JP7407043B2 - crack detection label set - Google Patents

Description

The present invention relates to a crack detection label set that is attached to an adherend to detect cracks that occur in the adherend.

In recent years, RFID labels capable of non-contact communication have been used to detect cracks in structures that serve as adherends. This type of RFID label takes advantage of the fact that if a crack occurs in the adherend while it is attached to the adherend, the antenna or wiring will be disconnected. Based on this, it is determined whether or not cracks have occurred in the adherend. Patent Document 1 discloses that two antennas with different frequencies are used, and when a crack occurs in the adherend, one of the antennas is disconnected, and the change in frequency is detected. A configuration for detecting whether a crack has formed is disclosed.

Patent No. 4812095

As for the above-mentioned adherends, the adhering surface to which the label is attached may be made of metal. In that case, if an antenna or wiring whose conduction state changes due to a crack in the adherend becomes electrically connected to the adherend, it becomes impossible to accurately detect the occurrence of a crack in the adherend. Therefore, the targets for which cracks can be detected are limited. In addition, even if a paint film is laminated on the adhesive surface of the adherend to which the label is pasted, the paint film may become locally thin or peel off due to aging, etc. There may be cases where Even in that case, conduction occurs between the antenna or the wiring and the adherend, making it impossible to accurately detect the occurrence of a crack in the adherend.

In addition, in the antenna disclosed in Patent Document 1, the antenna, which breaks when a crack occurs in the adherend, is covered with a covering material made of a dielectric material such as glass or plastic. When used as a coating material, if the crack that occurs in the adherend is a minute crack with a crack width of about 100 μm, for example, the coating material is unlikely to follow the crack and break. Therefore, by the time a crack in the adherend is detected, the deterioration of the adherend has already progressed considerably, making it impossible to detect cracks in the adherend at an early stage. There is a risk that it will be too late to respond to the occurrence of cracks.

Furthermore, as mentioned above, in order to non-contactly communicate the continuity status of antennas and wiring, a non-contact communication means consisting of a communication antenna and an IC chip connected to it is required. There is a problem in that sufficient space is required to install a non-contact communication means nearby, and if there is an obstacle near the crack detection location, the label itself cannot be affixed. In addition, if there is an obstacle such as a metal object that obstructs non-contact communication in the vicinity of the crack detection location, accurate non-contact communication of the continuity status of the antenna or wiring may not be possible. There is a problem in that it is no longer possible to accurately detect the occurrence of a crack.

The present invention has been made in view of the problems of the conventional techniques as described above, and even if an obstacle exists near the crack detection location, it is possible to detect the occurrence of a crack in the adherend. The purpose of the present invention is to provide a crack detection label set that can detect cracks accurately and early.

In order to achieve the above object, the present invention has the following features:
A crack detection label set affixed to an adherend to detect cracks generated in the adherend, the set comprising:
a first label affixed across the crack detection location;
a second label affixed to the adherend while being electrically connected to the first label;
The first label is
A metal wiring layer with both ends open,
a non-conductive adhesive layer laminated on one surface of the metal wiring layer,
The second label is
a base material,
a non-conductive adhesive layer laminated on one side of the base material;
A communication antenna and two auxiliary wirings formed on the base material,
Disposed on the base substrate to be connected to the communication antenna and auxiliary wiring, detects the conduction state of the metal wiring layer via the auxiliary wiring, and non-contact transmits the detection result via the communication antenna. and a detection means for
Each of the two auxiliary wirings has a joint portion with an exposed end opposite to the end connected to the detection means,
Both ends of the metal wiring layer and the joint portions of the two auxiliary wirings are electrically connected.

In the present invention configured as described above, when a crack occurs in the adherend while the first label is pasted across the crack detection location on the adherend, the first label follows the crack and the first label The label is broken, and the metal wiring layer provided on the first label is disconnected. At this time, the first label is composed of a metal wiring layer and a non-conductive adhesive layer laminated on one side of the metal wiring layer, and is attached to the adherend by the non-conductive adhesive layer. , the first label easily breaks following the crack, and even if the adhering surface of the adherend is made of metal, there is no electrical continuity between the adherend and the metal wiring layer. . The conduction state of the metal wiring layer of the first label is detected by the detection means of the second label via two auxiliary wirings, and is transmitted in a non-contact manner via the communication antenna of the second label. However, each of the two auxiliary wires has a joint where the end opposite to the end connected to the detection means is exposed, and this joint is electrically connected to both ends of the metal wiring layer. Since the metal wiring layer and the detection means are electrically connected via the auxiliary wiring, it is possible to connect the metal wiring layer and the detection means electrically through the auxiliary wiring. However, if the first label has a shape and metal wiring layer pattern that corresponds to the arrangement, the second label, which has a communication antenna and detection means, will not be affected by communication or physical interference due to obstacles. Can be pasted to the area.

Furthermore, if a slit is formed in the metal wiring layer of the first label, extending from one side edge toward the other side edge and terminating before reaching the other side edge, it is possible to When a crack occurs in the body, the metal wiring layer follows the crack and becomes easily disconnected.

Further, if the second label has a non-conductive member interposed between the base material and the non-conductive adhesive layer at least in the region facing the communication antenna and the detection means, the communication antenna The distance between the detecting means and the adherend can be widened by a non-conductive member, and even if the adherend is made of metal, the distance between the detecting means and the adherend can be widened by using a non-conductive member. It is possible to reduce the influence of

Further, if the joint portion has a shape that exposes the base material within the region where the joint portion is provided, the bonding strength between both ends of the metal wiring layer and the joint portion is improved.

According to the present invention, the first label has a metal wiring layer that is disconnected when a crack occurs in the adherend, and the second label has a communication antenna and detection means that transmits the conduction state of the metal wiring layer in a non-contact manner. Since the label is constructed as a separate body and these are electrically connected, even if there is an obstacle near the crack detection point, it is possible to accurately and accurately detect the occurrence of a crack in the adherend. Can be detected early.

Further, in the case where a slit is formed in the metal wiring layer of the first label, extending from one side edge toward the other side edge and terminating before reaching the other side edge, When a crack occurs in the adherend, the metal wiring layer can easily follow the crack and break.

In addition, when the second label has a non-conductive member interposed between the base material and the non-conductive adhesive layer at least in the region facing the communication antenna and the detection means, The distance between the antenna and the detecting means and the adherend can be widened by using a non-conductive member. This can make it difficult for the wearer to be affected.

Further, in the case where the bonding portion has a shape that exposes the base material within the region where the bonding portion is provided, the bonding strength between both ends of the metal wiring layer and the bonding portion can be improved.

1 is a diagram showing an embodiment of the crack detection label set of the present invention, (a) is a top view, (b) is a side view, (c) is a top view of the RF label alone, and (d) is the detection label alone. FIG. FIG. 2 is a side view for explaining a method of attaching the crack detection label set shown in FIG. 1 to an adherend. FIG. 2 is a top view for explaining a method of attaching the crack detection label set shown in FIG. 1 to an adherend. FIG. 4 is a diagram for explaining the effect when a crack occurs in the detection area when the crack detection label set shown in FIG. 1 is attached to the cart as shown in FIGS. 2 and 3. FIG. FIG. 2 is a diagram illustrating an example of a system for detecting cracks generated in a truck using the crack detection label set shown in FIG. 1. FIG. 6 is a flowchart illustrating a method for detecting cracks generated in a truck using the crack detection label set shown in FIG. 1 in the system shown in FIG. 5. FIG. 2 is a diagram for explaining the effect of providing a slit in the wiring layer of the detection label shown in FIG. 1. FIG. FIG. 7 is a diagram showing another embodiment of the crack detection label set of the present invention, in which (a) is a top view, (b) is a side view, (c) is a top view of the RF label alone, and (d) is a detection label. It is a top view of a single unit.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of a crack detection label set of the present invention, in which (a) is a top view, (b) is a side view, (c) is a top view of the RF label 20 alone, and (d) is a top view. ) is a top view of the detection label 10 alone.

As shown in FIG. 1, this embodiment is a crack detection label set 1 configured by a detection label 10 and an RF label 20 pasted together with a conductive adhesive layer 30.

The detection label 10 is the first label of the present invention. The detection label 10 is constructed by laminating a non-conductive adhesive layer 12 on the entire surface of one side of a meander-shaped wiring layer 11 serving as a metal wiring layer. The wiring layer 11 is made of copper foil or the like, and extends in a meandering shape with a constant width so that both ends serve as joint portions 15 and the joint portions 15 are connected. Slits 13a and 13b are formed in the wiring layer 11, including the non-conductive adhesive layer 12, passing through the front and back sides. The slits 13a and 13b are configured such that the slit 13a extends from one side edge of the wiring layer 11 as a starting point, the slit 13b extends from the other side edge of the wiring layer 11 as a starting point, and the end portions of the slits 13a and 13b are connected to each other. They are formed so as to face each other with a gap 14 in between. A conductive adhesive layer 30 is laminated on the surface of the joint 15 of the wiring layer 11 opposite to the surface on which the non-conductive adhesive layer 12 is laminated. An RF label 20 is attached.

The RF label 20 serves as the second label of the present invention. In the RF label 20, a protective layer 27 made of a non-conductive material and a spacer 40 are laminated on one side of a base substrate 21 made of a film or the like, and a non-conductive material is laminated to cover the protective layer 27 and the spacer 40. The conductive adhesive layer 28 is laminated. Two communication antennas 23 and two auxiliary wirings 24 are formed of copper foil or the like on the laminated surface of the base substrate 21 with the protective layer 27, and are connected to these antennas 23 and auxiliary wirings 24. An IC chip 22 is mounted.

The IC chip 22 serves as a detection means in the present invention. The IC chip 22 is provided with two antenna terminals (not shown) and two crack detection terminals (not shown), and the surface on which these antenna terminals and crack detection terminals are provided serves as the mounting surface. The protective layer 27 is mounted on the surface of the base material 21 that is laminated with the protective layer 27 . The antenna terminals of the IC chip 22 are each connected to the antenna 23, and the crack detection terminals of the IC chip 22 are connected to one end of each of the two auxiliary wirings 24. The auxiliary wiring 24 extends from the end connected to the IC chip 22, and has a joint 25 at the opposite end. The IC chip 22 detects the resistance values of the wiring layer 11 and the auxiliary wiring 24 by passing a current generated by electric power obtained through non-contact communication through the antenna 23 to the wiring layer 11 through the auxiliary wiring 24, and calculates the resistance. The conduction state of the wiring layer 11 is detected based on the value, and the detection result is converted into digital information and transmitted via the antenna 23 in a non-contact manner. An example of the IC chip 22 is UCODE G2iM+ manufactured by NXP.

Slits 26a and 26b passing through the front and back sides of the base substrate 21, including the protective layer 27 and the non-conductive adhesive layer 28, are formed from one edge to the opposite edge, avoiding the auxiliary wiring 24. has been done.

The protective layer 27 is made of a film or the like, and is laminated on the surface of the base substrate 21 on which the antenna 23 and the auxiliary wiring 24 are formed so that the joint portion 25 of the auxiliary wiring 24 is exposed.

The spacer 40 serves as a non-conductive member in the present invention. The spacer 40 is made of a soft non-metallic material such as foamed acrylic resin, and is arranged between the antenna 23 and the IC chip 22 on the surface of the protective layer 27 opposite to the laminated surface with the base material 21. It is interposed between the base material 21 and the non-conductive adhesive layer 28 by being laminated in a region facing the .

Since the detection label 10 and the RF label 20 configured in this way have the joint part 25 of the auxiliary wiring 24 of the RF label 20 exposed, the joint part 25 and the joint part which becomes both ends of the wiring layer 11 are connected to each other. 15 are adhered to each other by a conductive adhesive layer 30 laminated on the joint portion 15, whereby the auxiliary wiring 24 and the wiring layer 11 are electrically connected.

Below, a method of using the crack detection label set 1 configured as described above and its operation will be explained.

FIG. 2 is a side view for explaining a method of attaching the crack detection label set 1 shown in FIG. 1 to an adherend, and FIG. FIG. 3 is a top view for explaining a method of adhering to the body.

Before the crack detection label set 1 shown in FIG. 1 is attached to the adherend for crack detection, the detection label 10 and the RF label 20 are electrically conductive, as shown in FIG. 2(a). The detection label 10 is not attached by the adhesive layer 30 but is a separate body, and release papers 16a and 16b are releasably attached to the front and back sides of the detection label 10, and a release paper 29 is attached to the back side of the RF label 20. is removably attached.

When detecting cracks in the adherend using the crack detection label set 1 in this state, first peel off the release paper 16b of the detection label 10, and as shown in FIGS. 2(b) and 3(a). A detection label 10 is pasted with a non-conductive adhesive layer 12 so that the area where the slits 13a and 13b of the wiring layer 11 are formed straddles the detection area 2a, which is a crack detection point, of the cart 2, which is an adherend. wear it. At this time, the detection label 10 has a wiring layer 11 made of copper foil, but since the non-conductive adhesive layer 12 is laminated on the entire surface of the wiring layer 11 that is attached to the trolley 2, Even if the adhesive surface of the detection label 1 is made of metal or the coating film is thin, electrical conduction between the wiring layer 11 and the trolley 2 can be avoided.

Next, as shown in FIGS. 2(c) and 3(b), the release paper 16a is peeled off from the detection label 10 affixed to the cart 2 to expose the conductive adhesive layer 30.

Next, the release paper 29 of the RF label 20 is peeled off, and as shown in FIG. 2(d) and FIG. The RF label 20 is superimposed on the detection label 10 affixed to the trolley 2 so that the joint portions 25 thereof face each other, and the RF label 20 is affixed to the trolley 2 with a non-conductive adhesive layer 28 . As a result, the joint 15 of the wiring layer 11 and the joint 25 of the auxiliary wiring 24 are attached via the conductive adhesive layer 30 laminated on the joint 15 of the wiring layer 11, and the wiring layer 11 and the auxiliary The wiring 24 is now electrically connected.

After pasting the crack detection label set 1 on the trolley 2 as described above, protective paint is applied to the region of the trolley 2 to which the crack detection label set 1 has been pasted, covering the crack detection label set 1. This will prevent the crack detection label set 1 from peeling off from the truck 2 and falling apart when the vehicle having the truck 2 is running.

FIG. 4 is a diagram for explaining the effect when a crack occurs in the detection area 2a when the crack detection label set 1 shown in FIG. 1 is attached to the trolley 2 as shown in FIGS. 2 and 3. It is a diagram.

When the crack detection label set 1 shown in FIG. 1 is attached to the trolley 2 as shown in FIGS. 2 and 3 and no cracks are generated in the detection area 2a, as shown in FIG. In addition, the wiring layer 11 is not disconnected, and the wiring layer 11 is in a conductive state between the two joint parts 15.

When the crack detection label set 1 shown in FIG. 1 is attached to the trolley 2 as shown in FIGS. 2 and 3, as shown in FIG. When a crack 2b occurs in the detection area 2a of the truck 2, a pulling force is applied to both sides of the detection label 10 attached to the detection area 2a through the crack 2b. Then, in the area of the wiring layer 11 of the detection label 10 facing the detection area 2a, there is a slit 13a extending from one side edge of the wiring layer 11 as a starting point, and a slit 13a extending from the other side edge of the wiring layer 11 as a starting point. Since the slits 13b extending as slits 13b are formed so as to face each other with the ends of the slits 13a and 13b facing each other across the gap 14 without being connected to each other, the wiring layer is The portion of the gap 14 in the wiring layer 11 follows the crack 2b and breaks together with the non-conductive adhesive layer 12, whereby the wiring layer 11 is disconnected between the two joints 15 and becomes non-conductive.

Below, a specific method of detecting the crack 2b generated in the truck 2 using the above-mentioned effect will be described.

FIG. 5 is a diagram showing an example of a system for detecting a crack 2b generated in the trolley 2 using the crack detection label set 1 shown in FIG. 1.

As shown in FIG. 5, a system for detecting cracks 2b generated in the trolley 2 using the crack detection label set 1 shown in FIG. 1 is capable of non-contact communication with the crack detection label set 1. A system can be considered that includes a reader/writer 5 serving as a reading means and a management personal computer 6 serving as a processing means connected to the reader/writer 5 via wire or wirelessly. It is also conceivable to use a handy terminal with built-in processing means as well as reading means as the reader/writer, in which case a management personal computer would be unnecessary.

FIG. 6 is a flowchart illustrating a method for detecting a crack 2b generated in a truck 2 using the crack detection label set 1 shown in FIG. 1 in the system shown in FIG.

In the crack detection label set 1 shown in FIG. 1, when the reader/writer 5 is brought close to the crack detection label set 1 and the reader/writer 5 detects the crack detection label set 1 (step 1), 5, power is supplied to the crack detection label set 1, and a command to detect the conduction state of the wiring layer 11 and transmit the detection result is transmitted to the crack detection label set 1 (step 2). ). At this time, since the spacer 40 made of non-metal is laminated on the area facing the antenna 23 and the IC chip 22 on the surface of the protective layer 27 opposite to the laminated surface with the base substrate 21, the antenna 23 and the IC chip 22 and the cart 2 can be widened by the spacer 40, and even when the crack detection label set 1 is attached to the metal cart 2, the crack detection label set 1 and the crack detection label set 1 can be separated by the reader/writer 5. When performing non-contact communication between the two, it is possible to make it difficult for the trolley 2 to have an influence.

The power supplied from the reader/writer 5 is obtained by the crack detection label set 1, and the command transmitted from the reader/writer 5 is sent to the IC chip 22 via the antenna 23 of the RF label 20 that constitutes the crack detection label set 1. When received (step 3), current is supplied to the auxiliary wiring 24 by the power supplied from the reader/writer 5.

The wiring layer 11 of the detection label 10 is electrically connected to the auxiliary wiring 24 via the conductive adhesive layer 30 as described above, so that the wiring layer 11 of the detection label 10 is electrically connected to the auxiliary wiring 24 by the power supplied from the reader/writer 5. A current is supplied to the wiring layer 11 .

In the IC chip 22, the conduction state of the wiring layer 11 is detected by detecting the resistance values of the wiring layer 11 and the auxiliary wiring 24 (step 4). Here, if the crack detection label set 1 is affixed to the trolley 2 as shown in FIGS. 2 and 3 and there is no crack in the detection area 2a of the trolley 2, it means that the wiring layer 11 is not broken. Since the joint portions 15 of the wiring layer 11 are electrically connected and in a conductive state, the resistance value formed by the wiring layer 11 and the auxiliary wiring 24 is detected in the IC chip 22.

In the IC chip 22, when the detected resistance value is the resistance value consisting of the wiring layer 11 and the auxiliary wiring 24, it is determined that the wiring layer 11 is in a conductive state, and the determination result is determined as the resistance value of the wiring layer 11 and the auxiliary wiring 24. As a result of the detection of the conduction state, the digital information is converted into digital information and transmitted contactlessly to the reader/writer 5 via the antenna 23 (step 5). Note that when the wiring layer 11 is in a non-conductive state, the resistance value detected by the IC chip 22 becomes almost infinite as described later. Instead of the resistance value formed by the wiring layer 11 and the auxiliary wiring 24, a value below a certain threshold value may be used as the resistance value for determining that the wiring layer 11 and the auxiliary wiring 24 exist.

On the other hand, if the crack detection label set 1 is attached to the trolley 2 and a crack 2b occurs in the detection area 2a of the trolley 2 as shown in FIG. 4(b), the wiring layer 11 may be broken. , the two joint portions 15 of the wiring layer 11 are not electrically connected, and the wiring layer 11 is in a non-conductive state. In this state, even if a current is supplied to the wiring layer 11 via the auxiliary wiring 24 by the power supplied from the reader/writer 5, the wiring layer 11 will not be current because the wiring layer 11 is in a non-conductive state. does not flow, and as a result, the resistance value detected in the IC chip 22 becomes almost infinite.

In the IC chip 22, when the detected resistance value is almost infinite, it is determined that the wiring layer 11 is in a non-conductive state, and the determination result is converted into digital information as the result of detecting the conductive state of the wiring layer 11. and is transmitted to the reader/writer 5 via the antenna 23 in a non-contact manner. Note that when the wiring layer 11 is in a non-conducting state, the resistance value detected by the IC chip 22 is almost infinite, so the IC chip 22 determines that the wiring layer 11 is in a non-conducting state. The resistance value may not be approximately infinite, but may be greater than a certain threshold value, which is greater than the resistance value formed by the wiring layer 11 and the auxiliary wiring 24.

In this manner, the reader/writer 5 transmits the conduction state of the wiring layer 11 detected by the crack detection label set 1 via the antenna 23 in a non-contact manner.

When the detection result transmitted contactlessly from the crack detection label set 1 to the reader/writer 5 as described above is received by the reader/writer 5 (step 6), the detection result received by the reader/writer 5 is used for management. The data is transferred to the personal computer 6 (step 7).

When the detection results transferred from the reader/writer 5 are received by the management PC 6 (step 8), the crack detection label set 1 is sent to the reader/writer 5 in a non-contact manner in the management PC 6. Based on the detection results transferred to step 6, it is determined whether a crack 2b has occurred in the detection area 2a of the truck 2 (step 9). Specifically, in the detection results transferred from the reader/writer 5 to the management computer 6, if the wiring layer 11 is in a conductive state, it is determined that there is no crack 2b in the detection area 2a of the trolley 2, and the wiring If the layer 11 is in a non-conductive state, it is determined that a crack 2b has occurred in the detection area 2a of the truck 2.

The crack detection label set 1 configured in this manner can be used, for example, to detect cracks in the bogie 2 of a railway vehicle. In that case, if the spacer 40 is made of a soft material such as foamed acrylic resin, even if the crack detection label set 1 is blown away by the wind or falls off due to vibration while the railway vehicle is running, it will not cause cracks. Damage caused by the detection label set 1 hitting a human body or the like can be reduced.

In this manner, in this embodiment, the detection label 10 has the wiring layer 11 that is disconnected when a crack occurs in the trolley 2, and the RF label has the antenna 23 and IC chip 22 that transmit the conduction state of the wiring layer 11 in a non-contact manner. 20 are constructed separately and are electrically connected via the conductive adhesive 30, so even if there are obstacles near the crack detection location, it is easy to place them at the work site etc. By using the detection label 10 having a shape and a pattern of the wiring layer 11 according to the above, the RF label 20 having the antenna 23 and the IC chip 22 can be attached to an area where communication or physical interference will not occur due to obstacles. Therefore, it is possible to accurately and quickly detect that a crack has occurred in the trolley 2. In addition, by preparing the detection label 10 having a shape and a pattern of the wiring layer 11 according to the arrangement of obstacles, etc. at the crack detection location, it is possible to detect the arrangement of obstacles, etc. at the crack detection location. However, the RF label 20 can be of one type, and thereby the communication characteristics of non-contact communication with the reader/writer will vary, making it difficult to adjust the resonance frequency and the like. Furthermore, since the detection label 10 and the RF label 20 are configured to be electrically bonded via the conductive adhesive layer 30 laminated on the wiring layer 11 of the detection label 10, the detection label 10 and the RF label 20 are can be easily joined at the work site.

Here, the effect of providing the slits 13a and 13b in the wiring layer 11 will be explained.

In crack detection label set 1 shown in FIG. It is necessary to disconnect.

On the other hand, when using metal foil as the wiring layer 11, the metal foil must have a certain width (for example, 6 mm), otherwise it will not be processed into a meandering shape, for example, as in the wiring layer 11 shown in FIG. difficult to do. Moreover, if the width of the foil is too narrow, handling when attaching the detection label 10 to the trolley 2 will be poor and it is not practical. However, as the width of the foil increases, the rigidity of the wiring layer 11 increases, making it impossible to break the wiring even with minute displacements or forces.

FIG. 7 is a diagram for explaining the effect of providing slits 13a and 13b in the wiring layer 11 of the detection label 10 shown in FIG. 1.

Here, we used a copper foil with a length of 50 mm and measured the crack width when the copper foil broke by changing its width. As shown in Figure 7 (a), when the width of the copper foil was 1 mm, However, regardless of whether the film thickness is 35 μm or 18 μm, a crack with a width of 400 μm or less will not break the copper foil, and therefore a crack with a width of 400 μm or less cannot be detected. When the width of the copper foil is 6 mm, even cracks with a width exceeding 2 mm cannot be detected without breaking.

On the other hand, when the slits 13a and 13b are formed through the gap 14 as in the detection label 10 shown in FIG. When a copper foil with a length of 50 mm and a width of 6 mm is used, as shown in FIG. 7(b), the part of the void 14 follows the crack 2b and breaks. If the width of the gap 14 is 1 mm, it will break to follow the minute crack 2b having a width of about 100 μm.

In this way, by forming the slits 13a and 13b through the gap 14 like the detection label 10 shown in FIG. The gap 14 portion follows the crack 2b and ruptures from the end, and even a crack with a minute width can be detected. Note that, as in the detection label 10 shown in FIG. Even if the wiring layer 11 and the non-conductive adhesive layer 12 are not formed so that they extend as a starting point and face each other across the gap 14 without being connected to each other, the ends on the end point side are not connected to each other. The same effect as described above can be obtained if a slit is formed that extends from one side edge toward another side edge and terminates before reaching the other side edge. Note that in order to obtain the above effect, it is not necessary that the slits 13a and 13b penetrate the front and back sides of the wiring layer 11 and the non-conductive adhesive layer 12 as shown in FIG. It suffices if it penetrates both the front and back sides. However, if the slits 13a and 13b penetrate the front and back sides of the wiring layer 11 and the non-conductive adhesive layer 12, if a crack 2b occurs in the detection area 2a as shown in FIG. 4(b), the detection label 10 follows the crack 2b and breaks easily. In addition, if the slits 13a and 13b are not formed in the non-conductive adhesive layer 12, the material of the non-conductive adhesive layer 12 may be It is conceivable to adjust the thickness appropriately.

Note that in this embodiment, a conductive adhesive layer 30 is laminated on the wiring layer 11 of the detection label 10, and the detection label 10 and the RF label 20 are electrically bonded via this conductive adhesive layer 30. Although the configuration has been described as an example, a conductive adhesive layer 30 is laminated on the joint 25 of the auxiliary wiring 24 of the RF label 20, and the detection label 10 and the RF label 20 are connected via the conductive adhesive layer 30. It is also possible to have a configuration in which the two are electrically connected. Furthermore, instead of electrically joining the detection label 10 and the RF label 20 via the conductive adhesive layer 30, it is also possible to electrically join them by welding using heat or ultrasonic waves. However, by electrically bonding the detection label 10 and the RF label 20 via the conductive adhesive layer 30, the bonding surfaces of the detection label 10 and the RF label 20 can be easily fixed and electrically bonded. Furthermore, by forming the conductive adhesive layer 30 on either of the bonding surfaces of the detection label 10 and the RF label 20 in advance, the detection label 10 and the RF label 20 can be bonded more easily. It becomes possible.

Further, in this embodiment, the wiring layer 11 is made of copper foil, but the wiring layer 11 may be made of a metal foil other than copper foil. When metal foil is used as the wiring layer 11, the film thickness is more uniform than when the wiring layer 11 is formed using conductive ink, etc., so even when the object to which the detection label 10 is attached has a three-dimensional shape, etc. , the detection performance becomes stable. In particular, the detection area 2a of the trolley 1 is mainly around the welded part of the iron plate, and since the surrounding area is often almost three-dimensional, it is preferably made of metal foil.

Further, in this embodiment, the conductive adhesive layer 30 is laminated on the joint portion 15 of the wiring layer 11, but the surface of the wiring layer 11 on which the non-conductive adhesive layer 12 is laminated. The conductive adhesive layer 30 may be laminated on the entire surface of the opposite side. However, in that case, the wiring layer 11 becomes difficult to break following the cracks 2b generated in the bogie 2, and dust such as iron powder generated as the vehicle having the bogie 2 runs is likely to adhere thereto.

Furthermore, in this embodiment, the wiring layer 11 has a meandering shape. However, when the detection label 10 is attached to the detection area 2a of the trolley 2, Any shape is sufficient as long as the region between the joint portions 15 at both ends of the sensor 11 straddles the detection area 2a. However, if the wiring layer 11 has a linear shape that reciprocates in a direction intersecting the direction connecting the joints 15 at both ends of the wiring layer 11, the area where cracks can be detected can be increased.

In addition, in order to facilitate workability when pasting the detection label 10 and the RF label 20 using the conductive adhesive layer 30, the outer shape of the detection label 10 is visually checked in the area of the RF label 20 that overlaps with the detection label 10. It is possible to create a cutout to enable this, or to change the shape of the RF label 20 itself so that when the RF label 20 is superimposed on the detection label 10, the outer shape of the detection label 10 is visible. It will be done.

(Other embodiments)
FIG. 8 is a diagram showing another embodiment of the crack detection label set of the present invention, in which (a) is a top view, (b) is a side view, (c) is a top view of the RF label 120 alone, ( d) is a top view of the detection label 10 alone.

As shown in FIG. 8, this embodiment is a crack detection label set 101 in which the configuration of the RF label 120 is different from that shown in FIG. In the RF label 120 in this embodiment, the joint portion 125 at the end of the auxiliary wiring 24 is configured by a plurality of square conductive regions regularly arranged vertically and horizontally. As a result, when the detection label 10 and the RF label 120 are attached using the conductive adhesive layer 30, the square conductive area and the base substrate 21 are provided in the area of the RF label 120 that faces the conductive adhesive layer 30. There will be a checkerboard pattern of alternating exposed square areas. Note that the square conductive regions are electrically connected to each other, and thereby all the conductive regions are electrically connected to the auxiliary wiring 24.

In the crack detection label set 101 configured in this way, when the detection label 10 and the RF label 120 are attached with the conductive adhesive layer 30, the conductive adhesive layer 30 faces not only the conductive region formed by the joint 125 but also the exposed base material 21. Therefore, if the base material 21 is made of a resin material such as a film as described above, the conductive region The bonding strength of the adhesive layer 30 can be improved.

Note that the shape of the joint 125 is not limited to one in which a plurality of square conductive regions are regularly arranged vertically and horizontally; , a mesh shape, a stripe shape, etc. may be used as long as it faces not only the conductive region formed by the joint portion 125 but also the exposed base material 21. However, all of the plurality of conductive regions need to be electrically connected to the auxiliary wiring 24.

1,101 Crack detection label set 2 Cart 2a Detection area 2b Crack 5 Reader/writer 6 Management computer 10 Detection label 11 Wiring layer 11a Disconnection 12, 28 Non-conductive adhesive layer 13a, 13b, 26a, 26b Slit 14 Gap 15, 25,125 Joint portion 16a, 16b, 29 Release paper 20,120 RF label 21 Base material 22 IC chip 23 Antenna 24 Auxiliary wiring 27 Protective layer 30 Conductive adhesive layer 40 Spacer

Claims (4)

A crack detection label set affixed to an adherend to detect cracks generated in the adherend, the set comprising:
a first label affixed across the crack detection location;
a second label affixed to the adherend while being electrically connected to the first label;
The first label is
A metal wiring layer with both ends open,
a non-conductive adhesive layer laminated on one surface of the metal wiring layer,
The second label is
a base material,
a non-conductive adhesive layer laminated on one side of the base material;
A communication antenna and two auxiliary wirings formed on the base material,
Disposed on the base substrate to be connected to the communication antenna and auxiliary wiring, detects the conduction state of the metal wiring layer via the auxiliary wiring, and non-contact transmits the detection result via the communication antenna. and a detection means for
Each of the two auxiliary wirings has a joint portion with an exposed end opposite to the end connected to the detection means,
A crack detection label set in which both ends of the metal wiring layer and the joint portion of the two auxiliary wirings are electrically connected. The crack detection label set according to claim 1,
The first label is a crack detection device in which a slit is formed in the metal wiring layer, extending from one side edge toward the other side edge and terminating before reaching the other side edge. label set. The crack detection label set according to claim 1 or 2,
The second label has a crack in which a non-conductive member is interposed between the base substrate and the non-conductive adhesive layer at least in a region facing the communication antenna and the detection means. Detection label set. The crack detection label set according to any one of claims 1 to 3,
The crack detection label set, wherein the joint portion has a shape that exposes the base material within a region where the joint portion is provided.

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