <NUM> of the disc cutter <NUM>, geometric features of the member <NUM> can be detected, resulting in achievement of more accurate detection. According to the present embodiment, regardless of the relative position between the measurement device <NUM> and the member <NUM> with the cutter ring <NUM> of the disc cutter <NUM>, the wear amount of the cutter ring <NUM> can be measured highly accurately.

In the present embodiment, the member <NUM> is provided closer to the cutter chamber 30C in the tunnel boring machine <NUM>. According to the present embodiment, in excavation of the tunnel boring machine <NUM>, the excavation can be inhibited from being interfered with the member <NUM>, and the member <NUM> can be inhibited from wearing.

In the present embodiment, the member <NUM> together with the cutter ring <NUM> is located detectably in the detection area of the measurement device <NUM>. According to the present embodiment, the criterial three-dimensional data and the measurement three-dimensional data that indicate the three-dimensional shape of the cutter ring <NUM> and the member <NUM> can be easily acquired.

In the present embodiment, the member <NUM> is provided at a key block <NUM>. According to the present embodiment, the member <NUM> can be located so as not to interfere with replacement of the disc cutter <NUM>.

In the present embodiment, the member <NUM> is attached to the key block <NUM> by welding. If the member <NUM> is damaged or deformed, the member <NUM> can be easily replaced together with the key block <NUM>.

In the present embodiment, such a plurality of members <NUM> is provided around the disc cutter <NUM>. According to the present embodiment, in measurement of the measurement device <NUM>, an improvement can be made in the accuracy of alignment.

In the present embodiment, one member <NUM> is provided on one side in the axial direction of the cutter ring <NUM> and another member <NUM> is provided on the other side. According to the present embodiment, regardless of the relative position between the measurement device <NUM> and the members <NUM> with the cutter ring <NUM> of the disc cutter <NUM>, the members <NUM> can be detected. Thus, the present embodiment enables highly accurate alignment between the criterial three-dimensional data and the measurement three-dimensional data. According to the present embodiment, regardless of the relative position between the measurement device <NUM> and the members <NUM> with the cutter ring <NUM> of the disc cutter <NUM>, more accurate detection can be achieved.

In the present embodiment, each member <NUM> provided includes a humped shape protruding toward the cutter chamber 30C. According to the present embodiment, the accuracy of detection of the members <NUM> is inhibited from deteriorating due to the influence of clogging, for example, due to excavated muck in excavation.

In the present embodiment, the members <NUM> are each provided replaceably at a key block <NUM>. According to the present embodiment, for example, in a case where any member <NUM> is damaged, only the member <NUM> can be easily replaced. According to the present embodiment, the members <NUM> can be easily mounted on the conventional cutterhead <NUM>.

Such a member <NUM> as above may be fixed to a case <NUM>, a retainer <NUM> (retaining member), or a hub <NUM> by welding, instead of to a key block <NUM>. In this case, at the time of replacement, the member <NUM> needs to be detached by cutting.

An exemplary shape of a member 50A will be described with <FIG>. <FIG> is a front view of an exemplary member 50A. <FIG> is a side view of the member 50A illustrated in <FIG>. <FIG> is a plan view of the member 50A illustrated in <FIG>. The member 50A has a wall 51A different in shape from the wall <NUM> of the member <NUM>, and is smaller than the member <NUM>. The wall 51A has a length d21 shorter than the length d11 of the wall <NUM> of the member <NUM>. The wall 51A has a length d22 the same as the length d12 of the wall <NUM> of the member <NUM>. The distance d23 from the wall 51A to the joint between a wall 52A and a wall 53A is the same as the distance d13 of the member <NUM>. A circumferential edge 52a of the wall <NUM> and a circumferential edge 53a of the wall <NUM> are each joined to an end portion of the wall 51A. The wall 51A does not protrude outward from the wall <NUM> and the wall <NUM>. Such a shape of the member 50A can be made smaller than the member <NUM>.

An exemplary shape of a member 50B will be described with <FIG>. <FIG> is a front view of an exemplary member 50B. <FIG> is a side view of the member 50B illustrated in <FIG>. <FIG> is a plan view of the member 50B illustrated in <FIG>. The member 50B is smaller than the member 50A. A wall 51B has a length d31 the same as the length d21 of the wall 51A of the member 50A. The wall 51B has a length d32 shorter than the length d22 of the wall 51A of the member 50A. The distance d33 from the wall 51B to the joint between a wall 52B and a wall 53B is the same as the distance d23 of the member 50A. Such a shape of member 50B can be made smaller than the member <NUM> and the member 50A.

Here, measurement with the measurement device <NUM> and measurement with a conventional technique are evaluated in the accuracy of measurement. <FIG> is an explanatory graph of differences in the accuracy of measurement from the conventional technique. <FIG> is an explanatory graph of influence on the accuracy of measurement due to the angle of measurement. <FIG> is an explanatory graph of influence on the accuracy of measurement due to the angle of measurement. With a combination of the following three conditions, measurement was performed ten times in each condition.

(Condition <NUM>) Measurement is performed with a variation in the shape of a member <NUM> for use in alignment. More particularly, measurement with the measurement device <NUM> with the member <NUM>, the member 50A, and the member 50B described above for alignment and measurement with the conventional technique are performed. "Shape <NUM>" indicates measurement with the member <NUM>, "Shape <NUM>" indicates measurement with the member 50A, "Shape <NUM>" indicates measurement with the member 50B, and "Conventional Technique" indicates measurement with the conventional technique.

Here, measurement with the conventional technique will be described with <FIG> is a schematic explanatory view of alignment with the conventional technique. The conventional technique is a technique in which, without any member for alignment, the wear amount is measured with alignment, for example, based on the shape of a shoulder 41a that the cutter ring <NUM> of a disc cutter <NUM> has. A broken line indicates three-dimensional data acquired in the criterial state, a solid line indicates three-dimensional data acquired in an operation state, and a dot-and-dash line indicates three-dimensional data acquired in an operation state with further wear. From <FIG>, because of alignment based on the shape of the shoulder 41a of the cutter ring <NUM>, in a case where the shoulder 41a wears due to further wearing, obviously, it is difficult to perform alignment properly.

(Condition <NUM>) Measured is the wear amount of the cutter ring <NUM> of the disc cutter <NUM> that varies from <NUM> to <NUM> and then to <NUM>.

(Condition <NUM>) Measurement is performed at two angles of <NUM>° and <NUM>° as the angle of measurement.

Evaluation is performed on the basis of comparison in the root mean square error (RMSE) between a measured value fk with the measurement device <NUM> and a gage measured value yk with a gauge at each of n number of measurement points, calculated with the following Mathematical Expression <NUM>. Herein, the measurement point in front of the scanner <NUM> on the circumference of the disc cutter <NUM> is defined as <NUM>°, and measurement is performed in the range from -<NUM>° to <NUM>°. In the range, the wear amount is measured every <NUM>° for approximately <NUM> points in total. Note that the targeted RMSE is <NUM>.

From <FIG>, obviously, Shape <NUM>, Shape <NUM>, and Shape <NUM> are smaller in RMSE than the conventional technique. Obviously, in each of Shape <NUM>, Shape <NUM>, and Shape <NUM>, the difference in RMSE due to the differences in the wear amount is small. Regardless of the wear amount of the cutter ring <NUM> of the disc cutter <NUM>, Shape <NUM>, Shape <NUM>, and Shape <NUM> each fall below the targeted RMSE, resulting in achievement of the targeted accuracy of measurement.

From <FIG> and <FIG>, regardless of the angle of measurement, Shape <NUM>, Shape <NUM>, and Shape <NUM> are smaller in RMSE than the conventional technique. The conventional technique is larger in RMSE at an angle of measurement of <NUM>° than at an angle of measurement of <NUM>°. Shape <NUM>, Shape <NUM>, and Shape <NUM> are slightly larger in RMSE at an angle of measurement of <NUM>° than at an angle of measurement of <NUM>°, but fall below the targeted RMSE. Regardless of the angle of measurement, Shape <NUM>, Shape <NUM>, and Shape <NUM> fall below the targeted RMSE, resulting in achievement of the targeted accuracy of measurement.

In the above, the member <NUM>, the member 50A, and the member 50B are each formed of a combination of the wall <NUM>, the wall <NUM>, the wall <NUM>, the wall <NUM>, and the wall <NUM> planar in shape, but this is not the only configuration. The member <NUM>, the member 50A, and the member 50B may each be formed of a combination of a plurality of curved faces or may each be formed of a combination of a planar face and a curved face.

In the above, the controller <NUM> and the measurement controller <NUM> are separately provided, but the present invention is not limited to this. The controller <NUM> and the measurement controller <NUM> may be integrally provided.

Claim 1:
A tunnel boring machine (<NUM>) comprising:
a disc cutter (<NUM>) including a cutter ring (<NUM>); and
a member (<NUM>) for use in measurement of a wear amount of the cutter ring (<NUM>), wherein
the wear amount of the cutter ring (<NUM>) is measured with a three-dimensional shape measurement device (<NUM>), wherein
the member (<NUM>) is provided at a part constant in relative position to the cutter ring (<NUM>), and wherein
the member (<NUM>) is provided on each of one side and another side in an axial direction of the cutter ring (<NUM>) .