Method and system for predicting belt life

Abstract

To provide a method having determination reference for predicting the life of a belt and the determination reference based on temperature change of the belt.SOLUTION: A friction transmission belt includes rubber and repeats a cycle with a section from a drive start to a drive end as one cycle. A method measures a temperature of the belt during driving, stores measured temperature when a prescribed time passes from a time point of reaching a preset temperature at which a measurement temperature of the belt is determined for each cycle, evaluating stored measured temperatures with time, and predicts the life of the belt with the indication of a maximum point of the stored measured temperature as determination reference.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method and system for predicting the life of a belt, and more particularly to a method and system for predicting the life of a friction power transmission belt. [Background technology]

[0002] A friction transmission belt made of rubber deteriorates with continued use due to hardening of the rubber. In addition, the friction transmission belt is constantly under tension when wrapped around the pulleys, and is repeatedly subjected to bending loads from each pulley during operation, which can cause the belt to deteriorate. A friction transmission belt that has deteriorated and has a reduced power transmission efficiency is determined to have reached the end of its life soon, and is replaced with a new one.

[0003] In view of the above circumstances, Patent Document 1 proposes observing the change in the internal temperature of a transmission belt in order to predict the life of the transmission belt. Patent Document 1 also shows that the internal temperature of a transmission belt increases over time during driving (see FIG. 16 of Patent Document 1, etc.). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-118297 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, Patent Document 1 shows the observation results of the temperature of the belt during driving, but does not fully consider how to predict the life of the belt based on these observation results.

[0006] In view of the above, an object of the present invention is to provide a method for predicting the life of a belt, the method comprising a criterion based on a temperature change of the belt, and a system for easily predicting the life of the belt based on the method. [Means for solving the problem]

[0007] A method for predicting the life of a belt according to one aspect of the present invention includes the steps of: the belt is a friction drive belt that includes rubber and repeats one cycle from the start of driving to the end of driving, Measure the temperature of the belt while it is moving; storing the measured temperature of the belt at a predetermined time after the measured temperature of the belt reaches a set temperature for each cycle; Evaluating the stored measured temperatures over time; The life of the belt is predicted based on the criterion of whether the stored measured temperature shows a maximum point.

[0008] A method for predicting a life of a belt according to another aspect of the present invention includes the steps of: The belt is a friction drive belt that includes rubber and is continuously driven. Measure the temperature of the belt while it is moving; Evaluating the measured temperature of the belt over time; The life of the belt is predicted based on the criterion of whether the measured temperature of the belt shows a maximum point.

[0009] The amount of frictional heat generated between the friction transmission belt and the pulley increases as the rubber hardens (deteriorates) with continued use. Therefore, it is considered that the temperature of the belt, whose rubber has hardened to a certain extent, shows a tendency to rise due to heat generation caused by bending. If the hardening of the rubber progresses with further continued use, cracks will appear in the belt. And since the area with the crack that has spread with the loss of rubber includes a crack that does not generate heat due to bending, the generation of frictional heat is gradually suppressed due to the occurrence of such cracks, and as a result, the temperature of the belt changes from a tendency to rise to a tendency to fall. The present invention has been made based on this phenomenon, and has as a judgment criterion the fact that the measured temperature of the belt shows a maximum point.

[0010] A preferred embodiment of the present invention is The measured temperature is a temperature measured at any one of the inner circumferential surface, the outer circumferential surface, and the inside of the belt.

[0011] According to the inventors' research, it is found that the temperature of any of the above-mentioned locations of the friction transmission belt is likely to show a local maximum point due to the above-mentioned phenomenon. Therefore, according to this aspect, it is possible to more appropriately predict the life of the belt.

[0012] A system for predicting the life of a belt according to one aspect of the present invention includes: a friction transmission belt including rubber, which repeats one cycle from the start of driving to the end of driving; A measuring unit for measuring the temperature of the belt during driving; a memory unit that stores a measured temperature of the belt at a predetermined time after the measured temperature of the belt reaches a set temperature for each cycle; A calculation unit that evaluates the measured temperatures stored in the memory unit over time; a prediction unit that predicts a life of the belt based on the evaluation result of the calculation unit, The prediction unit predicts the life of the belt using as a criterion whether the measured temperature stored in the memory unit indicates a maximum point.

[0013] A system for predicting a life of a belt according to another aspect of the present invention includes: a friction transmission belt including rubber and continuously driven; A measuring unit for measuring the temperature of the belt during driving; a calculation unit for evaluating the measured temperature of the belt over time; a prediction unit that predicts a life of the belt based on the evaluation result of the calculation unit, The prediction unit predicts the life of the belt using as a criterion whether the measured temperature of the belt indicates a maximum point.

[0014] According to these aspects, by providing the calculation unit and the prediction unit, the life of the belt can be easily predicted. Effect of the Invention

[0015] As described above, according to the present invention, it is possible to provide a method for predicting the life of a belt, the judgment criterion being based on a temperature change of the belt, and a system that can easily predict the life of a belt based on the method. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram of a system according to an embodiment. [Diagram 2] 2 is a perspective view of a friction power transmission belt included in the system of FIG. 1. [Diagram 3] 4 is an approximation curve showing the change over time in the measured temperature at a predetermined location when the measured temperature of the friction transmission belt of the example was evaluated. [Figure 4] Photographs of the side of a friction transmission belt being evaluated in an example were taken 212 hours and 283 hours after the start of driving. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a method for predicting a belt life according to a first embodiment of the present invention will be described with reference to the drawings, by illustrating a system for realizing the method.

[0018] As shown in FIG. 1, the system 100 according to this embodiment includes a belt 1, a plurality of pulleys 2 around which the belt 1 is wound, a measurement unit 3 that measures the temperature of the belt 1, a memory unit 4 that stores temperature information of the belt 1 acquired by the measurement unit 3, a calculation unit 5 that evaluates the temperature of the belt 1 over time using the temperature information from the memory unit 4, and a prediction unit 6 that predicts the life of the belt 1 based on the evaluation result of the calculation unit 5.

[0019] As shown in FIG. 2, the belt 1 of this embodiment is an endless friction transmission belt used to transmit power between a plurality of pulleys 2, and more specifically, a cog V-belt. Thus, the belt 1 has a pair of side surfaces 11 that approach each other from the outer periphery toward the inner periphery (cog side). That is, the cross-sectional shape of the belt 1 along the width direction is an isosceles trapezoid whose width decreases from the outer periphery toward the inner periphery. Corresponding to the belt 1, as shown in FIG. 1, the pulley 2 has a V-shaped groove 21. That is, the pulley 2 is formed with the groove 21 for the belt 1 to bite into over its outer periphery. The groove 21 has a pair of opposing surfaces 211 that approach each other from the outer side toward the inner side in the radial direction of the pulley 2. The space inside the groove 21 (the space between the pair of opposing surfaces 211) has a shape in which the width decreases from the outer side toward the inner side in the radial direction of the pulley 2. When the belt 1 is disposed inside the groove 21 (when disposed in the space), the side surface 11 abuts (contacts) against the opposing surface 211 of the groove 21. When the belt 1 is driven in the system 100, friction occurs between the side surface 11 of the belt 1 and the opposing surface 211 of the pulley 2, which generates heat (frictional heat).

[0020] The belt 1 of the present embodiment may reach a high temperature of 80° C. or more in each cycle. Specifically, in each cycle, the temperature of the outer circumferential surface of the belt 1 may reach 80° C. or more, the temperature of the inner circumferential surface may reach 90° C. or more, and the temperature inside may reach 100° C. or more.

[0021] The belt 1 of this embodiment is incorporated in a transmission of an agricultural machine such as a tractor. This type of agricultural machine is used such that it is repeatedly driven and stopped. For example, this type of agricultural machine is put into a driven state when the agricultural work of the day starts, and is stopped when the agricultural work ends, and is driven in the same way on the next agricultural work day. Thus, the belt 1 of this embodiment is driven intermittently, with one cycle being from the start to the end of the agricultural machine's drive. Then, by plotting the temperature of a predetermined location of the belt 1 over time in each cycle, a curve showing the temperature of the belt 1 increasing over time due to the frictional heat can be obtained.

[0022] 2, the belt 1 of this embodiment has a plurality of inwardly protruding protrusions 12 (cogs) in order to enhance flexibility in the longitudinal direction. The plurality of protrusions 12 are formed at a constant pitch in the longitudinal direction of the belt 1. The belt 1 also has a plurality of grooves formed between adjacent protrusions 12.

[0023] The belt 1 includes a belt body 13 containing rubber, a lower cloth 14 covering the inner peripheral surface of the belt body 13, and an upper cloth 15 covering the outer peripheral surface of the belt body 13.

[0024] The belt body 13 has a first rubber layer 131 on the inner circumferential side, a second rubber layer 132 on the outer circumferential side, and a core layer 133 disposed between the first rubber layer 131 and the second rubber layer 132.

[0025] The inner circumferential surface of the first rubber layer 131 has an uneven shape for forming the multiple protrusions 12. As the rubber hardens, cracks tend to occur on this inner circumferential surface, particularly from the base ends of the protrusions 12 toward the core layer 133. The inner circumferential surface of the first rubber layer 131 is directly covered by the lower cloth 14.

[0026] On the other hand, the outer peripheral surface of the second rubber layer 132 has a flat shape. The outer peripheral surface of the second rubber layer 132 is directly covered by the upper cloth 15.

[0027] The first rubber layer 131 and the second rubber layer 132 are formed of a rubber composition. Examples of the rubber components of the rubber composition include natural rubber (NR), butadiene rubber (BR), styrene-butadiene rubber (SBR), ethylene-propylene rubber (EPR), ethylene-propylene-diene rubber (EPDM), isoprene rubber (IR), acrylonitrile-butadiene rubber (NBR), hydrogenated nitrile rubber (HNBR), isobutylene-isoprene rubber (IIR), chloroprene rubber (CR), chlorosulfonated polyethylene rubber (CSM), chlorinated butyl rubber (CIIR), brominated butyl rubber (BIIR), silicone rubber (SR), urethane rubber (UR), acrylic rubber (ACR), and fluororubber (FR). The rubber components may be used alone or in combination.

[0028] The rubber composition may contain additives other than the rubber component, such as fillers such as carbon black, silica, calcium carbonate, flame retardants such as ethylene bistetrabromophthalimide, crosslinking agents such as sulfur, organic peroxides, vulcanization accelerators such as zinc oxide, plasticizers such as dioctyl adipate, hardness regulators such as paraffin oil, antioxidants such as benzimidazole compounds, lubricants, etc.

[0029] The core layer 133 has an adhesive rubber 1331 that adheres the second rubber layer 132 to the first rubber layer 131, and a core wire 1332 embedded in the adhesive rubber 1331. The core wire 1332 may be a metal cord such as a steel cord, or may be made of synthetic fibers such as polyester fiber, polyamide fiber, or aramid fiber, carbon fiber, or glass fiber. The core layer 133 may have canvas instead of the core wire 1332.

[0030] The lower cloth 14 covers only the inner peripheral surface of the first rubber layer 131. That is, the side surface of the first rubber layer 131 is exposed and forms a part of the side surface 11 of the belt 1. The upper cloth 15 covers only the outer peripheral surface of the second rubber layer 132. That is, the side surface of the second rubber layer 132 is exposed and forms a part of the side surface 11 of the belt 1. In addition, the side surface of the core layer 133 is also exposed and forms a part of the side surface 11 of the belt 1. In this way, the side surface 11 of the belt 1 is composed of the exposed side surfaces of the first rubber layer 131, the second rubber layer 132, and the core layer 133 including the adhesive rubber 1331. In short, the belt 1 has an exposed rubber side surface 11 that is not covered by other members such as a cloth member.

[0031] The lower cloth 14 and the upper cloth 15 are made of cloth material such as woven cloth, knitted cloth, nonwoven cloth, etc., made of threads such as cotton, polyamide fiber, polyester fiber, aramid fiber, etc.

[0032] The measurement unit 3 of this embodiment is configured to measure the temperature over time at a predetermined location of the belt 1. The measurement unit 3 may be configured to measure the temperature of the belt 1 over time at intervals of 30 minutes or less, preferably 15 minutes or less, more preferably 10 minutes or less, even more preferably 5 minutes or less, and even more preferably 1 minute or less, and may be further configured to measure the temperature of the belt 1 at intervals as small as possible.

[0033] As shown in FIG. 1, the system 100 of this embodiment includes a first measuring unit provided in an RFID tag T embedded in the belt 1 as a measuring unit 3 for measuring the temperature inside the belt 1, and an RFID reader R as a reading unit for communicating with the RFID tag T and reading information (temperature information) of the RFID tag T. The RFID tag T is embedded in the second rubber layer 132 of the belt 1. The RFID reader R is disposed at a position where it can transmit an electromagnetic wave toward the outer peripheral surface of the belt 1 and receive the electromagnetic wave returned from the RFID tag T. The RFID tag T may be embedded in the first rubber layer 131 of the belt 1. In this case, it is preferable that the RFID reader R is disposed at a position where it can transmit an electromagnetic wave toward the inner peripheral surface of the belt 1 and receive the electromagnetic wave returned from the RFID tag T.

[0034] The RFID tag T includes an IC chip and an antenna connected to the IC chip. The IC chip is mounted in the center of a rectangular base sheet. The antenna extends toward both ends of the base sheet in the longitudinal direction. The antenna is configured to generate a current due to electromagnetic waves from an RFID reader R. The IC chip is configured to be driven by the current generated in the antenna. In other words, the RFID tag T is a passive type.

[0035] The IC chip is an IC chip with an integrated temperature sensor. That is, the IC chip includes the first measurement unit. The IC chip includes a temperature sensor that detects the temperature of the belt 1, a control circuit that controls the driving of the temperature sensor, and a memory that stores temperature information of the belt 1. The temperature sensor and the control circuit are electrically connected by wiring. In addition, the wiring is adhered to the temperature sensor and the control circuit by a conductive adhesive.

[0036] The temperature sensor is composed of a thermistor whose resistance value changes with temperature change. The thermistor may be an NTC thermistor or a CTR thermistor whose resistance value decreases with increasing temperature. The thermistor may be a PTC thermistor whose resistance value increases with increasing temperature. The temperature sensor is configured to output a voltage or current according to the change in the resistance value of the thermistor. The IC chip is configured to convert the value of the voltage or current output by the temperature sensor into a temperature value by the control circuit. The temperature sensor may be composed of a thermocouple. The thermocouple is a pair of two metal wires having different components connected to each other, and outputs a thermoelectromotive force according to a temperature change at the connection point of these metal wires.

[0037] The RFID tag T is configured to receive electromagnetic waves from the RFID reader R and transmit the temperature information stored in the memory to the RFID reader R. The RFID reader R is configured to transmit the temperature information received from the IC chip to the storage unit 4.

[0038] Furthermore, the system 100 of this embodiment includes, as the measurement unit 3, a second measurement unit (not shown) that measures the temperature of the inner circumferential surface or the outer circumferential surface of the belt 1. As the second measurement unit, a radiation temperature sensor that measures the temperature by irradiating the inner circumferential surface or the outer circumferential surface of the belt 1 with infrared rays or the like can be used.

[0039] Each of the first measuring unit and the second measuring unit is configured to be able to measure a temperature in the range of -20°C to 150°C.

[0040] The memory unit 4 of this embodiment is configured to store at least the measured temperature when a predetermined time has elapsed since the temperature of the belt 1 reached a predetermined set temperature for each cycle. The memory unit 4 of this embodiment is configured to store the temperature of the belt 1 over time at least from the time when the set temperature is reached. For example, the memory unit 4 may store the temperature of the belt 1 over time at intervals of 30 minutes or less, preferably 15 minutes or less, more preferably 10 minutes or less, even more preferably 5 minutes or less, and even more preferably 1 minute or less from the time when the set temperature is reached, and may further store the temperature of the belt 1 at intervals as small as possible. That is, the memory unit 4 may store the temperature of the belt 1 at the above-mentioned intervals at least from the time when the set temperature is reached for each cycle.

[0041] When storing the measured temperatures of each cycle in the memory unit 4, the system 100 may provide the temperatures of the belt 1 over time stored in the above-mentioned intervals to the calculation unit 5, and cause the calculation unit 5 to create an approximation curve showing the temperature changes over time. The system 100 may then store the recursive measured temperatures determined based on the approximation curve in the memory unit 4. This makes it possible to extract the measured temperatures more appropriately.

[0042] The set temperature is preferably higher than the air temperature of the environment in which the agricultural machine is used, for example, 40° C. or higher, and preferably 50° C. or higher. The specified time may be set to include a temperature range in which the temperature rise is considered to have plateaued, for example, a temperature range in which the temperature rise rate per minute is less than 1° C., preferably 0.5° C. or lower. Alternatively, the specified time may be set so that the number of samples of the measured temperature is as large as possible and includes a temperature range in which the temperature of the belt 1 is considered to be rising stably (rising linearly with time), for example, a temperature range in which the temperature rise rate per minute is 1° C. or higher, preferably 2° C. or higher.

[0043] The calculation unit 5 of this embodiment creates an approximation curve showing the time-dependent change of the measured temperatures (measured temperatures extracted from each cycle) consisting of up to n items on a coordinate system having a time axis and a temperature axis. Furthermore, when a cycle is added and the measured temperature is added, the calculation unit 5 is configured to update the approximation curve based on the additional measured temperatures.

[0044] As the rubber contained in the belt body 13 hardens, cracks will occur. Before cracks occur when the rubber hardens to a certain extent, the amount of frictional heat generated between the belt 1 and the pulley 2 increases as the belt body 13 hardens. Therefore, before cracks occur when the rubber has deteriorated (hardened) to a certain extent, the measured temperature is considered to show an upward trend due to heat generation due to bending. As the rubber hardens further with continued use, cracks will occur in the belt body 13. And since the area with the crack that has spread with the loss of rubber is an area that includes a crack that does not generate heat due to bending, the generation of frictional heat will be gradually suppressed by the occurrence of such cracks. As a result, the temperature of the belt 1 will change from an upward trend to a downward trend.

[0045] Therefore, the approximation curve created by the calculation unit 5 has an increase part of the measured temperature before the crack occurs and a decrease part of the measured temperature after the crack occurs, and can show a maximum point which is a boundary between the increase part and the decrease part. The approximation curve can also show a straight line part where the temperature change is ±1°C or less in a time region before the increase part and in a time region ranging from 10 cycles to 100 cycles. Since the temperature change of the belt 1 due to the frictional heat can be affected by a change in air temperature, a simple curve may cause drift, which may affect the understanding of the maximum point. In contrast, the approximation curve makes it easier to understand the increasing and decreasing trends of the belt temperature, that is, makes it easier to understand the maximum point.

[0046] The approximation curve based on the measured temperatures of the outer circumferential surface and the inner circumferential surface of the belt 1 may continue to show the decreasing portion after the maximum point, while the approximation curve based on the measured temperatures inside the belt 1 may show the decreasing portion and then show an increasing portion again.

[0047] When the prediction unit 6 determines that the slope of the rising portion shows a decreasing tendency over time, it may infer that the curve will reach the maximum point in the future and determine that the belt 1 has reached the end of its life at this point. This determination can greatly increase the possibility of preventing an accident caused by damage to the belt 1.

[0048] In addition, the prediction unit 6 may determine that the belt 1 has reached the end of its life after grasping that the approximation curve has reached the maximum point. This determination can extend the use time of the belt 1 as much as possible. In detail, when the belt 1 is a cogged V-belt as in the present embodiment, the cracks often occur at the base end of the protrusion 12 and gradually extend toward the core 1332. It is considered that the performance of the belt 1 in which the cracks have not reached the core 1332 has not deteriorated so much that it does not pose a problem in practical use. In other words, determining that the belt 1 in which the cracks have not reached the core 1332 has reached the end of its life and replacing it leads to the wasteful disposal of the belt 1 in a usable state.

[0049] Furthermore, the prediction unit 6 may determine that the belt 1 has reached the end of its life when it is ascertained that the approximation curve based on the measured temperature inside the belt 1 shows an upward portion again. According to this determination, the usage time of the belt 1 can be further extended.

[0050] Next, a method for predicting the life of a belt according to a second embodiment of the present invention will be described. Note that components having the same functions as those in the first embodiment will be given the same reference numerals and the description thereof will be omitted.

[0051] The belt 1 of the second embodiment is incorporated in an air conditioning system of a factory or the like. An example of such a belt 1 is a fan belt. Some of such belts are continuously driven without being stopped once they are driven. The time for which they are continuously driven is, for example, 24 hours or more. That is, the belt 1 of this embodiment is driven continuously and non-intermittently for 24 hours or more. The time for which they are continuously driven may be 50 hours or more, 100 hours or more, 150 hours or more, 200 hours or more, 250 hours or more, or 300 hours or more.

[0052] The belt 1 of the present embodiment may reach a high temperature of 80° C. or more during continuous driving. Specifically, in each cycle, the temperature of the outer circumferential surface of the belt 1 may reach 80° C. or more, the temperature of the inner circumferential surface may reach 90° C. or more, and the temperature inside may reach 100° C. or more.

[0053] The system of this embodiment includes a belt 1, a plurality of pulleys 2 around which the belt 1 is wound, a measurement unit 3 that measures the temperature of the belt 1, a calculation unit 5 that evaluates the temperature of the belt 1 over time using temperature information of the belt 1 acquired by the measurement unit 3, and a prediction unit 6 that predicts the life of the belt 1 based on the evaluation result of the calculation unit 5.

[0054] The measurement unit 3 of this embodiment is configured to measure the temperature over time at a predetermined location of the belt 1. The measurement unit 3 may be configured to measure the temperature of the belt 1 over time at intervals of 30 minutes or less, preferably 15 minutes or less, more preferably 10 minutes or less, even more preferably 5 minutes or less, and even more preferably 1 minute or less, and may be further configured to measure the temperature of the belt 1 at intervals as small as possible.

[0055] The calculation unit 5 of this embodiment is configured to create an approximation curve showing the temperature change over time of the belt 1 measured by the measurement unit 3 at the above-mentioned intervals on a coordinate system having a time axis and a temperature axis. The calculation unit 5 of this embodiment is also configured to sequentially update the approximation curve based on the temperature information continuously transmitted from the measurement unit 3.

[0056] Based on the same theory as in the first embodiment, the approximation curve created by the calculation unit 5 in the second embodiment has a portion where the temperature of the belt 1 increases before a crack occurs and a portion where the temperature of the belt 1 decreases after a crack occurs, and can show a maximum point that is a boundary between the increase portion and the decrease portion. The approximation curve can also show a linear portion where the temperature change is within ±1°C in a time region before the increase portion and in a time region ranging from 50 hours to 200 hours after the start of driving.

[0057] The approximation curve based on the measured temperatures of the outer circumferential surface and the inner circumferential surface of the belt 1 may continue to show the decreasing portion after the maximum point, while the approximation curve based on the measured temperature inside the belt 1 may show the decreasing portion and then show an increasing portion again.

[0058] When the prediction unit 6 of this embodiment grasps that the slope of the rising portion shows a decreasing tendency over time, it may infer that the curve will show the maximum point in the future and determine that the belt 1 has reached the end of its life at this point. The prediction unit 6 may also determine that the belt 1 has reached the end of its life after grasping that the curve has shown the maximum point. Furthermore, the prediction unit 6 may determine that the belt 1 has reached the end of its life when it grasps that the approximation curve based on the measured temperatures inside the belt 1 shows another rising portion.

[0059] As described above, one embodiment has been shown as an example, but the method and system for predicting the life of a belt according to the present invention are not limited to the configuration of the above embodiment. Furthermore, the method and system for predicting the life of a belt according to the present invention are not limited to the above-mentioned effects. The method and system for predicting the life of a belt according to the present invention can be modified in various ways without departing from the gist of the present invention.

[0060] For example, in the first embodiment, a cogged V-belt is exemplified, but the belt of the present invention is not limited to this and may be, for example, a double cogged belt having cogs on the outer peripheral surface, or a V-belt having no cogs on either the inner or outer peripheral surface.

[0061] Furthermore, the method and system of the present invention are not limited to the applications described in the above embodiments, and can be used in vehicles other than agricultural machinery.

[0062] The present disclosure includes the following: (1) 1. A method for predicting belt life, comprising: the belt is a friction drive belt that includes rubber and repeats one cycle from the start of driving to the end of driving, Measure the temperature of the belt while it is moving; storing the measured temperature of the belt at a predetermined time after the measured temperature of the belt reaches a set temperature for each cycle; Evaluating the stored measured temperatures over time; The method further comprises predicting the life of the belt using the stored measured temperature showing a maximum point as a criterion for judgment. (2) 1. A method for predicting belt life, comprising: The belt is a friction drive belt that includes rubber and is continuously driven. Measure the temperature of the belt while it is moving; Evaluating the measured temperature of the belt over time; The method of predicting the life of the belt using a criterion that the measured temperature of the belt exhibits a maximum point. (3) The method according to (1) or (2) above, wherein the measured temperature is a temperature measured at any one of an inner circumferential surface, an outer circumferential surface, and an interior of the belt. (4) A system for predicting belt life, comprising: a friction transmission belt including rubber, which repeats one cycle from the start of driving to the end of driving; A measuring unit for measuring the temperature of the belt during driving; a memory unit that stores a measured temperature of the belt at a predetermined time after the measured temperature of the belt reaches a set temperature for each cycle; A calculation unit that evaluates the measured temperatures stored in the memory unit over time; a prediction unit that predicts a life of the belt based on the evaluation result of the calculation unit, The prediction unit predicts the life of the belt using as a criterion whether the measured temperature stored in the memory unit indicates a maximum point. (5) A system for predicting belt life, comprising: a friction transmission belt including rubber and continuously driven; A measuring unit for measuring the temperature of the belt during driving; a calculation unit for evaluating the measured temperature of the belt over time; a prediction unit that predicts a life of the belt based on the evaluation result of the calculation unit, The prediction unit predicts the life of the belt based on a criterion that the measured temperature of the belt indicates a maximum point. (6) The system according to (4) or (5) above, wherein the measurement unit measures the temperature of one of the inner surface, the outer surface, or the inside of the belt. (7) An RFID tag is embedded in the belt, The system according to any one of (4) to (6) above, wherein the RFID tag has the measurement unit for measuring the temperature inside the belt. EXAMPLES

[0063] The present invention will now be described more specifically with reference to examples.

[0064] A cogged V-belt was produced with an RFID tag with a temperature sensor embedded in the outer surface (second rubber layer) of the belt body. This belt was attached to a biaxial running test machine equipped with two pulleys and was continuously driven at a belt speed of 15 m / s under load in a room temperature environment. The internal temperature of the belt was measured over time using the temperature sensor in the RFID tag, and the temperatures of the outer surface, inner surface, and side of the belt were measured over time using an infrared temperature sensor.

[0065] As shown in Figure 3, the approximation curves showing the temperature changes on the outer circumferential surface, inner circumferential surface, and inside of the cogged V-belt showed a linear portion, followed by an increasing portion, then a decreasing portion, with a maximum point at the boundary between the increasing portion and the decreasing portion. On the other hand, the approximation curve showing the temperature changes on the side generally showed a decreasing trend.

[0066] As shown in Figure 4, no cracks were observed in the appearance of the belt side 212 hours after the start of operation. Referring to the approximation curves in Figure 3, it was found that in the time range around 212 hours after the start of operation, the approximation curves for the outer circumferential surface, inner circumferential surface, and interior of the belt showed upward sections. From these results, it is believed that in the time range around 212 hours, although the rubber had hardened to a certain extent, it was not to the point where cracks would appear in the belt, and the upward sections of the approximation curves were due to frictional heat generated between the belt and the pulley.

[0067] On the other hand, as shown in Figure 4, when the appearance of the belt side was observed 283 hours after the start of driving, the occurrence of cracks that reached the core wire was observed. Referring to the approximation curves in Figure 3, it was observed that the approximation curve of the outer peripheral surface of the belt showed a maximum point about 40 hours after 283 hours. Also, it was observed that the approximation curve of the inner peripheral surface of the belt showed a maximum point about 50 hours after 283 hours. Also, it was observed that the approximation curve of the inside of the belt showed a maximum point about 20 hours after 283 hours. These results are considered to be due to the occurrence of cracks that reached the core wire gradually suppressing the generation of frictional heat and causing the temperature of the belt to change from an increasing trend to a decreasing trend. On the other hand, no maximum point was observed in the approximation curve of the side of the belt. [Explanation of symbols]

[0068] 1: belt, 11: side, 12: protrusion, 13: belt body, 131: first rubber layer, 132: second rubber layer, 133: core layer, 1331: adhesive rubber, 1332: core wire, 14: lower cloth, 15: upper cloth, 2: pulley, 21: groove, 211: opposing surface, 3: measuring unit, 4: memory unit, 5: calculation unit, 6: prediction unit, 100: system, T: RFID tag, R: RFID reader

Claims

1. 1. A method for predicting belt life, comprising: the belt is a friction drive belt that includes rubber and repeats one cycle from the start of driving to the end of driving, Measure the temperature of the belt while it is moving; storing the measured temperature of the belt at a predetermined time after the measured temperature of the belt reaches a set temperature for each cycle; Evaluating the stored measured temperatures over time; The method further comprises predicting the life of the belt using the stored measured temperature showing a maximum point as a criterion for judgment.

2. 1. A method for predicting belt life, comprising: The belt is a friction drive belt that includes rubber and is continuously driven. Measure the temperature of the belt while it is moving; Evaluating the measured temperature of the belt over time; The method of predicting the life of the belt using a criterion that the measured temperature of the belt exhibits a maximum point.

3. The method according to claim 1 or 2, wherein the measured temperature is a temperature measured at any one of an inner circumferential surface, an outer circumferential surface, and an interior of the belt.

4. A system for predicting belt life, comprising: a friction transmission belt including rubber, which repeats one cycle from the start of driving to the end of driving; A measuring unit for measuring the temperature of the belt during driving; a memory unit that stores a measured temperature of the belt at a predetermined time after the measured temperature of the belt reaches a set temperature for each cycle; A calculation unit that evaluates the measured temperatures stored in the memory unit over time; a prediction unit that predicts a life of the belt based on the evaluation result of the calculation unit, The prediction unit predicts the life of the belt using as a criterion whether the measured temperature stored in the memory unit indicates a maximum point.

5. A system for predicting belt life, comprising: a friction transmission belt including rubber and continuously driven; A measuring unit for measuring the temperature of the belt during driving; a calculation unit for evaluating the measured temperature of the belt over time; a prediction unit that predicts a life of the belt based on the evaluation result of the calculation unit, The prediction unit predicts the life of the belt based on a criterion that the measured temperature of the belt indicates a maximum point.

6. The system according to claim 4 or 5, wherein the measurement unit measures the temperature at any one of an inner circumferential surface, an outer circumferential surface, and an inside of the belt.

7. An RFID tag is embedded in the belt, The system of claim 6 , wherein the RFID tag comprises the measurement portion for measuring a temperature inside the belt.

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