A kind of level comparison module for the electric-controlled hydraulic steering hardware
Technical field
The utility model relates to the automobile electrical control hydraulic steering system field, is specifically related to a kind ofly can change by-pass collar and the control setup thereof that enters flow stream pressure and flow in the power steering rotary valve, is applicable to the commercial vehicle/comm..vehicles such as motor omnibus, goods carrying vehicle.
Background technology
At present, widespread use is hydraulic power-assist steering system in the commercial vehicle/comm..vehicle field, only has fixing hand force property, when the automobile low speed driving, steering wheel operating has preferably portability, when the speed of a motor vehicle faster the time, the power steerig pump rotating speed also rises, cause the flow of hydraulic oil to increase, produce larger power-assisted, so that rotating of steering wheel is too light, easily lose road feel, produce the problem of automobile " unstable ", reduced the safety performance that commercial vehicle/comm..vehicle is run at high speed, also be unfavorable for the requirement of vehicle energy saving.Because the conventional hydraulic servo steering system can't effectively solve the contradiction that turns to " gently " and " spirit ", and the problem that mutually restricts of steering effort and road feel, so people propose Electro-Hydraulic Power Steering System and control the flow that enters convertible valve, to obtain good power-assisted feel.This system can be divided into three kinds of major control modes such as electromagnetic valve flow control formula, stepping motor drive control valve flow control formula, motor direct-drive oil pump flow control formula according to the volume control device difference at present.
In existing scheme, adopt stepping motor to regulate the restriction size of bypass disc in the china national practical new-type patent 200320118460.1, enter into the hydraulic fluid flow rate of steering control valve with control.The problem of forfeiture road feel when this improvement project can solve to a certain extent automobile high-speed and turns to, but this form structure is complicated, and cost is higher, and is wayward; Adopted electromagnetic proportional valve to regulate the restriction size of bypass disc in the china national practical new-type patent 200820227155.9, thereby the flow of control hydraulic oil, but this scheme is higher to the accuracy requirement of electromagnetic proportional valve itself, also comparatively harsh to the requirement of controller, and needle-valve often bears in actual use incessantly high pressure and unsettled phenomenon occurs opening; Adopt DC machine directly to drive oil pump in the china national practical new-type patent 200720034596.2, big or small indirectly control Hydraulic Pump flow and pressure by control power line voltage and electric current, this structure has increased motor and other bindiny mechanisms on the basis of original power steering, structure is more complicated, and also is difficult point to the control of DC machine.
Above-mentioned these scheme ubiquities are wayward, and cost of product is higher, and the deficiencies such as complex structure are difficult to obtain the good power-assisted feel of chaufeur needs.The deficiencies in the prior art are existing a kind ofly to be kept on original hydraulic power-assist steering system basis, is setting up a cover multifunctional electromagnetic valves unit as bleed off circuit in order to overcome, can realize that by accurate control the bypass oil mass is multistage adjustable, the Electro-Hydraulic Power Steering System that assist characteristic is better.
The utility model content
The level comparison module that the utility model relates to is for the electric-controlled hydraulic steering hardware, control setup can carry out complete closure to electromagnetic valve according to sensor signal, single unlatching, full open is the combination control of totally four kinds of array modes, the utility model in use, when chaufeur just starts automobile, need relatively large power steering, this moment, electromagnetic valve assembled unit two closed electromagnetic valves did not play bypass action, increase along with the speed of a motor vehicle, controller as required, open the less electromagnetic valve of one of them latus rectum, in the time of the automobile high speed, open the larger electromagnetic valve of latus rectum, by the time at a high speed the time, with whole valve opens, reduce the hydraulic fluid flow rate that enters in the steering control valve with this, thereby increase steering effort, to avoid losing road feel, improve the safety performance of whole steering swivel system, in addition, for the operating mode that promptly turns to greatly at a high speed, control setup can be made the instruction of contract fully to two electromagnetic valves in conjunction with the deflection angle speed sensor signal, thereby effectively solves the light safety problem that turns under this kind dangerous working condition.
Vehicle speed signal from the gauge panel taking-up, it is the square-wave signal that frequency changes with the speed of a motor vehicle, frequency is directly proportional with the speed of a motor vehicle substantially, need nurse one's health vehicle speed signal and to make it become desirable square wave, via frequently-press conversion chip 21 to change level signal with frequency change into, LM331 powers through power module, and peripheral as long as just can reach the purpose of voltage to frequency conversion with a small amount of resistance and electric capacity, level comparison module 22 is by 3 comparators 19 and four resistance R
1, R
2, R
3, R
4Form, four resistance play the dividing potential drop effect, 3 kinds of different reference voltages are provided for comparator 19, are respectively V
0, V
1, V
2And V
0<V
1<V
2
As LM331 output voltage V<V
0The time, I
2I
1I
0=000
*
Work as V
0<V<V
1The time, I
2I
1I
0=001;
Work as V
1<V<V
2The time, I
2I
1I
0=011;
Work as V〉V
2The time, I
2I
1I
0=111;
* 0 presentation logic low level, 1 presentation logic high level.
The high-low level signal of level comparison module 22 output is input to logical operation module 23, and logical operation module 23 is by two phase inverters, two and door and one or form Y
0, Y
1It is the high-low level signal of logical operation module output.
Work as I
2I
1I
0=000
*The time, Y
1Y
0=00;
Work as I
2I
1I
0=001 o'clock, Y
1Y
0=01;
Work as I
2I
1I
0=011 o'clock, Y
1Y
0=10;
Work as I
2I
1I
0=111 o'clock, Y
1Y
0=11;
Y
0, Y
1Control respectively the T of solenoid valve driving module 24
1, T
2, T
1, T
2Be the N-channel MOS pipe, therefore the advantage such as it has, and input resistance is high, noise is little, stability low in energy consumption, warm is good is widely used in the power level amplifying circuit.T in the solenoid valve driving module 24
1, T
2Play the electronics on-off action, when the grid input high level, power tube is opened, and has electric current to flow through in the driving circuit, and electromagnetic valve is opened; When the grid input low level, power tube is closed, and electromagnetic valve restPoses.R
5, R
7Dropping resistor satisfying the requirement of electric current in the circuit, and R
5, R
7Be adjustable resistance, can be adjusted accordingly according to the electromagnetic valve of different latus rectums R
6, R
8Be feedback resistance, in order to detect the electric current in the driving circuit, do overcurrent protection, D
1, D
2Be the flywheel diode of two electromagnetic valves, provide current by pass when giving closed electromagnetic valve, be unlikely to make the high electrical breakdown metal-oxide-semiconductor of electromagnetic valve coil generation, also improved speed of response simultaneously.
The 25th, power module mainly is that the voltage transition of storage battery 24V is each chip and the required voltage of circuit.
The 26th, the line under-voltage protection module guaranteeing the reliability service of electromagnetic valve, is crossed when low when the under-voltage protection module detects the power supply power supply, and under-voltage protection module output low level is turn-offed the power tube that drives electromagnetic valve, and provided failure alarm signal.
The 27th, overcurrent protection module, when certain reason (such as the electromagnetic valve coil short circuit) causes the electric current of driving circuit excessive, overcurrent protection module output low level, the equal output low level of the AND2 in the module 23 and AND3, thereby the T in the module 24
1, T
2Close, electromagnetic valve is also closed.
After the utility model adopts said structure, electromagnetic valve has been realized the control function of four kinds of array modes in the assembled unit according to control signal, the required steering effort that applies of chaufeur is controlled in the suitable scope, also solved for the light safety problem that turns under the urgent large steering situation of high speed, and realize the output complete characteristic curve, as shown in Figure 5.The utility model circuit is simple, and the life-span is permanent, easily realizes accurately control, has solved the problem of " unstable ", has improved safety and the road-holding property of running car.
Description of drawings
Fig. 1 is the controller diagram of circuit of electric-controlled hydraulic steering hardware;
Fig. 2 is the inner function module structured flowchart that comprises the electric-controlled hydraulic steering hardware of level comparison module
Among the figure: 19, comparator; 20, Digital Logic gate circuit; 21, frequently-the pressure conversion chip; 22, level comparison module; 23, logical operation module; 24, solenoid valve driving module; 25, power module; 26, line under-voltage protection module; 27, overcurrent protection module.
The specific embodiment
Below in conjunction with accompanying drawing the utility model is described in further detail.
In the utility model, control setup can carry out complete closure to electromagnetic valve according to sensor signal, single unlatching, full open is the combination control of totally four kinds of array modes, the utility model in use, when chaufeur just starts automobile, need relatively large power steering, this moment, electromagnetic valve assembled unit two closed electromagnetic valves did not play bypass action, increase along with the speed of a motor vehicle, controller is opened the less electromagnetic valve of one of them latus rectum, in the time of the automobile high speed as required, open the larger electromagnetic valve of latus rectum, by the time at a high speed the time, with whole valve opens, reduce the hydraulic fluid flow rate that enters in the steering control valve with this, thereby increase steering effort, to avoid losing road feel, improve the safety performance of whole steering swivel system, in addition, for the operating mode that promptly turns to greatly at a high speed, control setup can be made the instruction of contract fully to two electromagnetic valves in conjunction with the deflection angle speed sensor signal, thereby effectively solves the light safety problem that turns under this kind dangerous working condition, specifically is described further in conjunction with Fig. 1:
Vehicle speed signal from the gauge panel taking-up, it is the square-wave signal that frequency changes with the speed of a motor vehicle, frequency is directly proportional with the speed of a motor vehicle substantially, need nurse one's health vehicle speed signal and to make it become desirable square wave, via frequently-press conversion chip 21 to change level signal with frequency change into, LM331 powers through power module, and peripheral as long as just can reach the purpose of voltage to frequency conversion with a small amount of resistance and electric capacity, level comparison module 22 is by 3 comparators 19 and four resistance R
1, R
2, R
3, R
4Form, four resistance play the dividing potential drop effect, 3 kinds of different reference voltages are provided for comparator 19, are respectively V
0, V
1, V
2And V
0<V
1<V
2
As LM331 output voltage V<V
0The time, I
2I
1I
0=000
*
Work as V
0<V<V
1The time, I
2I
1I
0=001;
Work as V
1<V<V
2The time, I
2I
1I
0=011;
Work as V〉V
2The time, I
2I
1I
0=111;
* 0 presentation logic low level, 1 presentation logic high level.
The high-low level signal of level comparison module 22 output is input to logical operation module 23, and logical operation module 23 is by two phase inverters, two and door and one or form Y
0, Y
1It is the high-low level signal of logical operation module output.
Work as I
2I
1I
0=000
*The time, Y
1Y
0=00;
Work as I
2I
1I
0=001 o'clock, Y
1Y
0=01;
Work as I
2I
1I
0=011 o'clock, Y
1Y
0=10;
Work as I
2I
1I
0=111 o'clock, Y
1Y
0=11;
Y
0, Y
1Control respectively the T of solenoid valve driving module 24
1, T
2, T
1, T
2Be the N-channel MOS pipe, therefore the advantage such as it has, and input resistance is high, noise is little, stability low in energy consumption, warm is good is widely used in the power level amplifying circuit.T in the solenoid valve driving module 24
1, T
2Play the electronics on-off action, when the grid input high level, power tube is opened, and has electric current to flow through in the driving circuit, and electromagnetic valve is opened; When the grid input low level, power tube is closed, and electromagnetic valve restPoses.R
5, R
7Dropping resistor satisfying the requirement of electric current in the circuit, and R
5, R
7Be adjustable resistance, can be adjusted accordingly according to the electromagnetic valve of different latus rectums R
6, R
8Be feedback resistance, in order to detect the electric current in the driving circuit, do overcurrent protection, D
1, D
2Be the flywheel diode of two electromagnetic valves, provide current by pass when giving closed electromagnetic valve, be unlikely to make the high electrical breakdown metal-oxide-semiconductor of electromagnetic valve coil generation, also improved speed of response simultaneously.
The 25th, power module mainly is that the voltage transition of storage battery 24V is each chip and the required voltage of circuit.
The 26th, the line under-voltage protection module guaranteeing the reliability service of electromagnetic valve, is crossed when low when the under-voltage protection module detects the power supply power supply, and under-voltage protection module output low level is turn-offed the power tube that drives electromagnetic valve, and provided failure alarm signal.
The 27th, overcurrent protection module, when certain reason (such as the electromagnetic valve coil short circuit) causes the electric current of driving circuit excessive, overcurrent protection module output low level, the equal output low level of the AND2 in the module 23 and AND3, thereby the T in the module 24
1, T
2Close, electromagnetic valve is also closed.
After the utility model adopts said structure, electromagnetic valve has been realized the control function of four kinds of array modes in the assembled unit according to control signal, the required steering effort that applies of chaufeur is controlled in the suitable scope, also solved for the light safety problem that turns under the urgent large steering situation of high speed, and realized the output complete characteristic curve.The utility model circuit is simple, and the life-span is permanent, easily realizes accurately control, has solved the problem of " unstable ", has improved safety and the road-holding property of running car.