Wireless drain plug

ES3078596T3Undetermined Publication Date: 2026-09-15AKTV8 LLC (100 00)
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Patent Information

Application Number
ES2023705734T
Authority / Receiving Office
ES · ES
Patent Type
Patents
Current Assignee / Owner
Priority Date
2023-01-13
Filing Date
2023-01-14
Publication Date
2026-09-15
Estimated Expiration
2043-01-14

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Patent Text Reader

Abstract

A drain plug for a vehicle component includes: a plug body with a stem portion configured to plug a corresponding hole in the vehicle component, and a sensor module. The sensor module includes a sensor and a wireless transmitter configured to transmit data on the readings of at least one sensor. The sensor includes at least one of the following: a temperature sensor, a pressure sensor, and an accelerometer. A system for the wireless monitoring of a vehicle component includes: a plug body with a stem portion configured to plug a corresponding hole in the vehicle component, and a sensor module with at least one sensor and a wireless transmitter configured to transmit data on the readings of at least one sensor. The system also includes a receiver located in the vehicle and configured to receive data from the wireless transmitter.
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Description

Wireless drain plug Background 1. Field of the invention This disclosure relates generally to the detection of one or more physical characteristics on a motor vehicle. More specifically, this disclosure relates to a device and system for adding detection capabilities and wireless data communication related to the detected characteristics. 2. Description of the previous technique Many different vehicles have hubcaps, transmissions, and differentials that contain oil or other lubricant. Monitoring the lubricant temperature within these components can alert you to elevated temperatures and prevent breakdowns, vehicle downtime, and costly roadside repairs. These components also commonly include bearings, where acceleration monitoring can detect bearing wear or failure before a catastrophic failure occurs, allowing vehicle operators to perform maintenance on the failing bearing before it becomes a major roadside problem. Transmissions and differentials typically have housings made of cast aluminum or steel, which are not easily modified to add sensors. These components commonly have drain plugs for draining the lubricant.Wiring harnesses are also difficult to route and secure to wheel ends and axles that are bouncing along the road over bumps and may be exposed to debris buildup, such as mud, snow, ice, etc. Adding a wired sensor to these devices is not easy. Commercial vehicle fleets are particularly motivated to monitor vehicle systems so that preventative maintenance can identify problems before they become roadside failures that can be substantially more costly than scheduled maintenance. As an example, US patent 2007 / 193348 A1 relates to tire pressure gauges that can remain mounted on the tire / wheel assembly during wheel operation and also include a transmitter for remotely signaling information regarding the pressure inside the tire. Similarly, GB patent 2575656 A, considered prior art, discloses an oil plug for installation on an oil-filled device and for monitoring the device's operating conditions using one or more sensors. Additionally, WO patent 2015 / 143431 A2 describes a lubrication / bleed fitting for a wellhead or valve assembly that allows sealing at both low and high pressures. Summary This disclosure provides a drain plug for a vehicle component. The drain plug includes: a plug body having a stem portion configured to plug a corresponding hole in the vehicle component; a sensor module including at least one sensor and a wireless transmitter configured to transmit data relating to a reading from the at least one sensor; a tubular sleeve disposed in the plug body and defining an external thread on an outer surface thereof; and a sensor cap assembly configured to screw onto the external thread of the tubular sleeve and to secure the sensor module thereto. The at least one sensor includes at least one of the following: a temperature sensor, a pressure sensor, and / or an accelerometer. This disclosure also provides a drain plug for a vehicle component. The drain plug includes: a sensor module comprising at least one sensor and a wireless transmitter configured to transmit data relating to a reading from the at least one sensor. The drain plug also includes a plug body having a stem portion configured to plug a corresponding hole in the vehicle component. The stem portion defines a blind hole in fluid communication with the sensor module, and the stem portion is sealed to fluidly isolate the sensor module and an internal space of the vehicle component. The drain plug also includes a tubular sleeve disposed in the blind hole, extending outward from it and defining an external thread on an outer surface of the sleeve outside the blind hole.The drain plug also includes a sensor cap assembly configured to screw onto the external thread of the tubular sleeve and to secure the sensor module to it. This disclosure also provides a system for wirelessly monitoring a vehicle component. The system includes a drain plug comprising: a plug body having a stem portion configured to plug a corresponding hole in the vehicle component, and a sensor module having at least one sensor and a wireless transmitter configured to transmit data relating to a reading from the at least one sensor. The system also includes a receiver located in the vehicle and configured to receive data from the wireless transmitter. The at least one sensor includes at least one of the following: a temperature sensor, a pressure sensor, and an accelerometer. Brief description of the drawings Additional details, features, and advantages of the invention's designs are derived from the following description of exemplary embodiments with reference to the associated drawings. FIG. 1 shows an exploded cross-section perspective view of a first sensor plug of the present disclosure; FIG. 2 shows a cross-sectional perspective view of a second sensor plug of the present disclosure; FIG.3A shows a perspective view of a sensor drain plug body of FIG.2; FIG.3B shows a cross-sectional perspective view of the body of the second sensor plug of FIG. 2; FIG. 4 shows a cross-sectional view of a truck tire hub including a sensor plug of the present disclosure; FIG. 5 shows a block diagram of a system for remote monitoring of signals from a sensor plug, according to one aspect of this disclosure; and FIG. 6 shows a diagram of a system for remote monitoring of signals from sensor plugs mounted on each of a wheel hub and a differential of a semi-trailer, according to an aspect of this disclosure. Detailed description With reference to the drawings, the present invention will be described in detail in view of the following embodiments. This disclosure provides a sensor-equipped drain plug with a microchip and wireless communication capabilities, enabling the simple replacement of a drain plug with a smart sensor array that can monitor temperature, pressure, and acceleration. Onboard microprocessing allows for fault detection and alerts to operators / fleets before a major failure occurs. The sensor module is battery-powered and easy to retrofit to vehicles. It can communicate with mobile devices or a separate control unit. This disclosure provides a sensor-equipped drain plug with a microchip and wireless communication capabilities that allows for the simple replacement of a drain plug with an intelligent sensor suite capable of monitoring temperature, pressure, and acceleration. This suite uses onboard microprocessing to detect faults and alert operators / fleets before a major failure occurs. The drain plug described herein includes a battery-powered sensor module with wireless communication capabilities, eliminating the need for a wiring harness, and is easy to retrofit to vehicles. The drain plug can communicate with mobile devices or a standalone control unit. A commercial vehicle system is also provided, which includes sensor-equipped drain plugs on hubcaps and differentials that communicate with a pneumatic control module.The pneumatic control module can illuminate its diagnostic LED to alert the driver if an imminent failure is occurring and send data via telemetry to the fleet command center to alert them of the problem. The drain plug described in this disclosure can detect one or more temperature, pressure, and acceleration parameters. This drain plug can be used with a system that can generate an alert based on the temperature exceeding a threshold value for a predetermined period of time, which may indicate an overheating condition. Additionally or alternatively, this drain plug can be used with a system that can generate an alert based on the pressure being above a predetermined high-pressure threshold, indicative of a high-pressure condition, or below a predetermined low-pressure threshold, indicative of a low-pressure condition. Additionally or alternatively, this drain plug can be used with a system that can generate an alert based on acceleration, indicative of a fault or warning condition.These acceleration-based conditions can include, for example, an acceleration pattern indicative of a bearing failure, or a high-impulse acceleration indicative of an impact, such as hitting a curb. Acceleration-based conditions can also include other acceleration-based patterns that may indicate an imbalance, such as a flat spot or an unbalanced tire. Fleet managers and operators can use the collected data in any instance where failures result in downtime and costly roadside repairs. As shown in FIG. 1, a first sensor plug 20 includes a first plug body 22, a first sensor module 24, and a first plug cap 26. The first sensor plug 20 is configured to screw into an opening, such as a drain hole, instead of a standard drain plug on a vehicle component, such as a transmission, differential, or wheel hub. The first plug body 22 includes a first stem portion 30 having a rod-like shape extending between a first distal end 32 and a first proximal end 34. The first stem portion 30 is configured to plug a corresponding orifice, such as a fluid drain hole, in the vehicle component. The first stem portion 30 defines a first external thread 36 for mating with an internal thread in the orifice of the vehicle component (not shown in FIG. 1). The first stem portion 30 also defines a through-hole 38 extending coaxially through it from the first distal end 32 to the first proximal end 34.The first stem portion 30 also defines a first housing 40 that intersects the through-hole 38, which has a larger diameter than the through-hole 38 and extends from the first proximal end 34 a short distance into the first stem portion 30. For example, the first housing 40 may have a depth of 5 mm to 10 mm. A first tubular seal 28, which may be made of rubber or another resilient material, is disposed in the first housing 40 and provides a seal with a lower surface of the first sensor module 24, while allowing fluid communication between a small area of ​​the lower surface of the first sensor module 24 and an internal space of the vehicle component, through the through-hole 38.This fluid communication can allow the first sensor module 24 to measure the temperature and / or pressure within the internal space of the vehicle component, while also blocking fluid from exiting the internal space of the vehicle component. The first plug body 22 also includes a first peripheral tube 42 extending annulus around the first stem portion 30 adjacent to the first proximal end 34. The first peripheral tube 42 defines a plurality of first flat faces 43 at regular intervals thereabouts for engagement with a tool, such as a socket wrench, for installing or removing the first plug body 22 from the vehicle component. A first flange portion 44 extends annulus around the first stem portion 30 between the first external thread 36 and the first proximal end 34. The first flange portion 44 connects the first peripheral tube 42 to the first stem portion 30. The first stem portion 30 of the first plug body 22 also defines a first annular groove 46 on an outer surface thereof between the first flange portion 44 and the first proximal end 34.A first O-ring 48 is disposed in the first annular groove 46 to provide a watertight seal with the first plug cap 26. The first sensor module 24 is arranged adjacent to the first proximal end 34 of the first plug body 22 and is configured to measure one or more physical characteristics of the vehicle component, such as temperature, pressure, and / or acceleration. The first sensor module 24 includes a first printed circuit board assembly (PCBA) 60 having a substrate such as a printed circuit board, a first processor 62, a first wireless communication interface 64, and one or more sensors 66, 68, 69. The sensors 66, 68, 69 may include an accelerometer 66, a temperature sensor 68, and / or a pressure sensor 69. However, the first sensor module 24 may include a different combination of sensors and / or one or more different types of sensors. One or more of the sensors 66, 68, 69 may have direct exposure to an internal space of the vehicle component through the through-hole 38.The first processor 62 may include a microprocessor, microcontroller, and / or other processing circuitry. The first processor 62 may perform certain signal processing from one or more sensors 66, 68, 69. For example, the first processor 62 may compare one or more acceleration signals from accelerometer 66 in order to determine whether the one or more acceleration signals are indicative of bearing wear or an imbalance condition in a rotating assembly within the vehicle component. The first sensor module 24 also includes a battery 70, such as a coin cell battery. One or more pins 72 are attached to a lower surface of the first PCBA 60 and configured to mate with the first proximal end 34 of the first plug body 22. The pins 72 may be made of a helical coil of wire. The pins 72 may provide some vibration isolation between them. Alternatively or additionally, the pins 72 may be configured to allow the transmission of vibration and / or heat between them. A metal housing 74, such as stainless steel, secures the battery 70 to the first PCBA 60. A retaining ring 76 extends annulus around the housing 74 and the first PCBA 60 to fix the housing 74 to the first PCBA 60. A clamping clip 78, which may be made of a bent piece of sheet metal, holds the first sensor module 24 in position over the first proximal end 34 of the first plug body 22. The first cap 26 is disposed on one end of the first cap body 22, opposite the first stem portion 30, and encloses the first sensor module 24 to protect it from exposure to moisture, dust, or other contaminants. The first cap 26 may be made of a material that is radio-transmissive, such as plastic. The first cap 26 has a cup shape that includes a first tubular wall 80 defining a first internal thread 82 for attachment to the first stem portion 30 of the first cap body 22. The first cap 26 also includes a closed top portion 84 that encloses the cup shape to contain the first sensor module 24. Figures 2 and 3A-3B show a second sensor plug 120 of this disclosure. The second sensor plug 120 may be similar or identical to the first sensor plug 20, except for some differences described herein. As shown in FIG. 2, the second sensor plug 120 includes a second plug body 122, a second sensor module 124, and a second plug cap 126. The second sensor plug 120 is configured to screw into an opening, such as a drain hole, instead of a standard drain plug on a vehicle component, such as a transmission, differential, or wheel hub. The second plug cap 126 may be similar or identical to the first plug cap 26 of the first sensor plug 20. The second plug body 122 includes a second stem portion 130, which has a rod-like shape extending between a second distal end 132 and a second proximal end 134. The second stem portion 130 defines a second external thread 136 for mating with an internal thread in the bore of the vehicle component (not shown in FIG. 2). The second stem portion 130 also defines a recess 138 in the second distal end 132 that receives and retains a magnet 139. The magnet 139 can be used to retain metal parts, such as chips, that are ejected during operation of the vehicle component. The second stem portion 130 also defines a blind hole 140 that extends from the second proximal end 134 and partially through and coaxially with the second stem portion 130.The blind hole 140 can provide thermal communication between the second sensor module 124, or a temperature sensor attached to it, and a fluid within the internal space of the vehicle component, while preventing fluid communication between them. Therefore, the blind hole 140 can provide improved detection accuracy of the fluid within the internal space of the vehicle component, while also preventing the second sensor module 124 from coming into direct contact with the fluid within the internal space of the vehicle component. The second plug body 122 also includes a second peripheral tube 142 that extends annulus around the second stem portion 130 adjacent to the second proximal end 134. The second peripheral tube 142 defines a plurality of second flat faces 143 at regular intervals therearound it for engagement with a tool, such as a socket wrench, for installing or removing the second plug body 122 from the vehicle component. A second flange portion 144 extends annulus around the second stem portion 130 between the second external thread 136 and the second proximal end 134. The second flange portion 144 connects the second peripheral tube 142 to the second stem portion 130. A tubular sleeve 146 is disposed in the blind hole 140 and extends outward from it, beyond the second proximal end 134. The tubular sleeve 146 may be press-fitted within the blind hole. Alternatively or additionally, the tubular sleeve 146 may be attached to the second stem portion 130 by one or more different means, such as a threaded connection, welding, and / or adhesive. The tubular sleeve 146 defines a third external thread 148 on an outer surface of the sleeve outside the blind hole 140. The tubular sleeve 146 with the third external thread 148 may match an external thread of a Schrader valve. A sensor cap assembly 170 is configured to screw onto the third external thread 148 of the tubular sleeve 146 and to secure the second sensor module 124 to it. When the third external thread 148 is a Schrader-type thread, matching the thread of a standard Schrader valve, a single standard part can be used for both the sensor cap assembly 170 and a tire pressure monitoring device configured to screw onto a Schrader valve on a tire valve stem. This can provide economies of scale, making the sensor cap assembly 170 readily and inexpensively available. Alternatively, the tubular sleeve 146 can be used with the first sensor plug 20. For example, the tubular sleeve 146 can be partially positioned within the through-hole 38 and protrude from it to connect the sensor cap assembly 170. The sensor cap assembly 170 includes a second tubular portion 172 that surrounds and threads onto the third external thread 148 of the tubular sleeve 146. A semi-closed top 174 covers one end of the second tubular portion 172. The sensor cap assembly 170 also includes a third tubular portion 176 that defines a through passage 177 providing fluid communication to the blind hole 140 through the tubular sleeve 146. A first O-ring 179 extends between a lower surface of the semi-closed top 174 and an upper edge of the tubular sleeve 146 to provide a liquid-tight seal between them. The sensor cap assembly 170 also includes a radial protrusion 178 extending radially outward from the second tubular portion 172. A sensor cap cover 190 is disposed around the sensor cap assembly 170 and molded around the radial protrusion 178.A second O-ring 182 is disposed between the sensor cap cover 190 and the second proximal end 134 of the second stem portion 130 to provide a liquid-tight seal between them. The first O-ring 179 and / or the second O-ring 182 may be made of rubber or another resilient material. The sensor cap cover 190 defines a fourth external thread 192 and a second annular groove 194 on an outer surface thereof, which retains a second O-ring 195 to provide a watertight seal with the second plug cap 126. The sensor cap cover 190 also defines a second housing 196 on an upper surface thereof to receive the second sensor module 124. A second tubular gasket 180, which may be made of rubber or another resilient material, is disposed in the second housing 196 and provides a seal between a lower surface of the second sensor module 124 and an upper surface of the semi-enclosed top 174 of the sensor cap assembly 170, while allowing fluid communication between a small area of ​​the lower surface of the second sensor module 124 and an internal space of the blind hole 140. This fluid communication may allow the second sensor module 124 to more accurately measure a temperature within the internal space of the vehicle component, while also blocking fluid from escaping from the internal space of the vehicle component. The second sensor module 124 may be similar or identical to the first sensor module 24. The second sensor module 124 includes a second PCBA 160. Because the second sensor plug 120 does not include any fluid connection to the vehicle component, the second sensor plug 120 may not include any pressure sensor. Figure 4 shows a component 12 of a vehicle 10 with a sensor plug 20, 120 of this disclosure. More specifically, the component 12 shown in Figure 4 is a wheel hub of a truck tire. Figure 5 shows a block diagram of a system 200 for the remote monitoring of signals from a sensor plug 20, 120. The system includes one or more sensor plugs 20, 120, which may include one or more of the first sensor plug 20 and / or one or more of the second sensor plug 120. As shown, the sensor plug 20, 120 includes a first processor 62 operatively connected to a temperature sensor 68, a pressure sensor 69, and an accelerometer 66 to receive signals from them relating to corresponding detected parameters. The sensor plug 20, 120 includes a first wireless communication interface 64, which may include a radio that is operatively connected to the processor to communicate data relating to the detected values ​​from one or more of the sensors 66, 68, 69.The first wireless communications interface 64 may include a digital communications interface, such as a Bluetooth, Wi-Fi, ZigBee or other short or medium range communications interface. The sensor plug 20, 120 includes a first processor 62 coupled to a first storage memory 210. The first storage memory 210 stores instructions, such as program code for execution by the first processor 62, in a first instruction store 212. The first storage memory 210 also includes a first data store 214 to hold data to be used by the first processor 62. The first data store 214 can record, for example, parameter values ​​measured by one or more of the sensors 66, 68, 69, stored diagnostic trouble codes (DTCs), and / or the result of one or more functions calculated by the first processor 62. System 200 also includes a receiver located in the vehicle and configured to receive data from the first wireless communication interface 64 of one or more of the sensor plugs 20, 120. For example, as shown in FIG. 6, System 200 includes a communication module 220 configured to receive data from sensor plug 20, 120. The communication module 220 may be integrated within a pneumatic controller, which may be located on or near a vehicle axle 10. The communication module includes a second wireless communication interface 222 configured to communicate with one or more of the sensor plugs 20, 120, and a third wireless communication interface 226 configured to communicate with one or more different devices within the vehicle 10.One or both of the second wireless communication interface 222 and / or the third wireless communication interface 226 may include a digital communication interface, such as a Bluetooth, Wi-Fi, ZigBee, or other short- or medium-range communication interface. The communication module 220 also includes a first controller 224, which may include a microprocessor or microcontroller and is programmed to control the storage and transfer of data between the second wireless communication interface 222 and the third wireless communication interface 226. The system 200 also includes a bridge 230 located in the vehicle and configured to collect information from one or more of the sensor plugs 20, 120 located throughout the vehicle 10 and to issue a warning or fault message based on data detected by the sensor plugs 20, 120. In some embodiments, and as shown in FIG.5, the bridge 230 is operatively connected to a user interface 238, such as a warning light or a warning message on a display screen, to notify a vehicle operator 10 of an error condition detected by one or more of the sensor plugs 20, 120. The bridge 230 includes a fourth wireless communications interface 232, such as a Bluetooth, Wi-Fi, ZigBee or other short- or medium-range communications interface, to receive information from one or more of the communications modules 220. Alternatively or additionally, the fourth wireless communications interface 232 can receive data directly from one or more of the sensor plugs 20, 120, without an intermediate communications module 220. Bridge 230 also includes a telemetry interface 236, such as a Long Term Evolution (LTE) cellular data modem, to communicate vehicle information 10 to a remote receiver. The telemetry interface 236 may use other communication types, such as other cellular data standards, vehicle-to-everything (V2X), point-to-point, satellite-based communications, etc. Bridge 230 also includes a second controller 234, which may include a microprocessor or a microcontroller and is programmed to control the storage and transfer of data between the fourth wireless communication interface 232 and the telemetry interface 236 and / or to control the transmission of messages by the user interface 238 based on data from sensor plugs 20, 120. The system 200 also includes a server 250, which can store and / or process data from a fleet of vehicles, using telemetry data from the bridge 230 in vehicle 10, and communicating via one or more networks 240. The one or more networks 240 may include, for example, a cellular data network, the Internet, and one or more wide area and / or local area networks. The server 250 includes a second processor 260 coupled to a second storage memory 262. The second storage memory 262 includes a second instruction store 264 that stores instructions, such as program code, for execution by the second processor 260. The second storage memory 262 also includes a second data store 266 to hold data for use by the second processor 260.The second data storage 266 may include a database configured to record, for example, parameter values ​​measured by one or more sensors 66, 68, 69 and / or the results of functions calculated by the first processor 62 in the sensor plugs 20, 120. Additionally or alternatively, the second data storage 266 of the server 250 may store message data, such as records of warning or fault messages associated with vehicle components 12 that are monitored by the sensor plugs 20, 120. For example, the second data storage 266 may store a list of error messages, which may identify a specific date, time, component 12, detected value, etc. Figure 6 shows a diagram of a system for remotely monitoring signals from sensor plugs 20, 120 mounted on each of a wheel hub and a differential of a vehicle 10. Figure 6 shows the vehicle 10 as a semi-trailer / truck that includes the sensor plugs 20, 120 in communication with a bridge 230 via a communications module 220. Figure 6 also shows the vehicle 10 that includes the user interface 238 in the cab for broadcasting a fault condition to an operator of the vehicle 10. The system, methods, and / or processes described above, and their stages, may be implemented in hardware, software, or any combination of hardware and software suitable for a particular application. The hardware may include a general-purpose computer and / or a dedicated computing device or a specific computing device, or a particular aspect or component of a specific computing device. The processes may be implemented in one or more microprocessors, microcontrollers, embedded microcontrollers, programmable digital signal processors, or other programmable devices, along with internal and / or external memory. The processes may also, or alternatively, be incorporated into an application-specific integrated circuit, a programmable gate array, programmable matrix logic, or any other device or combination of devices that can be configured to process electronic signals.It will also be appreciated that one or more of the processes can be carried out as computer executable code capable of being executed on a machine-readable medium. Executable computer code can be created using a structured programming language such as C, an object-oriented programming language such as C++, or any other high-level or low-level programming language (including assembly languages, hardware description languages, and database programming languages ​​and technologies) that can be stored, compiled, or interpreted for execution on one of the aforementioned devices, as well as heterogeneous combinations of processors, processor architectures, or combinations of different hardware and software, or any other machine capable of executing program instructions. Therefore, in one respect, each of the methods described above and combinations thereof can be incorporated into executable computer code that, when executed on one or more computing devices, performs the corresponding execution steps.In another aspect, the methods can be incorporated into systems that perform their steps, and can be distributed among devices in various ways, or all functionality can be integrated into a dedicated, standalone device or other hardware. Furthermore, the means of performing the steps associated with the processes described above can include any of the hardware and / or software described above. It is intended that all such permutations and combinations fall within the scope of this disclosure.

Claims

1. A drain plug (20, 120) for a vehicle component (10), comprising: a plug body (22, 122) defining an orifice (38, 140) and having a stem portion (30, 130) configured to plug a corresponding orifice in the vehicle component (10); a sensor module (24, 124) including at least one sensor (66, 68, 69) and a wireless transmitter (64) configured to transmit data relating to a reading from the at least one sensor; wherein the at least one sensor includes at least one of: a temperature sensor, a pressure sensor, or an accelerometer; characterized in that the drain plug (20, 120) further comprises: a tubular sleeve (146) disposed in the orifice within the plug body, the tubular sleeve (146) defining an external thread (148) on an outer surface thereof; and a sensor cap assembly (170) configured to screw onto the external thread (148) of the tubular sleeve (146) and to secure the sensor module (24,124) to the same.

2. The drain plug of claim 1, wherein the external thread (148) of the tubular sleeve (146) engages an external thread of a Schrader valve.

3. The drain plug of claim 1, wherein the stem portion (30) defines a through-hole (38) extending therethrough to provide fluid communication between the sensor module (24) and an internal space of the vehicle component (10).

4. The drain plug of claim 1, wherein the stem portion (130) defines a blind hole (140) in fluid communication with the sensor module (124), and the stem portion (130) is sealed to fluidly isolate the sensor module (124) and an internal space of the vehicle component (10).

5. The drain plug of claim 1, wherein the at least one sensor (66, 68, 69) includes a temperature sensor.

6. The drain plug of claim 1, wherein the at least one sensor (66, 68,69) includes a pressure sensor.

7. The drain plug of claim 1, wherein the sensor module (24, 124) further includes a processor (62) configured to process a signal from at least one sensor (66, 68, 69).

8. The drain plug of claim 7, wherein the at least one sensor (66, 68, 69) includes an accelerometer, and wherein the processor (62) is configured to process an acceleration signal from the accelerometer to determine at least one of: a condition indicative of bearing wear or a condition indicative of an imbalance in the vehicle component (10).

9. The drain plug of claim 1, further comprising a cap (26, 126) configured to cover an end of the plug body opposite the stem portion and to enclose the sensor module, and wherein the cap is made of a material that is transmissive to radio waves.

10. The drain plug of claim 4,wherein the tubular sleeve (146) is disposed in the blind hole (140) and extends outward from it, defining the external thread (148) on its outer surface outside the blind hole (140).

11. A system for wirelessly monitoring a vehicle component (10), comprising: the drain plug of claim 9; and a receiver located in the vehicle (10) and configured to receive data from the wireless transmitter (64).

12. The system of claim 11, wherein the receiver is integrated within a pneumatic controller located on or near an axle of the vehicle (10).

13. The system of claim 11, further comprising a bridge (230) located in the vehicle and configured to collect information from the drain plug (20, 120) and to issue a warning or fault message based on data relating to the reading of at least one sensor (66, 68, 69).

14. The system of claim 13,further comprising a user interface (238) located in the vehicle (10) and in functional communication with the bridge (230), the user interface being configured to display a warning or message based on data relating to the reading of at least one sensor (66, 68, 69).

15. The system of claim 13, further comprising a server (250) located remotely with respect to the vehicle (10) and in functional communication with the bridge (230), the server (250) being configured to receive and store data relating to the reading of at least one sensor (66, 68, 69).