CN1982097B - Reliable remote tire pressure monitoring system with tire monitors operating in power saving mode - Google Patents

Abstract

A remote tire pressure monitoring system includes a tire monitor, a receiver, a transmitter, and a controller. The tire monitor is configured to operate in a power saving mode, in which it senses inflation pressure of a tire, determines a change in the inflation pressure of the tire, and transmits a pressure transmitting signal only when the determined change in the inflation pressure is greater than or equal to a predetermined threshold. The controller is operatively connected with the receiver and the transmitter. The controller works to determine, upon receipt of the pressure transmitting signal by the receiver, the inflation pressure of the tire based on the pressure transmitting signal. The controller also works to control, in response to receipt of the pressure transmitting signal by the receiver, the transmitter to transmit the acknowledge signal to inform the tire monitor that the receiver has certainly received the pressure transmitting signal.

Description

Reliable remote tire pressure monitoring system with tire monitors operating in power saving mode

Related application

It is preceence that the application requires the Japanese patent application No.2005-265236 of application on September 13rd, 2005 and the Japanese patent application No.2005-272303 of application on September 13rd, 2005, quotes its content here.

Technical field

The present invention relates generally to the tire air pressure monitoring system of vehicle.More specifically, the present invention relates to the remote tire pressure monitoring system of vehicle, it comprises a plurality of tire monitors operatings, is configured to work under battery saving mode and monitoring to the reliable and near real time of the inflation pressure of vehicle tyre can be provided.

Background technology

For example the disclosed remote tire monitored control system that is used for vehicle generally includes a plurality of tire monitors operatings and a receptor in the U.S. Patent No. 5602524.

Each tire monitors operating all is installed in a plurality of wheels of vehicle one, and comprises pressure sensor and projector.Pressure sensor is used for the inflation pressure that sensing is installed in the tire on the wheel.Projector is used to launch the pressure transmission signal, and this signal comprises the information of the relevant inflation pressure of tire of pressure sensor institute sensing.

Receptor is installed on the car body.Receptor is configured to receive the pressure transmission signal of tire monitors operating emission, information in the pressure transmission signal that receives according to being included in is determined the inflation pressure of tire, and, for example inform the determined inflation pressure of tire of vehicle driver by read out instrument according to the different program of determined inflation pressure of tire execution.

In this remote tire pressure monitoring system, each tire monitors operating is all usually by the powered battery that is arranged on the same wheel.For the service life of guaranteeing that when reducing battery size (being capacity) it is long, need to reduce the power consumption of tire monitors operating.

In order to satisfy above-mentioned requirements, three kinds of methods have been proposed.

First method is to reduce the power consumption of the IC (integrated circuit) that uses in the tire monitors operating by advanced person's technology.

Yet usually, the major part of the whole power consumptions of tire monitors operating all causes that by emission pressure transmission signal having only sub-fraction is that IC is in causing.Even therefore finally reduced the power consumption of IC, still deficiency is so that whole power consumptions of tire monitors operating are reduced to required value.

Second method is to reduce the emitting times of pressure transmission signal by the use control monitor unit (for example acceleration pick-up) that travels.Particularly, use the control monitor unit that travels to provide that to close vehicle be to travel or be in static information as tire monitors operating; Therefore, tire monitors operating is emission pressure transmission signal when vehicle ' only, thereby reduces the emitting times of pressure transmission signal.

Yet,, need tire monitors operating when vehicle ', to launch the pressure transmission signal on enough short time gap intercycle ground for the information of relevant inflation pressure of tire is provided for receptor in real time.Therefore, second method can limit the minimizing of pressure transmission signal emitting times, thus the reduction of restriction tire monitors operating power consumption.

The third method is by using flip flop equipment to reduce the emitting times that transmits.Particularly, flip flop equipment is installed on the car body and is used to launch energizing signal; Tire monitors operating also comprises receptor, is used to receive this energizing signal.When receptor needed the information of relevant inflation pressure of tire, receptor was controlled this flip flop equipment emission energizing signal, triggered the projector emission pressure transmission signal of tire monitors operating.

Because only when needing the signal of relevant inflation pressure of tire, receptor just launches the pressure transmission signal, thus can reduce the emitting times of pressure transmission signal significantly, thus make the power consumption of tire monitors operating be reduced to satisfied level.

Yet the third method can not realize the real-time monitoring to inflation pressure of tire.Particularly, according to the third method, the emitting times of the projector of tire monitors operating emission pressure transmission signal is determined by receptor, rather than is determined by tire monitors operating.Therefore, when inflation pressure of tire occurring in the time gap between any twice continuous emission period of being determined by receptor and obviously change, the change of this inflation pressure of tire can not be passed in the receptor immediately.Can postpone to take the adaptation measure at variation the time lag that this inflation pressure of tire variation is communicated to receptor.

Summary of the invention

The present invention is proposed in view of the above problems.

Therefore, the purpose of this invention is to provide a kind of remote tire pressure monitoring system that is used for vehicle, it comprises that power consumption is less than the tire monitors operating of the tire monitors operating of existing remote tire pressure monitoring system.

Another object of the present invention provides the remote tire pressure monitoring system that is used for vehicle, and it can provide to the inflation pressure of tire of vehicle reliably and almost real-time monitoring.

To achieve these goals, the present inventor at first studies the different variation patterns of inflation pressure of tires of vehicle.

First kind of mode is the quick variation that is caused by for example tyre explosion; The second way is the variation at a slow speed of leaking gas and causing by naturally; The third mode is the running modification that is caused by air themperature running modification in the tire when the vehicle '.

In the almost whole service life of tire, second kind of variation pattern only takes place in inflation pressure of tire; The third variation pattern took place in service life in minority; And first kind of variation pattern is rare.

In view of top described, the contriver considers that the tire monitors operating of remote tire pressure monitoring system need not to launch the pressure transmission signal of expression inflation pressure of tire, unless there is the quick variation of inflation pressure of tire.

Particularly, consideration according to the contriver, tire monitors operating can so be disposed: it launches the pressure transmission signal immediately one time after vehicle ignition switch is opened, and the receptor of remote tire pressure monitoring system can be determined the initial value of inflation pressure of tire when receiving the pressure transmission signal like this; Afterwards, it just launches the pressure transmission signal when the quick variation that has inflation pressure of tire.

In other words, utilize this structure, tire monitors operating will not launched the pressure transmission signal when second kind of variation pattern only takes place inflation pressure of tire.As a result, can reduce the emitting times of pressure transmission signal significantly, thereby make the power consumption of tire monitors operating be reduced to satisfactory level.

In addition, when the pressure transmission signal that do not exist from tire monitors operating emission, receptor determines that inflation pressure of tire does not take place to change fast, and in other words, inflation pressure of tire almost remains unchanged.On the contrary, when inflation pressure of tire took place to change fast, tire monitors operating was launched the pressure transmission signal immediately, and receptor can learn in time that inflation pressure of tire changes like this.

In addition, during the quick variation of inflation pressure of tire, tire monitors operating can be launched the pressure transmission signal with short time gap (for example 1 second) circulation, and can significantly not increase the total quantity of launching the pressure transmission signal.

As a result, utilize said structure, tire monitors operating just may offer receptor with the information of relevant inflation pressure of tire in almost real-time mode.

In addition, offer the high reliability of receptor in order to ensure the information with relevant inflation pressure of tire, this remote tire pressure monitoring system also can so be disposed: the reception that the receptor response pressure transmits signal comes the transmitting acknowledgement signal; When receiving acknowledgment signal, tire monitors operating determines that the pressure transmission signal of its emission is received by the receiver.

Usually, if the data in one of two different devices are automatically updated into the data in another device, then the link between two different devices (or operation) is hot link.

Therefore, utilize said structure, just may between tire monitors operating and receptor, set up failure-free " the hot link of pressure ".

The present invention is that the above-mentioned consideration by the contriver draws.

According to the present invention, a kind of remote tire pressure monitoring system is provided, it comprises tire monitors operating, receptor, projector and controller.

Tire monitors operating is arranged on the wheel of vehicle.Tire monitors operating can be operated under battery saving mode, wherein the tire monitors operating sensing is contained in inflation pressure of tire on the wheel under battery saving mode, determine the variation of inflation pressure of tire, and only just launch the pressure transmission signal of the information of the relevant inflation pressure of tire that comprises institute's sensing during more than or equal to predetermined threshold in the variation of determined inflation pressure of tire.

Receptor is used to receive the pressure transmission signal of tire monitors operating emission.

Projector is used for the transmitting acknowledgement signal.

Controller operationally links to each other with projector with receptor.Controller is used for determining inflation pressure of tire according to the information that is included in the pressure transmission signal when receptor receives the pressure transmission signal.Controller also is used for controlling projector transmitting acknowledgement signal in response to receptor reception pressure transmission signal and has received the pressure transmission signal with notice tire monitors operating receptor.

Utilize said structure, can reduce the emitting times of pressure transmission signal significantly, thereby reduce the power consumption of tire monitors operating significantly.

In addition, when inflation pressure of tire generation significant change, this variation can be delivered to controller immediately, thereby can realize the almost real-time monitoring to inflation pressure of tire.

In addition, use acknowledgment signal, just may guarantee provides the high reliability of the information of relevant inflation pressure of tire to controller from tire monitors operating.

Therefore, utilize said structure, can between tire monitors operating and controller, set up the hot link of reliable pressure, reduce the power consumption of tire monitors operating simultaneously significantly.

Preferably, under battery saving mode, tire monitors operating is the air themperature in the sensing tire also, determine the variation of air themperature in the tire, and only the variation of determined inflation pressure of tire more than or equal to predetermined threshold and determined tire in the variation of air themperature just launch the pressure transmission signal during less than second predetermined threshold.

Utilize this structure, when the variation of inflation pressure of tire be not by tire in amount of air change fast cause the time, just may prevent that tire monitors operating from unnecessarily launching the pressure transmission signal, thereby avoid waste electric energy.

Also preferably, under battery saving mode, if do not receive affirmation signal from projector in the predetermined period of time of tire monitors operating behind emission pressure transmission signal, then tire monitors operating is launched the pressure transmission signal again.

Utilize this structure, just may pressure boost transmit the possibility that signal is received by the receiver.

Also preferably, under battery saving mode, if tire monitors operating is not received the affirmation signal from projector after launching pressure transmission signal pre-determined number again, then tire monitors operating is transformed into the cycle emission mode with its operation from battery saving mode, and tire monitors operating is launched the pressure transmission signal with the predetermined time interval cycle under the cycle emission mode.

Utilize this structure, because emitter failures or ambient noise and can not the confirmation of receipt signal time, just may keep the tire pressure monitoring level of this system to equal the tire pressure monitoring level of traditional remote tire pressure monitoring system at least when tire monitors operating.

In addition, preferably under the cycle emission mode, tire monitors operating is to launch the identical predetermined time interval of the pressure transmission signal inflation pressure of sensing tire periodically with the cycle.

Utilize this structure, just may reduce the power consumption of tire monitors operating sensing inflation pressure of tire.

Preferably, under the cycle emission mode, if tire monitors operating receives the affirmation signal of projector emission, then tire monitors operating is converted to battery saving mode with its operation from the cycle emission mode.

Utilize this structure, just may make tire monitors operating when receiving the confirmation signal, recover the hot link of pressure between tire monitors operating and the controller immediately.

Also preferably, under battery saving mode, when the variation of determined inflation pressure of tire during more than or equal to predetermined threshold, tire monitors operating is with the predetermined time interval shorter than the cycle emission mode emission pressure transmission signal that circulates.

Utilize this structure, just inflation pressure of tire may be changed in time passing to controller.

When remote tire pressure monitoring system also comprised the spare tyre monitor that is installed on the motor vehicle spare wheel tire, preferably, the spare tyre monitor so was positioned at and makes the spare tyre monitor can not receive the affirmation signal of projector emission on the vehicle.

Utilize this structure, just may avoid any false triggering of acknowledgment signal the spare tyre monitor.

In addition, the spare tyre monitor is preferably operated under macrocyclic cycle emission mode, the inflation pressure of spare tyre monitor sensing spare tyre wherein, and launch the pressure transmission signal of the information of the relevant spare tyre inflation pressure that comprises institute's sensing periodically with predetermined time interval, wherein this predetermined time interval is longer at the predetermined time interval that the emission of following cycle of emission mode in cycle comprises the pressure transmission signal of the information of relevant tire pressure than tire monitors operating.

Utilize this structure, just may monitor the inflation pressure of spare tyre reliably, suppress the power consumption of spare tyre monitor simultaneously.

Also preferably, under the cycle emission mode, if do not receive the affirmation signal from projector in the tire monitors operating predetermined time cycle, then tire monitors operating is transformed into macrocyclic cycle emission mode, the i.e. pattern of spare tyre monitor operations with its operation from the cycle emission mode.

Utilize this structure, when tire monitors operating under the cycle emission mode because emitter failures or ambient noise can not the confirmation of receipt signal time, just may reduce the emitting times of pressure transmission signal.

This remote tire pressure monitoring system also comprises the detector that travels, and it operationally links to each other with tire monitors operating and is used to detect vehicle is to travel or be in static.In this case, preferably when the detector that travels detects stationary vehicle, tire monitors operating is operated under macrocyclic cycle emission mode, it is the pattern of spare tyre operation, and the operation of forbidding tire monitors operating is transformed into battery saving mode or cycle emission mode from macrocyclic cycle emission mode, and detector detects vehicle ' up to travelling.

Utilize this structure, when vehicle does not travel, just may prevent tire monitors operating by the outer signals false triggering under battery saving mode or cycle emission mode, to operate, thereby avoid waste electric energy.

According to another kind of executive mode of the present invention, in remote tire pressure monitoring system,

The pressure transmission signal of tire monitors operating emission also comprises special code,

Receive the pressure transmission signal in response to receptor, controller produces confirmation code according to the special code that is included in the pressure transmission signal, and controls the affirmation signal that the projector emission comprises the confirmation code that is produced, and

When receiving the confirmation signal, tire monitors operating determines that according to the confirmation code that is included in the acknowledgment signal pressure transmission signal is received by the receiver.

Utilize said structure, tire monitors operating just may determine accurately under the situation of not using the vehicle identification code unique for vehicle whether the pressure transmission signal of being launched is received by the receiver.

As a result, make the reliability that on the basis that does not increase manufacturing cost, improves remote tire pressure monitoring system become possibility.

In addition, in remote tire pressure monitoring system, be included in the special code unique heading code for tire monitors operating in the pressure transmission signal.In this case, controller can produce and confirmation code whole or that the part heading code is identical.Controller also can produce heading code by using operation expression, and this expression formula has defined the definite relation between confirmation code and whole or the part special code.

In addition, but be included in special code random bit string in the pressure transmission signal.In this case, controller can produce and the identical confirmation code of a string data whole or that part is arbitrarily.Controller also can produce heading code by using operation expression, and this expression formula has defined the definite relation between confirmation code and whole or the part random bit string.

Controller also can produce as the confirmation code that is included in the error correction code of the special code in the pressure transmission signal.

In addition, in remote tire pressure monitoring system, receptor, projector and controller can be arranged on the car body all.In addition, receptor and controller can be combined into single assembly.

Description of drawings

Accompanying drawing by the following detailed description and the preferred embodiment of the present invention can better understand the present invention, yet should not limit the invention to specific embodiment, and embodiment just is used to explain.

In the accompanying drawings:

Fig. 1 is the scheme drawing of explanation according to the remote tire pressure monitoring system total of first embodiment of the invention;

Fig. 2 A is the functional block diagram of each tire monitors operating structure in the explanation remote tire pressure monitoring system shown in Figure 1;

Fig. 2 B is the functional block diagram of receiver architecture in the explanation remote tire pressure monitoring system shown in Figure 1;

Fig. 3 is the state transition diagram that each tire monitors operating changes between different operation modes in the explanation remote tire pressure monitoring system shown in Figure 1;

Fig. 4 is the diagram of circuit of explanation according to each tire monitors operating working process of working under battery saving mode of first embodiment of the invention;

Fig. 5 is the diagram of circuit of explanation according to each tire monitors operating working process of working under the cycle emission mode of first embodiment of the invention;

Fig. 6 is explanation and the diagram of circuit that carries out the receiver operation process of two way communication according to the tire monitors operating of first embodiment of the invention;

Fig. 7 A is the diagram of work of the remote tire pressure monitoring system of explanation first prior art;

Fig. 7 B is the diagram of work of explanation remote tire pressure monitoring system shown in Figure 1;

Fig. 8 A is the operating time figure of the remote tire pressure monitoring system of explanation second prior art;

Fig. 8 B is the time diagram of the operation of explanation remote tire pressure monitoring system shown in Figure 1;

Fig. 9 is the diagrammatic representation of the power consumption of each tire monitors operating in the remote tire pressure monitoring system of the remote tire pressure monitoring system more shown in Figure 1 and second prior art;

Figure 10 is the diagram of circuit of explanation according to each tire monitors operating working process of working under battery saving mode of second embodiment of the invention;

Figure 11 is the diagram of circuit of explanation according to each tire monitors operating working process of working under the cycle emission mode of second embodiment of the invention;

Figure 12 is explanation and the diagram of circuit that carries out the receiver operation process of two way communication according to the tire monitors operating of second embodiment of the invention; And

Figure 13 is the time diagram that explanation is launched the pressure transmission signal and concerned between the transmitting acknowledgement signal in response to receptor receives the pressure transmission signal.

The specific embodiment

Referring to accompanying drawing 1-13 explanation the preferred embodiments of the present invention.

It is pointed out that the same parts with identical function in the different embodiments of the invention is used identical Reference numeral in each accompanying drawing in order to be expressly understood the present invention.

" first embodiment "

Fig. 1 illustrates the total according to the remote tire pressure monitoring system S1 of first embodiment of the invention.

Remote tire pressure monitoring system S1 is installed on the vehicle 1, and is configured to the inflation pressure that monitoring is installed in four tires of 1 four wheel 5a-5d of vehicle last (i.e. preceding-right wheel 5a, preceding-left wheel 5b, back-right wheel 5c and back-left wheel 5d) respectively.

It is pointed out that vehicle 1 can have the tire of varying number.For example, vehicle 1 can have the spare tyre (not shown), thereby makes remote tire pressure monitoring system S1 be used to monitor the inflation pressure of five tires.

As shown in Figure 1, remote tire pressure monitoring system S1 comprises four tire monitors operatings 2, receptor 3, warning device 4 and four projector 8a-8d.

Each tire monitors operating 2 all is installed on of 1 four wheel 5a-5d of vehicle, be used for sensing and be installed in inflation pressure of tire on the corresponding wheel, and emission comprises the pressure transmission signal of information of the relevant inflation pressure of tire of sensing.

On the other hand, receptor 3 is installed on the car body 6 of vehicle 1, be used to receive the pressure transmission signal of tire monitors operating 2 emissions, and the information in the pressure transmission signal that receives according to being included in is determined the inflation pressure of four tires.Receptor 3 also is used for controlling projector 8a-8d and launches various signals to tire monitors operating 2, and wherein projector 8a-8d also is installed on the car body 6 of vehicle 1.For example, in response to the pressure transmission signal that receives each tire monitors operating 2 emission, the cooresponding projector 8a-8d transmitting acknowledgement signal of receptor 3 controls has received the pressure transmission signal with notice tire monitors operating 2.

Referring to Fig. 2 A, comprise sensing cell 21, battery 22, control unit 23a, transmitter/receiver unit 23b and antenna 24 on each tire monitors operating 2 function.

Sensing cell 21 disposes sensor, and for example diaphragm type pressure sensor and temperature sensor are used for exporting the sensing signal of the tire air themperature of the inflation pressure of tire of expression sensing and sensing.

Battery 22 is used to supply tire monitors operating 2 work required electric energy.

Control unit 23a has CPU, ROM, RAM and I/O device.Control unit 23a is used for carrying out predefined procedure according to the ROM program stored.In ROM, also storing unique heading code of tire monitors operating 2 in addition, thus the identity of expression tire monitors operating 2.

Particularly, control unit 23a receives the sensing signal of sensing cell 21 outputs, and determines inflation pressure of tire according to sensing signal with the predetermined time interval circulation.So control unit 23a assembles frame, it comprises the information about the unique heading code of determined inflation pressure of tire and tire monitors operating 2, and when needed this frame is provided to transmitter/receiver unit 23b.

More specifically, control unit 23a handles the sensing signal of sensing cell 21 outputs, and determines air themperature in inflation pressure of tire and the tire according to handled sensing signal with the predetermined time interval circulation.Control unit 23a can proofread and correct determined inflation pressure of tire according to air themperature in the determined tire; In this case, the inflation pressure of tire after the information representation that comprises in the frame is proofreaied and correct.Otherwise, air themperature in uncorrected inflation pressure of tire of the information representation that comprises in the frame and the tire.The process that frame is offered transmitter/receiver unit 23b is carried out according to program stored among the ROM.

In addition, control unit 23a carries out various program under the different operation modes of tire monitors operating 2, will describe the different operation modes of tire monitors operating hereinafter in detail.

Transmitter/receiver unit 23b is used to receive the frame that control unit 23a provides, and frame is modulated to the pressure transmission signal, and by antenna 24 emission pressure transmission signals; It also is used for receiving by antenna 24 signal of corresponding projector 8a-8d emission, acknowledgment signal for example, and the signal that is received is provided to control unit 23a.

Antenna 24 not only can serve as the emitting antenna of emission pressure transmission signal but also can serve as the receiving wire of the signal that receives corresponding projector 8a-8d emission.

In addition, though tire monitors operating 2 is configured to include only an antenna 24 in the present embodiment, also can comprise two antennas, one is used for emission, and another is used for receiving.

Each above-mentioned tire monitors operating 2 all is fixed among the wheel 5a-5d on corresponding one the choker relief valve, and its sensing cell 21 is arranged in the tire inboard and is exposed to the air of tire so at least.

Referring to Fig. 2 B, receptor 3 disposes receiving wire 31, receiving element 32a and control unit 32b.In addition, as Fig. 2 B and shown in Figure 1, receptor 3 is operably connected on each projector 8a-8d.

Receiving wire 31 is used to receive all pressure transmission signals of tire monitors operating 2 emissions.

Receiving element 32a is used for the pressure transmission signal that demodulation receives by receiving wire 31, and the signal after the demodulation is offered control unit 32b.

Control unit 32b disposes CPU, ROM, RAM and I/O device.Control unit 32b is used for carrying out predefined procedure according to the ROM program stored.

Particularly, the pressure transmission signal after each demodulation that provides for receiving element 32a, control unit 32b discerns the wheel that the tire monitors operating 2 of this pressure transmission signal of emission is installed in according to the heading code in the pressure transmission signal that is included in after the demodulation.

More specifically, control unit 32b is storing with reference to heading code in its RAM, its each all the heading code with a tire monitors operating 2 is identical, and relevant with this tire monitors operating 2 position on vehicle 1 (i.e. this its this tire monitors operating 2 be installed in wheel).Therefore, pressure transmission signal after each demodulation that provides for receiving element 32a, control unit 32 by coupling be included in the pressure transmission signal after the demodulation heading code be stored in RAM in one consistently discern the wheel that the tire monitors operating 2 of this pressure transmission signal of emission is installed in reference to heading code.

Pressure transmission signal after each demodulation that provides for receiving element 32a, control unit 32b also can determine that the tire monitors operating 2 with emission pressure transmission signal is installed in the inflation pressure of the tire on the same wheel according to the information in the pressure transmission signal that is included in after the demodulation.

When determined inflation pressure of tire was lower than predetermined lower bound P-low, the alerting signal of control unit 32b output expression inflation pressure of tire and position was in warning device 4.

In addition, receive the pressure transmission signal in response to receiving element 32a, among the tire monitors operating 2 corresponding emitter 8a-8d of control unit 32b control and the pressure transmission signal of this reception of emission one is so that the transmitting acknowledgement signal at every turn.Therefore, when the confirmation of receipt signal, the pressure transmission signal that can assess out tire monitors operating 2 emissions has been received device 3 and has received.

In addition, in the present embodiment, acknowledgment signal can scheduledly can be discerned by each tire monitors operating 2.

In addition, when the ignition lock of vehicle 1 rotates to when opening from closing, control unit 32b controls each projector 8a-8b emission energizing signal.This energizing signal represents to ask the request of a corresponding tire monitors operating 2 emission pressure transmission signals.In other words, this energizing signal can trigger a corresponding tire monitors operating 2 emission pressure transmission signals.

As shown in Figure 1, warning device 4 is electrically connected to receptor 3, and is arranged in the position that vehicle 1 chaufeur can be seen.Warning device 4 can be the attention display that for example disposes on vehicle 1 instrument carrier panel.In response to the alerting signal that receives from receptor 3, warning device 4 is used for the position of minimizing of driver inflation pressure of tire and tire.

Each projector 8a-8d all be installed in vehicle 1 car body 6 with four tire monitors operatings 2 on cooresponding position.More specifically, each projector 8a-8d all be positioned at a corresponding tire monitors operating 2 at a distance of a given distance.This given distance can make tire monitors operating 2 receive the signal of corresponding projector 8a-8d emission reliably.

Each projector 8a-8d is used for the various signals of emission under the control of the control unit 32b of receptor 3, comprises above-mentioned energizing signal and acknowledgment signal.

In addition,, also can be configured to comprise four antennas 31, each all corresponding tire monitors operating 2 though receptor 3 is configured to include only a receiving wire 31 in the present embodiment.In addition, each of four receiving wires 31 all is combined into one with a cooresponding projector 8a-8d.

After the integral structure of explanation remote tire pressure monitoring system S1, hereinafter its operating process will be described.

Referring to Fig. 3, in remote tire pressure monitoring system S1, each tire monitors operating 2 all has a plurality of operation modes.

Particularly, switching on replacement (POR) afterwards, shown in A among Fig. 3, the operation of each tire monitors operating 2 is transformed into various patterns, comprises macrocyclic cycle emission mode (shown in B), cycle emission mode (shown in C), battery saving mode (shown in D), triggers emission mode (shown in E) and power-down mode (shown in F).

In the operating process of each tire monitors operating 2, control unit 23a assembles a mode code in the pressure transmission signal, the current operation mode of this mode code indication tire monitors operating 2.

In the present embodiment, mode code is represented by 2 bit data.For example as shown in Figure 3, macrocyclic cycle emission mode is by " 00 " expression, and the cycle emission mode is by " 01 " expression, and battery saving mode is triggered emission mode and represented by " 10 " by " 11 " expression.

Control a cooresponding emission converted command signal among the projector 8a-8d if desired, its expression makes the order of tire monitors operating 2 from current mode transitions to another operation mode, then according to the mode code that is included in the pressure transmission signal that is received, receptor 3 is discerned the pattern of tire monitors operatings 2 current operations.

Describe the operation mode of tire monitors operating 2 below in detail.

1) macrocyclic cycle emission mode

When carrying out POR, the operation of each tire monitors operating 2 at first enters macrocyclic cycle emission mode.

Under this operation mode, each tire monitors operating 2 is all launched the pressure transmission signal periodically with long predetermined time interval (for example 1 hour).

In addition, comprise also that at vehicle 1 spare tyre and remote tire pressure monitoring system S1 comprise that also under the situation that is installed in the 5th tire monitors operating 2 on the spare tyre, the 5th tire monitors operating 2 is operated usually under macrocyclic cycle emission mode.Receptor 3 receives the pressure transmission signal of the 5th tire monitors operating 2 emissions, and the information in the pressure transmission signal that receives according to being included in is determined the inflation pressure of spare tyre.

Because spare tyre is not contained on the running vehicle wheel of vehicle 1, cause the slow variation of inflation pressure of tire so leak gas naturally.Therefore, can think that the long-time interval of macrocyclic cycle emission mode setting monitors the inflation pressure of spare tyre reliably.

Desired in addition is to avoid any interference between the pressure transmission signal of the pressure transmission signal of the 5th tire monitors operating 2 emissions and any tire monitors operating 2 emission on the wheel 5a-5d on the receptor 3.Therefore, spare tyre is preferably located on vehicle 1 car body 6, makes the 5th tire monitors operating 2 can not receive the signal of projector 8a-8d emission, thereby avoids any false triggering of the 5th tire monitors operating 2.

For example preferably, the 5th tire monitors operating 2 is far away more a lot of than the corresponding tire monitors operating on the wheel 5a-5d 2 with projector 8a-8d distance apart.Otherwise, preferably with the signal shielding of it and projector 8a-8d emission.

2) cycle emission mode

If tire monitors operating 2 receives the converted command signal from receptor 3 under macrocyclic cycle emission mode, then the operation of each tire monitors operating 2 is transformed into the cycle emission mode from macrocyclic cycle emission mode, shown in Fig. 3 center line bc.In this case, this converted command signal represents to make tire monitors operating 2 its operation to be transformed into the order of cycle emission mode from macrocyclic cycle emission mode.

In addition, each tire monitors operating 2 can be configured to and also comprises the detecting device that travels (for example acceleration pick-up), is used to detect vehicle 1 and is travelling or static.In this case, travelling if the detecting device that travels detects vehicle 1, then the operation of each tire monitors operating 2 is transformed into the cycle emission mode from macrocyclic cycle emission mode.

On the other hand, if since projector 8a-8d in a cooresponding fault or since environmental noise make tire monitors operating 2 not receive the confirmation signal, then the operation of each tire monitors operating 2 is transformed into the cycle emission mode from battery saving mode, shown in Fig. 3 center line dc.

The cycle emission mode is used for keeping when each of tire monitors operating 2 does not all have the confirmation of receipt signal tire pressure monitoring level of the S1 of system identical with legacy system at least.

At the cycle emission mode, each tire monitors operating 2 is to launch the pressure transmission signal periodically than the short predetermined time interval of macrocyclic cycle emission mode.

For example, under the cycle emission mode, predetermined time interval changes at inflation pressure of tire and was set to 15 seconds and was set to 1 minute in other situations when fast.

In addition, under the cycle emission mode, do not need for each tire monitors operating 2 with the definite inflation pressure of tire that circulates of the short time gap of time gap than emission pressure transmission signal.Therefore for power saving, in the present embodiment, under the cycle emission mode, each tire monitors operating 2 all is configured to come the cycle to determine inflation pressure of tire at the time gap identical with cycle emission pressure transmission signal.

3) battery saving mode

If tire monitors operating 2 is at the converted command signal of cycle emission mode reception from receptor 3, then the operation of each tire monitors operating 2 is transformed into battery saving mode from the cycle emission mode, shown in Fig. 3 center line cd.In this case, this converted command signal represents to make tire monitors operating 2 its operation to be transformed into the order of battery saving mode from the cycle emission mode.

If tire monitors operating 2 receives the confirmation signal at the cycle emission mode, then the operation of each tire monitors operating 2 also is transformed into battery saving mode from the cycle emission mode.More specifically, at the cycle emission mode, receptor 3 receives the pressure transmission signal of tire monitors operating 2 emissions; In response to the reception of pressure transmission signal, the corresponding projector 8a-8d of receptor 3 controls comes the transmitting acknowledgement signal; When receiving the confirmation signal, tire monitors operating 2 can conclude that the pressure transmission signal of emission thus has been received device 3 and has received; In the reception that is in response to acknowledgment signal, tire monitors operating 2 is transformed into battery saving mode with its operation from the cycle emission mode.

At battery saving mode, the variation of inflation pressure of tire and inflation pressure of tire is determined in each tire monitors operating 2 circulation.Yet 2 of each tire monitors operatings are just launched the pressure transmission signal that comprises determined inflation pressure of tire information during more than or equal to predetermined threshold in the variation of determined inflation pressure of tire.

More specifically, when inflation pressure of tire changed less than predetermined threshold, each tire monitors operating 2 stopped to launch the pressure transmission signal, thus power saving.Otherwise, when the variation of inflation pressure of tire during more than or equal to predetermined threshold, each tire monitors operating 2 is with the time gap circulation emission pressure transmission signal shorter than the time gap of cycle emission mode, for example in 1 second time gap, thereby in time the variation of inflation pressure of tire is passed to receptor 3.

4) trigger emission mode

If tire monitors operating 2 receives the energizing signal of corresponding projector 8a-8d emission under any pattern of macrocyclic cycle emission mode, cycle emission mode and battery saving mode, then the mode transitions of each tire monitors operating 2 is to triggering emission mode, shown in Fig. 3 center line be, ce and de.

In triggering emission mode, each tire monitors operating 2 is in response to the pressure transmission signal of energizing signal emission that receives; Then, its operation is converted back to last pattern from triggering emission mode, shown in line eb, ec and ed.

Being provided with and triggering emission mode is whenever can both allow its in time to receive pressure transmission signal from tire monitors operating 2 for the information that needs relevant inflation pressure of tire at receptor 3.

5) power-down mode

If tire monitors operating 2 receives the power off command signal under macrocyclic cycle emission mode or cycle emission mode, this signal indication makes the order of tire monitors operating 2 outages, then the mode transitions of each tire monitors operating 2 is to power-down mode, shown in Fig. 3 center line bf.

Before vehicle 1 transmits, the power off command signal is sent to each tire monitors operating 2 by using special device.At power-down mode, each tire monitors operating 2 stops any signal emission.

If tire monitors operating 2 receives activation signal at power-down mode, then the operation mode of each tire monitors operating 2 is transformed into macrocyclic cycle emission mode from power-down mode, shown in Fig. 3 center line fb.

Activation signal is applied to each tire monitors operating 2, is used to carry out the identification registered task as one of vehicle 1 transport process.

As mentioned above, in remote tire pressure monitoring system S1, each tire monitors operating 2 all has a plurality of operation modes, and carries out the distinctive process of this operation mode under each operation mode.

In addition, as mentioned above, also have at vehicle under the situation of spare tyre, the 5th tire monitors operating 2 that is installed on the spare tyre is operated under macrocyclic cycle emission mode usually.Yet if the 5th tire monitors operating 2 accidental converted command signals that receive from another vehicle, the operation of the 5th tire monitors operating 2 can be transformed into cycle emission mode or battery saving mode.The operation under cycle emission mode or battery saving mode of the 5th tire monitors operating 2 all is unfavorable for power saving.

Therefore, if do not receive any signal in the predetermined time cycle, comprise that each tire monitors operating 2 of the 5th tire monitors operating 2 is made its operation be transformed into macrocyclic cycle emission mode by configuration like this, shown in line cb.In addition, each tire monitors operating 2 also can comprise the detecting device that travels, and so be configured so that not to be in motoring condition if detect vehicle 1 in the detecting device predetermined time cycle of travelling, then its mode transitions is to macrocyclic cycle emission mode, shown in Fig. 3 center line cb and db.

Fig. 4 represents the process that each tire monitors operating 2 is operated under battery saving mode.The control unit 23a of each tire monitors operating 2 repeats this process.

At first in step 100, control unit 23a determines inflation pressure of tire according to the sensing signal of sensing cell 21 outputs.

In step 110, control unit 23a determines whether inflation pressure of tire changes fast.More specifically, control unit 23a determines that whether the variation (shown in Pc among Fig. 4) of inflation pressure of tire is more than or equal to predetermined threshold (shown in Pth).

In the present embodiment, inflation pressure of tire is changed in the current circulation the poor of the inflation pressure determined in the inflation pressure determined and the last circulation.On the other hand, pre-determining of threshold value considered different modes that inflation pressure changes and the precision that is included in the pressure sensor in the sensing cell 21.For example, when tyre explosion, inflation pressure of tire reduced 20kPa in 15 seconds.This threshold value is set to because the inflation pressure of tire that causes of blowing out reduces and because the intermediate value between the inflation pressure of tire minimizing that causes of gas leakage naturally.If desired, the threshold value that is provided with in this way also can change according to the precision of pressure sensor.

If the judged result in step 110 is a "No", then process is finished this circulation, and does not launch the pressure transmission signal.

Otherwise if be "Yes" in the judged result of step 110, then process advances to step 120.

In step 120, control unit 23a further determines what whether the quick variation of inflation pressure of tire was caused by the quick variation of air themperature in the tire.More specifically, control unit 23a determines that whether air temperature variations (shown in Tc among Fig. 4) is more than or equal to second predetermined threshold (shown in Tth among Fig. 4) in the tire.

In the present embodiment, in the tire air themperature be changed to the poor of the air themperature determined in the air themperature determined in the current circulation and the last circulation.

If the judged result in step 120 is a "Yes", then finish this circulation, do not launch the pressure transmission signal.

This is because in this case, according to the Boyle-Charles law, the quick variation of inflation pressure of tire is changed fast by air themperature in the tire and causes, rather than is changed fast by amount of air in the tire and to cause, for example blows out.

Otherwise,, then advance to step 130 if be "No" in the judged result of step 120.

In step 130, control unit 23a control transmitter/receiver unit 23b is by antenna 24 emission pressure transmission signals, and wherein this signal comprises the unique heading code of the information of relevant inflation pressure of tire and tire monitors operating 2.

In step 140, control unit 23a determines in the predetermined period of time Pt1 after whether transmitter/receiver unit 23b launches the pressure transmission signal the last time confirmation of receipt signal.

In the present embodiment, the value (for example 50ms) of the predetermined period of time Pt1 that determines in step 140 is set to larger than the summation of a corresponding transmitting acknowledgement signal required time (for example 20ms) among required time (for example 15ms) of each tire monitors operating 2 emission pressure transmission signal and the projector 8a-8d.

If the judged result in step 140 is a "Yes", then finish this circulation.More specifically, in this case, control unit 23a determines that according to the affirmation signal that receives the pressure transmission signal has been received device 3 and has received.

Otherwise if be "No" in the judged result of step 140, then process advances to step 150.

In step 150, control unit 23a control transmitter/receiver unit 23b launches the pressure transmission signal again.

In addition, in the present embodiment, control unit 23a comprises counting machine, is used to count the times N t that launches the pressure transmission signal again.Therefore in step 150, Nt increases by 1.

In step 160 subsequently, control unit 23a determines whether Nt equals predetermined threshold Np.

If the judged result in step 160 is a "No", then process turns back to step 140.

More specifically, in this case, in order to increase the tire that receptor 3 receives the pressure transmission signal, control unit 23a control transmitter/receiver unit 23b repeat its transmission pressure transmission signal reaches Np up to transmitter/receiver unit 23b confirmation of receipt signal or Nt.

Otherwise if be "Yes" in the judged result of step 160, then process advances to step 170, makes the operation of tire monitors operating 2 be transformed into the cycle emission mode from battery saving mode in this step.

More specifically, in this case, control unit 23a determines and can't set up conventional two way communication between tire monitors operating 2 and receptor 3 that therefore the operation with tire monitors operating 2 is transformed into the cycle emission mode from battery saving mode.

In addition, control unit 23a resets the Nt of emitting times again of pressure transmission signal when obtaining the positive result (being that the result is a "Yes") of step 140 or step 160 judgement.

Fig. 5 represents the process that each tire monitors operating 2 is operated under the cycle emission mode.The control unit 23a of each tire monitors operating 2 repeats this process.

At first in step 200, whether control unit 23a passes through predetermined period of time Pt2 after determining to launch the pressure transmission signal the last time.

This predetermined period of time Pt2 is formed in the time gap that twice is launched between the pressure transmission signal continuously under the cycle emission mode.In the present embodiment, as mentioned above, it is higher value (for example 1 minute) that predetermined period of time Pt2 is configured to when inflation pressure of tire changes slowly, is smaller value (for example 15 seconds) when variation is very fast.

In addition, though not shown in Figure 5, variation is provided with predetermined period of time Pt2 according to inflation pressure of tire by control unit 23a.

After last emission pressure transmission signal process predetermined period of time Pt2, process advances to step 210, and 23a determines inflation pressure of tire at this step control unit.

In step 220 subsequently, control unit 23a control transmitter/receiver unit 23b is by antenna 24 emission pressure transmission signals, and wherein this signal comprises the unique heading code of the information of relevant inflation pressure of tire and tire monitors operating 2.

In step 230, whether control unit 23a judges transmitter/receiver unit 23b confirmation of receipt signal.

If the definite result in step 230 is a "No", then process is got back to step 200.

Otherwise if be "Yes" in the judged result of step 230, then process advances to step 240, is transformed into battery saving mode in the operation of this step tire monitors operating 2 from the cycle emission mode.

More specifically, in this case, control unit 23a determines and can set up conventional two way communication between tire monitors operating 2 and receptor 3 that therefore the operation with tire monitors operating 2 is transformed into battery saving mode from the cycle emission mode.

Fig. 6 represents the process that receptor 3 and tire monitors operating 2 carry out two way communication.This process is carried out by the control unit 32b of receptor 3.

At first in step 310, control unit 32b determines whether the ignition lock (shown in IG among Fig. 6) of vehicle 1 is opened.

If the judged result in step 310 is a "No", in other words, if vehicle 1 does not also begin to travel, then the ignition lock of control unit 32b wait vehicle 1 is opened.

Otherwise if be "Yes" in definite result of step 310, in other words, if vehicle 1 begins to travel, then process advances to step 320.

In step 320, control unit 32b controls each projector 8a-8d emission energizing signal.

As mentioned above, the energizing signal of each projector 8a-8d emission is represented the request of the corresponding tire monitors operating 2 emission pressure transmission signals of needs.In response to the energizing signal that receives, the operation of each tire monitors operating 2 is transformed into the triggering emission mode from any of macrocyclic cycle emission mode, cycle emission mode and battery saving mode.Triggering emission mode, pressure transmission signal of each tire monitors operating 2 emission, its operation mode is converted back to last pattern from triggering emission mode then.Therefore when the pressure transmission signal that receives from tire monitors operating 2, the information in the pressure transmission signal that control unit 32b can receive according to being included in is determined the initial value of inflation pressure of tire.

In step 330, control unit 32b determines whether the pressure transmission signal of each tire monitors operating 2 emission has been received unit 32a and has received.

If the definite result in step 330 is a "No", then process directly advances to step 350.

Otherwise if be "Yes" in definite result of step 330, then process advances to step 340.

In step 340, transmitting acknowledgement signal of correspondence of control unit 32b control projector 8a-8d receives to notify each tire monitors operating 2 these pressure transmission signal to be received device 3.

In step 350, control unit 32b determines whether the ignition lock of vehicle 1 is still opened.

If the definite result in step 350 is a "Yes", in other words,, then turn back to step 330 if vehicle 1 still is in motoring condition.

Otherwise if be "No" in definite result of step 350, in other words, if vehicle 1 stops to travel, then process finishes.

Fig. 7 A and 7B have provided the operation of first traditional remote tire pressure monitoring system and jointly according to the comparison between the operation of the remote tire pressure monitoring system S1 of present embodiment, wherein in first traditional remote tire pressure monitoring system, tire monitors operating is to trigger the emission mode operation.It is pointed out that for briefly, in these accompanying drawings, only show the communication between single tire monitors operating and the receptor.

In first legacy system, shown in Fig. 7 A, be installed in that receptor on the car body serves as main device (masterdevice) and the tire monitors operating that is installed on the wheel of vehicle serves as from device (slave device).Particularly, when receptor need relevant be contained in the information of the inflation pressure of tire on the wheel, its control was installed in the projector (not shown) emission energizing signal on the car body.In response to the reception of energizing signal, the tire monitors operating emission comprises the pressure transmission signal of the information of relevant inflation pressure of tire.In addition, whether receptor is determined to be received in the predetermined period of time behind the emission energizing signal from the pressure transmission signal of tire monitors operating emission, if be not received, then control projector and launches energizing signal again.

In native system S1, shown in Fig. 7 B, tire monitors operating 2 serves as main device, and receptor 3 serves as from device.Particularly, in battery saving mode operating period, when tire monitors operating 2 determines whether to be emission pressure transmission signal, if then launch the pressure transmission signal.In response to the reception of pressure transmission signal, transmitting acknowledgement signal of correspondence of receptor 3 control projector 8a-8d.In addition, tire monitors operating 2 determines whether to be received in the predetermined period of time Pt1 after acknowledgment signal is launched the pressure transmission signal the last time, if be not received, then launches the pressure transmission signal again.

By above-mentioned comparison, can significantly find out in remote tire pressure monitoring system S1 according to present embodiment, tire monitors operating 2 can with than traditional remote tire pressure monitoring system more timely mode the information of relevant inflation pressure of tire is offered receptor 3.

Fig. 8 A and 8B have provided the operation of second traditional remote tire pressure monitoring system and jointly according to the comparison between the operation of the remote tire pressure monitoring system S1 of present embodiment, wherein in second traditional remote tire pressure monitoring system, tire monitors operating is with cycle emission mode operation.It is pointed out that for briefly, in these accompanying drawings, only show the communication between single tire monitors operating and the receptor.

In second legacy system, shown in Fig. 8 A, before reaching the quick variation of inflation pressure of tire, tire monitors operating is with long relatively time gap (for example 1 minute) cycle emission pressure transmission signal.In this stage, if receptor does not once receive the pressure transmission signal, then the link between tire monitors operating and the receptor disconnects the long-time relatively interlude cycle.

In addition, when inflation pressure of tire changes fast, tire monitors operating comes cycle emission pressure transmission signal with short relatively time gap (for example 15s), yet it is most of during the inflation pressure rapid-varying, promptly use short relatively time gap, the renewal of the information of relevant inflation pressure of tire can not be caught up with the quick variation of inflation pressure of tire in the receptor.

As a result, in second legacy system, can not between tire monitors operating and receptor, set up " the hot link of pressure ".As mentioned above, the hot link of this pressure is a kind of like this link between finger wheel tire monitor and the receptor here, during the i.e. information updating of the relevant inflation pressure of tire that obtains when tire monitors operating, the information of the relevant inflation pressure of tire of storing in the receptor is automatically updated.

Therefore, for second legacy system, can not realize real-time monitoring tyres inflation pressure.

In native system S1, shown in Fig. 8 B, tire monitors operating 2 is in battery saving mode operating period, do not launch the pressure transmission signal before changing fast reaching inflation pressure of tire.In this stage, because inflation pressure of tire does not have variation fast, so do not need to update stored in the inflation pressure of tire information in the receptor 3.Therefore, can under the situation of not launching the pressure transmission signal between tire monitors operating 2 and receptor 3 the hot link of build-up pressure.In addition, owing to do not launch the pressure transmission signal, so can save a large amount of electric energy.

In addition, because power saving, when inflation pressure of tire begins to change fast, the time gap that tire monitors operating 2 can be lacked very much (for example 1 second) circulation emission pressure transmission signal.Therefore because very short time gap, so in during inflation pressure rapid-varying major part, the renewal of the information of relevant inflation pressure of tire can be caught up with inflation pressure of tire and changed fast in the receptor 3.As a result, can keep the hot link of pressure between tire monitors operating 2 and the receptor 3.

Therefore, native system S1 almost can realize real-time monitoring tyres inflation pressure, reduces the power consumption of tire monitors operating 2 simultaneously significantly.

In addition, in the present embodiment, on the meaning that realizes real-time monitoring tyres inflation pressure, battery saving mode is called as " the hot link mode of pressure ".

Fig. 9 illustrates the experimental investigation result of power consumption of the tire monitors operating 2 of each tire monitors operating of second legacy system and native system S1.

In investigation, each tire monitors operating of second legacy system all is configured to determine periodically inflation pressure of tire with 15 seconds interval, launches the pressure transmission signal periodically with 1 minute interval.Utilize this structure, each tire monitors operating is 419mA/h in the total power consumption of specified time in the cycle.Yet 81% of total power consumption is to be used to launch the pressure transmission signal, has only 3% to be to be used for determining inflation pressure of tire.

By relatively, each tire monitors operating 2 of native system S1 all is configured to operate under battery saving mode, and wherein inflation pressure of tire is determined with the gap periods ground of 1s, and only just launches the pressure transmission signal during more than or equal to ± 5kPa in the variation of inflation pressure of tire.Utilize this structure, each tire monitors operating 2 is 176mA/h in the total power consumption of identical specified time in the cycle, and it equals 42% of each tire monitors operating total power consumption in second legacy system.In addition, in total power consumption, have only 12% to be to be used to launch the pressure transmission signal, and 61% be used for determining inflation pressure of tire.

" second embodiment "

This embodiment illustrates the operation of remote tire pressure monitoring system S1, and its operation with the first embodiment medium-long range tire air pressure monitoring system is different.

In the aforementioned embodiment, acknowledgment signal can be can be by any kind of tire monitors operating 2 identifications.In addition, when receiving the confirmation signal, each tire monitors operating 2 is not having to determine under the situation about confirming that the pressure transmission signal of being launched has been received device 3 and has received.

Yet, all use at all remote tire pressure monitoring systems under the situation of identical affirmation signal, be difficult to guarantee the reliability of these systems.Particularly, in this case, each tire monitors operating 2 of remote tire pressure monitoring system S1 can not be distinguished the affirmation signal of other projector emission on the vehicle that the affirmation signal of an emission of correspondence of projector 8a-8d and another travel near vehicle 1; Therefore, when receiving the affirmation signal of other projector emission, tire monitors operating may wrongly determine that the pressure transmission signal of emission has been received device 3 really and has received.

In order to address the above problem, a kind of method is to use vehicle identification code, and particularly, according to this method, acknowledgment signal can comprise for the unique vehicle identification code of vehicle 1; Therefore, according to the vehicle identification code in the affirmation signal that is included in reception, tire monitors operating 2 can be discerned the affirmation signal of corresponding projector 8a-8d emission, rather than the affirmation signal of other projector emissions of other vehicles.

Yet,, need to give each car to distribute unique vehicle identification code, and unique vehicle identification code of the vehicle that tire monitors operating was installed in be stored in each tire monitors operating in order to adopt said method.Can increase the quantity of Fabrication procedure so significantly, thereby increase the manufacturing cost of remote tire pressure monitoring system.

Operation according to the remote tire pressure monitoring system S1 of present embodiment can address the above problem under the situation of not using vehicle identification code.

Particularly, in the present embodiment, each tire monitors operating 2 is all launched and is comprised aforesaid pressure transmission signal for the unique heading code of tire monitors operating 2; In response to the reception of pressure transmission signal, one of the correspondence of receptor 3 control projector 8a-8d is come the transmitting acknowledgement signal, and this acknowledgment signal comprises the heading code that comprises in the pressure transmission signal that is received; When the confirmation of receipt signal, whether the heading code that each tire monitors operating 2 is all determined to be included in the affirmation signal of reception is its unique heading code, if determine that then the pressure transmission signal of being launched has been received device 3 and has received.

Figure 10 illustrates according to each tire monitors operating 2 operating process under battery saving mode according to present embodiment.The control unit 23a of each tire monitors operating 2 repeats this process.

At first in step 400, control unit 23a determines inflation pressure of tire according to the sensing signal of sensing cell 21 outputs.

In step 410, control unit 23a determines whether inflation pressure of tire changes fast.More specifically, control unit 23a determines that whether the variation (shown in Pc among Figure 10) of inflation pressure of tire is more than or equal to predetermined threshold (shown in Pth).

In the present embodiment, the account form of inflation pressure of tire variation is identical with previous embodiment.In addition, threshold value also is that mode by previous embodiment preestablishes.Therefore, omit its detailed description here.

If the definite result in step 410 is a "No", then process is finished this circulation, and does not launch the pressure transmission signal.

Otherwise if be "Yes" in definite result of step 410, then process advances to step 420.

In step 420, control unit 23a determines further whether the quick variation of inflation pressure of tire is caused by quick variation of air themperature in the tire.More specifically, control unit 23a determines that whether air temperature variations (shown in Tc among Figure 10) is more than or equal to second predetermined threshold (shown in Tth among Figure 10) in the tire.

In the present embodiment, the account form of air temperature variations is identical with previous embodiment in the tire; Therefore, omit its detailed description here.

If the definite result in step 420 is a "Yes", then process is finished this circulation, and does not launch the pressure transmission signal.

This is because in this case, according to the Boyle-Charles law, the quick variation of inflation pressure of tire is changed fast by air themperature in the tire and causes, rather than is changed fast by amount of air in the tire and to cause, for example blows out.

Otherwise if be "No" in definite result of step 420, then process advances to step 430.

In step 430, control unit 23a control transmitter/receiver unit 23b is by antenna 24 emission pressure transmission signals, and wherein this signal comprises the unique heading code of the information of relevant inflation pressure of tire and tire monitors operating 2.

In step 440, control unit 23a determines in the predetermined period of time Pt1 after whether transmitter/receiver unit 23b launches the pressure transmission signal the last time confirmation of receipt signal.

In the present embodiment, the set-up mode of the predetermined period of time Pt1 that determines in step 440 is identical with previous embodiment; Therefore, omit its detailed description here.

If the definite result in step 440 is a "No", then process advances to step 450.

In step 450, control unit 23a control transmitter/receiver unit 23b launches the pressure transmission signal again.

In addition, in the present embodiment, control unit 23a comprises counting machine, is used to count the times N t that launches the pressure transmission signal again.In step 450, Nt increases by 1.

In step 460 subsequently, control unit 23a determines whether Nt equals predetermined threshold Np.

If the definite result in step 460 is a "No", then process turns back to step 440.

More specifically, in this case, in order to increase the probability that receptor 3 receives the pressure transmission signal, control unit 23a control transmitter/receiver unit 23b repeat its transmission pressure transmission signal reaches Np up to transmitter/receiver unit 23b confirmation of receipt signal or Nt.

Otherwise if be "Yes" in definite result of step 460, then process advances to step 470, makes the operation of tire monitors operating 2 be transformed into the cycle emission mode from battery saving mode in this step.

More specifically, in this case, control unit 23a determines and can't set up conventional two way communication between tire monitors operating 2 and receptor 3 that therefore the operation with tire monitors operating 2 is transformed into the cycle emission mode from battery saving mode.

On the other hand, if be "Yes" in definite result of step 440, then process advances to step 480.

In step 480, control unit 23a extracts the heading code that is included in the confirmation of receipt signal.

In subsequent step 490, control unit 23a determines that whether the heading code extracted is the unique heading code of tire monitors operating 2 from the affirmation signal that receives.

If the definite result in step 490 is a "No", then process advances to step 450.

Otherwise if be "Yes" in definite result of step 490, then process advances to step 495.

In step 495, control unit 23a determines that the pressure transmission signal of tire monitors operating 2 emissions has been received device 3 really and has received.So finish this circulation.

In addition, control unit 23a resets the Nt of emitting times again of pressure transmission signal after obtaining the definite positive result (being that the result is a "Yes") of step 460 or step 490.

Figure 11 illustrates the process of operating according to each tire monitors operating 2 of present embodiment under the cycle emission mode.The control unit 23a of each tire monitors operating 2 repeats this process.

At first in step 500, control unit 23a determines whether pass through predetermined period of time Pt2 from last emission pressure transmission signal.

This predetermined period of time Pt2 be formed under the cycle emission mode twice continuously emission pressure transmission signal between time gap.In the present embodiment, the set-up mode of predetermined period of time Pt2 is identical with previous embodiment, therefore omits its explanation here.

Launch the last time behind the pressure transmission signal through after the predetermined period of time Pt2, process advances to step 510, and 23a determines inflation pressure of tire at this step control unit.

In step 520 subsequently, control unit 23a control transmitter/receiver unit 23b is by antenna 24 emission pressure transmission signals, and wherein this signal comprises the unique heading code of the information of relevant inflation pressure of tire and tire monitors operating 2.

In step 530, whether control unit 23a determines transmitter/receiver unit 23b confirmation of receipt signal.

If the definite result in step 530 is a "No", then process is got back to step 500.

Otherwise if be "Yes" in definite result of step 530, then process advances to step 540.

In step 540, control unit 23a extracts the heading code in the affirmation signal that is included in reception.

In subsequent step 550, control unit 23a determines that whether the heading code extracted is the unique heading code of tire monitors operating 2 from the affirmation signal that receives.

If the definite result in step 550 is a "No", then process turns back to step 500.

Otherwise if be "Yes" in definite result of step 550, then process advances to step 560.

In step 560, control unit 23a determines that the pressure transmission signal of tire monitors operating 2 emissions has been received device 3 really and has received, so the operation of tire monitors operating 2 is transformed into battery saving mode from the cycle emission mode.

Figure 12 illustrates the process of carrying out two way communication reliably according to the receptor 3 of present embodiment and tire monitors operating 2.This process is carried out by receptor 3 control unit 32b.

At first in step 610, control unit 32b determines whether the ignition lock (shown in IG among Figure 12) of vehicle 1 is opened.

If the definite result in step 610 is a "No", in other words, if vehicle 1 does not also begin to travel, then the ignition lock of control unit 32b wait vehicle 1 is opened.

Otherwise if be "Yes" in definite result of step 610, in other words, if vehicle 1 begins to travel, then process advances to step 620.

In step 620, control unit 32b controls each projector 8a-8d emission energizing signal.

As mentioned above, the energizing signal of each projector 8a-8d emission is represented the request of a corresponding tire monitors operating 2 emission pressure transmission signals of needs.In response to the reception of energizing signal, the operation of each tire monitors operating 2 is transformed into the triggering emission mode from any of macrocyclic cycle emission mode, cycle emission mode and battery saving mode.Triggering emission mode, pressure transmission signal of each tire monitors operating 2 emission, its operation mode is converted back to last pattern from triggering emission mode then.Therefore when the pressure transmission signal that receives from tire monitors operating 2, the information in the pressure transmission signal that control unit 32b can receive according to being included in is determined the initial value of inflation pressure of tire.

In step 630, control unit 32b determines whether the pressure transmission signal of each tire monitors operating 2 emission has been received unit 32a and has received.

If the definite result in step 630 is a "No", then process directly advances to step 660.

Otherwise if be "Yes" in definite result of step 630, then process advances to step 640.

In step 640, control unit 23b extracts the heading code in the pressure transmission signal that is included in reception.

In subsequent step 650, control unit 23b has made up the heading code of extracting from the pressure transmission signal that receives in acknowledgment signal, controls transmitting acknowledgement signal of correspondence of projector 8a-8d then.

In step 660, control unit 32b determines whether the ignition lock of vehicle 1 is still opened.

If the definite result in step 660 is a "Yes", in other words, if vehicle 1 still is in motoring condition, then process advances to step 630.

Otherwise if be "No" in definite result of step 660, in other words, if vehicle 1 stops to travel, then process finishes.

Figure 13 illustrates tire monitors operating 2 emission pressure transmission signals and the relation between the transmitting acknowledgement signal in response to receptor 3 receives the pressure transmission signal.

As shown in figure 13, each tire monitors operating 2 is all launched the pressure transmission signal that comprises for the unique heading code (ID sign indicating number) of tire monitors operating 2.In response to the reception of this pressure transmission signal, transmitting acknowledgement signal of correspondence of receptor 3 control projector 8a-8d, this signal comprise identical heading code in the pressure transmission signal with reception.As a result, when the confirmation of receipt signal, each tire monitors operating 2 can accurately determine with its unique heading code by the heading code in the affirmation signal that relatively is included in reception whether the pressure transmission signal of emission has been received device 3 and has received.

Therefore, by the remote tire pressure monitoring system S1 of operation, can realize the monitoring more reliable and almost real-time, and can not increase the manufacturing cost of the S1 of system the inflation pressure of tire of vehicle 1 according to present embodiment.

Though represented and above-mentioned specific embodiment of the present invention be described, implemented those skilled in the art and those skilled in the art and in not exceeding scope of the present invention, be appreciated that various distortion of the present invention, changes and improvements.

For example, as described in first embodiment, each tire monitors operating 2 also is configured to comprise the detecting device that travels (for example acceleration pick-up), and it is used for determining that vehicle 1 is to travel or be in static.In this case, when detecting vehicle 1, the detecting device that travels is in when static, each tire monitors operating 2 can be operated under macrocyclic cycle emission mode, and remains under the macrocyclic cycle emission mode operation and detect vehicle 1 up to the detecting device that travels and travel.

Utilize this structure, when remote tire pressure monitoring system S1 also comprises the 5th tire monitors operating 2 that is installed on vehicle 1 spare tyre, can suppress the 5th tire monitors operating 2 and be transformed into other any patterns from macrocyclic cycle emission mode suddenly owing to receive undesirable signal.

In the aforementioned embodiment, the variation of each inflation pressure of tire is the poor of the inflation pressure determined in the inflation pressure determined in the current circulation and the last circulation.

Yet the inflation pressure of each tire changes also can be represented by each on-cycle inflation pressure rate of change.In this case, pre-determining of threshold value needs to consider the different rate of changes of different variation patterns and the accuracy rate of pressure sensor.

In a second embodiment, each tire monitors operating 2 is all launched the pressure transmission signal, and this signal comprises for the unique heading code of tire monitors operating 2, with as special code; In response to the reception of pressure transmission signal, transmitting acknowledgement signal of correspondence of receptor 3 control projector 8a-8d, this signal comprise the heading code that the pressure transmission signal of reception comprises, with as confirmation code.When receiving the confirmation signal, whether the confirmation code that each tire monitors operating 2 is determined to be included in the affirmation signal of reception is identical with special code (being heading code) in the pressure transmission signal that is included in emission, if identical, determine that then the pressure transmission signal has been received device 3 and has received.

As the alternative embodiment of the foregoing description, receptor 3 can produce with the pressure transmission signal that is included in reception in the identical confirmation code of part special code (being heading code); Whether the confirmation code that each tire monitors operating 2 all can be determined to be included in the affirmation signal of reception is identical with part special code in the pressure transmission signal that is included in emission, if identical, determines that then the pressure transmission signal has been received device 3 and has received.

Another alternative embodiment as the foregoing description, receptor 3 can produce acknowledgment signal by using operation expression according to the special code in the pressure transmission signal that is included in reception, this expression formula is stored among the control unit 32a of the control unit 32b of receptor 3 and each tire monitors operating 2, and has defined the definite relation between whole or part special code and the acknowledgment signal; Each tire monitors operating 2 can by the confirmation code in the affirmation signal that uses this operation expression to determine to be included in reception whether with the pressure transmission signal that is included in emission in whole or the part special code is identical, if identical, determine that then the pressure transmission signal has been received device 3 and has received.

For example, receptor 3 can produce acknowledgment signal, with the error correction code as the special code in the pressure transmission signal that is included in reception.

In addition, but be included in special code random bit string in the pressure transmission signal of reception, rather than for the unique heading code of tire monitors operating 2.In other words, except the inflation pressure of tire signal with for the unique heading code of tire monitors operating 2, the pressure transmission signal can comprise the random bit string as special code.

In addition, be included in special code in the pressure transmission signal and can be included in whole or partial data in the pressure transmission signal.

In the above-described embodiments, remote tire pressure monitoring system S1 comprises four projector 8a-8d, and each is all corresponding to a tire monitors operating 2.

Yet remote tire pressure monitoring system S1 also can be configured to comprise a projector in following situation, and promptly all tire monitors operatings 2 can receive the signal of this single projector emission reliably.

This distortion, changes and improvements are all in claims restricted portion.

Claims (24)

1. remote tire pressure monitoring system comprises:

Be arranged on the tire monitors operating on the wheel of vehicle, this tire monitors operating is configured to operate under battery saving mode, wherein the tire monitors operating sensing is contained in the inflation pressure of the tire on the wheel, determine the variation of inflation pressure of tire, and only just launch the pressure transmission signal of the information of the relevant inflation pressure of tire that comprises sensing during more than or equal to predetermined threshold in the variation of determined inflation pressure of tire;

Receptor is used to receive the pressure transmission signal that tire monitors operating is launched;

Projector is used for the transmitting acknowledgement signal; And

Controller, operationally link to each other with projector with receptor, this controller is used for determining inflation pressure of tire according to the information that is included in the pressure transmission signal when receptor receives the pressure transmission signal, this controller also is used for controlling projector transmitting acknowledgement signal in response to receptor reception pressure transmission signal and has received the pressure transmission signal with notice tire monitors operating receptor

Wherein, the pressure transmission signal of tire monitors operating emission also comprises special code,

Receive the pressure transmission signal in response to receptor, controller produces confirmation code according to the special code that is included in the pressure transmission signal, and controls the affirmation signal that the projector emission comprises the confirmation code that is produced, and

When receiving the confirmation signal, tire monitors operating determines that according to the confirmation code that is included in the acknowledgment signal pressure transmission signal that sends is received by the receiver really.

2. according to the remote tire pressure monitoring system of claim 1, wherein, under battery saving mode, tire monitors operating is the air themperature in the sensing tire also, determine the variation of air themperature in the tire, and only the variation of determined inflation pressure of tire more than or equal to predetermined threshold and determined tire in the variation of air themperature just launch the pressure transmission signal during less than second predetermined threshold.

3. according to the remote tire pressure monitoring system of claim 1, wherein, under battery saving mode, if do not receive affirmation signal from projector in the predetermined period of time of tire monitors operating behind emission pressure transmission signal, then tire monitors operating is launched the pressure transmission signal again.

4. according to the remote tire pressure monitoring system of claim 3, wherein, under battery saving mode, if tire monitors operating is not received the affirmation signal from projector after launching pressure transmission signal pre-determined number again, then tire monitors operating is transformed into the cycle emission mode with its operation from battery saving mode, and tire monitors operating is with predetermined time interval cycle emission pressure transmission signal under the cycle emission mode.

5. according to the remote tire pressure monitoring system of claim 4, wherein, under the cycle emission mode, tire monitors operating comes sensing inflation pressure of tire periodically with the predetermined time interval identical with cycle emission pressure transmission signal.

6. according to the remote tire pressure monitoring system of claim 4, wherein, under the cycle emission mode, if tire monitors operating receives the affirmation signal of projector emission, then tire monitors operating is converted to battery saving mode with its operation from the cycle emission mode.

7. according to the remote tire pressure monitoring system of claim 4, wherein, under battery saving mode, when the variation of determined inflation pressure of tire during more than or equal to predetermined threshold, tire monitors operating is with the predetermined time interval shorter than the cycle emission mode emission pressure transmission signal that circulates.

8. according to the remote tire pressure monitoring system of claim 4, also comprise the spare tyre monitor that is installed on the motor vehicle spare wheel tire, wherein, this spare tyre monitor so is positioned at the affirmation signal that makes the spare tyre monitor can not receive the projector emission on the vehicle.

9. remote tire pressure monitoring system according to Claim 8, wherein, the spare tyre monitor is configured to operate under macrocyclic cycle emission mode, the inflation pressure of spare tyre monitor sensing spare tyre wherein, and launch the pressure transmission signal of the information of the relevant spare tyre inflation pressure that comprises institute's sensing periodically with predetermined time interval, wherein said predetermined time interval is longer at the predetermined time interval that the emission of following cycle of emission mode in cycle comprises the pressure transmission signal of the information of relevant inflation pressure of tire than tire monitors operating.

10. according to the remote tire pressure monitoring system of claim 9, wherein, under the cycle emission mode, if do not receive affirmation signal in the tire monitors operating predetermined time cycle from projector, then tire monitors operating is transformed into macrocyclic cycle emission mode, the i.e. pattern of spare tyre monitor operations with its operation from the cycle emission mode.

11. according to the remote tire pressure monitoring system of claim 9, also comprise the detector that travels, its operationally link to each other with tire monitors operating and be used to detect vehicle travelling or be in static,

Wherein, when the detector that travels detects stationary vehicle, tire monitors operating is operated under macrocyclic cycle emission mode, it is the pattern of spare tyre operation, and the operation of forbidding tire monitors operating is transformed into battery saving mode or cycle emission mode from macrocyclic cycle emission mode, and detector detects vehicle ' up to travelling.

12. according to the remote tire pressure monitoring system of claim 1, wherein, the special code that is included in the pressure transmission signal is a heading code unique for tire monitors operating.

13. according to the remote tire pressure monitoring system of claim 12, wherein, controller produces the confirmation code identical with heading code.

14. according to the remote tire pressure monitoring system of claim 12, wherein, controller produces the confirmation code identical with the part heading code.

15. according to the remote tire pressure monitoring system of claim 12, wherein, controller produces confirmation code by using operation expression, this expression formula has defined the definite relation between heading code and the acknowledgment signal.

16. according to the remote tire pressure monitoring system of claim 12, wherein, controller produces confirmation code by using operation expression, this expression formula has defined the definite relation between part heading code and the acknowledgment signal.

17. according to the remote tire pressure monitoring system of claim 1, wherein, the special code that is included in the pressure transmission signal is a random bit string.

18. according to the remote tire pressure monitoring system of claim 17, wherein, controller produces the confirmation code identical with random bit string.

19. according to the remote tire pressure monitoring system of claim 17, wherein, controller produces the confirmation code identical with the part random bit string.

20. according to the remote tire pressure monitoring system of claim 17, wherein, controller produces confirmation code by using operation expression, this expression formula has defined the definite relation between random bit string and the confirmation code.

21. according to the remote tire pressure monitoring system of claim 17, wherein, controller produces confirmation code by using operation expression, this expression formula has defined the definite relation between part random bit string and the confirmation code.

22. according to the remote tire pressure monitoring system of claim 1, wherein, controller produces confirmation code, with as the error correction code that is included in the special code in the pressure transmission signal.

23. according to the remote tire pressure monitoring system of claim 1, wherein, receptor, projector and controller are arranged on the car body all.

24. according to the remote tire pressure monitoring system of claim 23, wherein, receptor and controller are combined into single assembly.

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