Anomaly detection device for the surface of a rotating body

Abstract

To provide a rotating body abnormality detection device that can accurately detect and communicate abnormalities in rotating bodies such as rollers and pulleys in a conveyor system. [Solution] A first circuit X is configured by connecting a detection cord 8, which is connected by wiring to a lagging material 5 provided on the entire outer circumference of a rotating body such as a pulley P, to a rotating body-side coil 9. A second circuit Y is configured by providing a stationary coil 10 on the stationary side that can supply power to the rotating body-side coil 9 by electromagnetic induction. When the continuity of the detection cord 8 is interrupted, the first circuit X sends a detection signal to the circuit, and the second circuit Y receives the detection signal from the first circuit X by electromagnetic induction and detects the disconnection of the detection cord 8. This is an abnormality detection device for the surface of a rotating body.

Description

Technical Field

[0001] This invention relates to a device for detecting abnormalities such as abnormal wear on the surface of rotating bodies such as pulleys and rollers of a belt conveyor.

Background Art

[0002] As is well known, a conveying device typified by a belt conveyor supports a belt that conveys a conveyed object while rotating by many rotating bodies such as pulleys and rollers.

[0003] For these rotating bodies, for example, many pulleys and rollers are used in one conveyor, and they continue to rotate during the operation of the conveyor. If a problem occurs even in only one pulley or roller among many due to wear on the surface of the rotating body, etc., depending on the nature of the problem, the operation of the conveyor may become impossible, and the conveyor may stop or break.

[0004] Among the rotating bodies often used in belt conveyors, especially for the purpose of protecting the surface of a pulley, which is a rotating body that strongly contacts the belt, from wear and at the same time driving the conveyor effectively, or increasing the frictional resistance between the belt and a steel bare pulley, a lagging material may be wound around the pulley surface.

[0005] In the conventional method, as the lagging material, in many cases, for measures against surface wear and adhesion prevention, a method of baking or attaching a rubber-made or ceramic material is used according to known techniques and specifications.

[0006] However, generally, the causes of wear include the operating time of the conveyor, the properties of the conveyed object, and the material of the lagging material. Due to the material of the lagging material used, the installation position of the rotating body, and its environment, etc., although there are individual differences, there are naturally wear and damage, and the degree is different. Also, abnormal wear and peeling are phenomena that can also occur due to the belt skewing (snaking).

[0007] Therefore, rollers and pulleys for belt conveyors have been proposed in which a baked rubber outer coating with low hardness, wear resistance, and high rebound modulus is provided on the outer surface of the roller or pulley for supporting the belt in the belt conveyor (see, for example, Patent Document 1).

[0008] According to the above-mentioned Patent Document 1, a rubber outer layer with abrasive hardness, wear resistance, and high rebound elasticity is baked onto the outer circumference of the roller or pulley. As a result, the initial adhesion layer is less likely to form on the surface of the roller or pulley, and even if it does adhere, the residue will crack and peel off from the surface of the adhered material due to vibrations associated with the rotation of the roller or pulley, thus reducing the likelihood of belt meandering.

[0009] However, even if the severity of accidents decreases, unless some method for detecting and warning about roller wear is provided, it will not be possible to completely prevent the above-mentioned accidents in advance. Therefore, various methods have been proposed for detecting the degree of wear of rotating parts such as rollers.

[0010] It is well known that lagging material applied to the surface of many pulleys can experience uneven wear and peeling not only due to belt meandering but also due to residue adhering to the belt, which can have a significant impact on the operation and management of the entire conveyor, especially in the case of pulleys.

[0011] Whether the belt conveyor is running or stopped, inspecting individual pulleys while the belt is wrapped around them is not easy, and is practically impossible.

[0012] Therefore, there was a need for a method to detect in advance whether or not the lagging material applied to the surface of a rotating body was worn, even when the belt conveyor was in operation or when the belt was wrapped around the rotating body.

[0013] Furthermore, the applicant proposed a known technique using lagging material to diagnose the degree of surface wear, which involves providing a recess on the outer surface of a roller and filling this recess with a filler material that diagnoses the degree of wear of the pipe (see Patent Document 2).

[0014] Furthermore, as an alternative to using lagging material, even with bare pulleys, if a cage-type pulley is used, residue adhering to the conveyor belt will enter the cage-like gaps of the pulley and fall off without adhering to the pulley, thus preventing abnormal roller wear and belt breakage accidents (see, for example, Patent Document 3). [Prior art documents] [Patent Documents]

[0015] [Patent Document 1] Utility Model Registration No. 3211252 Gazette [Patent Document 2] Utility Model Registration No. 3190773 Gazette [Patent Document 3] Utility Model Registration No. 3191238 Gazette [Overview of the project] [Problems that the invention aims to solve]

[0016] However, the diagnostic detection method described in Patent Document 2 has the drawback of not being easily performed during operation or in an installed state. This is because the recessed portion of the filler material provided on the outer surface of the pipe is constantly rotating at high speed along with the pipe, making detection impossible.

[0017] Furthermore, continuing to operate a machine when dangerous conditions such as abnormal wear or peeling occur in the lagging material on the surface of the rotating pulley is obviously unsafe and unsecured, making early detection and treatment absolutely essential.

[0018] Furthermore, directly visually inspecting the rotating body or the lagging material wrapped around it for abnormal wear is extremely dangerous. Therefore, there was a need for a method to indirectly detect damage (detachment) to the rotating body or lagging material and safely notify the outside.

[0019] However, in order to safely notify the outside world of the failure of the lagging material, it is necessary to use sensors that detect wear and signals that warn personnel, mainly using electrical and electronic circuits. However, the objects in question are rotating bodies such as rollers and pulleys that are constantly rotating, so it was necessary to supply power from a power source on the non-rotating side (stationary side) and to receive signals from sensors on the rotating side, requiring electrical signal conductors to be connected between the stationary side and the wiring side.

[0020] Therefore, while it is conceivable to use a known rechargeable battery as the power source for the rotating part, there are issues such as the need for periodic charging, and even if conventional rechargeable batteries are adopted, there are many problems such as explosions due to ignition, as has been a recent concern. This limits the range of use, and could potentially hinder commercialization, making it difficult to determine if it would actually work.

[0021] Furthermore, it is conceivable to use brushes as a means of electrical conductivity between the stationary and rotating parts. However, brushes also wear down, requiring periodic inspection of the electrical conductivity of the wiring. In addition, the design and wiring must take into account the avoidance of damage or breakage of the wiring due to contact vibrations from brushes, etc., and the induction of dust explosions due to spark generation.

[0022] This invention aims to solve the above-mentioned problems and provide a rotating body abnormality detection device that can accurately detect and transmit abnormalities in rotating bodies such as rollers and pulleys. [Means for solving the problem]

[0023] In order to solve the above problems, the present invention is to minimize extraordinary situations by using electromagnetic induction to supply power and transmit and receive information between the fixed side and the rotating body (moving body) side for extraordinary phenomena such as excessive wear that occurs on the surface of rotating bodies such as pulleys and rollers.

[0024] That is, the invention according to claim 1 is a rotating body of a roller or pulley that guides the running of a belt. A lagging material is provided on the entire outer periphery of the rotating body, and a detection code connected by wiring is embedded in the lagging material. A first circuit is configured with a rotating body side coil that conducts to the detection code. A second circuit is configured with a fixed side coil provided on the fixed side and connected to a power source capable of supplying power to the rotating body side coil by electromagnetic induction. When the detection code is open or shorted, the first circuit sends a detection signal to the first circuit, and the second circuit receives the detection signal from the first circuit by electromagnetic induction to detect the disconnection of the detection code. It is an abnormal detection device for the surface of a rotating body characterized by this.

Effect of the Invention

[0025] As described above, according to the abnormal detection device for the rotating body of this invention, even when the belt conveyor is in operation, that is, even when the belt is wound around the rotating body and the rotating body is rotating, it is possible to detect the presence or absence of the exposure of the detection code due to the wear of the lagging material processed on the surface of the rotating body or the cutting (interruption) of the detection code due to abnormal pressing by the belt tension.

[0026] Also, it is very dangerous to directly visually confirm the presence or absence of abnormal wear of the rotating body main body or the lagging material installed on the main body, but by indirectly detecting the damage (peeling) of the rotating body main body or the lagging material and safely notifying the outside, it is possible to safely detect the abnormality of the rotating body.

[0027] Furthermore, since the conduction means for power and information communication between the rotating body side and the fixed side is non-contact, there is no worry about wear of conducting wires and conducting members accompanying the rotation of the rotating body or the generation of sparks, and maintenance is also easy.

Brief Description of the Drawings

[0028] [Figure 1] The following diagram shows the application of this invention to a belt conveyor pulley, with (A) being a front view and (B) being a side view. [Figure 2] This is a longitudinally enlarged side view showing the main part of the pulley described above. [Figure 3] This is an enlarged plan view of the same object. [Figure 4] This is a flowchart of the detection device of this invention. [Figure 5] Figures (A) through (D) are side views illustrating the sequence of belt severance accidents caused by ice chunks. [Modes for carrying out the invention]

[0029] Embodiments of this invention will be described based on the accompanying drawings. As is well known, the pulleys P, which are rotating bodies arranged on the head and tail sides of the belt conveyor A of this invention shown in Figures 1 to 3, consist of end plates 2 that close both ends of the pipe 1 and rotate together with the pipe 1, and a bearing shaft 3 that passes through the center of the end plates 2 and rotates together with the pipe 1.

[0030] As shown in Figure 2, the belt conveyor A consists of an endless belt a stretched between the aforementioned pulleys P, and the carrier side and return side are well-known and therefore omitted from the illustration, but the belt a is supported by carrier rollers and return rollers.

[0031] Furthermore, lagging material 5 is provided on the entire outer surface of pipe 1. Common lagging materials include rubber, ceramic, or synthetic resin paints used to protect the pipe surface from wear and rust. However, in this embodiment, lagging material 5 refers to the material applied to the pulley.

[0032] Furthermore, as for the material of the lagging material 5, W helical rubber lagging is generally often used in order to increase the coefficient of friction for driving and to remove residue and rainwater trapped between the pulley and the belt.

[0033] In this invention, the lagging material 5 is shown as a W-helical rubber lagging, which serves the above purpose, because a certain thickness of lagging material 5 is necessary to embed the detection code 8. However, the invention is not limited to this structure.

[0034] The surface of this lagging material 5 is provided with W-helical grooves 6, which serve not only to remove residue and rainwater, but also, for example, as shown in Figure 2, to hold the wiring 7 and detection code 8 embedded deep in the bottom of the grooves 6, although they may be located in the middle of the grooves 6.

[0035] In short, the material of the lagging material 5 should be such that it protects the pipe 1 from normal wear while simultaneously protecting it from residue adhering to belt a and sudden wear caused by belt meandering for a certain period of time.

[0036] Furthermore, while the lagging material 5 protects the pipe 1 from wear, if the surface of the lagging material 5 experiences abnormal wear, it is sufficient for the detection code 8 to be exposed, thereby detecting that a fracture has occurred.

[0037] The purpose of embedding this detection code 8 is to prevent rapid wear caused by residue adhering to belt a or by belt a meandering for a certain period of time.

[0038] The grooves and width of the rubber lagging material 5 processed on the surface of pulley P are determined by the surface pressure against external pressure such as the tension of belt a, and in many cases, there are standardized specifications. However, it is possible to address this using known technologies without adhering to the specifications.

[0039] Furthermore, the exchange of power and signals (such as signals indicating the cutting of the detection code) from the rotating body to the stationary body employs an electromagnetic induction method, and the alarm system is activated when the cutting of the detection code 8 embedded in the lagging material 5 is detected.

[0040] The configuration consists of multiple coils 9 provided along the circumference of the front side of the end plate 2 on the pulley P (rotating body) side, and a coil 10 fixed to the frame 11 (fixed side) that faces one of the coils 9 on the pulley P side with a minimum necessary gap d between them. Power and signals are exchanged between these coils 9 and coil 10 by electromagnetic induction.

[0041] During normal operation, an AC current voltage from a power source (not shown) is supplied to a coil 10 fixed to the frame 11 on the stationary side that is not rotating. An AC magnetic field (AC power) is generated in the coil 9 on the rotating pulley P side opposite to the coil 10 due to electromagnetic induction. This power flows through the detection cord 8 and wiring 7 connected in series with the coil 9. The current and voltage flowing through the rotating coil 9 are measured when these detection cords 8, etc. are conducting without breaks, and if they are within the appropriate range, it is determined that there is no break.

[0042] If the detection cord 8 embedded in the lagging material 5 is severed due to surface wear of the pulley P, the circuit connected to the coil 9 will lose conductivity. As a result, a detection signal indicating the break is sent to the circuit of the coil 9, and this detection signal is transmitted to the coil 10, which supplies power via electromagnetic induction. If the current and voltage on the fixed side become such that it is determined to be a break in the coil 9, then it is determined that the detection cord 8 is broken.

[0043] If a disconnection in detection code 8 is detected, for example, an alarm patrol light (registered trademark) will immediately illuminate at the site, and at the same time, a notification signal can be sent to the operational control center.

[0044] Referring to the flowchart in Attached Figure 4, the general flow of resolving problems using the electromagnetic induction method rotating body abnormality detection device of this invention will be explained.

[0045] First, let's consider a scenario where the lagging material 5 on the surface of the drive pulley P experiences abnormal wear. We will explain how, if wear exceeding a specified amount is considered abnormal wear, the detection code 8 embedded in the lagging material 5 is cut, and the alarm system is activated.

[0046] 1) The lagging material 8 on the surface of the pulley P (rotating body) wears abnormally, and the detection code 8 embedded inside is cut. 2) As a result of the detection code 8 being cut, the electrical current is interrupted between the coil 9 on the rotating side, i.e., the first circuit X side (pulley P side), and the coil 10 on the stationary side, i.e., the second circuit Y side. 3) Upon detecting that the power supply has been interrupted, the IT board within the first circuit X detects that it has been shut off and emits a detection signal. This signal is received by the IT board on the fixed second circuit Y side via electromagnetic induction, and a determination device in the control panel confirms that the first circuit X side has been shut off and determines that the lagging material 5 has been abnormally worn. 4) When this happens, the signal from the detector causes the patrol light (registered trademark) on the machine's control panel to flash (or light up), notifying external maintenance personnel, and simultaneously activating an emergency information alarm system at the control center. 5) After the alarm system has issued an alarm, detection work on the rotating body is no longer necessary, so in some cases a command to cut off the power supply to the first circuit is issued, stopping the power supply from the power source.

[0047] Next, we will explain other specific examples, accidents, and countermeasures based on Figures 4 and 5. In 2010, at an indoor coal storage facility of a major thermal power plant, a block of ice that had frozen solid during the winter became entangled in a bare tail pulley (a steel pipe without lagging material covering its surface) of a BW1600 conveyor, eventually severing the steel cord belt. The accident occurred in an outdoor facility during winter, involving a large conveyor with a belt width of 1600mm and using a steel cord belt.

[0048] Figure 5(A) shows the normal operation near the tail pulley P. A snow removal cleaner 12 is provided near the surface of the tail pulley P opposite to the surface that contacts the return belt a.

[0049] For days, parts of the equipment froze over, eventually forming ice blocks C that fell onto the conveyor system. Some of these ice blocks hit the frame and were carried on the return belt a to the tail pulley P. The equipment manager, knowing this was an annual occurrence, assumed that the permanently installed sheet metal snow shovel cleaner 12 located just before the tail pulley P would remove the ice (Figure 5(B)).

[0050] However, in this case, the ice mass C could not be removed and grew while trapped between the bare tail pulley P and the steel return belt a (see Figure 5(C)). It then wrapped around the pulley P and was further compressed by the belt tension, becoming a solid mass, at which point it was cut from belt a (see Figure 5(D)).

[0051] From this, we can imagine that if rubber lagging material had been attached to the surface of a steel pipe pulley (bare pulley) that did not have lagging material attached to its surface, the elasticity of the rubber would have deformed the ice block and prevented the breakage accident.

[0052] Alternatively, even with a bare pulley, if a known cage-type pulley (see, for example, Patent Document 3) with a cage-like pulley design had been used, it is likely that the ice chunk would have entered the cage-like gaps before it grew too large, thus preventing a belt break. However, even if a break had not occurred, it is highly probable that it would have taken a considerable amount of time for the information to reach the equipment's control center.

[0053] Based on the lessons learned from the above case, this invention can be applied not only to the detection of abnormal wear of lagging material, but also, as an example of an application, to an early detection system for accidents in coal storage facilities of outdoor equipment under harsh winter conditions.

[0054] This system involves laying rubber lagging material with embedded wires on the pulley surface. This allows for an alarm to be triggered when a thin, embedded detection cord 8 is cut, before the ice block continues to grow without breaking and pushes against the belt's core (steel cord), potentially damaging the entire belt.

[0055] In the past, there have been many outdoor conveyor systems, not just coal storage facilities like this one, so this system will be effective in ensuring safe and secure operations.

[0056] If the wire embedded in the lagging material is severed, the alarm patrol light (registered trademark) will immediately illuminate, and a notification signal will be sent to the control center operating the system.

[0057] 1) Assuming that the lagging material on the pulley surface is not adhered, it is a prerequisite that the detection code 8 be embedded in the rubber lagging material 5 on the pulley surface. 2) In order to make it relatively easy to cut the detection cord 8 embedded in the lagging material 5, it is conceivable to embed the wire by inserting it into lagging material 5 with a hardness slightly lower than that of the belt (for example, the lagging material of known Patent Document 1) or by overlapping and wrapping thin lagging material. 3) By using this lagging material 5, it is also expected that residues and ice chunks will be prevented from adhering to the pulley surface. 4) When a certain amount of pressure is applied to the lagging material 5, the embedded detection code 8 is cut (damaged), and the alarm system on the second circuit Y side is activated by the remote system, and at the same time, a notification is sent to the control center.

[0058] The embodiments of the rotating body abnormality detection device of this invention have been described above. However, the scope of application of this invention is not limited to drive and driven pulleys, but can also be applied to belt support rollers. Furthermore, since there are many outdoor conveyor systems, not just coal storage facilities, applying this invention to them will enable safe and secure operation.

[0059] Furthermore, it can be applied to various rotating bodies as an anomaly detection device that requires a sensor on the rotating body side, with one on the stationary side and the other on the rotating side. [Explanation of Symbols]

[0060] A belt conveyor P Pulley a belt X 1st circuit Y 2nd circuit 1 pipe 2 end plate 3 Bearing shaft 5 Lagging material 6 grooves 7 Wiring 8 Detection Codes 9. Coil (rotating body side) 10 coils (fixed side) 11 frames 12 Snow shovel cleaner

Claims

[Claim 1] An abnormality detection device for the surface of a rotating body, comprising a rotating body such as a roller or pulley that guides the movement of a belt, wherein a lagging material is provided on the entire outer circumference of the rotating body, detection cords connected to the lagging material by wiring are embedded in the lagging material, and a rotating body-side coil that conducts to the detection cords is provided to constitute a first circuit, and a fixed-side coil is provided on the fixed side that is connected to a power source capable of supplying power to the rotating body-side coil by electromagnetic induction, wherein when the conductivity of the detection cord is interrupted, the first circuit sends a detection signal to the first circuit, and the second circuit receives the detection signal from the first circuit by electromagnetic induction and detects the disconnection of the detection cord.

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