CN201002483Y

CN201002483Y - Tyre pressure monitoring system based on K line communication

Info

Publication number: CN201002483Y
Application number: CNU2006200164375U
Authority: CN
Inventors: 朱昌荣; 金铃淇; 张骁
Original assignee: ChinaGPS Co Ltd Shenzhen
Current assignee: ChinaGPS Co Ltd Shenzhen
Priority date: 2006-12-12
Filing date: 2006-12-12
Publication date: 2008-01-09
Anticipated expiration: 2016-12-12

Abstract

The utility model refers to a tire pressure monitoring system, which includes a pressure sensor module used to monitor the tire pressure as well as a master control unit used to communicate with the pressure sensor module in wireless transmission mode. The master control unit is connected to a CAN bus of the vehicle by a K-line diagnostic communication and communicates with a central control system. The utility model tire pressure monitoring system is integrated into the control system of the vehicle and communicates with an electronic component control system of the vehicle, which has no data communication disturbance and is high in reliability. On one hand the data can be stored in favor of the analysis processing to an accident and carrying out the display alarm, on the other hand the accident of the vehicle caused by the tire breakdown can be avoided through the central control system by controlling the electronic stabilization system and the electronic brake-force distribution system. Meanwhile a rear lamp gives an alarm to other vehicles to decrease the traffic accident, which facilities the operation and is strong in practicability.

Description

System for monitoring pressure in tyre based on the communication of K line

Technical field

The utility model relates to system for monitoring pressure in tyre, more particularly, relates to a kind of system for monitoring pressure in tyre based on the communication of K line.

Background technology

The system for monitoring pressure in tyre of prior art (tyre pressure monitoring system is called for short TPMS) generally includes at least one tire pressure sensor, tire pressure receiving element and tire pressure display unit at present.The tire pressure monitoring system of prior art is that to utilize what be installed in that each takes turns tyre cavity be the air pressure that the pressure sensor of power supply is directly measured tire with the lithium ion battery, and by wireless-modulated tire pressure is transmitted directly to and is installed on the receiver in the operator's compartment, that have the wireless receiving function, be transferred on the telltale again.Telltale shows each tire pressure at any time, and the driver can understand the air pressure situation of each tire intuitively, and during too low or seepage, system will auto alarm when tire pressure.But the shortcoming of this type of tire pressure monitoring system is, need be provided with one independently, has the receptor and the telltale of wireless receiving function, thereby takies cab space, is unfavorable for the integration of bridge equipment and attractive in appearance.

The utility model content

The technical problems to be solved in the utility model is that the above-mentioned defective at prior art provides a kind of system for monitoring pressure in tyre.

The technical scheme that its technical matters that solves the utility model adopts is: construct a kind of system for monitoring pressure in tyre, comprise: the pressure sensor module that is used to monitor tire pressure, the main control unit that carries out communication with wireless communication mode with described pressure sensor module, described main control unit is connected on the CAN bus of automobile by the communication of K radiodiagnosis x, carry out communication with master control system, described main control unit comprises: the radiofrequency receiving chip that is used to receive the data that described pressure sensor module sends, read the microprocessor of rf data, send the low frequencies module of data to described pressure sensor module, PMU and described main control unit is connected to K line communication module on the CAN bus of automobile.

In system for monitoring pressure in tyre described in the utility model, described pressure sensor module transmits data with the 315MHz radio-frequency communication to described main control unit, and described main control unit transmits data with the 125KHz low frequency communication to described pressure sensor module.Described CAN bus communication medium is twisted-pair feeder, coaxial cable or light transmitting fiber.Described radiofrequency receiving chip is worked under 315MHz, FSK pattern.Described radiofrequency receiving chip is connected by the SPI module with described microprocessor.

Implement system for monitoring pressure in tyre of the present utility model, have following beneficial effect: system for monitoring pressure in tyre is integrated in the control system of automobile, carry out communication with the electronic component control system of automobile, there is not the interference of data communication, the reliability height, can be convenient to the analyzing and processing of accident and carry out display alarm by storage data on the one hand, pass through the electric stabilizing system and the EBD (Electric Brakeforce Distribution) of master control system Control of Automobile on the other hand, prevent that automobile from accident occurring because of tire fault, also report to the police to other vehicles simultaneously by the automobile back light, reduce the generation of traffic accident, therefore made things convenient for user's operation, practical.

Description of drawings

The utility model is described in further detail below in conjunction with drawings and Examples, in the accompanying drawing:

Fig. 1 is the structured flowchart of the utility model system for monitoring pressure in tyre;

Fig. 2 is the workflow diagram of the utility model main control unit;

Fig. 3 is that the utility model adopts SCI serial communication interface circuit figure.

The specific embodiment

As shown in Figure 1, in system for monitoring pressure in tyre of the present utility model, comprise: the pressure sensor module 1 that is used to monitor tire pressure, also comprise: the main control unit 2 that carries out communication with radio frequency or other wireless communication modes with pressure sensor module 1, this main control unit 2 is connected on the CAN bus of automobile by the communication of K radiodiagnosis x, carry out communication with master control system 3, main control unit comprises the radiofrequency receiving chip 21 that is used to receive the data that described pressure sensor module 1 sends, read the microprocessor 22 of rf data, send the low frequencies module 24 of data to pressure sensor module 1, PMU 23 and main control unit 2 is connected to K line communication module 25 on the CAN bus of automobile.

As shown in Figure 2, described main control unit 2 passes through K line communications protocol to master control system 3 transmission information.The software agent of main control unit 2 is circulations that a circulation receives processing data, and timer overflows the receiving course that interruption will interrupt non-partial data, and will come back to after the initialization of related data state in this circulation.Radiofrequency receiving chip 21 is worked under 315MHz, FSK (frequency shift keyed abbreviation) pattern.Microprocessor 22 is connected by the SPI module with radiofrequency receiving chip 21.Radiofrequency receiving chip 21 is behind the rf data of MANCHESTER (Manchester) coding that receives the pressure sensor transmission, and the serial data that is translated into Transistor-Transistor Logic level is exported from the MOSI mouth, and exports clock synchronously on the SCLK mouth.Microprocessor just can read rf data exactly by clock signal like this.The speed of data transmission is 9600 baud rates under the FSK pattern, in order to reject spurious signal, read data each the time, all the opening timing device overflows the deficiency of data of interrupting guaranteeing elimination, and begin to wait for Frame next time, after each Frame receives, microprocessor 22 all want calculation check and, with the verification that receives with compare, thereby judge whether this secondary data hardwood is correct.Simultaneously data are communicated by letter by the K radiodiagnosis x, be transferred to automobile master control system 3.Master control system 3 is reminded the driver by instrument, carries out Intelligent treatment in conjunction with the electric stabilizing system (ESP) and the EBD (Electric Brakeforce Distribution) (EBD) of vehicle simultaneously.

Physical interface circuit as shown in Figure 3, requirement according to KWP2000 serial communication protocol Physical layer, it is the input of data that the communication of all information is flowed, output is all carried out on the K bus, therefore adopts the SCI serial communication interface to carry out asynchronous serial communication. and the MC33290 special chip of selecting for use motorola inc to produce is realized the TTL conversion between serial interface SCI and K bus.MC33290 is a series connection bus interface device, and it provides the communication interface of bi-directional half-duplex for the diagnostic servicing of automotive field, is to aim at microcontroller among the ECU through communicating by letter and the design-calculated interface chip between ISO K line and upper platform.

Claims

1, a kind of system for monitoring pressure in tyre, comprise: the pressure sensor module (1) that is used to monitor tire pressure, it is characterized in that, also comprise: the main control unit (2) that carries out communication with wireless communication mode with described pressure sensor module (1), described main control unit (2) is connected on the CAN bus of automobile by the communication of K radiodiagnosis x, carry out communication with master control system (3), described main control unit (2) comprising: be used to receive the radiofrequency receiving chip (21) that described pressure sensor module (1) sends data, read the microprocessor (22) of rf data, send the low frequencies module (24) of data and described main control unit (2) is coupled to K line communication module (25) on the CAN bus of automobile to described pressure sensor module (1).

2, system for monitoring pressure in tyre according to claim 1, it is characterized in that, described pressure sensor module (1) transmits data with the 315MHz radio-frequency communication to described main control unit (2), and described main control unit (2) transmits data with the 125KHz low frequency communication to described pressure sensor module (1).

3, system for monitoring pressure in tyre according to claim 1 is characterized in that, described CAN bus communication medium is twisted-pair feeder, coaxial cable or light transmitting fiber.

4, system for monitoring pressure in tyre according to claim 1 is characterized in that, described radiofrequency receiving chip (21) is worked under 315MHz, FSK pattern.

5, system for monitoring pressure in tyre according to claim 1 is characterized in that, described radiofrequency receiving chip (21) is connected by the SPI module with described microprocessor (22).