Conveyor belt wear sensing system and method

Abstract

To provide a wear detection system and method capable of grasping the wear state of the surface of a conveyor belt in more detail with high accuracy at a low cost.SOLUTION: The passive type IC tags 3 are embedded at a plurality of width-direction positions spaced apart from each other in a width direction of the conveyor belt 17 and at a plurality of thickness-direction positions spaced apart from each other in a thickness direction of the conveyor belt 17, and while the conveyor belt 17 is traveling, a transmission radio wave R1 is transmitted from a detector 10 disposed at a predetermined detection position near the conveyor belt 17 toward each IC tag 3. The abrasion state of the upper cover rubber 20 of the conveyor belt 17 is grasped by an arithmetic device 13 based on the magnitude of the received signal strength RSSI of the return radio wave R2 returned according to the transmission radio wave R1 every time each IC tag 3 passes the detection position by a detector 10.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a system and method for detecting wear on a conveyor belt, and more particularly to a system and method for detecting wear on a conveyor belt that is low cost and capable of determining the state of wear on the surface of the conveyor belt in more detail and with higher accuracy. [Background technology]

[0002] Conveyor belts running around conveyor devices transport a variety of objects to their destinations. Because a variety of objects are fed onto the conveyor belt, the surface of the conveyor belt wears over time due to these objects. Excessive surface wear increases the risk of damage to the traction layer, so it is important to understand the wear state.

[0003] Various methods using RFID tags have been proposed to determine the wear state of the surface of a conveyor belt (see, for example, Patent Document 1). In the method proposed in Patent Document 1, RFID tags are embedded in the conveyor belt, and a reader begins to detect these RFID tags. When the surface cover rubber is only slightly worn, communication between the reader and RFID tag is not possible, but as the cover rubber wears further, communication between the two becomes possible. When communication between the two becomes possible, it is determined that the cover rubber has reached its wear limit, and an alarm is activated.

[0004] Using an RFID tag and a reader as in this method, it is possible to detect the wear on the surface of a conveyor belt at low cost. However, this method only determines whether the cover rubber has reached its wear limit, and does not provide detailed information such as the presence or absence of uneven wear or the progress of wear. Therefore, there is room for improvement in order to accurately and in detail determine the wear state of the surface of a conveyor belt at low cost. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-16227 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a wear detection system and method that is low cost and can accurately and in detail grasp the wear state of the surface of a conveyor belt. [Means for solving the problem]

[0007] In order to achieve the above object, the conveyor belt wear detection system of the present invention comprises a plurality of passive IC tags embedded in the conveyor belt, a detector arranged at predetermined detection positions near the conveyor belt and configured to wirelessly communicate with each of the IC tags without contacting the conveyor belt, and a computing device connected to the detector so as to be able to communicate with the detector, wherein the IC tags are embedded at a plurality of widthwise positions spaced apart in the width direction of the conveyor belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the conveyor belt, and the detector emits radio waves toward each of the IC tags while the conveyor belt is running, and the computing device determines the wear state of the surface of the conveyor belt based on the strength of the signal received by the detector of the reply radio waves returned from each of the IC tags in response to the emitted radio waves each time the IC tag passes the detection position.

[0008] The conveyor belt wear detection method of the present invention uses a plurality of passive IC tags embedded in the conveyor belt, a detector arranged at predetermined detection positions near the conveyor belt and configured to wirelessly communicate with each of the IC tags without contacting the conveyor belt, and a computing device communicatively connected to the detector, wherein the IC tags are embedded at a plurality of widthwise positions spaced apart in the width direction of the conveyor belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the conveyor belt, the detector emits radio waves toward each of the IC tags while the conveyor belt is running, the detector receives signal strengths of reply radio waves from each of the IC tags in response to the emitted radio waves each time the IC tag passes the detection position, and the computing device determines the state of wear on the surface of the conveyor belt based on the magnitude of each received signal strength. [Effects of the Invention]

[0009] According to the present invention, a low-cost configuration can be achieved by using a simple configuration including multiple passive IC tags embedded in a conveyor belt, a detector that wirelessly communicates with each of the IC tags, and a computing device communicatively connected to the detector. The IC tags are embedded at each of the widthwise and thicknesswise positions, and the computing device determines the state of wear on the surface of the conveyor belt based on the strength of the signal received by the detector of the return radio waves returned from each of the IC tags. The magnitude of the received signal strength varies depending on the depth to which each IC tag is embedded from the surface of the conveyor belt, so using the strength of the received signal strength as an indicator is advantageous for accurately determining details such as the presence or absence of uneven wear on the surface of the conveyor belt and the progress of wear. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is an explanatory diagram illustrating a side view of a conveyor belt to which an embodiment of a conveyor belt wear detection system is applied; [Figure 2] 2 is a cross-sectional view taken along the line AA in FIG. 1. [Figure 3] FIG. 3 is a view taken along the arrow BB in FIG. 2. [Figure 4] 4 is an explanatory diagram illustrating the embedded position of the IC tag in FIG. 3 in a vertical cross section of the conveyor belt. FIG. [Figure 5] FIG. 2 is an explanatory diagram illustrating an IC tag in plan view. [Figure 6] 6 is an explanatory diagram illustrating the IC tag of FIG. 5 in cross section. [Figure 7] 10 is a graph diagram illustrating a schematic example of the relationship between the buried depth of an IC tag from the surface of a conveyor belt and the received signal strength of a return radio wave. [Figure 8] FIG. 2 is a graph illustrating a cross-sectional view of the wear state of the surface of the conveyor belt. [Figure 9] 1 is an explanatory diagram illustrating, in plan view, an example of a buried object having a linear detection element and an IC tag that form a loop circuit. [Figure 10] 10 is an explanatory diagram illustrating the buried body of FIG. 9 as seen from the front. FIG. [Figure 11] 10 is an explanatory diagram illustrating a conveyor belt in which the embedding members of FIG. 9 are embedded, as viewed from above. FIG. [Figure 12] 12 is an explanatory diagram illustrating the embedding positions of the IC tag and the embedded object in FIG. 11 as viewed in cross section of the conveyor belt. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A system and method for detecting wear in a conveyor belt according to the present invention will be described below based on the embodiments shown in the drawings.

[0012] The embodiment of a conveyor belt wear detection system 1 (hereinafter referred to as detection system 1) illustrated in Figures 1 to 4 detects the degree of wear on the surface of a conveyor belt 17. A conveyor device 14 includes a pair of pulleys 15a and 15b and a conveyor belt 17 stretched between the pulleys 15a and 15b. The conveyor belt 17 is supported between the pulleys 15a and 15b by a number of support rollers 16. Arrows L, W, and D in the figures indicate the longitudinal direction (belt longitudinal direction), width direction (belt width direction), and thickness direction (belt thickness direction) of the conveyor belt 17, respectively. Also, a dashed line CL in the figures indicates the center of the belt in the width direction.

[0013] The conveyor belt 17 is configured by integrating an upper cover rubber 20, a lower cover rubber 21, and a traction layer 18 disposed therebetween. The traction layer 18 is formed by arranging a large number of steel cords 19 extending in the longitudinal direction L in parallel in the width direction and joining these steel cords 19 via a coating rubber (adhesive rubber). The traction layer 18 is not limited to steel cords 19, and may also be a fiber layer made of canvas or the like. The conveyor belt 17 may be equipped with other components as necessary.

[0014] On the carrier side of the conveyor device 14 (the upper side in Figs. 1 and 2), the lower cover rubber 21 of the conveyor belt 17 is supported by the support rollers 16, so that the conveyor belt 17 has a trough shape with the central part in the width direction protruding downward. The conveyed object C is placed on the upper surface of the upper cover rubber 20 and conveyed. On the return side of the conveyor device 14 (the lower side in Figs. 1 and 2), the upper cover rubber 20 of the conveyor belt 17 is supported in a flat state by the support rollers 16.

[0015] This detection system 1 includes a plurality of passive IC tags 3 embedded in a conveyor belt 17, a detector 10 that wirelessly communicates with each of the IC tags 3, and a computing device 13 that is communicatively connected to the detector 10. In this embodiment, each of the IC tags 3 is embedded in the upper cover rubber 20 in order to determine the degree of wear on the surface of the upper cover rubber 20.

[0016] The IC tags 3 are embedded at a plurality of widthwise positions spaced apart in the width direction of the belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the belt. In this embodiment, the IC tags 3 embedded at a plurality of widthwise positions and a plurality of thicknesswise positions are further embedded at a plurality of longitudinal positions spaced apart in the longitudinal direction of the belt. That is, the respective widthwise positions and respective thicknesswise positions at which the IC tags 3 are embedded are set at a plurality of longitudinal positions spaced apart in the longitudinal direction of the belt.

[0017] In this embodiment, IC tags 3 are embedded in three locations in the belt width direction: the center and both end portions. The number of widthwise positions at which IC tags 3 are embedded and spaced apart in the belt width direction is not limited to three, but may be, for example, 2 to 10, and more preferably 3 to 6. The intervals Wa between adjacent IC tags 3 in the belt width direction are preferably equal. To grasp the wear state of the upper cover rubber 20 in more detail, however, it is preferable that IC tags 3 are embedded in as many widthwise positions as possible. However, if the number of widthwise positions is too large, costs may increase and it may become difficult to maintain good durability of the upper cover rubber 20.

[0018] In this embodiment, the IC tags 3 are embedded at three spaced locations in the belt thickness direction. The number of widthwise positions at which the IC tags 3 are embedded at intervals in the belt thickness direction is not limited to three, and may be, for example, about 2 to 6. The interval Ha between adjacent IC tags 3 in the belt thickness direction is preferably equal. To grasp the wear state of the cover rubber 20 in more detail, however, it is preferable that the IC tags 3 are embedded at more thicknesswise positions, but if the number of thicknesswise positions is too large, costs may increase and it may become difficult to maintain good durability of the upper cover rubber 20.

[0019] In this embodiment, the IC tags 3 are embedded at intervals La in the belt longitudinal direction. This interval La is, for example, 10 m to 50 m, more preferably 10 m to 20 mm. The IC tags 3 embedded at intervals along the belt longitudinal direction can be set at equal intervals along the entire length of the conveyor belt 17, or can be concentrated (distributed unevenly) in a specific longitudinal range. To grasp the wear state of the upper cover rubber 20 in more detail, it is preferable to embed the IC tags 3 at as many longitudinal positions as possible. However, an excessive number of longitudinal positions may increase costs and make it difficult to maintain the durability of the upper cover rubber 20. To grasp the wear state of the lower cover rubber 21, each IC tag 3 may be embedded in the lower cover rubber 21 in the same manner as described above.

[0020] 5 and 6, the IC tag 3 has an IC chip 4 and an antenna unit 5 connected to the IC chip 4. The IC chip 4 and the antenna unit 5 are disposed on a substrate 6. The IC chip 4 and the antenna unit 5 are covered with an insulating layer 6a, and the entire IC tag 3 is electrically insulated from the outside.

[0021] The IC tag 3 may be of a generally available specification, for example, an RFID tag (general-purpose product). The size of the IC tag 3 is, for example, an area of ​​200 mm 2 More than 6000mm 2 Less than 300mm, preferably 2 More than 2700mm 2 The thickness is, for example, 0.01 mm or more and 0.4 mm or less, more preferably 0.03 mm or more and 0.15 mm or less. The heat resistance temperature of the IC tag 3 is, for example, about 250°C.

[0022] The IC chip 4 stores in advance unique information that distinguishes the IC tag 3 from other IC tags 3. Although it is possible to store other information in the IC chip 4, in this detection system 1, it is sufficient that only the unique information of the IC tag 3 is stored in the IC chip 4. Therefore, no special information is stored in the IC chip 4.

[0023] The detector 10 is disposed at a predetermined detection position near the conveyor belt 17, and communicates wirelessly with each IC tag 3 without contacting the conveyor belt 17. More specifically, the detector 10 is disposed opposite a position where the IC tags 3 pass as the conveyor belt 17 travels. In this embodiment, the detector 10 is disposed on the return side of the conveyor belt 17, close to the surface of the upper cover rubber 20. The IC tags 3 are disposed at three positions on the conveyor belt 17 at intervals in the belt width direction, and correspondingly, the detectors 10 are disposed at three positions at intervals in the belt width direction.

[0024] The detector 10 has a transmitter 11 and a receiver 12. The transmitter 11 transmits an outgoing radio wave R1 toward the IC tag 3. The receiver 12 receives a reply radio wave R2 returned from the IC tag 3 (antenna unit 5) in response to the outgoing radio wave R1, and acquires the received signal strength RSSI of the reply radio wave R2 and the unique information of the IC tag 3 stored in the IC chip 4 that is transmitted together with the reply radio wave R2.

[0025] Here, the received signal strength RSSI of the reply radio wave R2 will be described in detail. As the conveyor belt 17 travels, each IC tag 3 repeatedly passes the detection position where the detector 10 is located. When an IC tag 3 approaches the detection position where the detector 10 is located, the detector 10 receives the reply radio wave R2 from each IC tag 3. As shown by the data S illustrated in FIG. 7 , as each IC tag 3 passes the detection position, the smaller the buried depth of the IC tag 3 from the surface of the upper cover rubber 20, the higher the received signal strength RSSI of the reply radio wave R2 from the IC tag 3 received by the detector 10. In other words, the magnitude of the received signal strength RSSI changes depending on the buried depth of each IC tag 3 from the surface of the upper cover rubber 20.

[0026] When the upper cover rubber 20 is not very worn (when the IC tag 3 is deeply buried), the received signal strength RSSI is small, and as the wear of the upper cover rubber 20 progresses, the buried depth of the IC tag 3 decreases, and the received signal strength RSSI increases. Note that if the buried depth of the IC tag 3 is equal to or greater than a predetermined depth X, the detector 10 does not receive the reply radio wave R2 from the IC tag 3, and the received signal strength RSSI becomes zero. Also, if the wear of the upper cover rubber 20 progresses further and the IC tag 3 is exposed on the surface of the upper cover rubber 20 and then detached from this surface, the detector 10 does not receive the reply radio wave R2 from the IC tag 3, and the received signal strength RSSI also becomes zero.

[0027] This detection system 1 uses the data S in Fig. 7. Therefore, the correlation between the buried depth of the IC tag 3 and the received signal strength RSSI (the data S exemplified in Fig. 7) is grasped by conducting a preliminary test or the like, and input into the calculation device 13.

[0028] The detector 10 employs a commonly available specification that allows wireless communication with passive RFID tags, etc. This allows the IC tag 3 and detector 10 to form an RFID (Radio Frequency Identification) system. The radio frequency used for wireless communication between the IC tag 3 and detector 10 is mainly in the UHF band (a range of 860 MHz to 930 MHz, which varies by country; in Japan, it is 915 MHz to 930 MHz), although the HF band (13.56 MHz) is sometimes used.

[0029] The detector 10 is not limited to being placed on the return side of the conveyor device 14 as in this embodiment, but can also be placed on the carrier side. The distance between the detector 10 and the IC tag 3 (antenna unit 5) when they are closest to each other is set to, for example, within 1 m.

[0030] The arithmetic device 13 is connected to the detector 10 by wire or wirelessly. A known computer or computer server can be used as the arithmetic device 13. Various information such as the reception result (received signal strength RSSI) of the reply radio wave R2 at the detector 10 is input to the arithmetic device 13. In addition, the arithmetic device 13 is input with information unique to each IC tag 3 and information on the embedded position on the conveyor belt 17 (position in the belt width direction, position in the belt thickness direction, and position in the belt length direction). The arithmetic device 13 performs various arithmetic processing based on the input information.

[0031] Next, an example of the procedure for determining the degree of wear of the upper cover rubber 20 using this detection system 1 will be described.

[0032] 1 and 2, in the conveyor device 14, while the conveyor belt 17 is running, transported objects C are thrown onto the surface of the upper cover rubber 20, for example, through a hopper or the like. While the conveyor belt 17 is running, an outgoing radio wave R1 is transmitted from the transmitter 11 of the detector 10 toward each IC tag 3. Each time the IC tag 3 passes the detection position, the transmitter 11 transmits a reply radio wave R2 together with the unique information of that IC tag 3 in response to the transmitted radio wave R1. The receiver 12 of the detector 10 receives the reply radio wave R2 transmitted from each IC tag 3 and the unique information of that IC tag 3.

[0033] The calculation device 13 receives the reception results (received signal strength RSSI) of the reply radio waves R2 from each IC tag 3 received by the detector 10 when each IC tag 3 passes the detection position, and the unique information of each IC tag 3. The calculation device 13 calculates the wear state of the upper cover rubber 20 based on the magnitude of the received signal strength RSSI from each IC tag 3.

[0034] More specifically, the burying depth of each IC tag 3 from the surface of the top cover rubber 20 is sequentially calculated by the computing device 13 based on the data S shown in FIG. 7 and the magnitude of the received signal strength RSSI from each IC tag 3. Since the initial burying depth of each IC tag 3 from the surface of the top cover rubber 20 is known, the amount of wear of the top cover rubber 20 at the location where the IC tag 3 is buried is calculated by subtracting the sequentially calculated burying depth of each IC tag 3 from the initial burying depth. Note that when the received signal strength RSSI from an IC tag 3 that had been gradually increasing becomes zero, it can be assumed that the IC tag 3 has fallen off the top cover rubber 20 as wear of the top cover rubber 20 progresses. Therefore, it is determined that wear of the top cover rubber 20 has progressed to the burying depth of the IC tag 3 at the location where the IC tag 3 was buried.

[0035] As a result, the wear state of the upper cover rubber 20 can be grasped as shown in Figure 8. Data H1 in Figure 8 shows the state of the upper cover rubber 20 before wear, where the layer thickness of the upper cover rubber 20 is the initial layer thickness Hs over almost the entire widthwise range. Data H2 shows the state of the upper cover rubber 20 after the conveyor belt 17 has been running for a predetermined period from the time of data H1, where the center of the upper cover rubber 20 in the widthwise direction is thinner (more worn) than both ends in the widthwise direction. Also, the right side in the widthwise direction is more worn than the left side in the widthwise direction. Data H3 shows the state of the upper cover rubber 20 after the conveyor belt 17 has been running for a predetermined period from the time of data H2, where wear has progressed further over almost the entire widthwise range compared to data H2.

[0036] According to this detection system 1, IC tags 3 are embedded at multiple widthwise and thicknesswise positions, and the strength of the received signal strength RSSI of the reply radio waves R2 returned from each IC tag 3 is used as an index, which is advantageous for accurately grasping details such as the presence or absence of uneven wear on the surface of the upper cover rubber 20, the progress of wear, and the trend of wear. The degree of wear on the surface of the upper cover rubber 20 can be efficiently grasped while the conveyor belt 17 is running, without requiring any complicated work. Furthermore, this detection system 1 is advantageous for achieving a simple, low-cost configuration including multiple IC tags 3 embedded in the conveyor belt 17, a detector 10 that wirelessly communicates with each IC tag 3, and a computing device 13 communicably connected to the detector 10.

[0037] In this embodiment, the IC tags 3 embedded in the upper cover rubber 20 at multiple widthwise and thicknesswise positions are embedded at multiple longitudinal positions spaced apart along the length of the belt, making it possible to accurately ascertain details such as the presence or absence of uneven wear on the surface of the upper cover rubber 20 at each longitudinal position, the progress of wear, and the tendency of wear.

[0038] In this detection system 1, the IC tags 3 embedded at multiple thickness direction positions illustrated in Fig. 4 are arranged at overlapping positions in a plan view of the conveyor belt 17, as illustrated in Fig. 3. Therefore, the IC tag 3 embedded closest to the surface of the upper cover rubber 20 in Fig. 4 (the one embedded deepest) becomes a communication obstacle when other IC tags 3 embedded deeper are wirelessly communicating with the detector 10. As a result, when each IC tag 3 passes the detection position where the detector 10 is arranged, it is possible for only the reply radio wave R2 from the IC tag 3 embedded closest to the surface of the upper cover rubber 20 to be received by the detector 10.

[0039] That is, the detector 10 does not receive the reply radio waves R2 from IC tags 3 that are buried deeper than the IC tag 3 buried closest to the surface of the upper cover rubber 20 in Figure 4. To understand the wear state of the surface of the upper cover rubber 20, it is sufficient to determine the strength of the received signal strength RSSI of the reply radio waves R2 returned from the IC tag 3 buried closest to the surface of the upper cover rubber 20. Therefore, by arranging the IC tags 3 embedded at multiple thickness direction positions so that they overlap in a planar view of the conveyor belt 17, unnecessary reply radio waves R2 are not generated, and the calculation processing load on the calculation device 13 is reduced.

[0040] The IC tags 3 embedded at multiple positions in the thickness direction can also be embedded at positions shifted in the belt longitudinal direction. This specification prevents multiple IC tags 3 from being embedded in a small area, which is advantageous in preventing problems with the upper cover rubber 20 caused by the embedded IC tags 3.

[0041] An embedded body 2 as shown in Figures 9 and 10 can be embedded in the conveyor belt 17 described above. This embedded body 2 has a linear detection element 7 that forms a loop circuit 9 and a passive IC tag 3 connected to this detection element 7. The IC tag 3 that constitutes the embedded body 2 can have the same specifications as the IC tag 3 of the previous embodiment, or can have different specifications.

[0042] The detection element 7 extends over a desired range of the conveyor belt 17 outside the connected IC tag 3 to form a loop circuit 9. The detection element 7 is a conductive linear body, and is formed from a known material such as conductive rubber, conductive paste, or metal wire. The outer diameter (width) of the detection element 7 is, for example, about 0.5 mm to 2.0 mm. The detection element 7 may be a simple wire with a circular cross section, or it may be a flattened linear body (strip-shaped wire).

[0043] The outer peripheral surface of the detection element 7 is covered with an insulator 8, and the detection element 7 is electrically insulated from the outside. The insulator 8 is made of a known insulating material, similar to the insulating layer 6a. One end and the other end in the longitudinal direction of the detection element 7 are each electrically connected to the IC chip 4.

[0044] The detection element 7 (loop circuit 9) extends to a position corresponding to the range where the degree of wear is desired to be grasped in a plan view, and the IC tag 3 is preferably embedded in the widthwise end of the conveyor belt 17. As illustrated in Fig. 11, in this embodiment, the IC tag 3 is disposed at one end in the belt width direction, and the detection element 7 (loop circuit 9) extends from one end to the other end in the belt width direction, generally traversing the entire width of the traction layer 18. The IC tag 3 may be disposed at either one end or the other end in the belt width direction.

[0045] The embedded body 2 can be embedded in the same longitudinal position as each of the IC tags 3 embedded in the upper cover rubber 20 at intervals in the longitudinal direction of the belt, or can be embedded in a position offset in the longitudinal direction of the belt from each of the IC tags 3, as illustrated in Figure 11.

[0046] 12, in the belt thickness direction, the IC tags 3 of the previous embodiment embedded at a plurality of thickness direction positions and the respective embedded bodies 2 are alternately embedded in the upper cover rubber 20. The calculation device 13 receives input of unique information of the IC tags 3 constituting each embedded body 2, element identification information specifying the detection element 7, and information on the embedded position of each embedded body 2 in the conveyor belt 17.

[0047] In this embodiment, as in the previous embodiment, the arithmetic unit 13 determines the state of wear on the surface of the upper cover rubber 20 based on the magnitude of the received signal strength RSSI of the reply radio wave R2 returned from each IC tag 3. Furthermore, while the conveyor belt 17 is running, a transmission radio wave R1 is emitted from the detector 10 toward the IC tag 3 constituting each buried object 2, and each time the IC tag 3 passes the detection position, a reply radio wave R2 is emitted from the IC tag 3 in response to the transmission radio wave R1. Using information from the IC tag 3 transmitted to the detector 10 by the reply radio wave R2, the arithmetic unit 13 determines whether or not the loop circuit 9 is energized. Based on the result of this determination, the state of wear on the surface of the upper cover rubber 20 within the area where the loop circuit 9 is embedded is determined.

[0048] More specifically, if the buried object 2 (loop circuit 9) is sound, electricity is input to the IC chip 4 by the transmitted radio wave R1 received by the antenna unit 5, activating the IC chip 4. When the IC chip 4 is activated, electricity flows from one end of the detection element 7 through the loop circuit 9 to the other end of the detection element 7 and is input to the IC chip 4. This allows the IC chip 4 to determine that the loop circuit 9 is energized. Then, the unique information of the IC tag 3 and the element identification information of the detection element 7 that form the loop circuit 9, which are stored in the IC chip 4, are retrieved. Then, when the antenna unit 5 transmits a reply radio wave R2, the retrieved unique information of the IC tag 3 and the element identification information of the detection element 7 are transmitted by the reply radio wave R2 and received by the receiving unit 12.

[0049] By receiving this return radio wave R2, the receiving unit 12 acquires the information (the unique information of the IC tag 3 and the element identification information of the detection element 7) from the IC chip 4 transmitted by the return radio wave R2. This information acquired by the detector 10 is input to the arithmetic unit 13. The arithmetic unit 13 uses the acquired unique information of each IC tag 3 to identify the buried position on the conveyor belt 17 of the buried object 2 having the IC tag 3 that has been input in advance.

[0050] In this way, the calculation device 13 determines that the detection element 7, for which the element identification information has been input in addition to the unique information of the IC tag 3, is sound, and that the loop circuit 9 formed by this detection element 7 is energized. Since the buried position of the buried body 2 equipped with this detection element 7 is known, the calculation device 13 determines that the wear of the upper cover rubber 20 has not progressed to the position where this buried body 2 is buried.

[0051] If the upper cover rubber 20 wears down to the buried depth of the loop circuit 9, the loop circuit 9 will be exposed to the surface and will soon break. If the loop circuit 9 breaks, even if the IC chip 4 is activated by the transmitted radio wave R1 received by the antenna unit 5, electricity will not flow through the loop circuit 9, and the IC chip 4 will know that the loop circuit 9 is not energized. Therefore, even if the unique information of the IC tag 3 stored in the IC chip 4 is retrieved, the element identification information of the detection element 7 that forms the loop circuit 9 will not be retrieved. Then, when the antenna unit 5 transmits the reply radio wave R2, the retrieved unique information of the IC tag 3 is transmitted by the reply radio wave R2 and received by the receiver 12, but the element identification information of the detection element 7 that forms the loop circuit 9 will not be received by the receiver 12.

[0052] That is, the information acquired by the detector 10 (the unique information of the IC tag 3) is input to the calculation device 13, and the calculation device 13 uses the acquired tag-unique information of each IC tag 3 to identify the previously input buried position of that IC tag 3 on the conveyor belt 17. However, since there is no element identification information for the detection element 7 connected to that IC tag 3, it is determined that the loop circuit 9 formed by that detection element 7 is damaged. That is, in this case, the calculation device 13 determines that wear has progressed to the burial depth of the buried object 2 within the range in which the buried object 2 having that loop circuit 9 is buried.

[0053] In the previous embodiment, the wear state of the upper cover rubber 20 at the positions where each IC tag 3 is embedded can be accurately determined, but the wear state at the positions where no IC tag 3 is embedded is estimated. On the other hand, in this embodiment, the loop circuit 9 extends in the belt width direction, so that the wear state at the positions where no IC tag 3 is embedded in the upper cover rubber 20 can be more reliably determined while suppressing the number of embedded IC tags 3.

[0054] The present disclosure includes the following inventions. Invention 1: A conveyor belt wear detection system including: a plurality of passive IC tags embedded in a conveyor belt; a detector disposed at a predetermined detection position near the conveyor belt and wirelessly communicating with each of the IC tags without contacting the conveyor belt; and a computing device connected to the detector so as to be able to communicate with the detector, the IC tags are embedded at a plurality of widthwise positions spaced apart in the width direction of the conveyor belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the conveyor belt, A conveyor belt wear detection system configured such that radio waves are transmitted from the detector toward each of the IC tags while the conveyor belt is running, and the arithmetic device determines the wear state of the surface of the conveyor belt based on the magnitude of the signal strength received by the detector of the reply radio waves returned from each of the IC tags in response to the transmitted radio waves each time the IC tag passes the detection position. Invention 2: A conveyor belt wear detection system according to invention 1, wherein each of the widthwise positions and each of the thicknesswise positions is set at a plurality of longitudinal positions spaced apart in the longitudinal direction of the conveyor belt. Invention 3: A conveyor belt wear detection system according to invention 1 or 2, wherein the IC tags embedded at the multiple thickness direction positions are arranged in overlapping positions in a planar view of the conveyor belt. Invention 4: embedded bodies each having a linear detection element forming a loop circuit and a passive IC tag connected to the detection element, and the IC tag embedded at each of the thickness direction positions are alternately embedded in the conveyor belt in the thickness direction, the detection elements extend from one end to the other end in the width direction of the conveyor belt, and the IC tag connected to the detection element is disposed at one end or the other end in the width direction of the conveyor belt, The conveyor belt wear detection system according to any one of Inventions 1 to 3 is configured such that, while the conveyor belt is running, a transmission radio wave is emitted from the detector toward the IC tag connected to the detection element, and each time the IC tag passes the detection position, the IC tag transmits a reply radio wave in response to the transmission radio wave and uses the information from the IC tag to send to the detector, to determine whether or not the loop circuit is energized by the arithmetic device, and based on the determination result, the degree of wear on the surface of the conveyor belt within the range where the loop circuit is embedded is grasped. Invention 5: A method for detecting wear of a conveyor belt using a plurality of passive IC tags embedded in the conveyor belt, a detector disposed at a predetermined detection position near the conveyor belt and wirelessly communicating with each of the IC tags without contacting the conveyor belt, and a computing device connected to the detector so as to be able to communicate with the detector, The IC tags are embedded at a plurality of widthwise positions spaced apart in the width direction of the conveyor belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the conveyor belt, A conveyor belt wear detection method in which, while the conveyor belt is running, the detector emits radio waves toward each of the IC tags, and each time each of the IC tags passes the detection position, the detector receives the signal strength of the reply radio waves returned from each of the IC tags in response to the emitted radio waves, and the arithmetic device determines the wear state of the surface of the conveyor belt based on the magnitude of each received signal strength. [Explanation of symbols]

[0055] 1. Detection System 2 Buried bodies 3. IC tags 4 IC chip 5 Antenna section 6 PCB 6a Insulating layer 7. Detector element 8. Insulators 9 Loop Circuit 10 Detector 11. Communications Department 12 Receiving unit 13 Arithmetic unit 14 Conveyor equipment 15a, 15b pulleys 16 Support roller 17 Conveyor Belt 18 Cardiac layer 19 Steel Cord 20 Upper cover rubber 21 Lower cover rubber C. Transported goods

Claims

1. A conveyor belt wear detection system including a plurality of passive IC tags embedded in a conveyor belt, a detector disposed at a predetermined detection position near the conveyor belt and wirelessly communicating with each of the IC tags without contacting the conveyor belt, and a computing device connected to the detector so as to be able to communicate with the detector, the IC tags are embedded at a plurality of widthwise positions spaced apart in the width direction of the conveyor belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the conveyor belt, A conveyor belt wear detection system configured such that radio waves are emitted from the detector toward each of the IC tags while the conveyor belt is running, and the computing device determines the wear state of the surface of the conveyor belt based on the magnitude of the signal strength received by the detector of the reply radio waves returned from each of the IC tags in response to the emitted radio waves each time the IC tag passes the detection position.

2. 2. The conveyor belt wear detection system according to claim 1, wherein each of the widthwise positions and each of the thicknesswise positions is set at a plurality of longitudinal positions spaced apart in the longitudinal direction of the conveyor belt.

3. 3. The conveyor belt wear detection system according to claim 1, wherein the IC tags embedded at the plurality of thickness direction positions are arranged at overlapping positions in a plan view of the conveyor belt.

4. embedded bodies each having a linear detection element forming a loop circuit and a passive IC tag connected to the detection element, and the IC tag embedded at each of the thickness direction positions are alternately embedded in the conveyor belt in the thickness direction, the detection elements extend from one end to the other end in the width direction of the conveyor belt, and the IC tag connected to the detection element is disposed at one end or the other end in the width direction of the conveyor belt, 3. The conveyor belt wear detection system according to claim 1, wherein the detector emits radio waves toward the IC tag connected to the detection element while the conveyor belt is running, and each time the IC tag passes the detection position, the IC tag emits reply radio waves in response to the transmitted radio waves and uses the information from the IC tag to send to the detector, whereby the arithmetic unit determines whether or not the loop circuit is energized, and based on the determination result, the degree of wear on the surface of the conveyor belt within the area where the buried object is buried is grasped.

5. A method for detecting wear of a conveyor belt using a plurality of passive IC tags embedded in the conveyor belt, a detector disposed at a predetermined detection position near the conveyor belt and wirelessly communicating with each of the IC tags without contacting the conveyor belt, and a computing device connected to the detector so as to be able to communicate with the detector, The IC tags are embedded at a plurality of widthwise positions spaced apart in the width direction of the conveyor belt and at a plurality of thicknesswise positions spaced apart in the thickness direction of the conveyor belt, A conveyor belt wear detection method in which, while the conveyor belt is running, the detector emits radio waves toward each of the IC tags, and each time each of the IC tags passes the detection position, the detector receives the signal strength of the reply radio waves returned from each of the IC tags in response to the emitted radio waves, and the arithmetic device determines the wear state of the surface of the conveyor belt based on the magnitude of each received signal strength.

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