CN200951753Y

CN200951753Y - Auto wiper system with LNT bus

Info

Publication number: CN200951753Y
Application number: CN 200520063013
Authority: CN
Inventors: 朱杰; 何翔; 夏含信
Original assignee: ChinaGPS Co Ltd Shenzhen
Current assignee: ChinaGPS Co Ltd Shenzhen
Priority date: 2005-08-09
Filing date: 2005-08-09
Publication date: 2007-09-26
Anticipated expiration: 2015-08-09

Abstract

The utility model discloses an automatic wiper system, which comprises a wiper execution portion and a rain amount detection portion. The wiper execution portion is essentially used for sending a control command to the rain amount detection portion, detecting the input switch signal of a wiper combination switch, collecting vehicle speed information, and automatically adjusting the wiping speed of the wiper. The rain amount detection portion is used for real-time detecting the amount of rain according to the control command sent by the wiper portion, and transmitting the amount information back to the wiper execution portion. The communication between the wiper execution portion and the rain amount detection portion adopts LIN bus communication technique, the wiper execution portion serves as the master node, and the rain amount detection portion serves as the slave node. The utility model adopts an electric field sensor as the rain amount detection chip to detect the electric field change on windshield glass and an MCU for detecting the voltage variation and automatically adjusting the wiping speed of the wiper according to the vehicle speed, and passive detection technique is adopted to prevent electromagnetic pollution in the vehicle.

Description

A kind of automatic wiping system with the LIN bus

Technical field

The utility model patent is a kind of automatic wiping system with the LIN bus.

Background technology

Existing windscreen wiper system mainly comes the speed of manual regulation windscreen wiper by combined switch.It has two shortcomings: the first, owing to adopt manual regulation Windshield Wiper speed, can increase the work capacity that the car owner drives, and reduced the comfort of driving; The second, can not in time tackle sewage and splash in accident on the Windshield, the sewage that drops on the Windshield can disturb car owner's sight line, and influence is driven even is caused a traffic accident.

The external automatic wiping system of producing, the initiatively photoelectric detecting technologies that adopt more.Its principle is with an infrared optical emitters, on the vehicle window that keeps out the wind, when sewage or rainwater are arranged on the Windshield, can cause the volume reflection of light to change ray cast, the photoelectron received of photelectric receiver will be less than normal value like this, thereby triggers wiper work.This rain sensor be subject to the interference of extraneous background noise, and the sensor installation difficulty is bigger because adopt detecting technique, and cost is too high, only is used for high-grade car and uses, and infrared light also can pollute the electromagnetic environment in the car simultaneously.

Summary of the invention

Technical problem to be solved in the utility model is the defective that overcomes manual wiper and infrared automatic wiping system in the prior art, and a kind of obvious automatic wiping system that has improved vehicle safety, traveling comfort and the feature of environmental protection and adopted up-to-date LIN communication network is provided.

Automatic wiping system of the present utility model comprises wiper operating part, rainfall test section.The wiper operating part mainly is responsible for to rainfall test section transmitting control commands; Detect the input switch signal of wiper combined switch; Gather the moving velocity information of automobile; The speed that scrapes of automatically regulating wiper.The rainfall test section is detected rainfall in real time according to the control command that wiper partly sends, and rainfall information is sent back the wiper operating part.LIN bus communication technology is adopted in communication between wiper operating part and the rainfall test section, and the wiper operating part is a major joint, and the rainfall test section is from node.

The wiper operating part comprises major joint MCU control part and LIN communication interface part, power supply.

The rainfall test section comprises MCU control part and rainfall detection chip, LIN communication interface part, and the rainfall detection chip is the electric field detection chip.

The invention has the beneficial effects as follows: automatic wiping system of the present invention detects electric field change on the Windshield by electric-field sensor as the rainfall detection chip, when rainwater or sewage are arranged on the Windshield, can cause near the electric field of rain sensor to change, thereby cause the output voltage of electric-field sensor to change.MCU passes through to detect these voltage varieties, the speed that scrapes of coming the automatically regulating wiper, and the present invention adopts passive detection technique, can not cause the electromagnetic pollution in the car.

Description of drawings

The utility model is described in further detail below in conjunction with the drawings and specific embodiments:

Fig. 1 is a functional block diagram of the present invention;

Fig. 2 is the circuit diagram of the wiper operating part of the specific embodiment of the invention;

Fig. 3 is the circuit diagram of the rainfall test section of the specific embodiment of the invention;

Fig. 4 is the dimension figure of electrode sensor of the present utility model.

The specific embodiment

As shown in Figure 1, windscreen wiper system comprises wiper operating part, rainfall test section, and the wiper operating part reads the sampled value of rainfall test section, and rainfall information is judged, regulates the speed that scrapes of wiper; The rainfall test section is detected rainfall in real time according to the control command that wiper partly sends, and rainfall information is sent back the wiper operating part.LIN bus communication technology is adopted in communication between wiper operating part and the rainfall test section, and the wiper operating part is a major joint, during the rainfall test section from node.

Figure 2 shows that the circuit diagram of the wiper operating part of the specific embodiment of the invention, comprising:

Power unit

The U6 of Fig. 2, C65, D28, R89, R90, R91 form the DC/DC conv, be the 12V/5V voltage transformation, and output dc voltage is stabilized in 5V ± 5%.Vdc VB exports stable 5V vdc VCC after oppositely ending protection, TVS overvoltage protection, common mode filtering.

Vdc VB exports stable 12V high-current supply VPW after oppositely ending protection, voltage clamper and noise filtering.

The U10 of Fig. 2, L3, C7, C48 form mu balanced circuit, and the VAA power supply of output offers artificial circuit part and uses.

Major joint MCU control part

The U1 of Fig. 2 is the major joint MCU control unit of automatic wiping system, totally 32 pins.It has 5 general purpose I/O port PTA ~ PTE, totally 24 I/O pins.Wherein PTA2 is as the Enable Pin of chip, and all the other I/O mouths are as the input and output control end.The PTA3 of U1, PTA4 link to each other with photoelectric isolating device U9, isolate the input that realizes the lifting glass for vehicle window control signal by photoelectricity and detect; PTB5, PTC0, PTB0, PTC1, PTA5 link to each other with P1, P2, P3, P5, the P6 of U4 respectively, communicate by the SPI serial protocol, finish functions such as house dog and data preservation; PTB1 reads the position signal of wiper swept area of wiper blade by the insulation blocking of U10 photoelectricity, is used for controlling swept area of wiper blade and stops at initial position; Input detects PTB7 as ignition signal; PTC4 links to each other with external crystal-controlled oscillation X1, as system's external clock; PTD0, PTD1 control output by the insulation blocking of U10 photoelectricity fast and at a slow speed as wiper; SPS is the incoming signal of external speed sensor, behind the SPS process photoisolator U9, carries out signal shaping through U2 then, obtains speed signal SPOUT, and wherein U2 is as op amp.SPOUT is input on the PTB6 pin of U1, and PTB6 is the timer input pin of U1, has the input capture function, can detection technique cycle of speed signal, thereby calculate the moving velocity that draws automobile by software.PTE0, PTE1, PTA2 link to each other with P4, P1, the P2 of U8 interface chip respectively, finish the level conversion of LIN communication interface; Do not use port as later ECP Extended Capabilities Port.

The U1 of Fig. 2 sends the U8 of executive command to rainfall test section among Fig. 3 as the major joint of LIN communication network, after U8 receives executive command, selects port to select four electrode work such as E1 ~ E4 by electrode.U8 obtains the corresponding magnitude of voltage of rainfall signal from the U2 of Fig. 3 rainfall test section; the voltage that changes reads in by the PTA0 of U8; through the U1 of LIN communications to Fig. 2; U1 judges the change of voltage situation; at PTB2, PTD0, PTD1 output motor control signal; U10 photoelectricity insulation blocking by Fig. 2 drives PNP aerotron Q10 and relay K 6, P type MOSFET Q19 and Q20 respectively, thus wiper intermitten fast and at a slow speed.

LIN communication interface part

Form by the U8 of Fig. 2 and R94, RL1, D13.The P1 pin of U8 links to each other with the PTE1 of U1 (serial communication SCI receiving end); the P4 pin links to each other with the PTE0 (serial communication SCI mouth sending end) of U1, and the P2 pin links to each other with the PTA2 of U1, as enabling control end; the P6 pin links to each other with power supply VPW by RL1, D13, draws protection on the realization communication level.RL1, D13 only, just need to add during as the LIN major joint at MCU.

Figure 3 shows that the circuit diagram of the rainfall measurement part of the specific embodiment of the invention, comprising:

The MCU control part

The U8 of Fig. 3 is the MCU Main Processing Unit of rainfall test section, totally 16 pins.It has 2 general purpose I/O port PTA ~ PTB, totally 14 I/O pins.Wherein PTB3 is as the Enable Pin of chip, and all the other I/O mouths are as the input and output control end; The PTA0 of U8 links to each other with the P36 pin of the P8 of J3, U2, imports as the rainfall signal; PTA1, PTB2, PTB3 link to each other with P1, P4, the P2 pin of U1 respectively, the input and output of the P6 pin LIN of control U1; PTA5 meets external crystal-controlled oscillation X2; PTB0, PTB1 link to each other with P34, the P33 pin of U3 respectively, select control output as electrode; Do not use port as later ECP Extended Capabilities Port.

The rainfall detection chip

The U2 of Fig. 3 is the rainfall detection chip, and the P4 pin of U2 is connected with the P4 pin of J2, as electrode screening protection end; The P8-P11 pin is connected with the P3-P6 pin of J2 respectively, imports as electrode signal; P33, P34 pin are connected with PTB0, the PTB1 of U8 respectively, as E1 ~ E4 electrode selecting side; The P36 pin links to each other with the PTA0 of U8, as the rainfall signal output part; Do not use port as later ECP Extended Capabilities Port.

Four electrode E1-E4 represent with WVS1-WVS4, are connected on four purpose made copper sheets, and this copper sheet is adhered to the inboard of windshield.Along with the size variation of outside rainfall, respective change also will take place in the magnitude of current on the electrode, thereby be reflected in the change of voltage of the signal output part of U2.U8 by the size of judging voltage signal control major joint and back windscreen wiper from the wiper motor of node fast, at a slow speed, intermittent moment.Provide convenience and prevent for manual regulation windscreen wiper speed simultaneously and the malfunctioning part that brings inconvenience of automatic wiping system the manual manipulation wiper still is installed at bridge column.

LIN communication interface part

U1 and RW1 by Fig. 3 form.The P1 pin of U1 links to each other with the PTA1 of U8 (serial communication SCI receiving end), and the P4 pin links to each other with the PTB2 (serial communication SCI mouth sending end) of U8, and the P2 pin links to each other with the PTB3 of U8, and as enabling control end, the P6 pin links to each other with the P6 pin of U8 (the 1st chapter).The ENL of P2 pin finishes the chip enable function.

Fig. 4 a is depicted as the Facad structure scheme drawing of electrode sensor, and Fig. 4 b is the scheme drawing at the electrode sensor back side.

Electrode sensor partly is attached to the inboard of Windshield, and link together with the electrode tip E1-E4 of rainfall detection chip, be responsible for detecting the variation of external electrical field, the specific inductance capacity of the size of electrode sensor, shape, material all will influence the sensitivity that rainfall detects.Produce in enormous quantities for the ease of product, this product selects for use circuit printing plate to make electrode sensor, and electrode is made as shown in the figure double-sided circuit printed panel, and electrode shape adopts wedge shape, the area of left side electrode can increase the sensitivity that detects like this greater than the electrode on the right.The identical shop copper of area is adopted at the back side of printed panel, and is connected in the SHIELD of rainfall detection chip end, plays shielding car internal electric field and disturbs.

Claims

1. automatic wiping system with the LIN bus, comprise the wiper operating part, the rainfall test section, described wiper operating part reads the sampled value of rainfall test section, and rainfall information judged, regulate the speed that scrapes of wiper, described rainfall test section is detected rainfall in real time according to the control command that wiper partly sends, and rainfall information sent back the wiper operating part, it is characterized in that: LIN bus communication technology is adopted in the communication between described wiper operating part and the rainfall test section, the wiper operating part is a major joint, and the rainfall test section is from node.

2. the automatic wiping system of band LIN bus as claimed in claim 1, it is characterized in that: described wiper operating part comprises major joint MCU control part and LIN communication interface part, power supply, and described rainfall test section comprises MCU control part and rainfall detection chip, LIN communication interface part.

3. the automatic wiping system of band LIN bus as claimed in claim 2, it is characterized in that: described rainfall detection chip is the electric field detection chip.