Leak location estimation device and leak location estimation method

Abstract

To provide a device and a method for estimating a leakage position that can easily specify the position of a leakage in a pipe arranged on one side of a shielding object, from another side of the shielding object.SOLUTION: A leakage position estimation device 30 includes: a reception unit 14 for receiving an electromagnetic wave signal from a signal output unit 26 at the top end of a wire arranged in a leakage position L1 in a pipe 10 on one side of a floor 14, in a work space R on another side of the floor 14; a storage unit 45 for storing the intensity of the electromagnetic wave signal at each point received at different points by the reception unit 14, as positional signal intensity information, with the reception positions; and an estimation unit for estimating the position of a transmission coil antenna as a leakage position L1 on the basis of plural pieces of positional signal intensity information D1.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a leakage location estimation device and a leakage location estimation method. [Background technology]

[0002] Conventionally, when a leak is detected in a gas supply pipe, it is necessary to identify the location of the leak. The following Patent Document 1 discloses a technology for detecting the flow velocity of a fluid in a pipe and identifying the location of the fluid leak based on the change in the flow velocity. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-101231 Summary of the Invention [Problem to be solved by the invention]

[0004] Although various techniques have been proposed for identifying the location of a leak in a pipe, when the pipe itself is covered by an obstruction, for example, when the pipe is covered by a floor or wall inside a building, the leak location cannot be seen directly. Therefore, it is necessary to identify the leak location through the obstruction, which makes it difficult to identify the exact location.

[0005] In consideration of the above-mentioned facts, the present invention aims to provide a leak position estimation device and a leak position estimation method that can easily identify the leak position of a pipe arranged on one side of a shield from the other side of the shield. [Means for solving the problem]

[0006] The leakage position estimation device of claim 1 comprises a receiver having a receiving coil antenna that receives an electromagnetic wave signal output from a transmitting coil antenna at the tip of a wire that is positioned at a position where a leakage has been confirmed in a pipe on one side of a shielding object, and receives the electromagnetic wave signal on the other side of the shielding object with the coil axis of the receiving coil antenna aligned along the shielding surface of the shielding object, a memory unit that stores the strength of each of the electromagnetic wave signals received at multiple different points by the receiver as position signal strength information together with the receiving position, and an estimation unit that estimates the position of the transmitting coil antenna as the leakage position based on the multiple position signal strength information.

[0007] In the leakage position estimation device according to claim 1, an electromagnetic wave signal output from a transmitting coil antenna arranged in a pipe on one side of a shielding object is received by a receiver on the other side of the shielding object. The receiver has a receiving coil antenna for receiving the electromagnetic wave signal, and receives the electromagnetic wave signal on the other side of the shielding object with the coil axis of the receiving coil antenna aligned along the shielding surface of the shielding object. The strength of each point of the electromagnetic wave signal received by the receiver at a plurality of different points is stored in a storage unit together with the reception position as position signal strength information, and the position of the transmitting coil antenna is estimated as the leakage position by an estimation unit based on the plurality of position signal strength information.

[0008] When a coil antenna is used for transmission and reception, there is unevenness in the distribution of electromagnetic waves at positions close to the transmitting coil antenna. Therefore, when receiving electromagnetic wave signals with a receiving coil antenna, the coil axis is received with the receiving coil antenna aligned with the shielding surface of the shielding object. This increases the probability that the coil axis of the transmitting coil antenna arranged on one side of the shielding object and the coil axis of the receiving coil antenna will be parallel, making it easier to estimate the relationship between the position of the transmitting coil antenna and the strength of the electromagnetic wave signal. Then, the estimating unit can estimate the position of the transmitting coil antenna based on multiple pieces of position signal strength information.

[0009] Furthermore, the position of the transmitting coil antenna can be easily estimated using a relatively inexpensive coil antenna for transmission and reception.

[0010] Claim 1 In the leakage position estimation device according to the present invention, the estimation unit estimates, within a reception area including a plurality of points at which the electromagnetic wave signal is received by the receiver, the center of symmetry of the electromagnetic wave intensity at the plurality of points as the leakage position.

[0011] Claim 1 According to the leakage position estimation device in accordance with the above, the leakage position can be estimated based on the fact that the intensity of the electromagnetic wave signal is distributed symmetrically with the transmitting coil antenna as the center.

[0012] Leakage In the leak position estimation device, the estimation unit estimates, as the leak position, peak parts of the electromagnetic wave intensity at a plurality of points within a reception area including a plurality of points where the electromagnetic wave signal is received by the receiver.

[0013] Leakage According to the leak position estimation device, the leak position can be estimated based on the presence of a peak portion of the electromagnetic wave intensity in the vicinity of the transmitting coil antenna.

[0014] Claim 2 In the leakage position estimation device according to the present invention, the estimation unit issues an error alert when peak portions of electromagnetic wave intensity at a plurality of points appear in a reception area including the plurality of points where the electromagnetic wave signal is received by the receiver.

[0015] When the angle between the coil axis of the transmitting coil antenna and the coil axis of the receiving coil antenna becomes large, the intensity distribution of the electromagnetic wave signal becomes biased, and the peak parts of the electromagnetic wave intensity may appear at multiple points within the receiving area. Therefore, in the leakage position estimation device according to claim 4, when the peak parts of the electromagnetic wave intensity at multiple points appear at multiple points within the receiving area, an error is notified. This allows the operator to rotate the coil axis of the receiving coil antenna and receive the electromagnetic wave signal again.

[0016] The leak location estimation method of claim 5 receives electromagnetic wave signals output from a transmitting coil antenna at the tip of a wire placed at a leak location where a leak has been confirmed in a pipe on one side of a shielding, at a plurality of different points with the coil axis of a receiving coil antenna aligned along the shielding surface on the other side of the shielding, obtains the intensities of the plurality of received electromagnetic wave signals together with the reception positions as position signal strength information, and estimates the position of the transmitting coil antenna based on the plurality of position signal strength information.

[0017] In the leakage position estimation method according to claim 5, an electromagnetic wave signal output from a transmitting coil antenna arranged in a pipe on one side of a shielding object is received at a plurality of different points on the other side of the shielding object. At this time, the receiving coil antenna receives the electromagnetic wave signal with its coil axis aligned along the shielding surface of the shielding object on the other side of the shielding object. Then, the strengths of the plurality of received electromagnetic wave signals are acquired together with the reception positions as position signal strength information, and the position of the transmitting coil antenna is estimated based on the plurality of position signal strength information.

[0018] When a coil antenna is used for transmission and reception, there is unevenness in the distribution of electromagnetic waves at positions close to the transmitting coil antenna. Therefore, when receiving electromagnetic signals with a receiving coil antenna, the coil axis is received with the receiving coil antenna aligned along the shielding surface of the shielding object. This increases the probability that the coil axis of the transmitting coil antenna arranged on one side of the shielding object and the coil axis of the receiving coil antenna will be parallel, making it easier to estimate the relationship between the position of the transmitting coil antenna and the strength of the electromagnetic signal. Then, the position of the transmitting coil antenna can be estimated based on multiple pieces of position signal strength information.

[0019] Furthermore, the position of the transmitting coil antenna can be easily estimated using a relatively inexpensive coil antenna for transmission and reception.

[0020] Claim 5 In the leakage position estimation method according to the present invention, the estimation estimates the leakage position as a center of symmetry of electromagnetic wave intensity at a plurality of points within a reception area including the plurality of points at which the electromagnetic wave signal is received.

[0021] Claim 5 According to the leakage position estimating method in accordance with the above, the leakage position can be estimated based on the fact that the intensity of the electromagnetic wave signal is distributed symmetrically with the transmitting coil antenna as the center.

[0022] Leakage The leak position estimating method estimates, within a reception area including a plurality of points from which the electromagnetic wave signal is received, peak portions of electromagnetic wave intensity at the plurality of points as the leak position.

[0023] Leakage According to the leak position estimation method, the leak position can be estimated based on the presence of a peak portion of the electromagnetic wave intensity in the vicinity of the transmitting coil antenna.

[0024] Claim 4 In the leakage position estimation method according to the present invention, when peak portions of the electromagnetic wave intensity at the multiple points appear in multiple locations within a reception area including the multiple points at which the electromagnetic wave signal is received, the direction of the coil axis of the receiving coil antenna is rotated by 20° or more and 90° or less along the shielding surface, and the electromagnetic wave signal is received again.

[0025] When the angle between the coil axis of the transmitting coil antenna and the coil axis of the receiving coil antenna becomes large, the intensity distribution of the electromagnetic wave signal becomes biased, and the electromagnetic wave intensity peaks may appear at multiple points within the receiving area. Therefore, in the leakage position estimation method according to claim 8, when the electromagnetic wave intensity peaks appear at multiple points, the direction of the coil axis of the receiving coil antenna is rotated by 20° to 90° along the shielding surface, and the electromagnetic wave signal is received again. This makes it possible to reduce the angle between the coil axis of the transmitting coil antenna and the coil axis of the receiving coil antenna. Effect of the Invention

[0026] According to the leak position estimation device and the leak position estimation method of the present invention, the leak position in a pipe arranged on one side of a shield can be easily estimated from the other side of the shield. [Brief description of the drawings]

[0027] [Figure 1] 1 is a diagram showing a partial configuration of a building in which a leakage position estimation device according to an embodiment of the present invention is used; [Figure 2A] FIG. 2 is a schematic diagram of a searching tool used in the present embodiment. [Figure 2B] FIG. 13 is a diagram showing a state in which a leak location in a pipe is being detected using a detection tool. [Figure 3A] FIG. 2 is a schematic diagram of a transmitter used in the present embodiment. [Figure 3B] 13 is a diagram showing a state in which a signal transmitting portion of the transmitting device is disposed at a leakage position. FIG. [Figure 4A] 1 is a perspective view of a leakage position estimation device according to an embodiment of the present invention as viewed from a camera side. [Figure 4B] 1 is a perspective view of a leakage location estimating device according to an embodiment of the present invention, as viewed from a display unit side. [Diagram 5] FIG. 2 is a block diagram showing a control system of the leakage location estimation device according to the present embodiment. [Figure 6] 1 is a diagram showing a state in which the leakage position estimation device of the present embodiment receives a signal near the leakage position. FIG. [Figure 7] 4 is a flowchart of a leakage position estimation processing program executed by the controller. [Figure 8] 11 is a diagram showing a state in which half of a target image has been scanned and is displayed on the display unit of the leak position estimating device of the present embodiment. FIG. [Figure 9] 11 is a diagram showing a state in which scanning of the entire surface of a target image is completed on the display unit of the leak position estimating device of the present embodiment. FIG. [Figure 10] 11 is a flowchart of a symmetry center estimation process according to the present embodiment. [Figure 11] FIG. 10A is a diagram showing a state in which intensity information is displayed in each square of a target image, and FIG. 10B is a diagram showing a state in which validity information is displayed. [Figure 12] FIG. 13A is a diagram for explaining a procedure for determining a symmetrical position in the X direction based on valid information, and FIG. 13B is a diagram showing a state in which the intersection of the symmetrical positions in the X direction and the Y direction is displayed. [Figure 13] 1 is an explanatory diagram showing the angle θ between the coil axis S of a transmitter and the coil axis of a receiver. [Figure 14] 13A is a diagram showing the distribution of intensity information K1 when the angle θ is 30°, and FIG. 13B is a diagram showing the distribution of intensity information K1 when the angle θ is 50°. [Figure 15] 13A is a diagram showing the distribution of intensity information K1 when the angle θ is 70°, and FIG. 13B is a diagram showing the distribution of intensity information K1 when the angle θ is 90°. [Figure 16] 4 is a flowchart of a peak position estimation processing program executed by the controller. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] An embodiment of a leakage location estimation device and method according to the present invention will be described below. In this embodiment, a case where a gas leakage is detected in a building will be described as an example.

[0029] As shown in FIG. 1, the subject piping 10 is arranged along the wall 12 and floor 14 of a building, and supplies gas to a gas consuming appliance (not shown). The wall 12 has an inner wall 12A and an outer wall 12B that are parallel to each other. The inner wall 12A is disposed on the indoor side and divides the indoor space, and the outer wall 12B divides the outside space from the inside of the wall 12D. The inner wall 12A and the floor 14 correspond to the shield of the present invention. In this embodiment, an inspection hatch 12C is provided in the outer wall 12B, and an opening 10A of the piping 10 is provided at a position corresponding to the inspection hatch 12C. The inside of the piping 10 can be accessed from the inspection hatch 12C and the opening 10A.

[0030] The piping 10 is disposed on one side of an inner wall 12A and a floor 14. The other side of the inner wall 12A and the floor 14 is the room interior, that is, a work space R.

[0031] The leak position L1 in the pipe 10 can be identified in advance using a search tool 16 in the following manner. As shown in Fig. 2A, the search tool 16 has an air tube 16A and a balloon 16B. The balloon 16B is attached to the tip of the air tube 16A. One end of the air tube 16A is connected to the inlet of the balloon 16B, and air can be sent into the balloon 16B from the other end using a blowing means such as a rubber bulb 16C.

[0032] As shown in FIG. 2B, the search for the leak position L1 with the search tool 16 is performed by inserting the air pipe 16A from the balloon 16B side into the piping 10 from the inspection hatch 12C from the balloon 16B side with the air deflated. Then, air is sent at an arbitrary position to block the piping 10 with the balloon 16B, and the airtight state downstream of the blocking position is confirmed to determine whether there is a leak downstream of the blocking position. By changing the position of the balloon 16B and repeating the above operation, the position of the balloon 16B where the airtight state is maintained and the position of the balloon 16B where the airtight state is not maintained are brought closer to each other, and the position of the balloon 16B closest to the consumer device where the airtight state is maintained can be determined as the leak position L1. The insertion length of the air pipe 16A of the search tool 16 allows the distance from the inspection hatch 12C to the leak position L1 to be confirmed.

[0033] Next, the transmitting device 20 will be described.

[0034] As shown in Fig. 3A, the transmitter 20 has a power supply unit 22, a wire 24, and a signal transmitter 26. The signal transmitter 26 is provided at the tip of the wire 24, and is configured as an antenna including a coil 26A (transmitter coil antenna). The axial direction S of the coil 26A is arranged along the extension direction of the wire 24 (extension direction of the pipe 10). The maximum diameter 26R of the coil 26A is set to be smaller than the inner diameter of the pipe 10. By passing a current from the power supply unit 22, an electromagnetic wave is generated from the signal transmitter 26, and the electromagnetic wave is transmitted as a signal.

[0035] 3B, the wire 24 of the transmitting device 20 is inserted into the piping 10 from the side of the signal transmitting unit 26 through the inspection hatch 12C and the opening 10A. By making the insertion length of the wire 24 the same as the insertion length when the leak position L1 is detected by the searching tool 16, the signal transmitting unit 26 can be positioned at the leak position L1.

[0036] Next, the leakage position estimation device 30 of this embodiment will be described. As shown in Figures 4A and 4B, the leakage position estimation device 30 of this embodiment has a main body unit 32, a receiver 34, a connection bar 36, a camera 38, a position measuring device 48, and a display unit 50.

[0037] The receiver 34 is configured with an antenna including a coil 34A (hereinafter referred to as the "receiving coil antenna 34A"), and receives an electromagnetic wave signal from the signal transmission unit 26. The coil axis S2 of the receiving coil antenna 34A is disposed at an angle with respect to the extending direction of the connecting bar 36. In the measurement work described below, the coil axis S2 of the receiving coil antenna 34A is disposed close to the floor 14 in a direction along the floor surface (parallel to the floor surface).

[0038] The connecting bar 36 is rod-shaped, and the receiver 34 is attached to the tip of the connecting bar 36. The main body 32 is attached to the base end of the connecting bar 36 via an attachment portion 37.

[0039] The main body 32 is substantially rectangular in front view and has a thin rectangular parallelepiped shape. The main body 32 includes a housing 39, a controller 40, a camera 38, a position measuring device 48, and a display unit 50. The controller 40, the position measuring device 48, and the display unit 50 are housed in the housing 39. The housing 39 is transparent in a portion corresponding to the display unit 50 so that the information displayed on the display unit 50 can be seen from the outside. The display unit 50 is disposed on one side 32A of the main body 32, and the camera 38 is disposed on the other side 32B of the main body 32 opposite to the display unit 50. An image captured by the camera 38 is displayed on the display unit 50 via the controller 40. The receiver 34 is included in the range of the image captured by the camera 38. In the image captured by the camera 38, the position of the receiver 34 is identified, and the strength K1 of the electromagnetic waves received at that position, together with the position information P1 measured by the position measuring device 48, is stored in the memory unit 45 described later as position signal strength information D1.

[0040] The housing 39 constitutes the outer shape of the main body 32, and the mounting part 37 is attached so as to sandwich the housing 39 in the thickness direction. The mounting part 37 has a pocket 37A for inserting the connecting bar 36 and a fixing part 37B that is fixed to the housing 39.

[0041] The position measuring device 48 measures the position of the receiver 34 and outputs position information P1 to the controller 40. The position measuring can be performed using a GPS, LiDAR, or the like. Also, a marker or a QR code (registered trademark) (not shown) may be attached to the receiver 34 for recognition by the camera 38 to measure the position.

[0042] As shown in Fig. 5, the controller 40 is electrically connected to the receiver 34, the camera 38, the position measuring device 48, and the display unit 50. Fig. 5 is a block diagram showing an example of the electrical configuration of the controller 40 according to the present embodiment.

[0043] As shown in FIG. 5, the controller 40 includes a central processing unit (CPU) 41, a read only memory (ROM) 42, a random access memory (RAM) 43, an input / output interface (I / F) 44, and a storage unit 45.

[0044] The CPU 41, the ROM 42, the RAM 43, and the I / F 44 are connected to each other via a bus 46. The I / F 44 is connected to each of the functional units including a storage unit 45. These functional units are capable of communicating with the CPU 41 mutually via the I / F 44.

[0045] For example, a hard disk drive (HDD), a solid state drive (SSD), a flash memory, etc. are used as the storage unit 45. The storage unit 45 stores a control program for controlling each part of the leakage position estimation device 30 and various data. The control program and various data may be stored in the ROM 42.

[0046] In this embodiment, a position estimation processing program and the like are stored as part of the control program. In addition, position signal strength information D1, strength information K1, position information P1, and the like are stored as data used in this processing.

[0047] Next, the operation of the leakage position estimating device 30 of this embodiment will be described.

[0048] The leakage position estimation device 30 is used in the working space R, as shown in Fig. 6. The signal transmission unit 26 of the transmitting device 20 is placed at the leakage position L1 in advance, and a current is applied from the power supply unit 22. This causes the signal transmission unit 26 to transmit an electromagnetic wave signal.

[0049] The operator places the receiver 34 of the leak position estimation device 30 in a low position near the floor 14 in the vicinity of the estimated leak position L1 so that the coil axis S2 of the receiving coil antenna 34A is along the floor surface, and turns on the power (not shown). When the power is turned on, the camera 38 starts capturing images, and the captured images (target images G) are displayed on the display unit 50 at a predetermined rate. The receiver 34 starts receiving electromagnetic signals, and the position locator 48 determines the position of the receiver 34. The camera 38, LiDAR, etc. start acquiring spatial shapes, a spatial map is created, and self-position estimation is performed. The controller 40 then executes a leakage position estimation processing program shown in FIG. 7.

[0050] In the leak position estimation processing program, the target image G is divided into a grid, and the intensity information K1 for the position corresponding to each grid is acquired sequentially. Therefore, the operator moves (scans) the receiver 34 along the grid of the target image G to acquire the intensity information K1. Note that the target image G is an image corresponding to a target area that is set in advance at a position estimated to include the leak position L1 based on the insertion length of the wire 24 of the transmitter 20, etc., and one grid corresponds to a pixel on the target image G.

[0051] In step S10, position information P1 of the receiver 34 measured by the position measuring device 48 is acquired, in step S12, intensity information K1 of the electromagnetic wave signal received by the receiver 34 is acquired, and in step S14, position signal intensity information D1 that corresponds to the acquired position information P1 and the intensity information K1 is created and stored in the memory unit 45.

[0052] Next, in step S16, the intensity information K1 is displayed on the display unit 50. The intensity information K1 is displayed based on the position information P1 by displaying the intensity information K1 at the corresponding position of each of the grid-like partitions of the target image G displayed on the display unit 50 (mapping display). In Fig. 8 and Fig. 9, the intensity information K1 is expressed by shading, with darker areas indicating lower intensity and lighter colors (white) indicating higher intensity.

[0053] The worker confirms that the intensity information K1 is displayed in the corresponding position, and then moves the receiver 34 to the next square.

[0054] Next, in step S18, it is determined whether scanning has been completed in the target area, that is, whether intensity information K1 has been acquired for all the squares. If the determination is negative, the process proceeds to step S20, where it is determined whether the positional movement of the receiver 34 (movement to the next position by the operator) has been completed. If the positional movement has not been completed, the process waits until the positional movement is completed. If the positional movement has been completed, the process returns to step S10, and the above process is repeated. In this way, it is possible to obtain intensity information K1 at each square position in the target image G. FIG. 8 shows that the intensity information K1 has been acquired for approximately half of the positions in the target image G, and FIG. 9 shows that the intensity information K1 has been acquired for all the squares in the target image G.

[0055] If the determination in step S18 is affirmative, the process proceeds to step S30, where the symmetry center estimation process shown in FIG. 10 is executed.

[0056] In the symmetry center estimation process, first in step S32, the average value of intensity information K1 of all squares in the target image G is calculated, and in step S34, only parts equal to or greater than the average value are left as valid areas. Fig. 11(A) is a diagram displaying intensity information K1 of all squares in the target image G, and Fig. 11(B) is a diagram displaying intensity information K1 only of the valid areas left in the process of step S34.

[0057] Next, in step S36, the symmetrical position of the intensity information K1 in the X direction in the target image is calculated. The symmetrical position is calculated by finding the "distance x intensity information K1" of each square (pixel) on both sides (left and right) of an arbitrary position in the X direction of the effective area (indicated by vertical lines and an x ​​in FIG. 12(A)), and comparing the sum of the found values ​​on one side (left side) with the sum of the found values ​​on the other side (right side). The position where the difference between the sum of one side and the sum of the other side is the smallest is determined to be the symmetrical position of the intensity information K1 in the X direction in the target image.

[0058] Next, in step S38, the symmetrical position of the intensity information K1 in the Y direction in the target image is calculated. To calculate the symmetrical position, similar to step S36, the "distance x intensity information K1" of each square (pixel) on both sides (top and bottom) of the effective area from an arbitrary position in the Y direction is calculated, and the sum of the calculated values ​​on one side (top) is compared with the sum of the calculated values ​​on the other side (bottom). The position where the difference between the sum of one side and the sum of the other side is the smallest is determined to be the symmetrical position of the intensity information K1 in the Y direction in the target image.

[0059] Next, in step S40, the intersection point of the calculated symmetrical position in the X direction and the symmetrical position in the Y direction is determined as the center of symmetry. In Fig. 12(B), this is the position of x. In the process of step S40, the symmetry center estimation process is terminated, and the process proceeds to step S22 shown in Fig. 7, where the symmetry center is displayed on the display unit 50 as the estimated leak position, and the leak position estimation process program is terminated.

[0060] According to the leakage position estimation processing program of this embodiment, the leakage position L1 can be easily estimated based on the position signal strength information D1.

[0061] Here, the angle between the coil axis S of the transmitter 20 and the coil axis S2 of the leakage position estimation device 30 will be described. Since the signal transmitting unit 26 of the transmitter 20 is inserted into the pipe 10 arranged under the floor 14, the coil axis S is parallel to the floor surface of the floor 14, but the direction is unknown. Therefore, the angle θ (see FIG. 13) between the coil axis S and the coil axis S2 of the receiver 34 of the leakage position estimation device 30 is also unknown.

[0062] It was confirmed by experiments that when the angle θ (see FIG. 13) between the coil axis S and the coil axis S2 becomes large, multiple peaks appear in the target image G. This is thought to be because, due to the relationship between the directions of the coil axis S and the coil axis S2 and the electromagnetic wave distribution, a phenomenon occurs in which the strength of the electromagnetic waves received by the receiver 34 becomes weak depending on the location even if the distance from the signal transmission unit 26 is close.

[0063] 14(A), 14(B), 15(A), and 15(B) show the distribution of intensity information K1 in the target image G when the angle θ is 30°, 50°, 70°, and 90°, respectively. Note that FIG. 11(A) shows the distribution of intensity information K1 in the target image G when the angle θ is 0°. In these figures, peaks are indicated by circles. When the angle θ is 0° and 30°, there is one intensity peak in the intensity information K1 in the target image G. On the other hand, when the angle θ is 50°, 70°, and 90°, there are multiple intensity peaks in the intensity information K1 in the target image G.

[0064] In this way, even if multiple peaks appear, the symmetry center estimation process can determine the parts marked with "X" in Figures 14(A), 14(B), 15(A), and 15(B) as the symmetry center, making it easy to estimate the leakage position L1.

[0065] In this embodiment, the intensity information K1 is obtained for each square, but it is not necessary to obtain the intensity information K1 according to the square, and the intensity information K1 may be obtained at any position. The symmetry center estimation process may be performed based on the intensity information K1 at the any position.

[0066] In this embodiment, the symmetry center is determined by the symmetry center estimation process to estimate the leak position L1, but the peak part PE of the intensity information K1 in the target image G may be estimated as the leak position L1. Here, the "peak part PE" refers to a part where the intensity information K1 of the corresponding square part is clearly higher than the surrounding square parts. When estimating the peak part PE as the leak position L1, a peak position estimation processing program shown in FIG. 16 is executed.

[0067] Steps S10 to S20 are executed as described above. If the determination in step S18 is positive, the process proceeds to step S50. In step S50, it is determined whether there is one peak part PE in the intensity information K1 in the target image G. If there is one peak part PE, the process proceeds to step S22, where the peak part PE is displayed on the display unit 50 as the estimated leak position, and the leak position estimation processing program is terminated. If there are multiple peak parts PE, the process proceeds to step S52, where an error is displayed on the display unit 50, and the peak position estimation processing program is terminated.

[0068] If an error display is confirmed, it is highly likely that the angle θ is greater than 30°. Therefore, the operator rotates the direction of the coil axis S2 of the receiver 34 along the floor surface of the floor 14. The rotation angle is preferably 20° or more and less than 90°. In this way, the angle θ is reduced by rotating the direction of the coil axis S2 along the floor surface of the floor 14. After reducing the angle θ, the position signal intensity information D1 (intensity information K1) of the target area is acquired again, so that one peak portion can be estimated as the leakage position L1. With the above-mentioned symmetry center estimation process, the leakage position L1 can be estimated based on the information from one scan, regardless of the angle θ.

[0069] By identifying the leakage position L1 in this way, the opening to be formed by breaking the floor 14 during repairs can be made smaller, and work costs can also be reduced.

[0070] In this embodiment, the electromagnetic wave signal intensity information K1 is displayed on the display unit 50 of the leakage position estimation device 30, but the target image G may be displayed on a display unit of another terminal. [Explanation of symbols]

[0071] 12A Inner wall (shielding object) 14 Floor (shield) 26 Signal transmitter (transmitting coil antenna) 30 Leak location estimation device 34 Receiver 34A Receiving coil antenna 40 Controller (Estimation section) 45 Storage section θ angle D1 Location signal strength information K1 Strength Information L1 Leak location PE peak

Claims

1. a receiver having a receiving coil antenna for receiving an electromagnetic wave signal output from a transmitting coil antenna at a tip of a wire disposed at a position where a leak has been confirmed in a pipe on one side of a shield, and receiving the electromagnetic wave signal on the other side of the shield with the coil axis of the receiving coil antenna aligned along the shielding surface of the shield; a storage unit that stores the strength of each of the electromagnetic signals received at a plurality of different points by the receiver as position signal strength information together with the reception position; an estimation unit that estimates a position of the transmitting coil antenna as a leakage position based on a plurality of pieces of position signal strength information; Equipped with the estimation unit estimates, within a reception area including a plurality of points at which the electromagnetic wave signal is received by the receiver, a symmetric center of electromagnetic wave intensity at the plurality of points as the leakage position; Leak location estimation device.

2. a receiver having a receiving coil antenna for receiving an electromagnetic wave signal output from a transmitting coil antenna at a tip of a wire disposed at a position where a leak has been confirmed in a pipe on one side of a shield, and receiving the electromagnetic wave signal on the other side of the shield with the coil axis of the receiving coil antenna aligned along the shielding surface of the shield; a storage unit that stores the strength of each of the electromagnetic signals received at a plurality of different points by the receiver as position signal strength information together with the reception position; an estimation unit that estimates a position of the transmitting coil antenna as a leakage position based on a plurality of pieces of position signal strength information; Equipped with the estimation unit issues an error notification when peak portions of electromagnetic wave intensity at a plurality of points appear in a reception area including the plurality of points where the electromagnetic wave signal is received by the receiver. Leak location estimation device.

3. Electromagnetic wave signals output from a transmitting coil antenna at the tip of a wire that is placed at a leak location in the piping on one side of the shielding, the transmitting coil antenna receiving the electromagnetic wave signals being received at a plurality of different points on the other side of the shielding with the coil axis of the receiving coil antenna aligned along the shielding surface; acquiring the intensities of the received electromagnetic signals together with the reception positions as position signal intensity information; estimating a location of the transmitting coil antenna based on a plurality of the location signal strength information; The estimation estimates the leakage position as a symmetric center of electromagnetic wave intensity at a plurality of points within a receiving area including the plurality of points at which the electromagnetic wave signal is received. Leak location estimation method.

4. Electromagnetic wave signals output from a transmitting coil antenna at the tip of a wire that is placed at a leak location in the piping on one side of the shielding, the transmitting coil antenna receiving the electromagnetic wave signals being received at a plurality of different points on the other side of the shielding with the coil axis of the receiving coil antenna aligned along the shielding surface; When peak portions of the electromagnetic wave intensity at the plurality of points appear in a plurality of locations within a receiving area including the plurality of points at which the electromagnetic wave signal is received, the direction of the coil axis of the receiving coil antenna is rotated by 20° or more and 90° or less along the shielding surface, and the electromagnetic wave signal is received again; acquiring the intensities of the received electromagnetic signals together with the reception positions as position signal intensity information; estimating a location of the transmit coil antenna based on a plurality of the location signal strength information. Leak location estimation method.

Images