CA2226829C - Early warning device for tire rims and hub assemblies - Google Patents
Early warning device for tire rims and hub assemblies Download PDFInfo
- Publication number
- CA2226829C CA2226829C CA 2226829 CA2226829A CA2226829C CA 2226829 C CA2226829 C CA 2226829C CA 2226829 CA2226829 CA 2226829 CA 2226829 A CA2226829 A CA 2226829A CA 2226829 C CA2226829 C CA 2226829C
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- Canada
- Prior art keywords
- trailer
- cab
- axle
- fault
- axles
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
- B60C23/20—Devices for measuring or signalling tyre temperature only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
- B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
- B60C23/005—Devices specially adapted for special wheel arrangements
- B60C23/009—Devices specially adapted for special wheel arrangements having wheels on a trailer
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Regulating Braking Force (AREA)
- Valves And Accessory Devices For Braking Systems (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
The present invention relates to an apparatus to provide a monitoring device fordetecting problems associated with the wheels of trucks and trailers. The apparatus comprises one or more individual axle spindle sensors, a programmable micro processor for receiving and processing the sensor signals to detect an alarm condition and alarm means to alert the driver of a problem with one or more of the wheels.
Description
TITLE: E,ARLY WARNING DEVICE FOR TIRE RIMS AND HUB
~'~SSEMBLIES
5 ~ BACKGROUr~D OF THE ~NVENTION
1rhis invention relates to apparatus to detect a problem prior to the random detachment of the tire rims and/or complete or partial wheel hub assemblie~i of vehicle~
particularily heavy highway transport vehicles. In particular the present invention 10 provides a networked microcontroller based system that monitors and records all operating axle faults for multi axle vehicles including a cab and trailer(~i) hookup.
Dl SCRIPTIO~ OF THE PRIOR ART
l'he safety of heavy highway transport vehicles has been a seriou~i problem with ~m increase in the number of accidents and even fatalitie~i caused by tire rirns or complete or partial wheel hub assemblies becoming detached from heavy vehicles particulaily trucks or trailers and hitting passenger vehicles. The regulatory 20 authorities have instituted spot checks to identify vehicles that are not being properly maintained and public concern has increased as a high percentage of the vehiclesin~spected have defects of one type or another. Even those vehicles that are properly maintained, can experience random detachment of tire rims or complete wheel hub as~iemblies if an oil seal breaks.
The main reason for the detachment of tire rims and wheel hub as~ielnhlie~
is due to the overheating of wheel bearings due to a lack of lubricant and/or imprope bearing load. ~nocking caused by improper bearing pre-load, a cracked bearing ca.~ie.
Ioose wheel nuts. broken studs and cracked rims is also an indication of possible 30 imminent detachment. There is a need for a system to effectively detect the~ie problellls so that they can be corrected before the tire rim or wheel hub a~isembly become~de tached .
' CA 02226829 1998-02-11 SUMMARY OF THE INVENTION
It is an object of the invention to provide an early warning system to detect a problem prior to the random detachment of the tire rims and/or wheel hub 5 ~ assemblies of vehicles, particularily heavy highway transport vehicles.
It is a further object of the invention to provide an early warning syste that utilizes a networked microcontroller based system that monitors and records all operating axle faults for a multi axle vehicle including a cab and trailer(s) hookup.
It is a further object of the invention to provide an early warning system 10 that gives an audio and visual signal when a problem is detected.
It is a further object of the invention to provide an early warning systelll that continuou,ly monitors the effects of heat, noise, vibration and knocking on wheel bearing and brakes.
l'hus in accordance with the present invention there is provided a monitoring device for detecting problems associated with the wheels of multi axle ve~hicles comprising one or more individual axle spindle sensors, a programmable IlliCI O
processor for receiving and processing the sensor signals to detect an alarm condition and alarm means to alert the driver of a problem with one or more of the wheels. In the 2() preferred embodiment the sensors detect heat, noise, vibration or knocking associated with the wheels and brakes. Typically the sensors are located on the axle within the wheel hub and brake pads. The processor monitors changes in the heat, noise and vibration of the wheel bearins, wheel assembly and brakes detected by the sensors and der~ermines when an alarm condition exists.
In accordance with another embodiment the present invention provide~ a nelworked microcontroller based system for monitoring and recording operating axle i'aults for a multi axle vehicle where each of the axles on the vehicle has wheel~ and brclkes at both ends of the axles. The system includes sensors capable of monitorill_ 3() he;lt, noise, vibration and shocks associated with the axles, brakes and wheels mounled on each axle. C)ne or more sensor CPUs are connected to the sensors monitoring the ax]es and wheels and brakes. One or more fault recording CPUs are connected to the sensor CPUs. One of the fault recording CPUs has a keypad and display for systelll initialization and when a fault is detected, a fault warning means alerts the operator ol' 35 the vehicle.
' CA 02226829 1998-02-11 In accordance with another embodiment, the present invention provide~ a nel:worked microcontroller based system for monitoring and recording operating axle i~aults for vehicles including a cab and one or more trailers, where said cab has at lea~t two cab axles with wheels and brakes at both ends of said cab axles and said trailer has 5 one or more trailer axles with wheels and brakes at both ends of said trailer axles. The system comprises a series of sensors capable of monitoring heat, noise, vibration and - shocks associated with said axles, brakes and wheels mounted on each cab axle and each trailer axle, one or more cab sensor CPUs connected to the sensors monitorill(l the cab axles and wheels and brakes, one or more trailer sensor CPUs connected to the 1() sensors monitoring the trailer axles and wheels and brakes, a cab fault recording CPU
connected to said cab sensor CPUs, a trailer fault recording CPU connected to said trailer sensor CPUs, said cab fault recording CPU having a keypad and display for system initialization and fault warning and means to permit the cab fault recording CPU
anll trailer faull. recording CPU to communicate with each other. The means to pern1it the 15 cab fault recording CPU and trailer fault recording CPU to communicate with each othe preferably consists of a multiplex bus.
In another embodiment of the invention a communication system fol-tractor trailers i.s provided comprising a cab CPU incorporating a transmittel1receiver and 2() a trailer CPU incorporating a transmitter receiver wherein the cab CPU and the trailer CF'U communicate with each other on a multiplex bus. The multiplex bus uses a circuit on the standarcl seven pin connection preferably a lree turn signal lamp wire for transmitting and receiving data. The cab CPU is programmable to control or monitor one or more auxilary functions on the trailer. These auxilary functions are unlimited and 25 include for example in-cab warning lights in response to a signal from the trailer to the cab if there is an antilocking brake system (ABS) malfunction on the trailel-. In addilion the system can be programmed so that the operator can control from the cab: lift axle operation, operate rear door locks, operate emergency stop warning lights on the trailel-.
op~-rate tail gates, hoppers, valves and chutes. operate back up lights and horn on thc 3() trailer. The operator can also from the cab monitor: drive shaft overheating~ brake adjustment on the trailer, brake pad wear, trailer rel'ridgeration units, load shift or weigl1t of the trailer and the like.
Further features of the invention will be described or will become apparel1t 3 5 in the course of the following detailed description.
BE~IEF DESCR IPTION OF THE DRAWINGS
In order that the invention may be more clearly understood, the preferred embodiment thereof will now be described in detail by way of example, with 5 ref'erence to the accompanying drawings, in which:
Figure 1 is a schematic illustration of an early warning system according to the present mvention;
I 0 Figure 2 is a schematic illustration of another embodiment of an early warning syste according to the present invention;
Figure 3 is a block diagram of a preferred embodiment of the fault recording CPUs and sensor CPUs comprising a networked microprocessor system according to the presellt I S invention;
Figure 4 is a lateral plan view in partial cross section of a typical axle for a dual wheel assembly having a sensor mounted thereon in accordance with the present inventiom 20 Figure SA is schematic view of a sensor in accordance with the present invention;
Figure SB is a side plan view of a sensor in accordance with the present invention attached to a block which is to welded to an axle;
25 Figure 6 is a block diagram for a sensor module CPU illustrated in Figure 3;
Figure 7 is a block diagram for a fault recording CPU illustrated in Figure 3;
Figure 8 is a flow chart of the general system control t'rom cab during data samplillg:
3() Figure 9 is a flow chart of the cab fault recording CPU:
Figure 10 is a flow chart of the process current system mode module of Figure 9;
35 Fgure 11 is a f]ow chart for the process verify hookup module of Figure 9;
Figure 12 is a ilow chart of the CAB FRC start data module of Figure 9;
Figure 13 is a ilow chart of the send start command module of Figure 9;
5 ' Figure 14 is a rnain flowchart for FRCs;
- Fipure 15 is a flow chart of the process for Initialization of all axles module of Figul-e l ~:
Figure 16 is a llow chart of the process data sample of all axles module of Figure 14:
Figure 17 is a ilow chart of the process all axle faults module of Figure 14;
Figure 18 is a -flow chart of the process to check knock on every axle module of Figul-e 14;
Figure 19 is a ~FIow chart of the process to check bearing temperature module of Figul-e 14;
Figure 20 is a ilow chart to check brake differential module of Figure 14;
Figure 21 is a ilow chart of a process wheel fault log of Figure 14;
Figure 22 is a flow chart of the sensor module flow diagram;
25 Figure 23 is a flow chart of the Initialize All I/O and Control Variables module of Fi~lul-e 22;
Figure 24 is a flow chart of the Initialize Command module of Figure 22;
30 Figure 25 is a ilow chart of the Process Sensor Signal Command Module of Figure ~:
Figure 26 is a i-low chart of the Sensor Sample Module of Figure 22;
Figure 27 is a Flow chart of the Process Left/Right Knock Channels Module of Figul-e 35 22; and Figure 28 is a ~low chart of the Auto Gain Module of Figure 22;
DE~TAILED D]_SCRIPTION OF THE PREFERRED EMBODIMENT
The early warning system of the present invention is designed to detect L
problem which may result in tire rims or complete or partial wheel hub assemblies - becoming detached from a vehicle, such as a truck or trailer, and hitting passenger vehicles. The nnain reason for the detachment of tire rims or wheel hub assemblies is d~le to the overheating of wheel bearings due to a lack of lubricant and/or improper bea~ g 1() load. KnockingJ, vibration and noise caused by improper bearing pre-load, cracked bearing case, loose wheel nuts, broken studs or cracked rims can also be an indicatioll ol' imminent detachment.
C)ne embodiment of the early warning system of the present invention t'o use on the axles of a vehicle, particularily heavy highway vehicles, is schematically illustrated in Figure 1. The early warning system, generally indicated at 1, in its simplest form comprise, one or more individual sensors 2 which are capable of monitoring lleal.
noise, vibration or knocking associated with potential problems which may result in tire rims and or complete wheel hub assemblies becoming detached from the vehicle. The 2() sensors 2 are located on each individual axle 3 and 4. Wheels S are located at the end of each of the axles. The sensors' 2 location is typically determined by the sensitivity desired: the closer to the source of the heat, noise, vibration or knocking the greatel- tl~e sensitivity. In the preferred embodiment the sensors are located on the axle within tlle wheel hub. The sensors 2 are connected by individual output lines 6 to a programlnal~le micro processor 7. The micro processor 7 receives the information signal or data ~-om the sellsors 2. This information is in the form of voltage and resistance change. The miclo processor 7 is programmable so that when a change in voltage and resistance reaclle~
specified parameters the micro processor 7 determines an alarm condition is presellt an(l that data is sent to the alarm means 8. The micro processor 7 and/or alarm means 8 c~m 3() either be separate pieces of equipment, may be combined in one device. Alternai\~el~ the alarm means 8 may be an already existing component on the vehicle that can be programmed to deal with the data from the sensors 2 and or the micro processol- 7. Tlle alarm means 8 preferably comprises an audio visual micro processing annunciator ~
which will alert the operator of the vehicle by alarm means 10 of the alarm condition: i.e.
overheating, malfunctioning bearings, and or excessive knocks or vibration caused t-~
broken studs, loose nuts, cracked rims and or improper bearing pre-load. The alarm I () may be in the form of an LED display, lights, buzzer, or other visual or audio display device or combination of same.
~I reset button 11 is preferably provided in association with the alarm means 8 that will enable the operator to confirm the alarm condition.
I'he system is powered as an auxiliary on the fuse box 12 and draws frolll the vehicle's electrical power supply system. A back up system can be provided !iUCIl as a rechargeable battery etc.
1() E,y utilizing a digital programmable microprocessor 7 the system can be capable of storing in memory the data from the sensors 2 for inspection purposes to help determine the cause of detachment. Further a digital key pad can be provided to enahle the operator to isolate specific sensors and/or perform other functions if required.
The sensors 2 are located on the individual axles 3, 4 as noted above. Each sensor 2 has its own output line(s) 6 which can be plugged in to the microprocessing unit 7. These output lines 6 preferabbly use an eight wire harness. The sensors 2 convel-t the conditions being monitored, heat, noise, vibration and knocking, into resistance alld 2() voltage which is sent to the microprocessor 7. The microprocessor 7 is programmed so that a change in voltage and resistance meeting prescribed parameters over a defined period of time is deemed an alarm condition. This information is converted to data thL-t i~
sent to the annunciator 9 which then alerts the operator by both visual and audio mealls 10 that a specific sensor(s) is detecting an alarm condition. The data is sent trom micrprocessor 7 to the annunciator 9 by a four wire harness 13. The operator uses thc reset button(s) l l to confirm the sensor is detecting an alarm condition. The operatol- C.
then pull over and make appropriate repairs or request assistance to avoid the loss ol' a tire rim or wheel hub assembly 5. Where axle 3 reprsentL. the axles on the cab of a tr~lcl and axle 4 represents the axles on a trailer, provision can be made to connect the oulpll~
3() lines from sensors on a pup trailer or piggy back through connection 14.
~nother embodiment of the invention comprising a networked microcontroller based system that monitors and records all operating axle t'aults for a multi axle vehicle and in particular a cab and trailer hookup is schematically illustrated in Figure 2 and 3 Figure 2 illustrates the front axle 20 and rear axles 21, 22 of a vehicle cab and axles 23, 24, 25 and 26 of a trailer. Wheel assemblies 27 are located at the ends ot' each of the axles 20 to 26. The wheel assemblies 27 can be either single wheels as typically foundi on the front axle 20 or dual wheels as typically found on axles 21 ~o '6.
Drive shaft 28 powers the rear axles 21, 22 of the cab. Sensors 29, capable of monitoring heat, noise, vibration, shocks and calibration or adjustment associated witl 5 ' the axles, brakes and wheels, are located adjacent each individual wheel assembly 27.
The sensors 29 on each axle are connected by individual output lines 30 to a sellsol - module CPU (SMC) 31 located in proximity to each of the axles. The cab and trailer are each also equipped with a fault recording CPU (FRC), 32 and 33 respectively~ that communicates with the sensor module CPU 31 for each axle of the cab or trailer l() respectivelly. T he FRC 32 in the cab has an additional keypad and display used l'or system initialization and to provide a fault warning system 34 to alert the driver ol any axle problems. Sensors 35 are also shown on drive shaft 28 to monitor heat, noise and vibration changes that could indicate drive shaft problems. These sensors 35 areconnected by individual output lines 36 to a sensor module CPU 37 that communicate~
15 with the fault recording CPU 32.
In the preferred embodiment the FRC's, 32 and 33, communicate with each other on a multiplex bus (MXBUS) 38 that uses a wire connected to one ol the pirls on the standard seven pin connector between the cab and trailer for transmittill_ 2() and receiving clata. This is accomplished by pulsing a high frequency carrier on the selected wire. I)ual frequencies are used, one f'or receive. one for transmit to allow l'ol 1 duplex communication on the single wire. In the preferred embodiment a turn signal lamp wire is selected. The frequency carriers are low voltage, and are detectable even it the signal lamp is pulsing and will not interfere with the turn signals. The MXBUS is a 25 three conducto;r bus, one for signal, one for signal com. one for power. These conductors can be found on all truck harnesses that provide the center power pin l'or a aul~ilary circuit or power for the ABS brakes. For older equipment, the trailer will havc lo be equipped with a standard lead-acid battery to power the fault recording CPU. Tlli~
battery could be charged by having the running lights activated for a period ol time 3() ~ s best illustrated in Figure 3. all FRC s. 32 and 33, communicate witl their own local SMC's 31 via a sensor module bus (SMBUS) 39. The SMBUS is preferably a four conductor bus utilizing the RS-485 interl'ace standard. This interface standard implements a balanced multi-point transmit/receive communication line used in 35 a party line configuration. This allows the cab FRC 32 to connect to the SMC on axle 20, the SMC on axle 20 to the SMC on axle 21 and the SMC on axle 21 to the SMC on axle 22. The trailer FRC 33 connects to the SMC on axle 23, the SMC on axle 23 to tlle SMC on axle 24, the SMC on axle 24 to the SMC on axle 25 and so on to the last trailel-axle. This fealure reduces the amount of wiring harness along the bottom of the cab or trailer.
S
If a pup trailer is hooked up to trailer a similar arrangement is utilized. Thc sensors on each axle are connected by individual output lines to a sensor module CPU
(SMC) 31 located in proximity to each of the axles on the pup trailer. The pup traile also equipped with a fault recording CPU (FRC) 40 that communicates with the sensol l0 module CPU for each axle of the pup trailer. The pup trailer FRC 40 communicale~ with Fl~C's in the cab 32 and on the trailer 33. As noted in the preferred embodiment all the F~C's communicate with each other on a multiplex bus (MXBUS) 38 that uses a ireeturn signal lamp wire for transmitting and receiving data.
A typical axle having a sensor mounted thereon in accordance with thc present invention is illustrated in Figures 4. One end of an axle 41 is illustrated partly in cross section. The other end of the axle would typically be the mirror image of the end illustrated. A spindle 42 projects beyond the end of the axle 41. A hub 43 enca!ies the spindle 42 and inner bearings 44 and outer bearings 45. The cavity 46 between lhe hul 43 and spindle 42 is half filled with oil and sealed by inner seals 47 and an outer seal 4~.
A grit cover 4'3 is located on the axle behind the inner seal 47. A brake support spiclel 50 is welded to the axle 41 and supports brake shoes 51. The end 52 of the spindle 4 is threaded to permit attachment of the tire assembly by means of hub lock nuts 53. 54 ancl lock washer 55. A typical dual tire assembly, generally indicated at 58, consists of a l~ai of tires (not shown) mounted on rims either in the form of bud rims 59, 60 (as shown ) Or on a spoke hub assembly not shown. The bud rims 59, 60 are attached by wheel nul~
and studs 62 to hub 43. Hub cap 63 encloses the end of the spindle 42. A brake dl-64 is also connected to hub 43 by studs 62 and the brake drum 64 encases the hr. ke shoes 51. A dust shield 65 is connected to the brake support spider 50. A brake mini (f~
is connected to the brake cam shaft 67.
As noted above the main reason for the detachment of rims 59,60 or h.ll-~
43 is due to the overheating of wheel bearings 45 and 44 due to a lack of lubricant and/or improper bearing load. Accordingly the present invention utilizes sensors 29 that are capable of monitoring the temperature of the wheel assembly on the end of any axle and comparing it to the temperature of the other wheels on the same axle and othel axles as well as a pre-selected maximum permitted temperature. The sensors 29 are al~o capable of monitoring noise, vibration and knocking associated with the each axle ancl wheel hub assembly caused by improper bearing pre-load, a cracked bearing case. looie wheel nuts, broken studs and cracked rims which are also indications of possible5 imminent detachment.
- In Figs. SA and 5B the preferred configuration of sensors 29 is illustrated.
Each sensor 29 consists of a thermally conductive housing 70 into which is mounted a temperature transducer 71 to monitor the temperature of the wheel bearings 44, 45 alld ;
1() vibration transducer 72 for monitoring noise, vibration and knocking. In the prel'erl-e(l embodiment, ~utput lines 73 from each of the temperature transducer 71 and vibratioll transducer 72 e xit the housing through outlet 74. An additional wire 75 is looped willlin the outlet 74 to permit connection to a second remote temperature transducer 76. This second temperature transducer 76 can be encased within a thermally conductive l S housing 76A, sealed with epoxy to prevent moisture and/or ambient air from interfe~ g with the opera~tion of the sensor and mounted adjacent the brake shoes (as showll in Figure 4) to monitor any changes in the temperature of the brakes which may be indicative of a problem. The housing 70 is enclosed by panel 77 and sealed with epoxy to prevent moisture and/or ambient air from interfering with the operation of the sell~ol.
2() The housing 70 and panel 77 are constructed of thermally conductive materials so th.lt any temperature changes caused by overheating of the wheel bearings can be deteclecl by temperature transducer 71. The sensor 29 is secured by screws 78A to a blocl~ 78 which is adapted to be welded to the axle 41 adjacent the wheel assembly. The temperature of the bearings is transmitted through the axle and accordingly the proximity of the sensor 29 and block 78 to the wheel bearings 44, 45 the more reliahle the readings. The housing 70 and panel 77 are pret'erably fabricated from stainless steel (303 SS) to resist corrosion. The block 78 is preferably welded to the axle 41 betwee the hub 43 ancl the brake support spider SO as shown on Figure 4 l he sensors 29 are connected by individual output lines 73. 75 lo a ~en~o module CPU 31 located in proximity to each of the axles. The sensol- module CPUs al e preferably attarhed to the frame of the cab and trailer(s). As shown in Figure 3 the c.lh.
trailer and pup trailer if any are each also equipped with its own fault recording CPU
(FRC)32, 33 and 40 respectively, that communicates with the sensor module CPU for each axle of the cab or trailer or pup trailer. The FRC 32 in the cab has an additional keypad and display 79 used for system initialization and to provide a fault warning ' CA 02226829 1998-02-11 system to alert the driver of any axle problems. Each FRC 32, 33 and 40 i~ al~o equil~pe(l with an interrogation interface 80, 81 and 82 respectively for connection to a hand held terminal or lab top computer. This feature allows interrogation of isolated trailer~ a~ ell as cab/trailer hookups.
s l'he FRC 32 in the cab has a real-time clock 83 for logging date and ~hlle of occurring faults. During initialization of a cab/trailer hookup, the cab FRC 32 will transfer the current date and time to the FRC 33 for the trailer and the FRC 40 fol- thc pup trailer if any. When the cab FRC 32 receives faults from the trailer FRCs 33. 4(). it will respond b~y sending back the date and time for stol-age in the trailer FRC EEPro X4. This eliminates the need for a battery backed-up read time clock on trailer FRC
33,40. The cab FRC 32, maintains battery power to the real time clock flom the cah battery to maintain the time. The time and date can be reset and verified by the drivel-prior to initializing all trailers in the system should the cab battery be disconnected or l'ail l .~ m servlce.
E ach Sensor Module CPU (SMC) 31 will monitor two temperature ~en~ol s 71, 76 (bearin~" brake) and one vibration sensor 72 for each wheel on the axle. Il any wheel generates a suspected fault, the fault code is transmitted by the SMC 31 lo the FRC 32, 33 or 40 for further processing. The FRC is then responsible for verifying ~he fault is true by comparing to all other axles on the trailer/cab. If the fault is valid it i~
then hard recorded in the EEProm 84 and passed on to the cab FRC 32 through a multiplexed connection (MXBUS) 38 for driver warning.
1'he FRC's 32, 33 and 40 can communicate with each other by a variety ol' known means. The FRC's could be connected by wire or co-axial cable however authorities are discouraging additional wire connections between the cab and trailel- all~l restricting wire or cable to the current seven prong connection. Radio receivers all~l transmitters or cellular connections could be utilized however a reliable, secul-e intel-l'.lce 3() without the po.sibility of outside interference or disruption is required.
As shown in Figs. 3 and 7, in the preferred embodiment the FRC?~ 32. 33 and 40, communicate with each other on a multiplexed connection (MXBUS) 38 (see Figs. 3 and 7) chat uses a circuit in the standard seven pin (J560 pin). As noted above in the preferred embodiment a free turn signal lamp wire is utilized for transmitting and receiving data. This is accomplished by pulsing a high frequency carrier on the turll signal wire. Dual frequencies are used, one for receive through receiver 90, and one t'or transmit by transmitter 91 to allow for full duplex communication on the single wire.
These frequency carriers are low voltage, and are detectable even if the signal lamp is pulsing and will not interfere with the turn signals. The MXBUS is a three conductol-S bus, one for signal, one for signal com, one for power. These conductors, can be foul1cl on all truck harnesses that provide the center pin for power to the ABS brakes. For older equipment, the trailer will have to be equipped with a standard lead-acid battery to power the fault recording CPU, this battery could be charged by having the running lights activated for a period of time.
]3y utilizing a multiplexing connection between the cab and trailer~ it i~
possible to incorporate a number of programmable auxiliary features into the syslem. I
accordance with U.S. regulations after March 1, 2001 all tractors must have in-cab warning lights and trailers must be capable of sending a signal to the tractor if there i~; a 15 antilocking braLke system (ABS) malfunction on the trailer. Currently the warning li'gllt i~
located on the trailer. The present invention provides a very effective solution to this requirement. In addition the system can be programmed so that the operator can COlltlOI
from the cab: .Lift axle operation, operate rear door locks, operate emergency stop warning lights on the trailer, operate tail gates, hoppers, valves and chutes, operale ba-li 20 up lights and horn on the trailer. The operator can also from the cab monitor: drive shat't overheating, brake adjustment on the trailer, brake pad wear, trailer reflidgeratioll UllitS.
Ioad shift or weight of the trailer and the like.
All FRC's communicate with their own local SMC's via a sensor module 25 bus (SMBUS) 39. The SMBUS 39 is preferably a four conductor bus utilizing the RS-485 interface standard. The SMBUS includes transmitter 85 and receiver 86 at the FRC
and corresponding transmitter 92 and receiver 93 at the SMC. This interface stalldal (I
implement~ a balanced multi-point transmit/receive communication line ~lsed in a l~art~
line configuralion. This allows the FRC 32 to connect to SMC 31 on axle 20. SMC 3 l 30 on axle 20 to ',MC 31 on axle 21 and so on to the last axle. This feature reduce~ tlle amount of wir.ing harness along the bottom of the cab or trailer.
As shown in Figs. 3 and 7, all the FRC's 32, 33 and 40 communicate with their corresponding Interrogate Terminal 80, 81 and 82 via an interrogate bus (ITGBUS ) 35 87. This bus preferably uses a standard three conductor RS232 communication protocol.
which is availaLble on all standard computer equipment. Again the ITGBUS include~, a transmitter 88 and receiver 89. An extra power plug will be provided by the Interl-o~ e Terminal for connection to a trailer FRC which may be isolated with no existing pOWel.
~s shown in Figure 6, each sensor module CPU 31 has a microconlrolle 5 '- 94 to measure all sensors 29 on its axle and to communicate with the corresponding FRC 32, 33 or 40. A PIC16C74 microcontroller has been used in the preferred embodiment. E,ach SMC 31 is equipped with a silicon hardware ID code 95 tor module identification. This identification number can be transl'erred to and logged in the FRC
EEProm 84 during every initialization.
I() E,ach SMC 31 preferably has a hardware jumper 96 to identify its axle number to the ]FRC. This jumper is preferably set prior to shipping, and SMC's can he identified by a label (ie Axle 1) for installation. An optional EEProm 97 can beconnected to the SMC 31 for programmable identification and calibration parameters.
The SMC 31 program design (Figs. 22 to 28) is broken into two basic areas: Sensor Hardware/Fault Algorithm Design and Software Communication Protocol Design.
2() The Sensor Hardware/Fault Algorithm Design is programmed as follows:
Temperature of the bearings and brakes is measured by sensors 29 preferably using a semi conductor sensor for the bearings and a platinum resistallce probe (RTD) for the brakes. The RTD probe has an operating range of -200~ C to 800~C with an excellent temperature stability of less than 1% over the range- 50~C to 800~C. The platinum RTD probe has a large resistance change output for its operati~
range, 80 ohm, at-50~C to 375 ohms at 800~C with good linearity over that range. By applying a lma reference current to the probe, a voltage output of 60mv to 375 IllV 0\'el the -50~C to 8()0~C range can be achieved. This signal can then be amplified and3() sampled by the coresponding SMC 31 analog/digital (A/D) input: 98 for left bearillg temperature, 9'3 for right bearing temperature~ lO0 for left brake temperature and l O l l'or r i~ht brake temperature. Gain is used to adjust the span of temperature measurement t'or the bearing or brakes. This will also determine the temperature resolution of the A/D
converter within microcontroller 94. The A/D converter in the prefen-ed microcontroller has 256 steps, providing the following resolutions:
E,earing Temperature: 0 to 250 Deg C approx: ldeg/step ' CA 02226829 1998-02-11 Brake Temperature: 0 to 800 Deg C approx: 3 deg/step Ambient tempcrature (TAmbient) is monitored by the FRC 32, 33 and 40 by temperat~ e transducer 102 and then transferred to all sensor module CPU's. A temperature fault will 5 '' exist under the following conditions, where TBearing is the temperature of the bearillg as measured by temperature transducer 71 (Figure 5), TAmbient is the ambient air- tennperature measured by the temperature transducer 102 at the FRC, TBearing Maximum is a pre-selected temperature difference indicative of overheating, TBrakeLet'~
is l:he temperature of the left brake on an axle measured by the second temperatul-c 1() transducer 76 (Figure 6), TBrakeRight is the temperature of the right brake on tllc ~ame axle measured by temperature transducer 76 and TBrake Maximum is a pre-selecteclternperature difference indicative of overheating:
l. TBearing - TAmbient > TBearing Maximum = fault 2. TBrakeLeft-TBrakeRight>TBrakeMaximum = fault 15 ln the preferreci embodiment a TBearing Maximum of 190~F has been selected toinclicate an alarm condition. With respect to the brake temperature, a 30% differential bel~ween the lel't and right brake on an axle is preferably used to indicate an alar m condition .
~,'ibration Knocking vibration on the wheel/axle joint can be measul-ed hy seIlsor 29 using a vibration transducer 72, preferrably a crystal transducer. asschematically illustrated in Figure. S. The transducer 72 produces a voltage proportional to the amplitucle and frequency of the vibration being generated by the wheel/axle joint.
The Xtal signa] (amplitude and time as plotted on the X-Y axis) can be amplified. rectil'ie(l and filtered to leave the low frequency enveloped. The microcontroller is programme(l ~o deltermine a Vibration Fault Condition under the following conditions:
Knock: The Sensor Module CPU 31 can monitor the rectified/filteled signal on it~ A/D
input, 102A for left wheel vibration transducer and and 103 for the right wheel vit r.lti 3() transducer, for a fixed amount of time (ie 10 wheel revolutions) and determine if thel-e i~
a cyclic pattern to the knock by measuring the time duration between pulses. The w l~eel lock signal will help to determine if there is a phase relationship of knock to wheel position regardless of wheel speed. If a phase-locked pattern is detected a fault code i~
sent to the FRC. The FRC would then check other wheels to see if the same fault is occurring on other axles (which would be indicative of road noise). The FRC would monitor the condition for a fixed time interval and if the fault is still valid it is then passed on to the cab FRC to alert driver of possible trouble.
Grind: A continuous high amplitude signal, regardless of wheel position may indicate a 5 ~ bearing grind, and would be used to generate a fault if it is produced for an extendec~
period of time. This would probably be accompanied with increased bearing temperature.
E~ach SMC communicates on the SMBUS with the FRC as tollows.
. The FRC sends out a 4 byte command structure to the SMC
ie. 1. [Axle ID] --axle id number to select the specified SMC.
2. [Command] -- requested action of SMC -- see table below.
3. [Parameter] -- additional command parameter 4. [:] - the end of command character Command Libra1~:
2 0 ~1 Initialize I -- Identify Fault 2 -- Load New Ambient Temp 3 -- Return Left Bearing Temp 4 -- Return Right Bearing Temp 5 -- Return Left Brake Temp 6 -- Return Right Brake Temp 7 -- Return Left Vibration Amplitude 8 -- Return Right Vibration Amplitude 9 -- Return Left Wheel RPM
~'~SSEMBLIES
5 ~ BACKGROUr~D OF THE ~NVENTION
1rhis invention relates to apparatus to detect a problem prior to the random detachment of the tire rims and/or complete or partial wheel hub assemblie~i of vehicle~
particularily heavy highway transport vehicles. In particular the present invention 10 provides a networked microcontroller based system that monitors and records all operating axle faults for multi axle vehicles including a cab and trailer(~i) hookup.
Dl SCRIPTIO~ OF THE PRIOR ART
l'he safety of heavy highway transport vehicles has been a seriou~i problem with ~m increase in the number of accidents and even fatalitie~i caused by tire rirns or complete or partial wheel hub assemblies becoming detached from heavy vehicles particulaily trucks or trailers and hitting passenger vehicles. The regulatory 20 authorities have instituted spot checks to identify vehicles that are not being properly maintained and public concern has increased as a high percentage of the vehiclesin~spected have defects of one type or another. Even those vehicles that are properly maintained, can experience random detachment of tire rims or complete wheel hub as~iemblies if an oil seal breaks.
The main reason for the detachment of tire rims and wheel hub as~ielnhlie~
is due to the overheating of wheel bearings due to a lack of lubricant and/or imprope bearing load. ~nocking caused by improper bearing pre-load, a cracked bearing ca.~ie.
Ioose wheel nuts. broken studs and cracked rims is also an indication of possible 30 imminent detachment. There is a need for a system to effectively detect the~ie problellls so that they can be corrected before the tire rim or wheel hub a~isembly become~de tached .
' CA 02226829 1998-02-11 SUMMARY OF THE INVENTION
It is an object of the invention to provide an early warning system to detect a problem prior to the random detachment of the tire rims and/or wheel hub 5 ~ assemblies of vehicles, particularily heavy highway transport vehicles.
It is a further object of the invention to provide an early warning syste that utilizes a networked microcontroller based system that monitors and records all operating axle faults for a multi axle vehicle including a cab and trailer(s) hookup.
It is a further object of the invention to provide an early warning system 10 that gives an audio and visual signal when a problem is detected.
It is a further object of the invention to provide an early warning systelll that continuou,ly monitors the effects of heat, noise, vibration and knocking on wheel bearing and brakes.
l'hus in accordance with the present invention there is provided a monitoring device for detecting problems associated with the wheels of multi axle ve~hicles comprising one or more individual axle spindle sensors, a programmable IlliCI O
processor for receiving and processing the sensor signals to detect an alarm condition and alarm means to alert the driver of a problem with one or more of the wheels. In the 2() preferred embodiment the sensors detect heat, noise, vibration or knocking associated with the wheels and brakes. Typically the sensors are located on the axle within the wheel hub and brake pads. The processor monitors changes in the heat, noise and vibration of the wheel bearins, wheel assembly and brakes detected by the sensors and der~ermines when an alarm condition exists.
In accordance with another embodiment the present invention provide~ a nelworked microcontroller based system for monitoring and recording operating axle i'aults for a multi axle vehicle where each of the axles on the vehicle has wheel~ and brclkes at both ends of the axles. The system includes sensors capable of monitorill_ 3() he;lt, noise, vibration and shocks associated with the axles, brakes and wheels mounled on each axle. C)ne or more sensor CPUs are connected to the sensors monitoring the ax]es and wheels and brakes. One or more fault recording CPUs are connected to the sensor CPUs. One of the fault recording CPUs has a keypad and display for systelll initialization and when a fault is detected, a fault warning means alerts the operator ol' 35 the vehicle.
' CA 02226829 1998-02-11 In accordance with another embodiment, the present invention provide~ a nel:worked microcontroller based system for monitoring and recording operating axle i~aults for vehicles including a cab and one or more trailers, where said cab has at lea~t two cab axles with wheels and brakes at both ends of said cab axles and said trailer has 5 one or more trailer axles with wheels and brakes at both ends of said trailer axles. The system comprises a series of sensors capable of monitoring heat, noise, vibration and - shocks associated with said axles, brakes and wheels mounted on each cab axle and each trailer axle, one or more cab sensor CPUs connected to the sensors monitorill(l the cab axles and wheels and brakes, one or more trailer sensor CPUs connected to the 1() sensors monitoring the trailer axles and wheels and brakes, a cab fault recording CPU
connected to said cab sensor CPUs, a trailer fault recording CPU connected to said trailer sensor CPUs, said cab fault recording CPU having a keypad and display for system initialization and fault warning and means to permit the cab fault recording CPU
anll trailer faull. recording CPU to communicate with each other. The means to pern1it the 15 cab fault recording CPU and trailer fault recording CPU to communicate with each othe preferably consists of a multiplex bus.
In another embodiment of the invention a communication system fol-tractor trailers i.s provided comprising a cab CPU incorporating a transmittel1receiver and 2() a trailer CPU incorporating a transmitter receiver wherein the cab CPU and the trailer CF'U communicate with each other on a multiplex bus. The multiplex bus uses a circuit on the standarcl seven pin connection preferably a lree turn signal lamp wire for transmitting and receiving data. The cab CPU is programmable to control or monitor one or more auxilary functions on the trailer. These auxilary functions are unlimited and 25 include for example in-cab warning lights in response to a signal from the trailer to the cab if there is an antilocking brake system (ABS) malfunction on the trailel-. In addilion the system can be programmed so that the operator can control from the cab: lift axle operation, operate rear door locks, operate emergency stop warning lights on the trailel-.
op~-rate tail gates, hoppers, valves and chutes. operate back up lights and horn on thc 3() trailer. The operator can also from the cab monitor: drive shaft overheating~ brake adjustment on the trailer, brake pad wear, trailer rel'ridgeration units, load shift or weigl1t of the trailer and the like.
Further features of the invention will be described or will become apparel1t 3 5 in the course of the following detailed description.
BE~IEF DESCR IPTION OF THE DRAWINGS
In order that the invention may be more clearly understood, the preferred embodiment thereof will now be described in detail by way of example, with 5 ref'erence to the accompanying drawings, in which:
Figure 1 is a schematic illustration of an early warning system according to the present mvention;
I 0 Figure 2 is a schematic illustration of another embodiment of an early warning syste according to the present invention;
Figure 3 is a block diagram of a preferred embodiment of the fault recording CPUs and sensor CPUs comprising a networked microprocessor system according to the presellt I S invention;
Figure 4 is a lateral plan view in partial cross section of a typical axle for a dual wheel assembly having a sensor mounted thereon in accordance with the present inventiom 20 Figure SA is schematic view of a sensor in accordance with the present invention;
Figure SB is a side plan view of a sensor in accordance with the present invention attached to a block which is to welded to an axle;
25 Figure 6 is a block diagram for a sensor module CPU illustrated in Figure 3;
Figure 7 is a block diagram for a fault recording CPU illustrated in Figure 3;
Figure 8 is a flow chart of the general system control t'rom cab during data samplillg:
3() Figure 9 is a flow chart of the cab fault recording CPU:
Figure 10 is a flow chart of the process current system mode module of Figure 9;
35 Fgure 11 is a f]ow chart for the process verify hookup module of Figure 9;
Figure 12 is a ilow chart of the CAB FRC start data module of Figure 9;
Figure 13 is a ilow chart of the send start command module of Figure 9;
5 ' Figure 14 is a rnain flowchart for FRCs;
- Fipure 15 is a flow chart of the process for Initialization of all axles module of Figul-e l ~:
Figure 16 is a llow chart of the process data sample of all axles module of Figure 14:
Figure 17 is a ilow chart of the process all axle faults module of Figure 14;
Figure 18 is a -flow chart of the process to check knock on every axle module of Figul-e 14;
Figure 19 is a ~FIow chart of the process to check bearing temperature module of Figul-e 14;
Figure 20 is a ilow chart to check brake differential module of Figure 14;
Figure 21 is a ilow chart of a process wheel fault log of Figure 14;
Figure 22 is a flow chart of the sensor module flow diagram;
25 Figure 23 is a flow chart of the Initialize All I/O and Control Variables module of Fi~lul-e 22;
Figure 24 is a flow chart of the Initialize Command module of Figure 22;
30 Figure 25 is a ilow chart of the Process Sensor Signal Command Module of Figure ~:
Figure 26 is a i-low chart of the Sensor Sample Module of Figure 22;
Figure 27 is a Flow chart of the Process Left/Right Knock Channels Module of Figul-e 35 22; and Figure 28 is a ~low chart of the Auto Gain Module of Figure 22;
DE~TAILED D]_SCRIPTION OF THE PREFERRED EMBODIMENT
The early warning system of the present invention is designed to detect L
problem which may result in tire rims or complete or partial wheel hub assemblies - becoming detached from a vehicle, such as a truck or trailer, and hitting passenger vehicles. The nnain reason for the detachment of tire rims or wheel hub assemblies is d~le to the overheating of wheel bearings due to a lack of lubricant and/or improper bea~ g 1() load. KnockingJ, vibration and noise caused by improper bearing pre-load, cracked bearing case, loose wheel nuts, broken studs or cracked rims can also be an indicatioll ol' imminent detachment.
C)ne embodiment of the early warning system of the present invention t'o use on the axles of a vehicle, particularily heavy highway vehicles, is schematically illustrated in Figure 1. The early warning system, generally indicated at 1, in its simplest form comprise, one or more individual sensors 2 which are capable of monitoring lleal.
noise, vibration or knocking associated with potential problems which may result in tire rims and or complete wheel hub assemblies becoming detached from the vehicle. The 2() sensors 2 are located on each individual axle 3 and 4. Wheels S are located at the end of each of the axles. The sensors' 2 location is typically determined by the sensitivity desired: the closer to the source of the heat, noise, vibration or knocking the greatel- tl~e sensitivity. In the preferred embodiment the sensors are located on the axle within tlle wheel hub. The sensors 2 are connected by individual output lines 6 to a programlnal~le micro processor 7. The micro processor 7 receives the information signal or data ~-om the sellsors 2. This information is in the form of voltage and resistance change. The miclo processor 7 is programmable so that when a change in voltage and resistance reaclle~
specified parameters the micro processor 7 determines an alarm condition is presellt an(l that data is sent to the alarm means 8. The micro processor 7 and/or alarm means 8 c~m 3() either be separate pieces of equipment, may be combined in one device. Alternai\~el~ the alarm means 8 may be an already existing component on the vehicle that can be programmed to deal with the data from the sensors 2 and or the micro processol- 7. Tlle alarm means 8 preferably comprises an audio visual micro processing annunciator ~
which will alert the operator of the vehicle by alarm means 10 of the alarm condition: i.e.
overheating, malfunctioning bearings, and or excessive knocks or vibration caused t-~
broken studs, loose nuts, cracked rims and or improper bearing pre-load. The alarm I () may be in the form of an LED display, lights, buzzer, or other visual or audio display device or combination of same.
~I reset button 11 is preferably provided in association with the alarm means 8 that will enable the operator to confirm the alarm condition.
I'he system is powered as an auxiliary on the fuse box 12 and draws frolll the vehicle's electrical power supply system. A back up system can be provided !iUCIl as a rechargeable battery etc.
1() E,y utilizing a digital programmable microprocessor 7 the system can be capable of storing in memory the data from the sensors 2 for inspection purposes to help determine the cause of detachment. Further a digital key pad can be provided to enahle the operator to isolate specific sensors and/or perform other functions if required.
The sensors 2 are located on the individual axles 3, 4 as noted above. Each sensor 2 has its own output line(s) 6 which can be plugged in to the microprocessing unit 7. These output lines 6 preferabbly use an eight wire harness. The sensors 2 convel-t the conditions being monitored, heat, noise, vibration and knocking, into resistance alld 2() voltage which is sent to the microprocessor 7. The microprocessor 7 is programmed so that a change in voltage and resistance meeting prescribed parameters over a defined period of time is deemed an alarm condition. This information is converted to data thL-t i~
sent to the annunciator 9 which then alerts the operator by both visual and audio mealls 10 that a specific sensor(s) is detecting an alarm condition. The data is sent trom micrprocessor 7 to the annunciator 9 by a four wire harness 13. The operator uses thc reset button(s) l l to confirm the sensor is detecting an alarm condition. The operatol- C.
then pull over and make appropriate repairs or request assistance to avoid the loss ol' a tire rim or wheel hub assembly 5. Where axle 3 reprsentL. the axles on the cab of a tr~lcl and axle 4 represents the axles on a trailer, provision can be made to connect the oulpll~
3() lines from sensors on a pup trailer or piggy back through connection 14.
~nother embodiment of the invention comprising a networked microcontroller based system that monitors and records all operating axle t'aults for a multi axle vehicle and in particular a cab and trailer hookup is schematically illustrated in Figure 2 and 3 Figure 2 illustrates the front axle 20 and rear axles 21, 22 of a vehicle cab and axles 23, 24, 25 and 26 of a trailer. Wheel assemblies 27 are located at the ends ot' each of the axles 20 to 26. The wheel assemblies 27 can be either single wheels as typically foundi on the front axle 20 or dual wheels as typically found on axles 21 ~o '6.
Drive shaft 28 powers the rear axles 21, 22 of the cab. Sensors 29, capable of monitoring heat, noise, vibration, shocks and calibration or adjustment associated witl 5 ' the axles, brakes and wheels, are located adjacent each individual wheel assembly 27.
The sensors 29 on each axle are connected by individual output lines 30 to a sellsol - module CPU (SMC) 31 located in proximity to each of the axles. The cab and trailer are each also equipped with a fault recording CPU (FRC), 32 and 33 respectively~ that communicates with the sensor module CPU 31 for each axle of the cab or trailer l() respectivelly. T he FRC 32 in the cab has an additional keypad and display used l'or system initialization and to provide a fault warning system 34 to alert the driver ol any axle problems. Sensors 35 are also shown on drive shaft 28 to monitor heat, noise and vibration changes that could indicate drive shaft problems. These sensors 35 areconnected by individual output lines 36 to a sensor module CPU 37 that communicate~
15 with the fault recording CPU 32.
In the preferred embodiment the FRC's, 32 and 33, communicate with each other on a multiplex bus (MXBUS) 38 that uses a wire connected to one ol the pirls on the standard seven pin connector between the cab and trailer for transmittill_ 2() and receiving clata. This is accomplished by pulsing a high frequency carrier on the selected wire. I)ual frequencies are used, one f'or receive. one for transmit to allow l'ol 1 duplex communication on the single wire. In the preferred embodiment a turn signal lamp wire is selected. The frequency carriers are low voltage, and are detectable even it the signal lamp is pulsing and will not interfere with the turn signals. The MXBUS is a 25 three conducto;r bus, one for signal, one for signal com. one for power. These conductors can be found on all truck harnesses that provide the center power pin l'or a aul~ilary circuit or power for the ABS brakes. For older equipment, the trailer will havc lo be equipped with a standard lead-acid battery to power the fault recording CPU. Tlli~
battery could be charged by having the running lights activated for a period ol time 3() ~ s best illustrated in Figure 3. all FRC s. 32 and 33, communicate witl their own local SMC's 31 via a sensor module bus (SMBUS) 39. The SMBUS is preferably a four conductor bus utilizing the RS-485 interl'ace standard. This interface standard implements a balanced multi-point transmit/receive communication line used in 35 a party line configuration. This allows the cab FRC 32 to connect to the SMC on axle 20, the SMC on axle 20 to the SMC on axle 21 and the SMC on axle 21 to the SMC on axle 22. The trailer FRC 33 connects to the SMC on axle 23, the SMC on axle 23 to tlle SMC on axle 24, the SMC on axle 24 to the SMC on axle 25 and so on to the last trailel-axle. This fealure reduces the amount of wiring harness along the bottom of the cab or trailer.
S
If a pup trailer is hooked up to trailer a similar arrangement is utilized. Thc sensors on each axle are connected by individual output lines to a sensor module CPU
(SMC) 31 located in proximity to each of the axles on the pup trailer. The pup traile also equipped with a fault recording CPU (FRC) 40 that communicates with the sensol l0 module CPU for each axle of the pup trailer. The pup trailer FRC 40 communicale~ with Fl~C's in the cab 32 and on the trailer 33. As noted in the preferred embodiment all the F~C's communicate with each other on a multiplex bus (MXBUS) 38 that uses a ireeturn signal lamp wire for transmitting and receiving data.
A typical axle having a sensor mounted thereon in accordance with thc present invention is illustrated in Figures 4. One end of an axle 41 is illustrated partly in cross section. The other end of the axle would typically be the mirror image of the end illustrated. A spindle 42 projects beyond the end of the axle 41. A hub 43 enca!ies the spindle 42 and inner bearings 44 and outer bearings 45. The cavity 46 between lhe hul 43 and spindle 42 is half filled with oil and sealed by inner seals 47 and an outer seal 4~.
A grit cover 4'3 is located on the axle behind the inner seal 47. A brake support spiclel 50 is welded to the axle 41 and supports brake shoes 51. The end 52 of the spindle 4 is threaded to permit attachment of the tire assembly by means of hub lock nuts 53. 54 ancl lock washer 55. A typical dual tire assembly, generally indicated at 58, consists of a l~ai of tires (not shown) mounted on rims either in the form of bud rims 59, 60 (as shown ) Or on a spoke hub assembly not shown. The bud rims 59, 60 are attached by wheel nul~
and studs 62 to hub 43. Hub cap 63 encloses the end of the spindle 42. A brake dl-64 is also connected to hub 43 by studs 62 and the brake drum 64 encases the hr. ke shoes 51. A dust shield 65 is connected to the brake support spider 50. A brake mini (f~
is connected to the brake cam shaft 67.
As noted above the main reason for the detachment of rims 59,60 or h.ll-~
43 is due to the overheating of wheel bearings 45 and 44 due to a lack of lubricant and/or improper bearing load. Accordingly the present invention utilizes sensors 29 that are capable of monitoring the temperature of the wheel assembly on the end of any axle and comparing it to the temperature of the other wheels on the same axle and othel axles as well as a pre-selected maximum permitted temperature. The sensors 29 are al~o capable of monitoring noise, vibration and knocking associated with the each axle ancl wheel hub assembly caused by improper bearing pre-load, a cracked bearing case. looie wheel nuts, broken studs and cracked rims which are also indications of possible5 imminent detachment.
- In Figs. SA and 5B the preferred configuration of sensors 29 is illustrated.
Each sensor 29 consists of a thermally conductive housing 70 into which is mounted a temperature transducer 71 to monitor the temperature of the wheel bearings 44, 45 alld ;
1() vibration transducer 72 for monitoring noise, vibration and knocking. In the prel'erl-e(l embodiment, ~utput lines 73 from each of the temperature transducer 71 and vibratioll transducer 72 e xit the housing through outlet 74. An additional wire 75 is looped willlin the outlet 74 to permit connection to a second remote temperature transducer 76. This second temperature transducer 76 can be encased within a thermally conductive l S housing 76A, sealed with epoxy to prevent moisture and/or ambient air from interfe~ g with the opera~tion of the sensor and mounted adjacent the brake shoes (as showll in Figure 4) to monitor any changes in the temperature of the brakes which may be indicative of a problem. The housing 70 is enclosed by panel 77 and sealed with epoxy to prevent moisture and/or ambient air from interfering with the operation of the sell~ol.
2() The housing 70 and panel 77 are constructed of thermally conductive materials so th.lt any temperature changes caused by overheating of the wheel bearings can be deteclecl by temperature transducer 71. The sensor 29 is secured by screws 78A to a blocl~ 78 which is adapted to be welded to the axle 41 adjacent the wheel assembly. The temperature of the bearings is transmitted through the axle and accordingly the proximity of the sensor 29 and block 78 to the wheel bearings 44, 45 the more reliahle the readings. The housing 70 and panel 77 are pret'erably fabricated from stainless steel (303 SS) to resist corrosion. The block 78 is preferably welded to the axle 41 betwee the hub 43 ancl the brake support spider SO as shown on Figure 4 l he sensors 29 are connected by individual output lines 73. 75 lo a ~en~o module CPU 31 located in proximity to each of the axles. The sensol- module CPUs al e preferably attarhed to the frame of the cab and trailer(s). As shown in Figure 3 the c.lh.
trailer and pup trailer if any are each also equipped with its own fault recording CPU
(FRC)32, 33 and 40 respectively, that communicates with the sensor module CPU for each axle of the cab or trailer or pup trailer. The FRC 32 in the cab has an additional keypad and display 79 used for system initialization and to provide a fault warning ' CA 02226829 1998-02-11 system to alert the driver of any axle problems. Each FRC 32, 33 and 40 i~ al~o equil~pe(l with an interrogation interface 80, 81 and 82 respectively for connection to a hand held terminal or lab top computer. This feature allows interrogation of isolated trailer~ a~ ell as cab/trailer hookups.
s l'he FRC 32 in the cab has a real-time clock 83 for logging date and ~hlle of occurring faults. During initialization of a cab/trailer hookup, the cab FRC 32 will transfer the current date and time to the FRC 33 for the trailer and the FRC 40 fol- thc pup trailer if any. When the cab FRC 32 receives faults from the trailer FRCs 33. 4(). it will respond b~y sending back the date and time for stol-age in the trailer FRC EEPro X4. This eliminates the need for a battery backed-up read time clock on trailer FRC
33,40. The cab FRC 32, maintains battery power to the real time clock flom the cah battery to maintain the time. The time and date can be reset and verified by the drivel-prior to initializing all trailers in the system should the cab battery be disconnected or l'ail l .~ m servlce.
E ach Sensor Module CPU (SMC) 31 will monitor two temperature ~en~ol s 71, 76 (bearin~" brake) and one vibration sensor 72 for each wheel on the axle. Il any wheel generates a suspected fault, the fault code is transmitted by the SMC 31 lo the FRC 32, 33 or 40 for further processing. The FRC is then responsible for verifying ~he fault is true by comparing to all other axles on the trailer/cab. If the fault is valid it i~
then hard recorded in the EEProm 84 and passed on to the cab FRC 32 through a multiplexed connection (MXBUS) 38 for driver warning.
1'he FRC's 32, 33 and 40 can communicate with each other by a variety ol' known means. The FRC's could be connected by wire or co-axial cable however authorities are discouraging additional wire connections between the cab and trailel- all~l restricting wire or cable to the current seven prong connection. Radio receivers all~l transmitters or cellular connections could be utilized however a reliable, secul-e intel-l'.lce 3() without the po.sibility of outside interference or disruption is required.
As shown in Figs. 3 and 7, in the preferred embodiment the FRC?~ 32. 33 and 40, communicate with each other on a multiplexed connection (MXBUS) 38 (see Figs. 3 and 7) chat uses a circuit in the standard seven pin (J560 pin). As noted above in the preferred embodiment a free turn signal lamp wire is utilized for transmitting and receiving data. This is accomplished by pulsing a high frequency carrier on the turll signal wire. Dual frequencies are used, one for receive through receiver 90, and one t'or transmit by transmitter 91 to allow for full duplex communication on the single wire.
These frequency carriers are low voltage, and are detectable even if the signal lamp is pulsing and will not interfere with the turn signals. The MXBUS is a three conductol-S bus, one for signal, one for signal com, one for power. These conductors, can be foul1cl on all truck harnesses that provide the center pin for power to the ABS brakes. For older equipment, the trailer will have to be equipped with a standard lead-acid battery to power the fault recording CPU, this battery could be charged by having the running lights activated for a period of time.
]3y utilizing a multiplexing connection between the cab and trailer~ it i~
possible to incorporate a number of programmable auxiliary features into the syslem. I
accordance with U.S. regulations after March 1, 2001 all tractors must have in-cab warning lights and trailers must be capable of sending a signal to the tractor if there i~; a 15 antilocking braLke system (ABS) malfunction on the trailer. Currently the warning li'gllt i~
located on the trailer. The present invention provides a very effective solution to this requirement. In addition the system can be programmed so that the operator can COlltlOI
from the cab: .Lift axle operation, operate rear door locks, operate emergency stop warning lights on the trailer, operate tail gates, hoppers, valves and chutes, operale ba-li 20 up lights and horn on the trailer. The operator can also from the cab monitor: drive shat't overheating, brake adjustment on the trailer, brake pad wear, trailer reflidgeratioll UllitS.
Ioad shift or weight of the trailer and the like.
All FRC's communicate with their own local SMC's via a sensor module 25 bus (SMBUS) 39. The SMBUS 39 is preferably a four conductor bus utilizing the RS-485 interface standard. The SMBUS includes transmitter 85 and receiver 86 at the FRC
and corresponding transmitter 92 and receiver 93 at the SMC. This interface stalldal (I
implement~ a balanced multi-point transmit/receive communication line ~lsed in a l~art~
line configuralion. This allows the FRC 32 to connect to SMC 31 on axle 20. SMC 3 l 30 on axle 20 to ',MC 31 on axle 21 and so on to the last axle. This feature reduce~ tlle amount of wir.ing harness along the bottom of the cab or trailer.
As shown in Figs. 3 and 7, all the FRC's 32, 33 and 40 communicate with their corresponding Interrogate Terminal 80, 81 and 82 via an interrogate bus (ITGBUS ) 35 87. This bus preferably uses a standard three conductor RS232 communication protocol.
which is availaLble on all standard computer equipment. Again the ITGBUS include~, a transmitter 88 and receiver 89. An extra power plug will be provided by the Interl-o~ e Terminal for connection to a trailer FRC which may be isolated with no existing pOWel.
~s shown in Figure 6, each sensor module CPU 31 has a microconlrolle 5 '- 94 to measure all sensors 29 on its axle and to communicate with the corresponding FRC 32, 33 or 40. A PIC16C74 microcontroller has been used in the preferred embodiment. E,ach SMC 31 is equipped with a silicon hardware ID code 95 tor module identification. This identification number can be transl'erred to and logged in the FRC
EEProm 84 during every initialization.
I() E,ach SMC 31 preferably has a hardware jumper 96 to identify its axle number to the ]FRC. This jumper is preferably set prior to shipping, and SMC's can he identified by a label (ie Axle 1) for installation. An optional EEProm 97 can beconnected to the SMC 31 for programmable identification and calibration parameters.
The SMC 31 program design (Figs. 22 to 28) is broken into two basic areas: Sensor Hardware/Fault Algorithm Design and Software Communication Protocol Design.
2() The Sensor Hardware/Fault Algorithm Design is programmed as follows:
Temperature of the bearings and brakes is measured by sensors 29 preferably using a semi conductor sensor for the bearings and a platinum resistallce probe (RTD) for the brakes. The RTD probe has an operating range of -200~ C to 800~C with an excellent temperature stability of less than 1% over the range- 50~C to 800~C. The platinum RTD probe has a large resistance change output for its operati~
range, 80 ohm, at-50~C to 375 ohms at 800~C with good linearity over that range. By applying a lma reference current to the probe, a voltage output of 60mv to 375 IllV 0\'el the -50~C to 8()0~C range can be achieved. This signal can then be amplified and3() sampled by the coresponding SMC 31 analog/digital (A/D) input: 98 for left bearillg temperature, 9'3 for right bearing temperature~ lO0 for left brake temperature and l O l l'or r i~ht brake temperature. Gain is used to adjust the span of temperature measurement t'or the bearing or brakes. This will also determine the temperature resolution of the A/D
converter within microcontroller 94. The A/D converter in the prefen-ed microcontroller has 256 steps, providing the following resolutions:
E,earing Temperature: 0 to 250 Deg C approx: ldeg/step ' CA 02226829 1998-02-11 Brake Temperature: 0 to 800 Deg C approx: 3 deg/step Ambient tempcrature (TAmbient) is monitored by the FRC 32, 33 and 40 by temperat~ e transducer 102 and then transferred to all sensor module CPU's. A temperature fault will 5 '' exist under the following conditions, where TBearing is the temperature of the bearillg as measured by temperature transducer 71 (Figure 5), TAmbient is the ambient air- tennperature measured by the temperature transducer 102 at the FRC, TBearing Maximum is a pre-selected temperature difference indicative of overheating, TBrakeLet'~
is l:he temperature of the left brake on an axle measured by the second temperatul-c 1() transducer 76 (Figure 6), TBrakeRight is the temperature of the right brake on tllc ~ame axle measured by temperature transducer 76 and TBrake Maximum is a pre-selecteclternperature difference indicative of overheating:
l. TBearing - TAmbient > TBearing Maximum = fault 2. TBrakeLeft-TBrakeRight>TBrakeMaximum = fault 15 ln the preferreci embodiment a TBearing Maximum of 190~F has been selected toinclicate an alarm condition. With respect to the brake temperature, a 30% differential bel~ween the lel't and right brake on an axle is preferably used to indicate an alar m condition .
~,'ibration Knocking vibration on the wheel/axle joint can be measul-ed hy seIlsor 29 using a vibration transducer 72, preferrably a crystal transducer. asschematically illustrated in Figure. S. The transducer 72 produces a voltage proportional to the amplitucle and frequency of the vibration being generated by the wheel/axle joint.
The Xtal signa] (amplitude and time as plotted on the X-Y axis) can be amplified. rectil'ie(l and filtered to leave the low frequency enveloped. The microcontroller is programme(l ~o deltermine a Vibration Fault Condition under the following conditions:
Knock: The Sensor Module CPU 31 can monitor the rectified/filteled signal on it~ A/D
input, 102A for left wheel vibration transducer and and 103 for the right wheel vit r.lti 3() transducer, for a fixed amount of time (ie 10 wheel revolutions) and determine if thel-e i~
a cyclic pattern to the knock by measuring the time duration between pulses. The w l~eel lock signal will help to determine if there is a phase relationship of knock to wheel position regardless of wheel speed. If a phase-locked pattern is detected a fault code i~
sent to the FRC. The FRC would then check other wheels to see if the same fault is occurring on other axles (which would be indicative of road noise). The FRC would monitor the condition for a fixed time interval and if the fault is still valid it is then passed on to the cab FRC to alert driver of possible trouble.
Grind: A continuous high amplitude signal, regardless of wheel position may indicate a 5 ~ bearing grind, and would be used to generate a fault if it is produced for an extendec~
period of time. This would probably be accompanied with increased bearing temperature.
E~ach SMC communicates on the SMBUS with the FRC as tollows.
. The FRC sends out a 4 byte command structure to the SMC
ie. 1. [Axle ID] --axle id number to select the specified SMC.
2. [Command] -- requested action of SMC -- see table below.
3. [Parameter] -- additional command parameter 4. [:] - the end of command character Command Libra1~:
2 0 ~1 Initialize I -- Identify Fault 2 -- Load New Ambient Temp 3 -- Return Left Bearing Temp 4 -- Return Right Bearing Temp 5 -- Return Left Brake Temp 6 -- Return Right Brake Temp 7 -- Return Left Vibration Amplitude 8 -- Return Right Vibration Amplitude 9 -- Return Left Wheel RPM
10- Return Right Wheel RPM
Initialize As illustrated in Figs. 8, 9 and 10, the FRC will send out an initialize command to 35 de~:ermine how many axle SMC's are connected to it. Each SMC during the initialization phase will transmit its Identification Number as acknowledgment to the FRC.
Identify fault 5 - During road operation, as shown in Figure 14 to 21, the FRC will continuously poll all SMC's and request that they inform of any faults present. The SMC will return the following data stream.
[,~xle Number] [Fault Code] [:]
1() 0 -- no fault I -- Temp bearing fault left 2 -- Temp bearing fault right 3 -- Brake fault 4 -- Knock fault left S -- Knock fault right 6 -- Grind fault left 7 -- Grind fault right 20 If a SMC does not respond within a fixed amount of time. a retry is done. if still a failed response, a SMC failure fault is logged and sent to the cab FRC to alert driver.
Load New Amibient This command will transfer to the selected SMC the current ambient temperature for u~
25 in fault condition tests. The temperature number is sent in the parameter byte.
The following 'SMC commands are used for diagnostics and during install setup to ve the selected sellsor is operating.
30 Return Left Bearing Temp This command will return the current temperature for the left bearing on the axle.
Return Right Bearing Temp This command will return the current temperature for the right bearing on the axle.
Return Left Brake Temp This command will return the current temperature for the left brake on the axle.
Return Right E~earing Temp 5 ~ This command will return the current temperature for the right break on the axle.
Return Left Vibration Amplitude This command will return the eurrent vibration amplitude for the left wheel on the axle.
Return Right ~,'ibration Amplitude This command will return the eurrent vibration amplitude for the right wheel on the axle.
Rc turn Left Wheel RPM
This eommand will return the eurrent revolution speed of the left wheel to test the wl~eel lock position i ndicator.
Return Right \~heel RPM
This command will return the eurrent revolution speed of the right wheel to test the wheel lock position indieator.
E aeh FRC 32, 33,40 as shown in Figure 7 uses a microcontroller 14 preferably a PICI6C74 mieroeontroller, as the center communication hub between ~Cab/Trailers F]RCs, SMCs and Interrogation Terminals. Each FRC is equipped with a Silieon Hardware ID Code 105 for module identification. This identification numher ~
be tagged with a Vehiele identification number during installation which will be stol-e(l in EEProm 84. Each FRC will have a 64x8 bit Serial EEProm 84 for logging fault er1ol-codes, with a capacity of 1000 fault records before recycling and removing old reading~.
Each FRC connects to three interface buses, MXBUS 38, SMBUS 39 and the ITGBUS
87. The FRC in the cab will also have a display 79, keyboard 106 and audio alar system interface 107 with additional firmware to support this interface.
Fault Recording Module Design (Figures 8 to 21) can be broken down into 4 ba~ic areas.
F ault Recording Data Format ~XBus System Protocol S,MBus System Protocol (described earlier in SMC description) ITGBus System Protocol Fault Recording Data Format: Every fault that is verified by the FRC is stored in EE,Prom, in a 1000 fault circular buffer. When the bulfer reaches maximum capacity. the 5 olclest records are removed when new ones are added. Each fault is packed in a gl-o~
of 8 data bytes as follows.
By te o Year Byte 1 ~lonth 1() Byte 2 Day Byte 3 1[r Byte 4 Min By te 5 Fault Id Byte 6 Driver Acknowledged Status Byte 7 Reserved MXBUS Protocol: All FRC's communicate with each other on the MXBUS. The Cab FR.C is the System Host and controls all data transfers on the MXBUS. The Cab FRC is responsible for identifying all FRC's connected to the MXBUS. This is done by sellclillg 2() out an identify command during the initialization process. Trailers will be identified bv the T suffix and Pup trailers will be identified by the P suffix and Cabs identified by lhe C suffix.. During the install setup each FRC is programmed with its appropriate sui't'i~.
During the Initialization process, the cab CPU will start in sequence and ask for the identification number of all Trailers/Pups, and to report how many axles each contl-ols.
25 In the special case of a multiple trailer hookup, the cab CPU will assign one of the trailel-s a new ID code for communication on the MXBUS. Every Trailer will have a name llhlle attached to it during install setup, for easy identification of a trailer fault for multi-traile configuration. To avoid data collisions in a multi-trailer hookup (ie ~ T sut'tixes). a r andom time response seed table will be programmed into each FRC s EEProm so thal i l' 3() a transfer is nol: successful on first pass, it will delay a random amount of thlle and ~r~
ag;lin till communication is established and a valid ID number has been assigned.
The Cab FRC will continuously poll all FRC's in the system to ask if an~
faults are present. If a fault is indicated the Cab FRC will then inform the driver with an 35 audio alarm, a visual message displaying the fault detected on the LCD display panels.
ie ID AXLE SIDE FAULT
T o 1 LEFT BEARING
E' 0 2 RIGHT KNOCK
S -Note: On multi-trailer hookups, the ID would display the FRC ID number which wo~lld match the name plate on the trailer.
ï'he driver would then press an acknowledge key to clear the error codc 10 afler inspection, and the alarm will turn off. If the same t'ault is indicated again, the al.~
will sound again, after the third time the alarm will be di!iabled and only a visual mes~a(Te will be displayed.
l'he acknowledge data byte in the fault data record will keep track ol' tlle 15 number of responses by the driver to the same fault.
The CAB FRC will use a multi byte command structure for communicati on the MXBUS. All commands strings are truncated with a:
[Trailer ID] [Command] [Parameter] [:]
20 Trailer ID specifies which trailer should talk. Command specifies what function the trailel-should execute. The Parameter string contains any additional data.
Command Library 0 Initialize [trailer FRC should return its internal FRC ID nLIlllhcl-ID Acknowledge [ID has been verit'ied]
3 Report Axle [trailer should respond with the axle count]
Count 2 Identify fault [Ask for any Faults detected, same as SMC fault co(le~
3 () 3 Time Record [Time transfer to Trailer FRC for fault record]
Fault ITIJBUS Protocol: The ITGBUS is a standard RS232C interface to allow all the EEPROM data in the FRC to be interrogated and to allow for remote operation of the 35 FRC unit. This can be done using a specially designed hand held unit, or any IBM
computer terminal Having illustrated and described a preferred embodiment of the invention and certain possible modifications thereto, it should be apparent to those ol' ordinary skill in the art that the invention permits of further modification in arrangement and detail. All such modifications are covered by the scope of the invention.
Initialize As illustrated in Figs. 8, 9 and 10, the FRC will send out an initialize command to 35 de~:ermine how many axle SMC's are connected to it. Each SMC during the initialization phase will transmit its Identification Number as acknowledgment to the FRC.
Identify fault 5 - During road operation, as shown in Figure 14 to 21, the FRC will continuously poll all SMC's and request that they inform of any faults present. The SMC will return the following data stream.
[,~xle Number] [Fault Code] [:]
1() 0 -- no fault I -- Temp bearing fault left 2 -- Temp bearing fault right 3 -- Brake fault 4 -- Knock fault left S -- Knock fault right 6 -- Grind fault left 7 -- Grind fault right 20 If a SMC does not respond within a fixed amount of time. a retry is done. if still a failed response, a SMC failure fault is logged and sent to the cab FRC to alert driver.
Load New Amibient This command will transfer to the selected SMC the current ambient temperature for u~
25 in fault condition tests. The temperature number is sent in the parameter byte.
The following 'SMC commands are used for diagnostics and during install setup to ve the selected sellsor is operating.
30 Return Left Bearing Temp This command will return the current temperature for the left bearing on the axle.
Return Right Bearing Temp This command will return the current temperature for the right bearing on the axle.
Return Left Brake Temp This command will return the current temperature for the left brake on the axle.
Return Right E~earing Temp 5 ~ This command will return the current temperature for the right break on the axle.
Return Left Vibration Amplitude This command will return the eurrent vibration amplitude for the left wheel on the axle.
Return Right ~,'ibration Amplitude This command will return the eurrent vibration amplitude for the right wheel on the axle.
Rc turn Left Wheel RPM
This eommand will return the eurrent revolution speed of the left wheel to test the wl~eel lock position i ndicator.
Return Right \~heel RPM
This command will return the eurrent revolution speed of the right wheel to test the wheel lock position indieator.
E aeh FRC 32, 33,40 as shown in Figure 7 uses a microcontroller 14 preferably a PICI6C74 mieroeontroller, as the center communication hub between ~Cab/Trailers F]RCs, SMCs and Interrogation Terminals. Each FRC is equipped with a Silieon Hardware ID Code 105 for module identification. This identification numher ~
be tagged with a Vehiele identification number during installation which will be stol-e(l in EEProm 84. Each FRC will have a 64x8 bit Serial EEProm 84 for logging fault er1ol-codes, with a capacity of 1000 fault records before recycling and removing old reading~.
Each FRC connects to three interface buses, MXBUS 38, SMBUS 39 and the ITGBUS
87. The FRC in the cab will also have a display 79, keyboard 106 and audio alar system interface 107 with additional firmware to support this interface.
Fault Recording Module Design (Figures 8 to 21) can be broken down into 4 ba~ic areas.
F ault Recording Data Format ~XBus System Protocol S,MBus System Protocol (described earlier in SMC description) ITGBus System Protocol Fault Recording Data Format: Every fault that is verified by the FRC is stored in EE,Prom, in a 1000 fault circular buffer. When the bulfer reaches maximum capacity. the 5 olclest records are removed when new ones are added. Each fault is packed in a gl-o~
of 8 data bytes as follows.
By te o Year Byte 1 ~lonth 1() Byte 2 Day Byte 3 1[r Byte 4 Min By te 5 Fault Id Byte 6 Driver Acknowledged Status Byte 7 Reserved MXBUS Protocol: All FRC's communicate with each other on the MXBUS. The Cab FR.C is the System Host and controls all data transfers on the MXBUS. The Cab FRC is responsible for identifying all FRC's connected to the MXBUS. This is done by sellclillg 2() out an identify command during the initialization process. Trailers will be identified bv the T suffix and Pup trailers will be identified by the P suffix and Cabs identified by lhe C suffix.. During the install setup each FRC is programmed with its appropriate sui't'i~.
During the Initialization process, the cab CPU will start in sequence and ask for the identification number of all Trailers/Pups, and to report how many axles each contl-ols.
25 In the special case of a multiple trailer hookup, the cab CPU will assign one of the trailel-s a new ID code for communication on the MXBUS. Every Trailer will have a name llhlle attached to it during install setup, for easy identification of a trailer fault for multi-traile configuration. To avoid data collisions in a multi-trailer hookup (ie ~ T sut'tixes). a r andom time response seed table will be programmed into each FRC s EEProm so thal i l' 3() a transfer is nol: successful on first pass, it will delay a random amount of thlle and ~r~
ag;lin till communication is established and a valid ID number has been assigned.
The Cab FRC will continuously poll all FRC's in the system to ask if an~
faults are present. If a fault is indicated the Cab FRC will then inform the driver with an 35 audio alarm, a visual message displaying the fault detected on the LCD display panels.
ie ID AXLE SIDE FAULT
T o 1 LEFT BEARING
E' 0 2 RIGHT KNOCK
S -Note: On multi-trailer hookups, the ID would display the FRC ID number which wo~lld match the name plate on the trailer.
ï'he driver would then press an acknowledge key to clear the error codc 10 afler inspection, and the alarm will turn off. If the same t'ault is indicated again, the al.~
will sound again, after the third time the alarm will be di!iabled and only a visual mes~a(Te will be displayed.
l'he acknowledge data byte in the fault data record will keep track ol' tlle 15 number of responses by the driver to the same fault.
The CAB FRC will use a multi byte command structure for communicati on the MXBUS. All commands strings are truncated with a:
[Trailer ID] [Command] [Parameter] [:]
20 Trailer ID specifies which trailer should talk. Command specifies what function the trailel-should execute. The Parameter string contains any additional data.
Command Library 0 Initialize [trailer FRC should return its internal FRC ID nLIlllhcl-ID Acknowledge [ID has been verit'ied]
3 Report Axle [trailer should respond with the axle count]
Count 2 Identify fault [Ask for any Faults detected, same as SMC fault co(le~
3 () 3 Time Record [Time transfer to Trailer FRC for fault record]
Fault ITIJBUS Protocol: The ITGBUS is a standard RS232C interface to allow all the EEPROM data in the FRC to be interrogated and to allow for remote operation of the 35 FRC unit. This can be done using a specially designed hand held unit, or any IBM
computer terminal Having illustrated and described a preferred embodiment of the invention and certain possible modifications thereto, it should be apparent to those ol' ordinary skill in the art that the invention permits of further modification in arrangement and detail. All such modifications are covered by the scope of the invention.
Claims (39)
1. A monitoring system for detecting problems associated with the wheelson vehicle axles comprising one or more sensors located on the vehicle axles adjacent the wheels, a programmable micro processor for receiving and processing the sensor signals to detect an alarm condition and alarm means to alert the driver of a problem with one or more of the wheels.
2. Apparatus according to claim 1 wherein said sensors detect heat, noise and/or vibration.
3. Apparatus according to claim 2 wherein said sensors are located within the wheel hub and brake pads.
4. Apparatus according to claim 3 wherein said micro processor monitors changes in the heat, noise and vibration detected by the sensors and determines when an alarm condition exists.
5. Apparatus according to claim 4 wherein the alarm means comprises a micro processor annunciator capable of giving an audio. visual alarm to alert the operator an alarm condition exists.
6. A networked microcontroller based system for monitoring and recordingoperating axle faults for a multi axle vehicle where each of the axles on the vehicle has wheels and brakes at both ends of said axles, said system comprising sensors capable of monitoring heat, noise, vibration and shocks associated with said axles, brakes and wheels mounted on each axle, one or more sensor CPUs connected to the sensors monitoring the axles and wheels and brakes, a fault recording CPU connected to said sensor CPUs, said fault recording CPU having a keypad and display for system initialization and a fault warning means.
7. A networked microcontroller based system for monitoring and recordingoperating axle faults for a heavy vehicle cab and trailer hookup, where said cab has at least two cab axles with wheels and brakes at both ends of said cab axles and said trailer has one or more trailer axles with wheels and brakes at both ends of said trailer axles.
comprising sensors capable of monitoring heat, noise, vibration and shocks associated with said axles, brakes and wheels mounted on each cab axle and each trailer axle, one or more cab sensor CPUs connected to the sensors monitoring the cab axles and wheels and brakes, one or more trailer sensor CPUs connected to the sensors monitoring the trailer axles and wheels and brakes, a cab fault recording CPU connected to said cab sensor CPUs, a trailer fault recording CPU connected to said trailer sensor CPUs, said cab fault recording CPU having a keypad and display for system initialization and a fault warning and means to permit the cab fault recording CPU and trailer fault recording CPU to communicate with each other.
comprising sensors capable of monitoring heat, noise, vibration and shocks associated with said axles, brakes and wheels mounted on each cab axle and each trailer axle, one or more cab sensor CPUs connected to the sensors monitoring the cab axles and wheels and brakes, one or more trailer sensor CPUs connected to the sensors monitoring the trailer axles and wheels and brakes, a cab fault recording CPU connected to said cab sensor CPUs, a trailer fault recording CPU connected to said trailer sensor CPUs, said cab fault recording CPU having a keypad and display for system initialization and a fault warning and means to permit the cab fault recording CPU and trailer fault recording CPU to communicate with each other.
8. A system according to claim 7 wherein the means to permit the cab fault recording CPU and trailer fault recording CPU to communicate with each other consists of a multiplex bus.
9. A system according to claim 8 wherein the multiplex bus uses one of the circuits on the standard seven pin connection between the cab and trailer for transmitting and receiving data.
10. A system according to claim 9 wherein the multiplex bus uses a free turn signal lamp wire for transmitting and receiving data.
11. A system according to claim 7 wherein the cab fault recording CPU andthe trailer fault recording CPU are equipped with an interrogation interface forconnection to another computer.
12. A system according to claim 6 wherein each sensor includes a temperature transducer located on each axle adjacent the wheels to monitor the temperature of the bearings of the wheels at the end of each axle.
13. A system according to claim 11 wherein each sensor includes a second temperature transducer located remote from said temperature transducer adjacent the brakes to monitor any changes in the temperature of the brakes.
14. A system according to claim 12 wherein each sensor includes a vibration transducer for monitoring noise, vibration and knocking.
15. A system according to claim 14 wherein the first temperature transducer and the vibration transducer are sealed in a housing.
16. A system according to claim 12 wherein when the temperature of the bearings of a wheel exceeds ambient air temperature by a selected amount a faultwarning is displayed on the fault recording CPU.
17. A system according to claim 13 wherein when the difference between the brakes on one end of an axle exceeds the temperature of the brakes on the other end of the same axle exceeds a selected amount a fault warning is displayed on the fault recording CPU.
18. A system according to claim 12 wherein the fault recording CPUs compare the temperature of the bearings on each axle to the temperature of the bearings on every other axle before indicating a fault.
19. A system according to claim 14 wherein the sensor module CPU is programmed to determine if there is a cyclic pattern to any knock detected by measuring the time between pulses and the fault recording CPU checks the other axles before signaling a fault.
20. A system according to claim 19 wherein detection of a continuous highamplitude noise signal will generate a fault.
21. A system according to claim 7 wherein the fault recording CPU is programable to control or monitor one or more auxilary functions selected from the group consisting of in-cab warning lights in response to a signal from the trailer to the cab if there is an antilocking brake system (ABS) malfunction on the trailer, lift axle operation, rear door locks, emergency stop warning lights on the trailer, tail gates.
hoppers, valves and chutes, back up lights and horn on the trailer, drive shaft overheating, brake adjustment on the trailer, brake pad wear, trailer refridgeration units.
load shift or weight of the trailer and the like.
hoppers, valves and chutes, back up lights and horn on the trailer, drive shaft overheating, brake adjustment on the trailer, brake pad wear, trailer refridgeration units.
load shift or weight of the trailer and the like.
22. A system according to claim 2 wherein each sensor includes a temperature transducer located on each axle adjacent the wheels to monitor the temperature of the bearings of the wheels at the end of each axle.
23. A system according to claim 22 wherein each sensor includes a second temperature transducer located remote from said temperature transducer adjacent the brakes to monitor any changes in the temperature of the brakes.
24. A system according to claim 23 wherein each sensor includes a vibration transducer for monitoring noise, vibration and knocking.
25. A system according to claim 24 wherein the first temperature transducer and the vibration transducer are sealed in a housing.
26. A system according to claim 25 consisting of a networked microcontroller based system for monitoring and recording operating axle faults for a multi axle vehicle where each of the axles on the vehicle has wheels and brakes at both ends of said axles said system comprising sensors capable of monitoring heat, noise, vibration and shocks associated with said axles, brakes and wheels mounted on each axle, one or more sensor CPUs connected to the sensors monitoring the axles and wheels and brakes, a fault recording CPU connected to said sensor CPUs, said fault recording CPU having a keypad and display for system initialization and a fault warning means.
27. A networked microcontroller based system according to claim 26 for monitoring and recording operating axle faults for a heavy vehicle cab and trailer hookup, where said cab has at least two cab axles with wheels and brakes at both ends of said cab axles and said trailer has one or more trailer axles with wheels and brakes at both ends of said trailer axles, comprising sensors capable of monitoring heat, noise.
vibration and shocks associated with said axles, brakes and wheels mounted on each cab axle and each trailer axle, one or more cab sensor CPUs connected to the sensors monitoring the cab axles and wheels and brakes, one or more trailer sensor CPUs connected to the sensors monitoring the trailer axles and wheels and brakes, a cab fault recording CPU connected to said cab sensor CPUs, a trailer fault recording CPU
connected to said trailer sensor CPUs, said cab fault recording CPU having a keypad and display for system initialization and a fault warning and means to permit the cab fault recording CPU and trailer fault recording CPU to communicate with each other.
vibration and shocks associated with said axles, brakes and wheels mounted on each cab axle and each trailer axle, one or more cab sensor CPUs connected to the sensors monitoring the cab axles and wheels and brakes, one or more trailer sensor CPUs connected to the sensors monitoring the trailer axles and wheels and brakes, a cab fault recording CPU connected to said cab sensor CPUs, a trailer fault recording CPU
connected to said trailer sensor CPUs, said cab fault recording CPU having a keypad and display for system initialization and a fault warning and means to permit the cab fault recording CPU and trailer fault recording CPU to communicate with each other.
28. A system according to claim 27 wherein the means to permit the cab fault recording CPU and trailer fault recording CPU to communicate with each other consists of a multiplex bus.
29. A system according to claim 28 wherein the multiplex bus uses a free turn signal lamp wire for transmitting and receiving data.
30. A system according to claim 27 wherein the cab fault recording CPU and the trailer fault recording CPU are equipped with an interrogation interface forconnection to another computer.
31. A system according to claim 27 wherein when the temperature of the bearings of a wheel exceeds ambient air temperature by a selected amount a faultwarning is displayed on the fault recording CPU.
32. A system according to claim 31 wherein when the difference between the brakes on one end of an axle exceeds the temperature of the brakes on the other end of the same axle exceeds a selected amount a fault warning is displayed on the fault recording CPU.
33. A system according to claim 32 wherein the fault recording CPUs compare the temperature of the bearings on each axle to the temperature of the bearings on every other axle before indicating a fault.
34. A system according to claim 28 wherein the sensor module CPU is programmed to determine if there is a cyclic pattern to any knock detected by measuring the time between pulses and the fault recording CPU checks the other axles before signaling a fault.
35. A system according to claim 34 wherein detection of a continuous highamplitude noise signal will generate a fault.
36. A system according to claim 28 wherein the fault recording CPU is programable to control one or more auxilary functions selected from the group consisting of in-cab warning lights in response to a signal from the trailer to the cab if there is an antilocking brake system (ABS) malfunction on the trailer, lift axle operation.
rear door locks, emergency stop warning lights on the trailer, tail gates, hoppers, valves and chutes, back up lights and horn on the trailer, drive shaft overheating, brake adjustment on the trailer, brake pad wear, trailer refridgeration units, load shift or weight of the trailer and the like..
rear door locks, emergency stop warning lights on the trailer, tail gates, hoppers, valves and chutes, back up lights and horn on the trailer, drive shaft overheating, brake adjustment on the trailer, brake pad wear, trailer refridgeration units, load shift or weight of the trailer and the like..
37. A communication system for tractor trailers comprising a cab CPU
incorporating a transmitter/receiver and a trailer CPU incorporating a transmitter receiver wherein said cab CPU and said trailer CPU communicate with each other on a multiplex bus.
incorporating a transmitter/receiver and a trailer CPU incorporating a transmitter receiver wherein said cab CPU and said trailer CPU communicate with each other on a multiplex bus.
38. A communication system according to claim 37 wherein the multiplex bus uses a free turn signal lamp wire for transmitting and receiving data.
39. A communication system according to claim 37 wherein the cab CPU is programmable to control or monitor one or more auxilary functions on said trailer selected from the group consisting of in-cab warning lights in response to a signal from the trailer to the cab if there is an antilocking brake system (ABS) malfunction on the trailer, lift axle operation, rear door locks, emergency stop warning lights on the trailer, tail gates, hoppers, valves and chutes, back up lights and horn on the trailer, drive shaft overheating, brake adjustment on the trailer, brake pad wear, trailer refridgeration units.
load shift or weight of the trailer and the like..
load shift or weight of the trailer and the like..
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2226829 CA2226829C (en) | 1997-03-11 | 1998-02-11 | Early warning device for tire rims and hub assemblies |
| PCT/CA1998/000193 WO1998040230A1 (en) | 1997-03-11 | 1998-03-11 | Early warning system for tire rims and hub assemblies |
| EP98907782A EP0898516A1 (en) | 1997-03-11 | 1998-03-11 | Early warning system for tire rims and hub assemblies |
| AU66050/98A AU738418B2 (en) | 1997-03-11 | 1998-03-11 | Early warning system for tire rims and hub assemblies |
| ZA9900083A ZA9983B (en) | 1998-02-11 | 1999-01-06 | Early warning system for tire rims and hub assemblies. |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2,199,649 | 1997-03-11 | ||
| CA002199649A CA2199649A1 (en) | 1997-03-11 | 1997-03-11 | Wheel monitoring device |
| CA 2226829 CA2226829C (en) | 1997-03-11 | 1998-02-11 | Early warning device for tire rims and hub assemblies |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2226829C true CA2226829C (en) | 2000-08-29 |
Family
ID=25679112
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2226829 Expired - Lifetime CA2226829C (en) | 1997-03-11 | 1998-02-11 | Early warning device for tire rims and hub assemblies |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0898516A1 (en) |
| AU (1) | AU738418B2 (en) |
| CA (1) | CA2226829C (en) |
| WO (1) | WO1998040230A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6266586B1 (en) | 1999-12-08 | 2001-07-24 | Allain Gagnon | Vehicle wheel vibration monitoring system |
| US6784793B2 (en) | 2001-06-04 | 2004-08-31 | Allain Gagnon | Vehicle wheel vibration monitoring system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6892778B2 (en) * | 2003-09-09 | 2005-05-17 | Mark K. Hennig | Wheel end assembly high-temperature warning system |
| AU2003266418A1 (en) * | 2003-09-16 | 2005-04-06 | Taipale Automotive Oy | An arrangement to acoustically observe the condition of vehicle wheels |
| CN109606332B (en) * | 2018-11-27 | 2021-08-03 | 江苏大学 | Hybrid theory-based trailer type motor home braking force distribution control system and control method |
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| US4065751A (en) * | 1976-10-18 | 1977-12-27 | General Motors Corporation | Warning circuit for a tractor/trailer combination |
| JPS59187241A (en) * | 1983-04-07 | 1984-10-24 | Shinko Electric Co Ltd | Detecting device of flat of wheel |
| US5140858A (en) * | 1986-05-30 | 1992-08-25 | Koyo Seiko Co. Ltd. | Method for predicting destruction of a bearing utilizing a rolling-fatigue-related frequency range of AE signals |
| DE3709981A1 (en) * | 1987-03-26 | 1988-10-06 | Opel Adam Ag | Monitoring device for detecting anomalous pressure ratios in vehicle tyres |
| DE3718471A1 (en) * | 1987-06-02 | 1988-12-22 | Christoph Breit | DEVICE FOR PROTECTING THE AGGREGATE AND THE LOADING OF MOTOR VEHICLES |
| DE3813494A1 (en) * | 1988-04-22 | 1989-11-09 | Bayerische Motoren Werke Ag | Device for determining the temperature of periodically moved motor-vehicle components |
| US4943798A (en) * | 1989-08-26 | 1990-07-24 | Wayman Wayne | Large truck remote wheel trouble warning system |
| DE4019501A1 (en) * | 1989-09-30 | 1991-04-11 | Lehn F Heinrich | METHOD AND DEVICE FOR VIBRATION MONITORING OF THE WHEEL SYSTEMS OF MOTOR VEHICLES DURING DRIVING |
| DE4009540A1 (en) * | 1990-03-24 | 1991-09-26 | Teves Gmbh Alfred | TIRE PRESSURE MONITORING METHOD AND SYSTEM |
| DE4014561A1 (en) * | 1990-05-04 | 1991-11-07 | Teves Gmbh Alfred | CONTROL SYSTEM FOR MOTOR VEHICLES |
| DE4014876A1 (en) * | 1990-05-09 | 1991-11-14 | Bayerische Motoren Werke Ag | METHOD AND DEVICE FOR DETERMINING AND / OR MONITORING THE CONDITION OF A TECHNICAL COMPONENT OF A MOTOR VEHICLE |
-
1998
- 1998-02-11 CA CA 2226829 patent/CA2226829C/en not_active Expired - Lifetime
- 1998-03-11 WO PCT/CA1998/000193 patent/WO1998040230A1/en not_active Application Discontinuation
- 1998-03-11 EP EP98907782A patent/EP0898516A1/en not_active Withdrawn
- 1998-03-11 AU AU66050/98A patent/AU738418B2/en not_active Ceased
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6266586B1 (en) | 1999-12-08 | 2001-07-24 | Allain Gagnon | Vehicle wheel vibration monitoring system |
| US6784793B2 (en) | 2001-06-04 | 2004-08-31 | Allain Gagnon | Vehicle wheel vibration monitoring system |
Also Published As
| Publication number | Publication date |
|---|---|
| AU738418B2 (en) | 2001-09-20 |
| AU6605098A (en) | 1998-09-29 |
| EP0898516A1 (en) | 1999-03-03 |
| WO1998040230A1 (en) | 1998-09-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20180212 |