Patent Application
20110254660
1. Field of the Invention
The present invention relates to a tire pressure monitoring method, especially to integrated system and method for tire pressure monitoring and remote keyless entry.
2. Description of Prior Art
When the pneumatic pressure within a tire of vehicle (referred as tire pressure in the following) is abnormal, there are several disadvantages. For example, tire service life decreases and fuel consumption increases. Moreover, brake effect is affected and the possibility of tires going flat also increases to cause car accident. Therefore, a tire pressure monitor system (referred as TPMS in the following) is gradually applied in vehicles to assure driving safety and to effectively avoid car accidents caused by driving a vehicle having abnormal tire pressures. A prior art tire pressure monitor system comprises a tire pressure sensor and a radio frequency (RF) transceiver (together referred to as tire pressure monitoring module) installed in the tire, and an RF transceiver and a display installed in a vehicle. The tire pressure monitoring module measures tire pressure data of a corresponding tire, then wirelessly transmits the tire pressure data to the RF transceiver in vehicle to show the tire pressure data on display for the vehicle user.
Moreover, keyless entry system has been widely used for vehicle to replace traditional physical key. The keyless entry system can be classified to Remote Keyless Entry (RKE) system and Passive Keyless Entry (PKE) system. In RKE system, user needs to press the RKE fob to unlock the vehicle; while in the PKE system, the vehicle is automatically unlocked when the PKE fob is close enough to the vehicle. Namely, the PKE user does not need to press the PKE fob to unlock his vehicle. In the above mentioned two keyless entry systems, the key fob has wireless transmitter and the vehicle has corresponding wireless receiver.
The above mentioned tire pressure monitoring system and the keyless entry system are two independent systems for vehicle and do not communicate to each other or have shared component. More particularly, the vehicle needs one set of wireless receiver corresponding to the tire pressure monitoring system, and another set of wireless receiver corresponding to the keyless entry system. However, if the tire pressure monitoring system and the keyless entry system exploit the same frequency band, cost can not be reduced because hardware is not shared in above mentioned prior art systems.
Moreover, the tire pressure monitoring module of the conventional tire pressure monitoring system is located within the vehicle tire and is powered by battery. The signal transmitting period (namely the temporal duration between two wireless tire pressure signals sent by the tire pressure monitoring module) is desirably long enough to save battery power. However, for safety concern, the vehicle user should be informed the tire pressure in time. The tire pressure monitoring module is also desirably to provide tire pressure data to vehicle user as the user intends to drive the vehicle.
It is an object of the present invention to provide an integrated system and method for tire pressure monitoring and remote keyless entry in order to provide tire pressure data in time.
It is another object of the present invention to provide an integrated system and method for tire pressure monitoring and remote keyless entry for satisfying the real time requirement of tire pressure data and the requirement of saving power.
Accordingly, the integrated system for tire pressure monitoring and remote keyless entry comprises an in-vehicle integrated controller located within the vehicle and comprising a central controller unit and a central wireless transceiver electrically connected to the central controller unit; and at least one tire pressure monitoring module located at a vehicle tire. The tire pressure monitoring module comprises a tire pressure processing unit, a tire pressure wireless transceiver and a tire pressure sensor, wherein the pressure processing unit is electrically connected to the tire pressure wireless transceiver and the tire pressure sensor, the tire pressure wireless transceiver is operated at the predetermined carrier frequency. The in-vehicle integrated controller is configured to send a tire information request signal to the tire pressure monitoring module when the in-vehicle integrated controller receives and authenticates an unlocked request from the key fob. The tire pressure monitoring module is configured to send a tire information signal containing at least tire pressure data within a predetermined time threshold after the tire pressure monitoring module receives the tire information request signal.
Accordingly, the integrated method for tire pressure monitoring and remote keyless entry comprises following steps:
(a) sensing an unlocked request from the key fob when the vehicle is locked;
(b) sending a tire information request signal to a tire pressure monitoring module when an ID code in the unlocked request is authenticated; and
(c) the tire pressure monitoring module sending a tire information signal containing at least a tire pressure data within a predetermined time threshold after the tire pressure monitoring module receives the tire information request signal, wherein the tire information signal is sent at the predetermined carrier frequency.
By the system and method of the present invention, the vehicle needs only one a wireless transceiver therein for the tire pressure monitoring system and remote keyless entry system, the cost is reduced. Moreover, the tire pressure monitoring module sends tire pressure data within a predetermined time threshold (for example, 6 seconds) after the vehicle is unlocked. The demand for enhanced safety is achieved.
The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself, however, may be best understood by reference to the following detailed description of the invention, which describes an exemplary embodiment of the invention, taken in conjunction with the accompanying drawings, in which:
The tire pressure monitoring module 20 comprises a tire pressure processing unit 200, a tire pressure wireless receiver 210a, a tire pressure wireless transmitter 210b, and a tire pressure antenna (not shown), where tire pressure wireless receiver 210a and the tire pressure wireless transmitter 210b have wireless communication with the central wireless transceiver 110, and can be integrated into a tire pressure wireless transceiver 210. The tire pressure monitoring module 20 is, for example, a battery-powered tire pressure monitoring module and further comprises a tire pressure sensor 220 and a power source (such as a battery) 230. The power source 230 also provides electrical power to other components in the tire pressure monitoring module 20. The tire pressure sensor 220 is electrically connected to tire pressure processing unit 200 to send a measured tire pressure data to the tire pressure processing unit 200. The tire pressure processing unit 200 is programmed to process the measured tire pressure data and generate the tire pressure signal applicable for the tire pressure wireless transceiver 210. The programming for the tire pressure processing unit 200 is known to the skilled in the art and is not detailed here. The tire pressure processing unit 200 also receives control command sent from the central controller unit 100 and received through the tire pressure wireless transceiver 210 to control the transmitting period of the tire information signal, which will be detailed later. The tire pressure monitoring module 20 also comprises other sensors such as temperature sensor (not shown) or power sensor (not shown) to sense a temperature in the tire and a remained battery power.
When the vehicle is not at operation (such as before ignition), the tire pressure monitoring module 20 sends tire information signal to the in-vehicle integrated controller 10 at a longer standby period, where the tire information includes at least one of tire pressure data, tire temperature data and battery power data. After the tire pressure monitoring module 20 receives a tire information request signal sent from the in-vehicle integrated controller 10, the tire pressure monitoring module 20 sends tire information signal to the in-vehicle integrated controller 10 within a predetermined time threshold. The predetermined time threshold is, for example, 6 seconds. The tire information signal is sent at high frequency carrier (such as 433.92 MHz or 315 MHz). According to a preferred embodiment of the present invention, the tire information signal at this time comprises at least one tire pressure data. The tire pressure monitoring module 20 sends tire information signal to the in-vehicle integrated controller 10 at a shorter operation period after the vehicle is at operation (such as after ignition), where the tire information includes at least one of tire pressure data, tire temperature data and battery power data.
After the vehicle is unlocked, the in-vehicle integrated controller 10 sends a tire information request signal to the tire pressure monitoring module 20 to ask the tire pressure monitoring module 20 to send tire information instantly (S114). The tire pressure monitoring module 20 will send the tire information signal containing a tire information (having at least a tire pressure data) within a predetermined time threshold (for example, 6 seconds) to the in-vehicle integrated controller 10. The tire information is stored in the in-vehicle integrated controller 10 or shown on a display (not shown) under the control of the in-vehicle integrated controller 10. When the in-vehicle integrated controller 10 judges that the vehicle is ignited in step S120, the in-vehicle integrated controller 10 sends a period changing signal to the pressure monitoring module 20 to change the signal-transmitting period for the pressure monitoring module 20 (S122).
Refer again to
If the in-vehicle integrated controller 10 receives a locked command from the key fob 30 at step S140, it means the vehicle user might be away from vehicle or the vehicle is not in operation, the operation state of the in-vehicle integrated controller 10 returns to the initial locked state (S100) and waits for the unlocked command from the key fob 30.
To sum up, the integrated system and method for tire pressure monitoring and remote keyless entry have following advantages:
1. The vehicle needs only one in-vehicle wireless transceiver for operation with the tire pressure monitoring system and remote keyless entry system, the cost is reduced.
2. After the vehicle door is unlocked by the remote keyless entry system, a tire information request is sent to the tire pressure monitoring module of the tire pressure monitoring system. The tire pressure monitoring module sends a tire information signal (containing at least the tire pressure data) within a predetermined time threshold (for example 6 seconds). Therefore, vehicle user can be informed of the tire pressure before he actually drives the vehicle and the safety standard is enhanced.
3. The tire pressure monitoring module sends a tire information signal at a longer period before the vehicle is ignited, and the tire pressure monitoring module sends a tire information signal at a shorted period after the vehicle is ignited, both safety and power-saving requirements can be achieved.
As the skilled person will appreciate, various changes and modifications can be made to the described embodiments. It is intended to include all such variations, modifications and equivalents which fall within the scope of the invention, as defined in the accompanying claims.
