The utility model content
The purpose of the utility model provides a kind of modulus formula vacuum servo system that control is simple and convenient, reliability is high that is applied to electronlmobil.
For realizing above-mentioned purpose; The utility model provides a kind of modulus formula electric vacuum booster system; Comprise by master brake cylinder band vacuum booster assembly, brake vacuum pipe, brake vacuum uniguide; Vacuum pump; The sealed gas chamber that storage tank constitutes, said master brake cylinder band vacuum booster assembly links to each other with storage tank through the brake vacuum pipe, and said storage tank links to each other with said vacuum pump through the brake vacuum uniguide; This modulus formula electric vacuum booster system also comprises vacuum pressure sensor and vacuum servo system controller; Said vacuum pressure sensor links to each other with the brake vacuum pipe of said sealed gas chamber, is used to detect the pressure in the sealed gas chamber and pressure signal converted to voltage analog signal and be transferred to said vacuum servo system controller, and said vacuum servo system controller links to each other with said vacuum pressure sensor with said vacuum pump; Be used for the voltage analog signal that vacuum pressure sensor transmission comes is converted into digital signal, and digital signal handled control vacuum pump and in limiting the draught head scope, work.
This modulus formula electric vacuum booster system converts voltage analog signal to through the pressure in the vacuum pressure sensor detection sealed gas chamber and with pressure signal; And utilize the vacuum servo system controller that the voltage analog signal of vacuum pressure sensor output is converted into digital signal; And then the control vacuum pump is worked in limiting the draught head scope; Adopt digital signal to make the reliability of system high, antijamming capability is strong.
The vacuum servo system controller comprises control chip; A/D converter, relay, aerotron and interface socket; Said vacuum servo system controller links to each other with external source, vacuum pressure sensor and vacuum pump through interface socket; The voltage signal of said vacuum pressure sensor converts digital signal to and is transferred to control chip through A/D converter, control chip control relay and aerotron work, and then make vacuum pump work and stop.
The high pressure port of vacuum pressure sensor is exposed in the atmosphere, and low-pressure port links to each other with sealed gas chamber, and it becomes the difference of pressure signal transition of 0~100KPaD the voltage signal of 0.5~4.5V.
The air pressure of the sealed gas chamber of vacuum servo system and the scope of atmospheric difference of pressure are 50KPaD~75KPaD.
A/D converter is 128 ~ 179 with the scope of the digital signal that the voltage analog signal of 2.5~3.5V converts to.
The beneficial effect that the utlity model has:
The modulus formula electric vacuum booster system of the utility model converts voltage analog signal to through the pressure in the vacuum pressure sensor detection sealed gas chamber and with pressure signal; And utilize the vacuum servo system controller that the voltage analog signal of vacuum pressure sensor output is converted into digital signal; And then the control vacuum pump is worked in limiting the draught head scope; Adopt digital signal to make the reliability of system high, antijamming capability is strong.
The specific embodiment
For the purpose that makes the utility model, technical scheme, and advantage clearer, below with reference to accompanying drawing to the utility model further explain.
Fig. 1, Fig. 2 are the pressure system of the utility model modulus formula electric vacuum booster system and the structural representation of electric system; Visible from figure, this modulus formula electric vacuum booster system comprises by master brake cylinder band vacuum booster assembly 1; Brake vacuum pipe 2; Brake vacuum uniguide 5, vacuum pump 6, the sealed gas chamber that storage tank 4 constitutes; Said master brake cylinder band vacuum booster assembly 1 links to each other with storage tank 4 through brake vacuum pipe 2; Said storage tank 4 links to each other with said vacuum pump 6 through brake vacuum uniguide 5, also comprises vacuum pressure sensor 3 and vacuum servo system controller 8, and said vacuum pressure sensor 3 links to each other with the brake vacuum pipe 2 of said sealed gas chamber; Be used to detect the pressure in the sealed gas chamber and pressure signal converted to voltage analog signal and be transferred to said vacuum servo system controller 8; Said vacuum servo system controller 8 links to each other with said vacuum pressure sensor 3 with said vacuum pump 6, is used for the voltage analog signal that vacuum pressure sensor 3 transmission comes is converted into digital signal, and digital signal is handled control vacuum pump and in limiting the draught head scope, work.
Visible from above description, pressure system mainly is made up of master brake cylinder band vacuum booster assembly, vacuum pump, storage tank, its essence is to constitute a fully enclosed air chamber.With the air extraction of sealed gas chamber, it is the sealed gas chamber of negative pressure that sealed gas chamber is appeared with respect to barometric pressure during vacuum pump work.At the brake system glancing impact, to the braking force of brake pedal acting: F=F1+ △ p*s, wherein, F1 is that chaufeur is stepped on the used power of brake pedal; △ p*s is making a concerted effort of atmosphere and sealed gas chamber pressure; F is the antagonistic force of hydraulic braking system, and when the power F of needs one timing, if there is △ p*s to exist, then F1 can reduce, and plays the effect of brake boost thus.
Electric system is made up of vacuum pump 6, vacuum pressure sensor 3, vacuum servo system controller 8; Wherein, Vacuum servo system controller 8 links to each other with vacuum pressure sensor 3 with vacuum pump 6 respectively; Its essence is that constituting a control vacuum pump bleeds and keep in the certain negative pressure value scope of air chamber air pressure, in this embodiment, the air pressure of the sealed gas chamber of vacuum servo system and the scope of atmospheric difference of pressure are 50KPaD~75KPaD.
Fig. 3 is the structural representation of vacuum pressure sensor; Visible from figure; The high pressure port of vacuum pressure sensor is exposed in the atmosphere; Low-pressure port inserts the airtight vacuum air chamber, and electrical apparatus interface is connected with the vacuum servo system controller, and it converts air pressure in the sealed gas chamber and atmospheric difference of pressure into voltage analog signal; Specifically be the voltage analog signal that the difference of pressure signal transition of 0~100KPaD is become 0.5~4.5V, the formula when conversion is: U=(0.8 (P1-P2)+10) % * Vcc.Wherein, P1 is a barometric pressure, and P2 is the vacuum chamber internal gas pressure, Vcc=5V.
Visible by Fig. 2 and Fig. 4, vacuum servo system controller 8 links to each other with vacuum pump 6 with key switch control power supply 7, vacuum pressure sensor 3 through interface socket 18.The 8-1 stitch of interface socket 18 links to each other with the positive pole of key switch control power supply 7; One end of vacuum pump 6 links to each other with the negative pole of key switch control power supply 7, and the other end links to each other with the 8-3 stitch of interface socket 18; The positive source port of pressure sensor 3 links to each other with the 8-2 stitch of interface socket 18; The power cathode port of pressure sensor 3 links to each other with the 8-5 stitch of interface socket 18 or 8-6 stitch, and the signal output port of pressure sensor 3 links to each other with the 8-8 stitch of interface socket 18.
Fig. 4 is the internal circuit schematic diagram of vacuum servo system controller; Visible from figure, vacuum servo system controller 8 comprises inductance 11, control chip 12, A/D converter 13 (12V/5V), nonpolar electric capacity 14, polar capacitor 15, resistance 16, diode 17, interface socket 18, relay 19 and aerotron 20.Wherein, the V of control chip 12
CCPort links to each other with an end of inductance 11; The other end of inductance 11 connects the 5V forward voltage; The input port Vin of A/D converter 13 links to each other with resistance 16 through series diode 17 with the 8-4 stitch of interface socket 18; This input port Vin links to each other with an end of nonpolar electric capacity 14 and polar capacitor 15, the other end ground connection of nonpolar electric capacity 14 and polar capacitor 15, and the PF2 port of control chip 12 links to each other with the base stage of aerotron 20; The grounded emitter of aerotron 20; The collecting electrode of aerotron 20 is connected with diode D3, and the two ends of the coil of relay 19 input circuits are connected with the corresponding port of diode D3 respectively, and relay 19 output loops link to each other with the 8-3 stitch with the 8-1 stitch of interface socket 18.The voltage analog signal that the vacuum pressure sensor transmission comes converts digital signal to and is transferred to control chip 12 through the A/D converter 13 of vacuum servo system controller; Control chip 12 control relays 19 and aerotron 20 work, and then make vacuum pump work and stop.In this embodiment, A/D converter is 128 ~ 179 with the scope that the voltage signal of 2.5~3.5V converts digital signal into.
In the preferred implementation in the utility model, the interface socket of vacuum servo system controller is the socket with 9 stitch.Concrete stitch connects: the 8-1 stitch is a key switch, and its voltage is 12V; The 8-2 stitch connects the positive source port pin of pressure sensor; The 8-3 stitch is that vacuum pump is just being supplied power; The 8-4 stitch is a key switch; The 8-5 stitch is the 12V negative electricity, connects the power cathode port of pressure sensor; The 8-6 stitch is the 12V negative electricity; 8-7 stitch key switch ON (reservation); The 8-8 stitch connects the signal input port of pressure sensor; The 8-9 stitch is vacuum pump power supply just (reservation), and wherein, 8-4 stitch and 8-6 stitch are power supply of this controller and ground wire, and 8-1 stitch and 8-3 stitch are built-in relay node two ends.
Utilize the modulus formula electric vacuum booster system of the utility model to carry out the method that air pressure is controlled, form by following steps:
S1: modulus formula electric vacuum booster system works on power;
S2: vacuum pressure sensor detects the air pressure and the atmospheric difference of pressure of sealed gas chamber, and converts difference of pressure into voltage analog signal;
S3: the vacuum servo system controller receives the voltage analog signal of vacuum pressure sensor; A/D converter in it converts voltage analog signal digital signal to and is transferred to control chip; Control chip is according to its height to the drive level of the transistor base of vacuum servo system controller of size adjustment of digital signal; Make aerotron realize emitter and collector conducting channel conducting or end; Thereby the driving relay coil is switched on or switched off relay, control vacuum pump work or stop.
When the air pressure of the sealed gas chamber of vacuum force aid system and atmospheric difference of pressure during less than 50KPaD; The voltage analog signal of vacuum pressure sensor is less than 2.5V, and the A/D converter of vacuum servo system controller is lower than 128 with the digital signal that voltage analog signal converts to, and control chip is a high level to the drive level of transistor base; Make transistor emitter and the conducting of collecting electrode conducting channel; Thereby the driving relay coil makes relay connect vacuum pump work.
When the air pressure of the sealed gas chamber of vacuum force aid system and atmospheric difference of pressure during greater than 75KPaD; The voltage analog signal of vacuum pressure sensor is greater than 3.5V, and the digital signal that the A/D converter of vacuum servo system controller converts voltage analog signal to is greater than 179, and control chip is a low level to the drive level of transistor base; Transistor emitter and collecting electrode conducting channel are ended; Thereby the driving relay coil breaks off relay, and vacuum pump quits work.
The process that the modulus formula electric booster system of the utility model is controlled air pressure is divided into three kinds of states:
Initial start: this state is that electronlmobil does not start for a long time, and there is trickle gas leakage in sealed gas chamber, and sealed gas chamber air pressure and atmospheric gas pressure are approaching; Open key switch control power supply this moment; The output voltage of the signal output port of vacuum pressure sensor is 0.5V, and the vacuum servo system controller carries out being transferred to control chip after A/D transforms to this voltage analog signal handles the 8-4 pin of vacuum servo system controller and PF2 port output high level; Drive transistor base; Make the conducting of emitter and collector conducting channel, make the coil electricity of relay input circuit, the 19-3 pin of relay 19 and 19-5 pin are connected; This moment, the 8-3 pin of interface socket was communicated with vacuum pump work with the 8-1 pin.When the sealed gas chamber internal gas pressure reduces; The output voltage of vacuum pressure sensor 3 signal output ports raises; Pressure difference value raises and to be 75KPaD, and when the signal output port output voltage of vacuum pressure force gauge is a signal output port output voltage that 3.5V, pressure difference value are higher than 75KPaD and vacuum pressure sensor when being higher than 3.5V, the vacuum servo system controller transforms the back to voltage analog signal A/D and handles to control chip; The PF2 port output low level of control chip; Transistor emitter and collecting electrode conducting channel are closed, the relay coil dead electricity, and the 19-3 pin of relay 19 and 19-5 pin break off; This moment, the 8-3 pin and the 8-1 pin of interface socket broke off, and vacuum pump quits work.
Self-starting: when drag process or sealed gas chamber gas leakage, the sealed gas chamber internal pressure can raise, and difference of pressure reduces; When draught head is reduced to 50KPaD is that the signal output port output voltage of vacuum pressure sensor is when being lower than 2.5V; The vacuum servo system controller transforms the back to voltage analog signal A/D and handles to control chip, the PF2 port output high level of control chip, transistor emitter and the conducting of collecting electrode conducting channel; The relay coil energising; The 19-3 pin of relay 19 and 19-5 pin are connected, and this moment, the 8-3 pin and the 8-1 pin of interface socket were connected, and the vacuum pump self-starting is started working.
From stopping: the vacuum pump sealed gas chamber air pressure of bleeding reduces; Difference of pressure increases, and when draught head increases to more than the 75KPaD being the voltage of the signal output port output of vacuum pressure sensor when being higher than 3.5V, the vacuum servo system controller transforms the back to voltage signal A/D and gives control chip; The PF2 port output low level of control chip; Transistor emitter and collecting electrode conducting channel are closed, the relay coil dead electricity, and the 19-3 pin of relay 19 and 19-5 pin break off; This moment, the 8-3 pin and the 8-1 pin of interface socket broke off, and vacuum pump quits work.
Vacuum pump mode of operation cyclic process scheme drawing such as Fig. 5; The vacuum servo system is in logical 12V power supply a period of time; The vacuum pump periodical duty is closed key switch control power supply and is got into the initial start mode of operation, logical once more 12V power supply in self-starting, stop state certainly; Get into self-starting, stop certain mode of operation between the state certainly according to the different vacuum pumps of sealed gas chamber pressure, the vacuum pump periodical duty is in self-starting, stop state certainly afterwards.Realize that this logic control needs the control of vacuum servo system controller inner control chip program.
Fig. 6 is the diagram of circuit of vacuum servo system controller control vacuum pump work, and the air pressure of the sealed gas chamber of the vacuum servo system of the utility model and the scope of atmospheric difference of pressure are 50KPaD~75KPaD.For the air pressure of keeping vacuum servo system sealed gas chamber and atmospheric absolute value between 50KPaD ~ 75KPaD, realize control by vacuum servo system controller inner control chip.After the vacuum servo system controller powers on; Program entering initialization, the analog voltage signal that the pressure sensor signal output port is exported carry out the A/D conversion; And give variable P the conversion value assignment, variable P numerical value is compared; 3.5V the conversion value of voltage analog signal is 179, as p>179 the time, PF2 port output low level; 2.5V the conversion value of voltage analog signal is 128, when p 128 the time, PF2 port output high level, otherwise go to the A/D conversion program.
Certainly; The utility model also can have other various embodiments; Under the situation that does not deviate from the utility model spirit and essence thereof; Those of ordinary skill in the art work as can make various corresponding changes and distortion according to the utility model, but these corresponding changes and distortion all should belong to the protection domain of the appended claim of the utility model.