Improvements in a sensor assembly and monitoring system for an idler roller

Abstract

A sensor assembly (200) comprises a body (110) with a protruding portion (216) for housing sensors (111, 218) that extends from the body, spaced apart from and adjacent to an idler roller (150). Another assembly (400) comprises a mechanism (402) for biasing a temperature sensor (403) into contact with the idler roller shaft (150) or bearing (130). Another assembly (500) comprises an acoustic or vibrational force sensor (218) and a spectral analyser (505) for processing the electric signal from the sensor when a processor is in a low power mode. A tool (300) for installing or removing another sensor assembly (100) having a shaft (115) for engaging the idler roller shaft (150) comprises a body (303) with a bore for receiving the sensor assembly; a mechanism (32) for clamping the sensor assembly; and an actuator (320) for moving the body into and out of the idler roller shaft (150).

Description

Improvements in a Sensor Assembly and Monitoring System for an Idler RollerField of the Invention

[0001] The invention relates to improvements to a sensor assembly and monitoring system for an idler roller and in a particular to improvements to a retrofittable sensor assembly for obtaining operational data relating to an idler roller. The invention has been developed primarily for use as a wireless sensor assembly and monitoring system for idler rollers in a belt conveyor system and will be described hereinafter by reference to this application.Background of the Invention

[0002] The following discussion of the prior art is intended to present the invention in an appropriate technical context and allow its advantages to be properly appreciated. Unless clearly indicated to the contrary, however, reference to any prior art in this specification should not be construed as an express or implied admission that such art is widely known or forms part of common general knowledge in the field.

[0003] A breakdown of a belt conveyor system for handling bulk material can be a serious problem. Each minute that the conveyor belt is out of operation can represent substantial economic losses. One particular component of the belt conveyor system which is regularly monitored to avoid unexpected shut down includes the bearings of the idler rollers.

[0004] For conveyor operations there are two primary modes of failure; firstly, high bearing temperature is a significant indicator of imminent idler roller ball bearing failure; secondly, thinning of the idler roller’s shell can lead to shell collapse and tearing of the conveyor belt. A common method for monitoring idler roller ball bearing temperature in bulk handling conveyors uses hand-held non-contact thermometers. As operators “walk” the conveyor line they often also listen for audible wear signals, such as, the bearing’s screaming. However, this approach is dangerous, time consuming, inaccurate, and labour intensive.

[0005] An alternative approach to monitoring the idler roller ball bearings is to embed sensors in the conveyor belt to sense the idler roller casing. This approach isdisadvantageous as it requires substantial and uncertain modelling of the thermal transfer of the ball bearing to idler roller casing and then idler roller casing to the conveyor belt. This requirement to model numerous belt conveyor system parameters naturally leads to inaccurate monitoring of the wear of idler rollers.

[0006] In response to one or more of these problems, one of the co-applicants had developed a sensor assembly and monitoring system for an idler roller in a belt conveyor system, as described in WO 2021 / 026606 A1, the disclosure of which is hereby incorporated by reference in its entirety. While the sensor assembly and monitoring system addresses these problems, further improvements or enhancements to these sensor assemblies and monitoring systems are desirable.

[0007] It is an object of the present invention to overcome or substantially ameliorate one or more of the disadvantages of prior art, or at least to provide a useful alternative. It is an object of the invention in at least one preferred form to provide an improved wireless sensor assembly and monitoring system for an idler roller in a belt conveyor system, that improve the accuracy of sensor measurements or the ease of installation and / or removal. In preferred embodiments, these improvements can be applied to either sensor assemblies embedded into the roll of the idler roller or alternately retrofitted onto the roller idler shaft or frame.Summary of the Invention

[0008] A first aspect of the invention provides a sensor assembly for an idler roller in a belt conveyor system, comprising: a body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; and a processor in communication with the one or more sensors and the wireless communication device; a shaft for engaging a shaft of the idler roller, wherein the shaft is connected to the body; wherein the one or more sensors transmit the detected parameter data to the processor; and the processer causes the detected parameter data to be transmitted by the wireless communication device.

[0009] In one or more embodiments, the shaft frictionally engages an outer surface of the idler roller shaft. In one or more embodiments, the shaft is sleeved into the idler roller shaft.

[0010] In one or more embodiments, the shaft comprises a collar, wherein the collar is configured to engage a tool for installing or removing the sensor assembly. In one or more embodiments, the collar comprises one or more recesses around its circumference for receiving clamping elements of the tool. In one or more embodiments the collar comprises a flange at one end of the shaft.

[0011] In one or more embodiments, the sensor assembly comprises a cover engageable with the body for protecting the one or more sensors, the wireless communication device and the processor. In one or more embodiments, the cover engages the shaft.

[0012] In one or more embodiments, the body is sealed to prevent the ingress of contaminants. In one or more embodiments, the cover is also sealed to prevent the ingress of contaminants

[0013] In one or more embodiments, a protective material is injected into a space between the body and the cover to protect the one or more sensors, the wireless communication device and the processor. In one or more embodiments, the protective material comprises a polymeric resin or equivalent material such as, polyurethane. In one or more embodiments, the one or more sensors, wireless communication device and processor are encapsulated or embedded in the protective material.

[0014] In one or more embodiments, the sensor assembly comprises one or more seals to protect the one or more sensors, wireless communication device and processor from contaminants.

[0015] In one or more embodiments, the sensor assembly is mounted to a mechanical seal of the idler roller. In other embodiments, the mechanical seal comprises a labyrinth seal.

[0016] In one or more embodiments, the one or more sensors perform one or more measurements of the parameters of the idler roller.

[0017] In one or more embodiments, the body is substantially annular in shape or has a ring-shape to define a central opening through which to receive the shaft of the sensor assembly and / or shaft of the idler roller. Similarly, in one or more embodiments, the cover is substantially annular in shape or has a ring-shape to define a central opening through which to receive the shaft of the idler roller and / or the shaft of the sensor assembly.

[0018] In one or more embodiments, the body comprises a substrate onto which is mounted the processor. In other embodiments, the one or more sensors are mounted on the substrate. In a further embodiment, the wireless communication device is mounted on the substrate.

[0019] In one or more embodiments, the substrate comprises a circuit board for the processor. In other embodiments, the substrate conforms to the shape of the body. In a further embodiment, the substrate is substantially annular in shape or ring shaped.

[0020] In one or more embodiments, the one or more sensors comprise one or more of: a temperature sensor, a rotation counter, a rotational velocity sensor, a vibration sensor, an accelerometer and an acoustic sensor.

[0021] In one or more embodiments, the one or more sensors comprise a temperature sensor for obtaining a temperature measurement indicative of the temperature of the idler roller. In one preferred embodiment, the temperature measurement is indicative of the temperature of a bearing of the idler roller. In other embodiments, the temperature sensor comprises a temperature probe. In further embodiments, a thermal transfer element is provided between the temperature sensor and the bearing. In one preferred embodiment, the thermal transfer element is a thermal washer.

[0022] In one or more embodiments the temperature sensor comprises a biasing mechanism for biasing the temperature sensor into contact with the idler roller to measure the temperature of the idler roller. In one or more embodiments, the biasing mechanism biases the temperature sensor into contact with the idler roller, preferably a shaft of the idler roller or bearing of the idler roller. In one or more embodiments, the biasing mechanism comprises a sensor holder for receiving the temperature sensor and a spring engageable with the sensor holder to urge the sensor holder towards the idler roller shaft or bearing. In one or more embodiments, the biasing mechanism comprisesa base engageable with the spring, wherein the spring is located between the sensor holder and the base. In one or more embodiments, the biasing mechanism comprises a housing for receiving the sensor holder and spring, wherein the sensor holder and temperature sensor slidingly move within the housing to and away from the idler roller.

[0023] In one or more embodiments, the one or more sensors comprise a rotation counter for measuring the rotations of a bearing of the idler roller. In further embodiments, the rotation counter comprises a magnetic based rotation counter. In other embodiments, the rotation counter comprises one or more magnetically responsive elements operatively connected to two or more magnets. In one embodiment, the two or more magnets are mounted to a magnet holder, and preferably the magnet holder is substantially annular in shape or ring shaped. In one or more embodiments, the magnet holder is affixed to one side of a seal of the sensor assembly. In yet another embodiment, the one or more magnetically responsive elements comprise magnetically responsive coils, which are preferably mounted to a substrate of the sensor assembly. In yet further embodiments, the one or more magnetic responsive coils detect the rotation of the one or more magnets. In a further embodiment, the rotational velocity of the idler roller is calculated from the detected rotation of the two or more magnets.

[0024] In one or more embodiments, the one or more sensors comprise an accelerometer for measuring acceleration of the idler roller in one or more axes. For example, one axis may be coincident with or parallel to the longitudinal axis of the idler roller. In another example, one of the axes may be a reference axis, in the horizontal or vertical plane. From this measurement, low frequency vibrations experienced by the idler roller can be calculated.

[0025] In one or more embodiments, the one or more sensors comprise an acoustic sensor for measuring acoustic data relating to the idler roller. From this measurement, low and high frequency vibrations experienced by the idler roller can be calculated.

[0026] In one or more embodiments, the one or more sensors comprise a vibration sensor measuring vibrations experienced by the idler roller. From this measurement, low and high frequency vibrations experienced by the idler roller can also be calculated.

[0027] In one or more embodiments, the sensor assembly comprises an energy harvesting mechanism for converting rotational movement of the sensor assembly intoelectrical energy to charge and / or recharge an energy storage device. Preferably, the energy storage device comprises a battery or a super-capacitor.

[0028] In one or more embodiments, the energy harvesting mechanism comprises a plurality of permanent magnets operatively coupled to one or more energy harvesting coils for converting rotational movement of the permanent magnets into electrical energy. In further embodiments, the one or more energy harvesting coils count the rotation of the permanent magnets and passes this information (being the rotation count data) to the processor. In one or more embodiments, the rotational velocity of the idler roller is calculated from the measured rotation by the one or more energy harvesting coils.

[0029] In one or more embodiments, the rotational velocity of the idler roller is compared to the rotational velocity of one or more idler rollers in the belt conveyor system to determine the relative shell thickness of the idler roller. The shell thickness is the thickness of the roll of the idler roller. Preferably, the rotational velocity of the idler roller is compared to the rotational velocity of an adjacent idler roller to determine the relative shell thickness of the idler roller.

[0030] In one or more embodiments, the absolute shell thickness is calculated from the rotational velocity of the idler roller and the external shell radius. In other embodiments, the external radius of the idler roller is determined by comparing the belt speed of a conveyor belt with the rotational velocity of the idler roller. In yet another embodiment, the external radius of the idler roller is estimated by comparing rotational velocities of the idler roller and using rotational velocities of a lower rpm for estimating the conveyor belt speed, and consequently the shell or roll diameter. In a further embodiment, historical data is utilised to calculate the external radius of the idler roller by comparing the measured rotational velocity of the idler roller to the rotation velocity of the idler roller when it was (first) installed.

[0031] In one embodiment, the sensor assembly is located adjacent an outer face of a labyrinth seal of the idler roller. In one or more embodiments, the outer face of the labyrinth seal is a “dirty” side of the labyrinth seal. Where the sensor assembly comprises a temperature sensor, the temperature sensor extends from a bearing of the idler roller through a stationary portion of the labyrinth seal.

[0032] In one or more embodiments, the sensor assembly is located adjacent an inner face of a labyrinth seal of the idler roller. In these embodiments, the inner face of the labyrinth seal is a “clean” side of the labyrinth seal. Where the sensor assembly comprises a temperature sensor, the temperature sensor is located adjacent to the bearing of the idler roller or the shaft of the idler roller.

[0033] In one or more embodiments, the processor comprises a microprocessor or microcontroller.

[0034] In one or more embodiments, the detected parameter data comprises measurements of the parameters of the idler roller.

[0035] In one or more embodiments, the parameters of the idler roller comprise the bearing temperature, the number of rotations, the rotational velocity and vibrations relating to the idler roller.

[0036] In one or more embodiments, the wireless communication device broadcasts the detected parameter data. In some embodiments, the wireless communication device comprises a transmitter for enabling simplex communication. In other embodiments the wireless communications device comprises a transceiver or a radio containing both a transmitter and receiver, for enabling half duplex communication. In other embodiments, the wireless communication device comprises a transceiver, radio transmitter or receiver. In further embodiments, the wireless communication device comprises an antenna.

[0037] In one or more embodiments, the sensor assembly comprises a transponder. In one or more embodiments, the sensor assembly comprises a fully encapsulated transponder. Preferably, the transponder is fully encapsulated transponder in a protective resin.

[0038] A second aspect of the invention provides a sensor assembly for an idler roller in a belt conveyor system, comprising: a body for fitting to a shaft of the idler roller, the body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; anda processor in communication with the one or more sensors and the wireless communication device; and a protruding portion for housing the one or more sensors; wherein the one or more sensors transmit the detected parameter data to the processor; the processer causes the detected parameter data to be transmitted by the wireless communication device; and the protruding portion extends from the body such that the protruding portion is spaced apart from and adjacent to the idler roller such that the one or more sensors able to detect the one or more parameters of the idler roller.

[0039] In one or more embodiments, the protruding portion is adjacent to an end of the idler roller. In one or more embodiments, the protruding portion extends towards the end of the idler roller. In one or more embodiments, the end of the idler roller comprises an end face of a roll of the idler roller.

[0040] In one or more embodiments, the body comprises a first shell portion and a second shell portion connectable together to form a protective shell. In one or more embodiments, the protruding portion is connected to at least one of the first shell and second shell portions. Alternatively, in one or more embodiments, the protruding portion is integrally formed with the at least one of the first shell and second shell portions. In one or more embodiments, the protruding portion comprises a raised portion from the at least one of the first shell and second shell portions.

[0041] In one or more embodiments, the protruding portion has a square or rectangular shape. In one or more embodiments, the protruding portion comprises a fin- like body or beak.

[0042] In one or more embodiments, the sensor assembly comprises a first set of one or more magnets for mounting the body to a frame of the idler roller and / or the shaft of the idler roller. In one or more embodiments, the first set of one or more magnets are mounted to an exterior surface of the body.

[0043] In one or more embodiments, a second set of one or more magnets is mountable to the idler roller, wherein movement of the second set of one or more magnets is detected by a magnetic sensor in the protruding portion. The magneticsensor is preferably the rotation counter. In one or more embodiments, the second set of one or more magnets are mounted to an end face of the idler roller.

[0044] In one or more embodiments, the sensor assembly comprises a cover is mounted to the idler roller to protect the second set of one or more magnets.

[0045] In one or more embodiments, the body is substantially annular in shape or has a ring-shape to define a central opening through which to receive the shaft of the idler roller. Similarly, in one or more embodiments, the first shell portion and the second shell portion are each substantially annular in shape or has a ring-shape to define a central opening through which to receive the shaft of the sensor assembly.

[0046] In one or more embodiments, the body is substantially square or rectangular in shape for fixing to the shaft or a frame of the idler roller.

[0047] One or more embodiments of the second aspect may have the features of one or more embodiments of the first aspect of the invention stated above, where applicable. For example, one or more embodiments of the second aspect may have the features of the shaft of the first aspect and / or the various sensors, processor and wireless communication device as described above.

[0048] A third aspect of the invention provides a temperature sensor assembly for an idler roller in a belt conveyor system, comprising: a temperature sensor for measuring the temperature of the idler roller: and a biasing mechanism for biasing the temperature sensor into contact with the idler roller.

[0049] In one or more embodiments, the biasing mechanism biases the temperature sensor into contact with a shaft of the idler roller. In one or more embodiments, the biasing mechanism biases the temperature sensor into contact with a bearing of the idler roller. In one or more embodiments the biasing mechanism comprises a spring.

[0050] In one or more embodiments, the temperature sensor assembly comprises a sensor holder for receiving the temperature sensor. In one or more embodiments, the biasing mechanism is engageable with the sensor holder to urge the sensor holder towards the idler roller.

[0051] In one or more embodiments, the temperature sensor assembly comprises a base engageable with the biasing mechanism, wherein the biasing mechanism is located between the sensor holder and the base. In one or more embodiments, the temperature sensor assembly comprises a housing for receiving the sensor holder and biasing mechanism, wherein the sensor holder and temperature sensor slidingly move within the housing. The sensor holder and / or temperature sensor may slidingly move to and away from the idler roller from the base.

[0052] A fourth aspect of the invention provides a sensor assembly for an idler roller in a belt conveyor system, comprising: a body for fitting to a shaft of the idler roller, the body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; and a processor in communication with the one or more sensors and the wireless communication device; wherein the one or more sensors transmit the detected parameter data to the processor; the processer causes the detected parameter data to be transmitted by the wireless communication device; and at least one of the one or more sensors comprises the temperature sensor assembly of the third aspect for measuring the temperature of a bearing of the idler roller.

[0053] One or more embodiments of the fourth aspect may have the features of one or more embodiments of the first, second and / or third aspects of the invention stated above, where applicable. In particular, one or more embodiments of the fourth aspect may have the features of the biasing mechanism described above in relation to the third aspect. Also, for example, one or more embodiments of the fourth aspect may include one or more features of the shaft of the first aspect, the protruding portion of the second aspect and / or the various sensors, processor and wireless communication device as described above.

[0054] A fifth aspect of the invention provides a tool for installing or removing a sensor assembly of the first aspect to and from an idler roller in a belt conveyor system, comprising:a tool body having a bore for receiving the sensor assembly: a clamping mechanism for clamping the seal assembly; and an actuator for moving the tool body into and out of a shaft of the idler roller for positioning the sensor assembly into engagement with the idler roller or removing the sensor assembly from engagement with the idler roller.

[0055] In one or more embodiments, the clamping mechanism comprises one or more clamping elements for engaging the body of the sensor assembly. In one or more embodiments, the one or more clamping elements are arranged around the circumference of the tool body.

[0056] In one or more embodiments, the tool body has one or more openings in communication with bore such that the one or more clamping elements extend through the openings into the bore to engage the body of the sensor assembly.

[0057] In one or more embodiments, the one or more clamping elements comprise movable fasteners. In one or more embodiments, the movable fasteners comprise screws. In one or more embodiments, the screws are arranged to extend radially into the tool body bore.

[0058] In one of more embodiments, the actuator comprises a screw or piston. In one or more embodiments, the actuator comprises a stop to limit movement of the tool body in the shaft of the idler roller. In one or more embodiments, the stop comprises a flange or plate at one end of the actuator.

[0059] A sixth aspect of the invention provides a method of installing the sensor assembly of the first aspect to an idler roller in a belt conveyor system using the tool of the fifth aspect, comprising: removing an end cap from the idler roller; operating the clamping mechanism to clamp the sensor assembly to the tool body; operating the actuator to move the tool body into a bore of a shaft of the idler roller to a desired location; operating the clamping mechanism to release the sensor assembly from the tool body;operating the actuator to withdraw the tool body from the shaft of the idler roller; and replacing the end cap on the idler roller.

[0060] A seventh aspect of the invention provides a method of removing assembly of the first aspect from an idler roller in a belt conveyor system using the tool of the fifth aspect, comprising: removing an end cap from the idler roller; operating the actuator to move the tool body into a bore of a shaft of the idler roller to a desired location; operating the clamping mechanism to clamp the sensor assembly to the tool body; operating the actuator to move the sensor assembly into the bore of the tool body; and operating the actuator to withdraw the tool body from the shaft of the idler roller.

[0061] In one or more embodiments, the method comprises replacing the end cap on the idler roller.

[0062] In one or more embodiments, the method comprises removing a mechanical seal from the idler roller prior to moving the tool body into the shaft of the idler roller. In one or more embodiments, the method comprises connecting the sensor assembly to the mechanical seal before operating the clamping mechanism to clamp the sensor assembly to the tool body. In this embodiment, the connected sensor assembly and mechanical seal are installed by the tool, and can be removed together by the tool.

[0063] In one or more embodiments, the sensor assembly comprises a rotation counter and energy harvesting mechanism in the form of one or more magnetically responsive elements mounted to a substrate of the sensor assembly and operatively connected to two or more magnets mounted to a magnet holder, and the method further comprises mounting the substrate on one side of the mechanical seal and the magnet holder to an opposite side of the mechanical seal. In other embodiments, the mechanical seal comprises a labyrinth seal.

[0064] In one or more embodiments, the method further comprises connecting the wireless communication device to a receiver for communicating with a central processing unit, wherein the central processing unit analyses the detected parameter data. In other embodiments, the receiver comprises a data link and the central processing unit executes diagnostic processing software to analyse the detected parameter data.

[0065] One or more embodiments of the sixth and / or seventh aspects may have the features of one or more embodiments of the preceding aspects of the invention stated above, where applicable. In particular, the embodiments of the sixth and / or seventh aspects may incorporate the features of one or more embodiments of the tool described in relation to the fifth aspect of the invention.

[0066] An eighth aspect of the invention provides an acoustic sensor assembly or a vibration sensor assembly for an idler roller in a belt conveyor system, comprising: a signal generator for generating an electric signal in response to an acoustic or vibrational force; and a spectral analyser for processing the electric signal when the processor is in a low power mode.

[0067] In one or more embodiments, the spectral analyser comprises one or more sample and hold circuits for processing the electric signal.

[0068] In one or more embodiments, the spectral analyser comprises one or more filters for converting the electric signal into discrete bands, wherein the output of each filter is fed to one of the sample and hold circuits. Preferably, the one or more filters are connected to a corresponding sample and hold circuit of the one or more sample and hold circuits.

[0069] In one or more embodiments, the spectral analyser comprises an amplifier for amplifying the electric signal from the signal generator.

[0070] In one or more embodiments, a filter bank removes noise from the electric signal after it passes through the amplifier. In one or more embodiments, the filter bank breaks or divides the electric signal into various diagnostic bands. The diagnostic bands each yields certain diagnostic significance.

[0071] In one or more embodiments, the signal generator comprises a transducer. In one or more embodiments, the transducer comprises a piezoelectric transducer.

[0072] A ninth aspect of the invention provides a sensor assembly for an idler roller in a belt conveyor system, comprising: a body for fitting to a shaft of the idler roller, the body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; and a processor in communication with the one or more sensors and the wireless communication device; wherein the one or more sensors transmit the detected parameter data to the processor; the processer causes the detected parameter data to be transmitted by the wireless communication device; and at least one of the one or more sensors comprises the vibration sensor assembly of the ninth aspect for measuring vibrations experienced by the idler roller or the acoustic sensor assembly of the ninth aspect for measuring acoustic data relating to the idler roller.

[0073] One or more embodiments of the ninth aspect may have the features of one or more embodiments of the preceding aspects of the invention stated above, where applicable. In particular, one or more embodiments of the nineth aspect may have the features of the vibration sensor assembly or the acoustic sensor assembly described above in relation to the eighth aspect. Also, for example, one or more embodiments of the ninth aspect may include one or more features of the shaft of the first aspect, the protruding portion of the second aspect, the temperature sensor assembly of the third aspect and / or the various sensors, processor and wireless communication device as described above.

[0074] A tenth aspect of the invention provides a telemetry-enabled seal assembly for an idler roller in a belt conveyor system, comprising a mechanical seal for mounting on a shaft of the idler roller and a sensory assembly connected to the mechanical seal, wherein the sensor assembly is in accordance with any one of the first, second, third, fourth and / or ninth aspects of the invention.

[0075] In one or more embodiments, the mechanical seal is a labyrinth seal, the body of the sensory assembly being connected to an inner face of the labyrinth seal. In other embodiments, the body of the sensory assembly is connected to an outer face of the labyrinth seal.

[0076] An eleventh aspect of the present invention provides a monitoring system for one or more idler rollers in a belt conveyor system, comprising: a sensor assembly according to any one of the first second, third, fourth and / or ninth aspects of the invention or a telemetry-enabled seal assembly according to the tenth aspect of the invention mounted to the one or more idler rollers; a receiver for receiving the detected parameter data from the wireless communication device; and a central processing unit in communication with the receiver for analysing the detected parameter data.

[0077] In one or more embodiments, the central processing unit is configured to compare the detected parameter data against one or more predetermined data thresholds; and in response to one of the detected parameter data passing one of the predetermined data thresholds, transmit a signal to alert replacement and / or repair of the idler roller associated with the one of the detected parameter data passing one of the predetermined data thresholds. In other embodiments, the central processing unit executes diagnostic processing software to analyse the detected parameter data.

[0078] In one or more embodiments, the central processing unit is configured to receive parameter data from one or more of the sensor assemblies at regular intervals. Alternatively, the central processing unit transmits a command to one or more of the sensor assemblies to report the detected parameter data in reply to the command.

[0079] In one or more embodiments, the receiver is physically remote to the sensor and / or idler roller. In further embodiments, the receiver is located in a communications hub for receiving detected parameter data from a plurality of sensors.

[0080] In some embodiments, the communication hub comprises a transceiver that aggregates and passes data to the central processing unit.

[0081] In some embodiments, there is a plurality of the communication hubs, each communication hub being connected to different sensor assemblies located in different idler rollers, wherein the central processing unit is in communication with the plurality of receivers.

[0082] In one or more embodiments, the central processing unit is located in the communications hub.

[0083] In one or more embodiments, the receiver comprises a transceiver and transmits commands from the central processing unit to the wireless communication device of the sensor assembly.

[0084] In one or more embodiments, there is a plurality of receivers, each connected to different sensor assemblies located in different idler rollers, wherein the central processing unit is communication with the plurality of receivers.

[0085] In a twelfth aspect there is provided a belt conveyor system comprising a plurality of idler rollers, a plurality of sensor assemblies according to any one of the first second, third, fourth and / or ninth aspects of the invention or a plurality of telemetry- enabled seal assemblies according to the tenth aspect of the invention and the monitoring system according to the eleventh aspect, wherein there is a plurality of receivers in communication with the central processing unit, each connected to different sensor assemblies or telemetry-enabled seal assemblies located in different idler rollers.

[0086] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

[0087] Furthermore, as used herein and unless otherwise specified, the use of the ordinal adjectives "first", "second", "third", etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.Brief Description of the Drawings

[0088] Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0089] Figure 1 A is a cross-sectional view of the sensor assembly of Figure 1A installed on an idler roller in a belt conveyor system;

[0090] Figure 1 B is an exploded perspective view of a sensor assembly according to one embodiment of the invention;

[0091] Figure 2A is an exploded perspective view of a sensor assembly according to another embodiment of the invention;

[0092] Figure 2B is a cross-sectional plan view of the sensor assembly of Figure 2A installed on an idler roller in a belt conveyor system;

[0093] Figure 2C is a cross-sectional side view of the sensor assembly of Figure 2A installed on an idler roller in a belt conveyor system;

[0094] Figure 2D is a perspective view of a portion of the sensor assembly of Figure 2A;

[0095] Figure 2E is a perspective view and Figure 2F is a plan view of a cover for use with the sensor assembly of Figure 2A;

[0096] Figure 3A is a perspective view of a tool for installing and removing the sensor assembly of Figure 1 A according to a further embodiment of the invention;

[0097] Figure 3B is an end view of the tool of Figure 3B;

[0098] Figure 4A is a cross-sectional view of a temperature sensor assembly according to a preferred embodiment of the invention;

[0099] Figure 4B is an exploded view of temperature sensor assembly of Figure 4A;

[0100] Figure 5A is a schematic drawing of a spectral analyser for an acoustic sensor assembly or a vibration sensor assembly according to another preferred embodiment of the invention; and

[0101] Figure 5B is a graph illustrating the spectral response of the spectral analyser of Figure 5B.Preferred Embodiments of the Invention

[0102] The present invention will now be described with reference to the following examples which should be considered in all respects as illustrative and non-restrictive. Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms. In the Figures, corresponding features within the same embodiment or common to different embodiments have been given the same reference numerals.

[0103] Referring to Figure 1A, the various aspects and their respective embodiments of the invention have been developed for measuring various parameters of a plurality of conveyor idler rollers 1 for supporting a conveyor belt (not shown) in a belt conveyor system, each idler roller having bearings 130, a bearing ring 135, a mechanical seal 140, an idler roller shaft 150 and a roll or shell 160. The idler roller 1 is supported by the roller shaft 150 mounted on support brackets (not shown).

[0104] Referring to Figures 1A and 1B, a sensor assembly 100 according one embodiment of the invention is shown and takes the form of a transponder is shown, mounted to at least one end of the idler roller 1. As best shown in Figure 1A, the transponder 100 is placed adjacent to an inner side of a mechanical seal in the form of a labyrinth seal 140. In this configuration, the transponder 100 is located on the “clean” side of the labyrinth seal 140. This helps provide a cleaner operational environment for the transponder 100, although in practice the internal components of the transponder may be protected by being enclosed in a semi-rigid encapsulant which provides the majority of ingress protection.

[0105] In this configuration, the labyrinth seal 140 in combination with the transponder 100 becomes a telemetry enabled seal. As such, the telemetry-enabled labyrinth seal can be used as an installed component into an idler roller 1 or a direct replacement for an existing labyrinth seal in an idler roller 1 in a pre-existing conveyor system. It will beappreciated that the transponder 100 can be incorporated into any type of mechanical seal used with an idler roller and is not limited to a labyrinth seal.

[0106] Referring to Figure 1 B, the transponder 100 comprises an annular or ringshaped body 110 and a shaft 115 for engaging the 150 of the idler roller 1 , the shaft being connected to the body 110. An inner surface 117 of the shaft 115 frictionally engages an outer surface 118 of the idler roller shaft 150. Ideally, the shaft 115 is sleeved onto the idler roller shaft 150.

[0107] The shaft 115 provides a convenient carrier for the transponder 100, facilitating installation and removal through the use of a tool as described in more detail below. In this embodiment, the shaft 115 comprises a collar 119, which is configured to engage a tool for installing or removing the sensor assembly 100. The collar takes the form of a flange 119 at one end of the shaft 115. Preferably, the collar 119 may comprise recesses (not shown) around its circumference for receiving clamping elements of the tool. .

[0108] The transponder body 110 also comprises various sensors, such as rotation sensor 111 for detecting parameters or characteristics of the idler roller, a processor in the form of a microcontroller (not shown) and a wireless communication device in the form of a transceiver (not shown) and one or more antennae 112. The parameters or characteristics of the idler roller 10 relate to operational or physical aspects of the idler roller 10, such as, but not limited to, temperature of the bearings 130, rotational speed of the idler roller, shell thickness of the idler roller, vibrations experienced by the idler roller, number of rotations of the idler roller and ambient noise.

[0109] The transponder 100 has a temperature sensor, the rotation sensor 111, an acoustic sensor, a vibration sensor and an accelerometer. The temperature sensor will be described in more detail below in relation to Figures 4A and 4B. The accelerometer measures the acceleration of the idler roller 1 and hence the low frequency vibrations being experienced by the idler roller 1. Similarly, the vibration sensor and acoustic sensor also measure low and high frequency vibrations, the acoustic sensor indirectly by way of measuring acoustic data. These vibration measurements can be an early warning sign of an upcoming fault in the bearing 130 of the idler roller 1.

[0110] The transponder body 110 preferably comprises a substrate in the form of a printed circuit board onto which is mounted several electronic components, including a super-capacitor 122, the battery 113, the microcontroller (not shown), the transceiver (not shown) and the antenna(e) 112. A programming header 125 is also provided to install the initial transponder firmware and possibly field updates. The programming header is in a prominent location to assist access via a thinned window (not shown) that can be ruptured and resealed). The thinned window is placed in a cover 120, which will be discussed in more detail below. The battery 113 provides energy to power the microcontroller and transceiver whilst the idler roller 10 is laying idle. Additionally, the super-capacitor assists 122 in meeting the short-term energy demand of the transceiver.

[0111] The rotation sensor comprises magnetically responsive elements in the form of energy harvesting coils 111 and a plurality of permanent magnets (not shown) that can be mounted to a magnet boss. The energy harvesting coils 111 act as an energy harvesting system for converting rotational movement of the permanent magnets into electrical energy which is then stored in the battery 113. Thus, the energy harvesting coils 111 provide the electrical current required to keep the super-capacitor charged whilst the idler roller 1 is in motion. This electrical current is induced in the energy harvesting coils 140 as the permanent magnets rotate past. When the idler roller 1 is rotating at a sufficient velocity, the steady state energy requirements of the transceiver are satisfied by the charge held in the super-capacitor. However, if the rotational velocity of the idler roller 1 is insufficient, then the steady state energy requirements of the transponder 110 are met by the battery 113.

[0112] The microcontroller of the transponder body 110 comprises a processor, a memory, and an input / output interface coupled together via a bus. The memory comprises both a non-volatile memory and volatile memory. The non-volatile memory can store a computer program embodied in the form of executable instructions for executing commands and generating sensor data based on the sensor measurements received from the sensors. The transponder 100 periodically broadcasts the sensed data via the transceiver, which in other embodiments may be a radio transmitter. The electrical signals from transceiver are converted into electromagnetic waves via the antenna(e) 112. The internal microcontroller may be configured to read parameter data from the sensors at regular intervals. This parameter data is then in turn transmitted to a local Access Point using microwave wireless communications via the antenna(e) 112.

[0113] It should be noted that the wireless communication device may comprise a transmitter for enabling simplex communication. Alternatively, the wireless communications device comprises a transceiver or a radio containing both a transmitter and receiver, for enabling half duplex communication.

[0114] The energy harvesting coils 111 are also used to count how many times the permanent magnets pass the energy harvesting coils 111 and pass on this information to the processor. This count provides an accurate measure of the number of rotations of the idler roller 1 and the rotational velocity of the idler roller is calculated from the measured rotation by the one or more energy harvesting coils. The number of counts per revolution is dependent on the particular configuration of the energy harvesting coils 111 and the permanent magnets.

[0115] As the shell 160 of the idler roller 135 begins to wear, its rotational velocity will increase for a given linear velocity (i.e. the speed) of the conveyor belt. By comparing the rotational velocity of the idler roller with the linear velocity or belt speed of the conveyor belt, shell thickness of the idler roller can be calculated by the following relationship:Shell Thickness = 1000 x Belt Speed - Inner Diameter fl x RPMWhere: Shell Thickness is in millimetresInner Diameter of shell is in metresBelt Speed is linear speed in metres / minuteRPM is rotational speed of idler roller in Revolutions Per Minute fl is the ratio of a circle’s circumference to its diameter

[0116] In one example, the belt speed is measured by using an auxiliary idler roller in the return path of the conveyor belt. Alternatively, the belt speed may be obtained from the head-end drive pulley speed.

[0117] This rotational data can be compared to the rotational data of other nearby or adjacent idler rollers. This roller RPM data can be used to estimate the conveyor belt speed by measuring the lowest RPM (and therefore the largest idler roller) and making the assumption that at least one of the idler rollers has a diameter close to the manufacturer’s specifications. Alternatively, if a conveyor belt signal is available, this can be used directly with individual rpm measurements to determine individual idler roller wear. No prior knowledge, such as, belt speed, is assumed except at least one idlerroller has a diameter close to the nominal idler roller diameter. The weighting function can be used to select larger diameter idler rollers and ignore data from more narrow idler rollers, for the purposes of calculating a mean value skewed towards larger idler rollers. This follows a similar shape to that of a Poisson distribution (1 / x). As high precision is required for the prediction of idler roller diameters, analysis is performed on data collected over several hours.

[0118] The external radius of the idler roller 1 may be estimated by comparing rotational velocities of the idler roller and using rotational velocities of a lower RPM for estimating the conveyor belt speed, and consequently the shell or roll diameter. In addition, historical data of the measured parameters of the idler roller may be used to calculate the external radius of the idler roller by comparing the measured rotational velocity of the idler roller to the rotation velocity of the idler roller when it was (first) installed.

[0119] The accelerometer may be coupled to or integrated with the microcontroller. In this configuration, at least some of the sensor data generated by the microcontroller is indicative of vibration data, preferably low-frequency vibration data. The transponder 100 may only generate sensor data indicative of the vibration data, preferably low-frequency vibration data, in response to receiving an external request to provide acceleration data. Alternatively or additionally, the transponder 100 periodically broadcasts acceleration data via the transceiver and antenna(e) 112.

[0120] Similarly, the vibration sensor and acoustic sensor may be coupled to or integrated with the microcontroller. As described above, the transponder 100 broadcasts sensor data indicative of the vibration and / or acoustic data periodically or only in response to an external request communicated to the transponder. In either case, the vibration and / or acoustic data is transmitted or broadcast data via the transceiver and antennae 112. A unique configuration of the vibration sensor and acoustic sensor according to a further embodiment of the invention will be described in more detail below.

[0121] In some exemplary configurations, a series of discrete sensor measurements can be obtained over a period of time by the transponder 100 and transmitted or reported by the transceiver. In particular, a request can be made to the transponder 100, wherein the command includes a request for a series of discrete sensor measurements for a predetermined period of time. For example, the series of discrete sensor measurementsmay be obtained every minute for a one-hour period. The command may also be a request that a selection of the one or more sensors to generate the series of discrete sensor measurements. For example, a request may be sent to the transponder 100 that only the temperature sensor and the accelerometer provide discrete sensor measurements, whereas the other sensors may remain idle, report at different frequencies or time periods, or only in response to a threshold measurement value. For example, if the temperature sensor measures a threshold value of above the bearing’s recommended operating temperature that indicates that imminent failure is likely, the microcontroller will automatically report this measured value via the transceiver without requiring a request.

[0122] The transponder 100 also comprises a cover 120 engageable with the body 110 for protecting the sensors, the wireless communication device and the processor. In this embodiment, the cover 120 engages the shaft 115, preferably by sliding over the shaft to engage the transponder body 110. The cover 120 assists with the protection of the transponder circuit assembly on the substrate 110 from damage as it shields the electronic components. In situations where it is desirable for additional protection, the electronic components may be fully encapsulated by using the cover 120 and collar 119 with some suitable tape to create a mould form for contain the encapsulant. Accordingly, the body 110 and cover 120 are sealed to prevent the ingress of contaminants.

[0123] A protective material is injected into a space between the body 110 and the cover 120 to protect the sensors, the wireless communication device and the processor. The protective material may comprise a polymeric resin or equivalent, such as polyurethane. In this case, the sensors, wireless communication device and processor are encapsulated or embedded in the protective material.

[0124] As an alternative to an encapsulant, the transponder may use one or more seals to protect the sensors, wireless communication device and processor from contaminants.

[0125] In other embodiments, where the transponder 100 is incorporated into a telemetry-enabled labyrinth seal, it may be mounted on the “dirty” side (i.e. externally, outwardly or outer facing side relative to the idler roller 1 and conveyor) of the labyrinth seal 140. In this case, the whole assembly may be protected by a dustcover and optionally some form of encapsulant or conformal coating.

[0126] Irrespective of whether the transponder body 110 is located adjacent the clean or dirty side of the labyrinth seal 140, where a permanent magnet retaining boss is used, it is generally located on the opposite side of the labyrinth seal to the transponder body 110, which in this particular embodiment uses the coils 111 for energy harvesting. In this way, the permanent magnets will pass the energy harvesting coils 111 when the idler roller 1 rotates.

[0127] It is intended that the telemetry enabled seal incorporating the sensor assembly / transponder 100 be used by conveyor operators and manufacturers as a replacement for current labyrinth seals. The transponder body 110 can be affixed to either side of the labyrinth seal 140 by way of adhesive, a suitable fastener or clip detail. In the same way, the permanent magnet retaining boss can be affixed to the opposite seal component of the labyrinth seal 140 by way of adhesive, a fastener or clip detail. If there is a spatial constraint making it difficult to locate the transponder body 110 then an oversized retrofit dust cover can then be fitted over the transponder body to protect the printed circuit board, sensors and electrical components. The dust cover would also comprise a central opening or hole to receive the shaft 150 of the idler roller 1. Whilst some additional space above the transponder body 110 can be made available by changing the shape of the dustcover, it is preferable that the dust cover avoid interfering with the idler roller bracket.

[0128] It will be appreciated that the sensor assembly 115 (either as part of a telemetry-enabled labyrinth seal assembly or as a modification to an existing labyrinth seal) can be installed at opposing ends of an idler roller 1 to obtain sensor data 460 for both bearings 135 at the opposing ends of the idler roller 1. The transponder 100 is preferentially fitted on both ends of each conveyor roll 1 during manufacture, alternatively a plurality of transponders 100 may be retrofitted using a tool 300 (to be described in more detail below) to one or both sides of a plurality of idler rollers 1 , thus obtain sensor data for at least some or all idler rollers.

[0129] Referring to Figures 2A to 2C, a sensor assembly or transponder 200 according to another embodiment of the invention is illustrated, which is adapted for mounting to a frame in the form of support bracket 250 and / or shaft 150 of the idler roller 1. The sensor assembly 200 comprises an annular or ring-shaped body 110 in the form of a substrate or printed circuit board and a protruding portion or section 216 housing at least one or more sensors. The transponder 200 may have a circular, overall square orrectangular in shape for fixing to the shaft 150 or frame 250 of the idler roller 1. The protruding portion 216 extends from the transponder body 110 such that the protruding portion is spaced apart from and adjacent to an end 217 of the idler roller such that the sensors able to detect the one or more parameters of the idler roller.

[0130] In this embodiment, the transponder 200 comprises a first casing or shell portion 210 and a second casing or shell portion 220. The shell portions 210, 220 form a protective casing or shell 225 that sandwiches the transponder body 110 between the first shell portion 210 and the second shell portion 220. The shell 225 thus protects the transponder 200 from impacts and ingress of contaminants. Preferably, the transponder body 110 is mounted to one of the shell portions, preferably the shell portion closest to the idler roller, which would be the first shell portion 210. The second shell portion 220, being furthest away from the idler roller 1 , is preferably configured so as to not impede microwave radio propagation to enable the antenna(e) 112 to transmit parameter data. Consequently, it is preferred that the antennae 112 are located under the second shell portion 220.

[0131] The protruding portion 216 is integrally formed with the shell 225. In this embodiment, the protruding portion 216 is integrally formed with the first shell portion 210, but in other embodiments could be integrally formed with the second shell portion 220. Alternatively, the protruding portion 216 may be connected to either of the first shell and second shell portions 210, 220.

[0132] In this embodiment, the protruding portion 216 extends towards the end 217 of the idler roller 1, which also constitutes an end face. The protruding portion 216 has in this embodiment a fin-like body or “beak”. This enables the protruding portion to project forward close to the idler roller to acquire parameter data through the sensors housed in the protruding portion 216.

[0133] Referring to Figure 2C, the sensors housed within the protruding portion 216 are illustrated, and comprise a magnetic sensor 211 , a combined acoustic and vibration sensor 218 and a thermal or temperature sensor 400. The magnetic sensor 211 is used to detect the RPM of the conveyor idler roller 1. The protruding portion 216 ensures that these sensors are as close as possible to the end face 217 of the idler roller 1 without actually contacting the rotating surfaces of the idler roller. However, not all the sensors need to be located in the protruding portion 216. For example, a vibration sensor oraccelerometer may be located on the substrate 100 to detect vibration or other sub-sonic signals that are transferred through the shell portion 210 closest to the idler roller 1.

[0134] In this embodiment, the transponder 200 is affixed to the idler roller frame, or similar support bracket or fixture (which may be present in garland type idler rollers that tend to have associated supports and links) where the bearing temperature can be closely approximated by sensing the temperature of the idler roller shaft 150 near where the idler roller shaft passes through the frame or support, like support bracket 250. Providing the temperature sensor 400 in the protruding portion 216, results in higher accuracy in the measured temperature, as the sensing point is closer to the source of heat (namely the bearing and / or seal drag). It has been found in experimental tests that there is a high correlation in temperature measurements between placement of the temperature sensor 400 in the protruding portion 216 and placement of the temperature sensor inside the idler roller 1, as exemplified in Figures 1A and 1B.

[0135] The benefit of this configuration of the transponder 200 is that it can be readily installed to the bracket 250 and shaft 150 of the idler roller without having to open the end 217 of the idler roller, remove the mechanical seal and then install the transponder. Thus, installation and removal of the transponder 200 is quicker and less labour intensive. This also means that maintenance of the transponders 200 can be performed easily and quickly as they can be readily accessed from the support bracket 250, rather than having to stop the conveyor system and open each end of each idler roller 1.

[0136] The transponder 200 also comprises one or more magnets 215 for mounting the transponder to the bracket 250, as best shown in Figures 2C and 2D. There are four magnets 215 in this embodiment, which are fitted to an exterior face or surface 230 of the first shell portion 210, corresponding to the back of the first shell portion, as best shown in Figure 2D. The one or more magnets 15 are magnetically attracted to the support bracket 250 to secure the transponder 200 in place. An advantage of this particular arrangement is that it further enhances the ability to affix the transponder 200 to the idler roller 1 without removing it from the belt conveyor system. This approach further makes the installation of the transponder 200 even quicker, and enables several transponders to be added to a conveyor line per hour per installer, improving installation efficiency

[0137] Another set of one or more magnets 270 are connected or adhered to the end face 217 of the idler roller, preferably using glue or other adhesive. The magnets 270 are used to measure the rotational velocity of the idler roller 1. In this case, the magnets 270 on the end face 217 of the idler roller 1 are placed or located on or near the circumferential edge or rim of the idler roller. The magnetic sensor 211 in the protruding portion 216 and / or the coils in the first shell portion 210 detect the passing of the magnets 270 as they rotate with the idler roller 1 and hence its rotational velocity.

[0138] Referring to Figures 2E and 2F, a cover 260 is provided to help protect the magnets 270 at or near the rim of the idler roller 1 from environmental damage. The cover 260 is annular or ring-shaped to only cover the area occupied by the magnets 270 and is affixed over the end face 217 of the idler roller.

[0139] Referring to Figures 3A and 3B, another embodiment of the invention provides a tool 300 for installing and removing the transponder 100 of Figures 1A and 1 B. The tool 300 comprises a tool body 303 having a bore (not shown) for receiving the sensor assembly (i.e. transponder 100), a clamping mechanism 320 for clamping the sensor assembly; and an actuator 310 for moving the tool body into and out of the shaft 150 of the idler roller 1 for positioning the sensor assembly into engagement with the idler roller or removing the sensor assembly from engagement with the idler roller.

[0140] The clamping mechanism 320 may comprises one or more clamping elements for engaging the transponder 100. In this embodiment, there is a plurality of clamping elements in the form of movable screws 320, that are preferably arranged around the circumference of the tool body 303. The tool body 303 has one or more openings 325 in communication with the bore 305 such that the screws 320 extend through the openings into the bore to engage the transponder 100. In this embodiment, the screws 320 are arranged to extend radially into the tool body bore 305. It will be appreciated that in other embodiments, the clamping elements may comprise other movable fasteners, such as bolts or screw bolts.

[0141] The actuator 310 comprises a screw, preferably a pull screw, but may take other forms, such as a piston. The screw 310 has a stop 330 to limit movement of the tool body 303 in the shaft 150 of the idler roller 1. In this embodiment, the stop comprises a flange or plate 330 at one end of the actuator 310, as best shown in Figure 3B.

[0142] The radially mounted screws 320 are used to engage the transponder 100, preferably by clamping or biting into the collar 119. The collar 119 may have openings or recesses 101 to receiving the screws 320. Once engaged, the transponder 100 can be withdrawn off the idler roller shaft 150 using the puller screw 310 with minimal damage to the shaft surface. To help ensure precise fitting and registration of the transponder 100 inside of the tool bore 305, the end plate 330 ensures the transponder 100 is not pressed too deeply inside the idler roller 1.

[0143] The general sequence for installing the transponder 100 into the idler roller 1 is described as follows. A dustcover and / or end cap is removed from the idler roller 1 , thereby exposing a pre-existing or “old” labyrinth seal 140, which is then removed. The clamping mechanism, i.e. the radially extending screws are operated to clamp the transponder 100 to the tool body 303 within the bore 305. The pull screw 310 is then turned to insert the tool body 303 into the idler roller shaft 150 to the desired location.The end plate or flange 330 ensures that the transponder 100 is not inserted too far into the idler roller shaft 150. The screws 320 are then unwound to release the transponder 100, and the transponder is then fixed at the desired located by using one or more fasteners, an adhesive or clip. The screw 310 is then turned in the opposite direction to withdraw the tool body 303 out of the idler roller shaft 150. The labyrinth seal 140 is then returned and placed adjacent to the installed transponder 100. Where the labyrinth seal is to be replaced by a telemetry-enabled seal (i.e. the transponder 100 is connected to a labyrinth seal), telemetry-enabled seal is installed using the tool 300 by the above steps, where the screws 320 clamp the transponder 100 and not the labyrinth seal. The dustcover or end cap is then reinstalled on the idler roller shaft 150.

[0144] To remove the transponder 100 from the idler roller shaft 150, the above process is performed in reverse.

[0145] It will be appreciated that this method can be repeated for each end of the idler roller 1 so that both bearings 135 of the idler roller can be monitored. It will also be appreciated that the method can be repeated for multiple idler rollers 1 of the belt conveyor system. In this way, transponder 100 can be retrofittably mounted to either end of a conveyor idler roller 1 in the field or during manufacture.

[0146] Referring to Figures 4A and 4B, a temperature sensor assembly 400 according to a further embodiment of the invention is illustrated, where the temperature sensorassembly may be used in the transponders 100 and 200 of Figures 1A to 2F. The temperature sensor assembly 400 obtains a temperature measurement indicative of the temperature of the idler roller 1. In this embodiment, the temperature measurement is indicative of the temperature of the bearing 130 of the idler roller 1. Moreover, the temperature sensor assembly 400 senses the temperature of the of idler roller shaft 150 as an indication of the bearing 130.

[0147] To improve the accuracy of this temperature measurement, the temperature sensor assembly 400 comprises a biasing mechanism 402 for biasing a temperature sensor 403 (in the form of a temperature probe) into contact with the idler roller 1 to measure the temperature of the idler roller. In this embodiment, the biasing mechanism 402 biases the temperature probe 403 into contact with the idler roller shaft 150, and takes the form of a spring.

[0148] The temperature sensor assembly 400 comprises a sensor holder 401 for receiving the temperature probe 403, and the spring 402 is engageable with the sensor holder to urge the sensor holder towards the idler roller 1, in this case the idler roller shaft 150. The temperature sensor assembly 400 also has a base 410 engageable with the spring 402, wherein the spring is located between the sensor holder 401 and the base 410. The sensor holder 401 has a land or flange 415 and the base 410 has a land or flange 420 for securing the spring 402 between the sensor holder and the base.

[0149] The temperature sensor assembly 400 further comprises a housing 405 for receiving the sensor holder 401 and spring 402. In this embodiment, the housing 405 comprises a cylindrical sleeve. This enables the sensor holder 401 and temperature probe 403 to slidingly move within the sleeve 405 towards the idler roller 1 from the base 410.

[0150] As noted above, the temperature sensor assembly 400 is used in both the transponder 100 of Figures 1A and 1 B, as well as the transponder 200 of Figures 2A to 2F. In the case of the transponder 100, the temperature sensor assembly 400 is located on the transponder body 110 such that the temperature probe 403 extends through an opening in the collar 119 and biased by the spring 402 into contact with the idler roller bearing 130. Where used in the transponder 200, the temperature sensor assembly 400 is located in the protruding portion 216 of the first shell portion 210 adjacent the idlerroller shaft 150, so that the temperature probe 403 extends from the protruding portion 216 and presses firmly against the idler roller shaft.

[0151] Referring to Figures 5A and 5B, a sensor assembly 500 according to a further embodiment of the invention is illustrated, where the sensor assembly may be used in the transponders 100 and 200 of Figures 1A to 2F. The sensor assembly 500 may either be an acoustic sensor assembly, a vibration sensor assembly or both. The sensor assembly 500 is configured to be an ultra-low powered sensor to minimise battery consumption. The sensor assembly 500 comprises a sensor for generating an electric signal in response to an acoustic or vibrational force and a spectral analyser 505 for processing the electric signal when the processor is in a low power mode. In this embodiment, the sensor is the combined acoustic and vibration sensor 218 shown in Figure 2C.

[0152] The spectral analyser 505 comprises an amplifier 510 for amplifying the electric signal from the sensor 218. There is also a filter bank 520 which breaks the electric signal (representative of the incoming acoustic I vibrational signal) into various diagnostic bands. The diagnostic bands each yields certain diagnostic significance. The filter bank 520 also removes noise from the electric signal after it passes through the amplifier 510.

[0153] The special analyser 505 also comprises one or more filters in the form of band filters 521 , 522 and 523 for converting the electric signal into discrete bands. The spectral analyser further comprises one or more sample and hold circuits 531 , 532 and 533 for processing the electric signal. The filters 521 , 522 and 523 are connected to a corresponding sample and hold circuit of the one or more sample and hold circuits 531, 532 and 533.

[0154] The spectral analyser 500 has been implemented using ultra-low power operational amplifiers for the signal processing blocks. However, the band-filters 521, 522 and 523 could also be implemented digitally, but this approach is not preferred as it would draw more energy, making the transponder 200 increase its energy consumption. In contrast, using ultra-low power operational amplifiers implementing the filters 531, 532 and 533, preferably formed in a bank, in the analog domain greatly extends the battery life of the transponder 200, as the microprocessor can be put unto low-power (sleep)mode whilst the spectral analyser 550, especially the filters 531, 532 and 533, continuously processes the acoustic and / or vibrational signal.

[0155] The combined acoustic and vibration sensor 218 used to detect vibrational or acoustic information is preferably a piezoelectric crystal. However, other similar transducers such as piezoelectric films and electret inserts also could be used. The acoustic / vibrational sensor 218 is mounted onto the wall of the protruding portion 216, as best shown in Figure 2C, enabling a small electrical signal to be generated (typically 10mV - 100mV depending on wall thickness and acoustic energy). The electrical signal is then amplified by an operational amplifier 510. The amplified signal (now several hundred millivolts in amplitude) is fed into a filter in the form of a band-pass filter 520 to remove unwanted out-of-band noise. The band-limited signal is then fed into the bank of the filters 521 , 522 and 523 which shape the spectrum into the bands 541 , 542 and 543, respectively, as shown in in Figure 5B. By selecting an appropriate Q (quality factor) for the filter bank 521, 522 and 523 a near linear phase delay can be achieved 551, 552, 553, as best shown in Figure 5B, which is advantageous for signal analysis and reconstruction. The sample-and-hold circuits 531, 532 and 533 catch or capture transient events from the bands 541, 542, 543 that may not be immediately present when the microprocessor of the transponder 200 drops out of sleep mode and samples its sensors 111, 218 and 400.

[0156] The number of band filters 521, 522 and 523 may vary, and a larger number of band filters (and hence larger number of frequency bands can be used than the three bands selected). However, three bands were chosen based on the various potential sources of conveyor idler roller related noise and vibration -see Table 1 below. The output of the sample and hold circuits 531, 532 and 533 feed into the microprocessor of the transponder 200 for subsequent transmission to the monitoring system.Table 1 : Potential Sources of conveyor roll noise and vibration

[0157] The above transponders 100 and 200 can be included in a monitoring system, as described in WO 2021 / 026606 A1, the disclosure of which has been incorporated by reference in its entirety. Accordingly, a detailed description of the system will not be provided. In summary, the monitoring system comprises a plurality of sensor assemblies 100, 200 mounted to a corresponding plurality of idler rollers 1. The microcontroller of each sensor assembly 100, 200 is configured to broadcast detected or measured sensor data from its various sensors as described above to a secondary wireless communication device that is a communications hub or local network. This hub then sends the sensor data to a diagnostic processing system executing diagnostic software. The secondary wireless communications device thus acts as a data concentrator or aggregator. There may be a plurality of these hubs, located at regular intervals along the length of the conveyor belt system, and can be spaced anywhere from several metres to several kilometres, if required. In this case, the hubs are connected to different sensor assemblies 100, 200 belong to different idler rollers 1. To assist avoid multipath destructive interference from multiple signals, in a further embodiment a diversity-based hub can be employed. This hub would include two separate antennae, which are selectively used based on signal strength. That is, the antenna having the strongest signal strength would be selected and used by the hub to receive and transmit data.

[0158] Alternatively, in other embodiments of the monitoring system, the individual transceivers of each sensor assembly 100, 200 broadcasts the sensor data, which is directly received from the diagnostic system wirelessly.

[0159] The above described transponders 100 and 200 and monitoring system can also be incorporated into a belt conveyor system, as described in WO 2021 / 026606 A1. As such, a detailed description of the belt conveyor system will not be provided. In summary, the belt conveyor comprising a plurality of idler rollers, a plurality of sensor assemblies or telemetry-enabled seal assemblies according to the above described embodiments of the invention and the monitoring system described above, wherein there is a plurality of receivers in communication with the central processing unit, each connected to different sensor assemblies or telemetry-enabled seal assemblies located in different idler rollers.

[0160] While the sensor assemblies 100, 200 have been described as being in the form of a transponder in the above embodiments, it will be appreciated that the sensor assembly can be embodied in other forms, such as a telemetry labyrinth seal unit thatincorporates the labyrinth seal components in the context of modifying pre-existing labyrinth seal to include the sensor assembly. Such a telemetry labyrinth seal unit may be provided where the unit is manufactured to incorporate the sensor assembly, instead of retrofitting to a pre-existing labyrinth seal.

[0161] It will further be appreciated that any of the features in the preferred embodiments of the invention can be combined together and are not necessarily applied in isolation from each other. For example, the different configurations for the transponder 100, 200 described in relation to Figures 1A to 2F may be used with different sensor assemblies in the same monitoring system for a belt conveyor system. In addition, different sensor assemblies may have different combinations of sensors to monitor different parameters or characteristics of the idler rollers at different locations along the belt conveyor. Similar combinations of two or more features from the above described embodiments or preferred forms of the invention can be readily made by one skilled in the art.

[0162] From the above description of the preferred embodiments of the invention, it can be seen that the sensor assembly can be easily fitted and removed from an idler roller, as well as providing accurate measurements of a wide range of parameters or characteristics relating to an idler roller at regular intervals without requiring human involvement. Moreover, the sensor assembly is preferably designed to be incorporated into the modified bearing labyrinth seal where parameters like temperature, vibrations and / or idler roller rotational speed are monitored and wirelessly communicated to a remote receiver (or transceiver) that can be located some metres to several kilometres away. Conveyor data may then be concentrated in an operations centre or remotely hosted. The conveyor data is then analysed to determine the likely failure timing so that a work-order may be scheduled, generated or sent to maintenance staff. As each conveyor roller has two bearings it would be preferable to include two sensor assemblies in each roller, preferably in the form of modified labyrinth seal telemetry units.

[0163] The invention also supports the retrofitting of the sensor assembly into an existing conveyor roller assembly, as well as being part of a brand-new conveyor roller during manufacture. Under certain circumstances, e.g. where battery life is paramount, the sensor assembly may have a simple transmitter which has been programmed broadcast the detected parameter data (generally corresponding to the conveyor roller status) every hour or so.

[0164] Another advantage of the invention is that detected or measured parameter data from the conveyor rollers can be processed in real-time or off-line, depending on the nature and complexity of the failure point prediction algorithms employed by the processor in analysing the detected parameter data.

[0165] By providing a sensor assembly that can be readily mounted and removed from an idler roller, the invention confers the advantages of accurate detection and / or measurement of various operational and other parameters of the idler roller and time saving, since the ability to communicate remotely with the sensors avoids the need for manual detection or measurement of each idler roller. This saving in time and labour also results in significant efficiencies in monitoring the belt conveyor system while reducing or eliminating any potential downtime and safety risks involved with manual measurement. Moreover, the invention permits more accurate measurements to be made and a greater range of measurements to be made simultaneously, in contrast to the prior art where measuring different parameters require different sensors operated by workers. Furthermore, the invention can be readily implemented to existing idler rollers and belt conveyor systems as described above. In all these respects, the invention represents a practical and commercially significant improvement over the prior art

Claims

Claims1. A sensor assembly for an idler roller in a belt conveyor system, comprising: a body for fitting to a shaft of the idler roller, the body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; and a processor in communication with the one or more sensors and the wireless communication device; and a protruding portion for housing the one or more sensors; wherein the one or more sensors transmit the detected parameter data to the processor; the processer causes the detected parameter data to be transmitted by the wireless communication device; and the protruding portion extends from the body such that the protruding portion is spaced apart from and adjacent to the idler roller such that the one or more sensors are able to detect the one or more parameters of the idler roller.

2. The sensor assembly of claim 1, wherein the protruding portion is adjacent to an end of the idler roller and / or the protruding portion extends towards the end of the idler roller.

3. The sensor assembly of claim 1 or 2, wherein the body comprises a first shell portion and a second shell portion, wherein the protruding portion is integrally formed with or connected to at least one of the first body and second shell portions.

4. The sensor assembly of any one of claims 1 to 3, wherein the end of the idler roller comprises an end face of a roll of the idler roller.

5. The sensor assembly of any one of claims 1 to 4, wherein at least one of the one or more sensors comprises a rotation counter for measuring the rotations of the bearing of the idler roller and the sensor assembly comprises a first set of one or more magnets for mounting the body to a frame of the idler roller and / or the shaft of the idler roller, wherein the first set of one or more magnets are mounted to an exterior surface of the body.

6. The sensor assembly of claim 5, wherein at least one of the one or more sensors comprises a rotation counter for measuring the rotations of the bearing of the idler roller and a second set of one or more magnets is mountable to an end face of the idler roller, wherein movement of the second set of one or more magnets is detected by the rotation counter in the protruding portion; and wherein a cover is mounted to the idler roller to protect the second set of one or more magnets.

7. A temperature sensor assembly for an idler roller in a belt conveyor system, comprising: a temperature sensor for measuring the temperature of the idler roller: and a biasing mechanism for biasing the temperature sensor into contact with a shaft of the idler roller or a bearing of the idler roller.

8. The temperature sensor assembly of claim 7, comprising a sensor holder for receiving the temperature sensor and the biasing mechanism is engageable with the sensor holder to urge the sensor holder towards the idler roller.

9. The temperature sensor assembly of claim 7 or 8, comprising a base engageable with the biasing mechanism, wherein the biasing mechanism comprises a spring located between the sensor holder and the base.

10. The temperature sensor assembly of any one of claims 7 to 9, comprising a housing for receiving the sensor holder and biasing mechanism, wherein the sensor holder and temperature sensor slidingly move within the housing.

11. An acoustic sensor assembly or a vibration sensor assembly for an idler roller in a belt conveyor system, comprising: a sensor for generating an electric signal in response to an acoustic or vibrational force; and a spectral analyser for processing the electric signal when the processor is in a low power mode.

12. The sensor assembly of claim 11 , wherein the spectral analyser comprises one or more sample and hold circuits for processing the electric signal and / or one or more filters for converting the electric signal into discrete bands, wherein the output of each filter is fed to one of the sample and hold circuits.

13. The sensor assembly of claim 11 or 12, wherein the spectral analyser comprises an amplifier for amplifying the electric signal from the signal generator and a filter bank for breaking or dividing the electric signal into various diagnostic bands, wherein the filter bank removes noise from the electric signal after it passes through the amplifier.

14. A sensor assembly for an idler roller in a belt conveyor system, comprising: a body for fitting to a shaft of the idler roller, the body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; and a processor in communication with the one or more sensors and the wireless communication device; wherein the one or more sensors transmit the detected parameter data to the processor; the processer causes the detected parameter data to be transmitted by the wireless communication device; and at least one of the one or more sensors comprises at least one of the temperature sensor assembly of any one of claims 7 to 10 for measuring the temperature of a bearing of the idler roller; the vibration sensor assembly of any one of claims 11 to 13 for measuring vibrations experienced by the idler roller and the acoustic sensor assembly of any one of claims 11 to 13 for measuring acoustic data relating to the idler roller.

15. A sensor assembly for an idler roller in a belt conveyor system, comprising: a body for fitting to a shaft of the idler roller, the body having: one or more sensors for detecting one or more parameters of the idler roller; a wireless communication device; and a processor in communication with the one or more sensors and the wireless communication device; and a shaft for engaging a shaft of the idler roller, wherein the shaft is connected to the body; wherein the one or more sensors transmit the detected parameter data to the processor; andthe processer causes the detected parameter data to be transmitted by the wireless communication device.

16. The sensor assembly of claim 15, wherein the shaft comprises a collar, the collar being configured to engage a tool for installing or removing the sensor assembly.

17. The sensor assembly of claim 15 or 16, comprising: a cover engageable with the body for protecting the one or more sensors, the wireless communication device and the processor; and a base engageable with the cover for enclosing the body, wherein the shaft is connected to the base; wherein a protective material comprising a polymeric resin or equivalent material is injected into the space between the body and cover to protect the one or more sensors, the wireless communication device and the processor; and wherein the one or more sensors, wireless communication device and processor are encapsulated or embedded in the protective material.

18. A tool for installing or removing the sensor assembly any one of claims 15 to 17 to and from an idler roller in a belt conveyor system, comprising: a tool body having a bore for receiving the sensor assembly; a clamping mechanism for clamping the seal assembly; and an actuator for moving the tool body into and out of a shaft of the idler roller for positioning the sensor assembly into engagement with the idler roller or removing the sensor assembly from engagement with the idler roller.

19. The tool of claim 18, wherein the clamping mechanism comprises one or more clamping elements for engaging the body of the sensor assembly, wherein the one or more clamping elements are arranged around the circumference of the tool body and comprise movable fasteners; and wherein the tool body has one or more openings in communication with bore such that the one or more clamping elements extend through the openings into the bore to engage the body of the sensor assembly.

20. The tool of claim 18 or 19, wherein the actuator comprises a stop to limit movement of the tool body in the shaft of the idler roller, wherein the stop comprises a flange or plate at one end of the actuator.

Images