Summary of the invention
The present invention is the deficiency existing in above-mentioned prior art for avoiding, and a kind of electric controller of novel integrated electric electro-hydraulic proportional control system is provided, with reduce operator labor intensity, increase work efficiency and reliability.
The present invention be technical solution problem by the following technical solutions.
The electric controller of novel integrated electric electro-hydraulic proportional control system, its structural feature is to comprise control circuit and hydraulic system;
Described control circuit comprises intelligent controller U1 and motor-drive circuit; Described motor-drive circuit comprises the first motor-drive circuit and the second motor-drive circuit; Described the first motor-drive circuit comprises the first stepping motor control chip U2 and the first stepping motor drive ic U3; Described the second motor-drive circuit comprises the second stepping motor control chip U4 and the second stepping motor drive ic U5; Described Hall transducer is connected with described intelligent controller U1; Described the first stepping motor drive ic U3 is connected with described intelligent controller U1 by described the first stepping motor control chip U2, and described the second stepping motor drive ic U5 is connected with described intelligent controller U1 by the second stepping motor control chip U4;
Capacitor C 1, resistance R 1 and resistance R 2 are all connected with described the first stepping motor control chip U2, resistance R 3 is all connected with described the first stepping motor drive ic U3 with resistance R 4, and resistance R 3 is all connected with described the first stepping motor drive ic U2 again with resistance R 4 simultaneously; Capacitor C 2, resistance R 5 and resistance R 6 are all connected with described the first stepping motor control chip U4, resistance R 7 is all connected with described the first stepping motor drive ic U5 with resistance R 8, and resistance R 7 is all connected with described the first stepping motor drive ic U4 again with resistance R 8 simultaneously;
Described hydraulic system comprises oil pump, multiple directional control valve, inclination series flow control valve, lifting series flow control valve, steering system relief valve, power steering servo valve, hydraulic tilt cylinder, lifting hydraulic cylinder and power steering oil hydraulic cylinder; Described oil pump is connected with described multiple directional control valve, and described multiple directional control valve comprises four output ports: A1 port, A2 port, B2 port and PF port; Described multiple directional control valve is connected with described inclination series flow control valve by described A2 port, and described inclination series flow control valve is connected with the rod chamber of described hydraulic tilt cylinder; Described multiple directional control valve is connected with the rodless cavity of described hydraulic tilt cylinder by described B2 port; Described multiple directional control valve is connected with described lifting series flow control valve by described A1 port, and described lifting series flow control valve is connected with the rodless cavity of lifting hydraulic cylinder; Described steering system relief valve is all connected with the PF port of described multiple directional control valve with power steering servo valve, and described steering system relief valve is connected with power steering servo valve; Described power steering servo valve is connected with the rodless cavity of described power steering oil hydraulic cylinder;
The first stepping motor drive ic U3 is connected with the stepper motor of inclination series flow control valve, and the second stepping motor drive ic U5 is connected with the stepper motor of lifting series flow control valve.
The structural feature of the electric controller of novel integrated electric electro-hydraulic proportional control system of the present invention is also:
Described inclination series flow control valve and lifting series flow control valve are guide proportion and control series flow control valve, by stepper motor, are driven.
Described intelligent controller U1 is single-chip microcomputer STC12C5410AD.
Described multiple directional control valve adopts two-way self-closing electromagnetic iron and two coil configuration.
Compared with the prior art, beneficial effect of the present invention is embodied in:
The electric controller of novel integrated electric electro-hydraulic proportional control system of the present invention, when operator's mobile operating handle, Hall transducer detects the action of Joystick, operation signal is sent to intelligent controller U1, by intelligent controller U1, control signal is sent to two motor-drive circuits, by two motor-drive circuits, driven owing to controlling and the inclination series flow control valve of lifting and the stepper motor of lifting series flow control valve, thereby control the turnover oil mass of two series flow control valves, hydraulic tilt cylinder, lifting hydraulic cylinder are carried out to tilt operation and elevating control.Inclination series flow control valve, lifting series flow control valve are all connected with described intelligent controller U1, are detected the action of inclination series flow control valve, lifting series flow control valve by intelligent controller U1.Multiple directional control valve is connected with power steering servo valve with described steering system relief valve by described PF port, realize power-steering function, can meet to obtain under the different speed of a motor vehicle and different turn to requirement, make driver when automobile low speed driving, obtain larger power-assisted, improve travelling comfort and the Security of driving.
Inclination series flow control valve and lifting series flow control valve all adopt guide controlled proportional series flow control valve, and by step motor control, Novel electric electro-hydraulic proportional control system has been released a kind of system of valve characteristic formula of throttle valve of novel employing step motor control.Stepper valve has following features: the positional accuracy that has improved valve; In working procedure, when the electric current of supplying with to actuator is interrupted, can there is not because of the change of valve position quick variation in hydraulic coupling, and the out of order situation stability inferior of system is good.That Novel electric electro-hydraulic proportional control system has is simple in structure, stable performance, antijamming capability are strong, ambient temperature reaches 120 ℃, can meet engineering machinery, the job requirement of special-purpose vehicle (fork truck) fork truck, and can realize easily closed loop control.
The electric controller of novel integrated electric electro-hydraulic proportional control system of the present invention, have job requirement, the ambient temperature that can meet engineering machinery, special-purpose vehicle etc. reach 120 ℃, reduce operator labor intensity, increase work efficiency and reliability, make driver when automobile low speed driving, obtain the advantages such as larger power-assisted, the travelling comfort that improves driving and Security.
Embodiment
Referring to accompanying drawing 1~accompanying drawing 5, the electric controller of novel integrated electric electro-hydraulic proportional control system, comprises control circuit and hydraulic system;
Described control circuit comprises intelligent controller U1 and motor-drive circuit; Described motor-drive circuit comprises the first motor-drive circuit and the second motor-drive circuit; Described the first motor-drive circuit comprises the first stepping motor control chip U2 and the first stepping motor drive ic U3; Described the second motor-drive circuit comprises the second stepping motor control chip U4 and the second stepping motor drive ic U5; Described Hall transducer is connected with described intelligent controller U1; Described the first stepping motor drive ic U3 is connected with described intelligent controller U1 by described the first stepping motor control chip U2, and described the second stepping motor drive ic U5 is connected with described intelligent controller U1 by the second stepping motor control chip U4;
Capacitor C 1, resistance R 1 and resistance R 2 are all connected with described the first stepping motor control chip U2, resistance R 3 is all connected with described the first stepping motor drive ic U3 with resistance R 4, and resistance R 3 is all connected with described the first stepping motor drive ic U2 again with resistance R 4 simultaneously; Capacitor C 2, resistance R 5 and resistance R 6 are all connected with described the first stepping motor control chip U4, resistance R 7 is all connected with described the first stepping motor drive ic U5 with resistance R 8, and resistance R 7 is all connected with described the first stepping motor drive ic U4 again with resistance R 8 simultaneously;
Described hydraulic system comprises oil pump 6, multiple directional control valve 7, inclination series flow control valve 8, lifting series flow control valve 9, steering system relief valve 10, power steering servo valve 11, hydraulic tilt cylinder 12, lifting hydraulic cylinder 13 and power steering oil hydraulic cylinder 14; Described oil pump 6 is connected with described multiple directional control valve 7, and described multiple directional control valve 7 comprises four output ports: A1 port, A2 port, B2 port and PF port; Described multiple directional control valve 7 is connected with described inclination series flow control valve 8 by described A2 port, and described inclination series flow control valve 8 is connected with the rod chamber of described hydraulic tilt cylinder 12; Described multiple directional control valve 7 is connected with the rodless cavity of described hydraulic tilt cylinder 12 by described B2 port; Described multiple directional control valve 7 is connected with described lifting series flow control valve 9 by described A1 port, and described lifting series flow control valve 9 is connected with the rodless cavity of lifting hydraulic cylinder 13; Described steering system relief valve 10 is all connected with the PF port of described multiple directional control valve 7 with power steering servo valve 11, and described steering system relief valve 10 is connected with power steering servo valve 11; Described power steering servo valve 11 is connected with the rodless cavity of described power steering oil hydraulic cylinder 14;
The first stepping motor drive ic U3 is connected with the stepper motor of inclination series flow control valve 8, and the second stepping motor drive ic U5 is connected with the stepper motor of lifting series flow control valve 9.
Be illustrated in figure 1 the schematic diagram of hydraulic system.Piston is divided into rod chamber and rodless cavity by the cavity in oil hydraulic cylinder.Rod chamber refers to the cavity at the piston rod place of oil hydraulic cylinder, and described rodless cavity refers to the cavity of the interior side away from described piston rod of oil hydraulic cylinder.A1 port, A2 port, B2 port and PF port are the actuator port of multiple directional control valve, and P is filler opening, and O is return opening.P mouth is connected with oil pump, and O mouth is connected with oil-return groove.As Fig. 2 circuit diagram that is control circuit.
As Fig. 3~5, hand-operating device comprises Joystick 1 and base 2, within the lower end of described Joystick 1 is inserted in described base 2, the top of described base 2 is provided with handle pivoted housing 3, is provided with permanent magnetism bloom 4 and Hall transducer 5 within described handle pivoted housing 3; Described permanent magnetism bloom 4 is arranged on described handle pivoted housing 3, and described Hall transducer 5 is arranged on described Joystick 1.Hall transducer 5 is connected with described intelligent controller U1.The top of described Joystick 1 is provided with emergency stop button 15.
During specific works, when operator's mobile operating handle, Hall transducer detects the action of Joystick, operation signal is sent to intelligent controller U1, by intelligent controller U1, control signal is sent to two motor-drive circuits, by two motor-drive circuits, driven for controlling and the inclination series flow control valve of lifting and the stepper motor of lifting series flow control valve, thereby the turnover oil mass of two series flow control valves of control is carried out tilt operation and elevating control to hydraulic tilt cylinder, lifting hydraulic cylinder.Inclination series flow control valve, lifting series flow control valve are all connected with described intelligent controller U1, are detected the action of inclination series flow control valve, lifting series flow control valve by intelligent controller U1.Multiple directional control valve is connected with power steering servo valve with described steering system relief valve by described PF port, realize power-steering function, can meet to obtain under the different speed of a motor vehicle and different turn to requirement, make driver when automobile low speed driving, obtain larger power-assisted, improve travelling comfort and the Security of driving.Multiple directional control valve comprises inclined valve 71 and poppet valve 72.A2 port, B2 port are the output port of inclined valve 71, and A1 port is the output port of poppet valve 72.
Multiple directional control valve, is comprised of oil-feed valve block, Reversing valve plate and oil return valve block, for adapting to the requirement of different situations, can increase and decrease arbitrarily combination.Oil circuit adopts oil circuit in parallel.Valve block inside arranges one-way valve, for preventing that fluid from flowing backwards.Oil-feed valve block is with pilot operated compound relief valve, to control whole system pressure.The effect of diverter valve is that stable, constant fluid are offered to steering system diverter valve with a relief valve, and assurance steering system is normally worked.According to user's needs, Reversing valve plate can be equipped with overload valve to meet different actuator load needs.
Multiple directional control valve adopts two-way self-closing electromagnetic iron, adopts two coil configuration.Attract to be driven by pulse power supply with reset, there is the advantages such as power-saving, temperature rise is little, power is large.Electromagnet is connected with multiple directional control valve does heat insulation processing, controls electromagnet temperature and is no more than 80 ℃.Traditional electric-hydraulic proportion is controlled multi-way valve because ambient temperature can not be over 80 ℃, and fork truck hydraulic pressure axle temperature is often over 80 ℃, the fluid heat of controlling multi-way valve due to the electric-hydraulic proportion of integral type is conducted, electric-hydraulic proportion is controlled multi-way valve due to the restriction of electromagnetic property, the defects such as rate of fault is high, poor reliability that this has just caused in actual use.
The defect of using at present guide controlled proportional series flow control valve system to exist for hydraulic fork lift, electro-hydraulic proportional control system of the present invention has been released a kind of system of valve characteristic formula of throttle valve of novel employing step motor control.
Compare with traditional electrical magnet valve, stepper valve has following several feature.
1) improved the positional accuracy of valve; In working procedure, when the electric current of supplying with to actuator is interrupted, can there is not because of the change of valve position quick variation in hydraulic coupling, and the out of order situation stability inferior of system is good;
2) solenoid valve of traditional electronically controlled hydraulic system is due to the restriction of electromagnetic property, ambient temperature can not be over 80 ℃, and the ambient temperature of forklift engine chamber is through being everlasting between 80 ℃~100 ℃, this has just caused in actual use the defects such as rate of fault is high, poor reliability, and stepping throttle valve can normally be worked in the ambient temperature below 120 ℃, by stepper motor, rotated the position stopping, the on state of each valve port of definition stepper valve;
3) electro-hydraulic proportional control system of the present invention has that simple in structure, stable performance, antijamming capability are strong, ambient temperature reaches 120 ℃, can meet fork truck job requirement, and can realize easily closed loop control, replace electro-hydraulic servo control valve device poor reliability, high in cost of production defect.
Integrated manipulation is exactly with a Joystick, to complete all control actions of fork truck: the lean forward/hypsokinesis of forklift door frame rise/fall, fork of forklift truck.Can reduce operator's labor intensity, thereby raise labour efficiency.Also solved the difficult problem that forklift steering room space is arranged simultaneously.
The signal that Joystick position transducer sends changes with the variation of its actuated position, when handle is positioned at meta or antiposition operation, its output signal is between 0.6~2.8V, ECU controls the about 90mA of corresponding proportion valve electric current left and right, this Proportional valve is in closed condition, and corresponding pilot control oil pressure is zero (being failure to actuate); When operation, this handles position, its output signal is between 3.0~4.4V, with operation amplitude, increase, ECU controls corresponding proportion valve electric current and between 300~1000mA, changes in proportion thereupon, corresponding pilot control oil pressure changes between 0.5~2.9MPa, thereby controls corresponding action selector valve aperture.
For guaranteeing safety; at opening power and prestart; control gear ECU need confirm each actuated position to be positioned at meta, and (4 position sensor signal voltages all should be 2.5 ± 0.3V; otherwise with Joystick, at meta, the control ratio valve electric current of the lean forward/everythings such as hypsokinesis of forklift door frame rise/fall, fork of forklift truck is not entered to row lock protection, forbid its work.
Press emergency stop switch button, control gear ECU need confirm that each actuated position is positioned at meta, and control ratio valve electric current is entered to row lock protection, forbids its work.
Described inclination series flow control valve 8 and lifting series flow control valve 9 are guide proportion and control series flow control valve, by stepper motor, are driven.
Described intelligent controller U1 is single-chip microcomputer STC12C5410AD.
Described multiple directional control valve 7 adopts two-way self-closing electromagnetic iron and two coil configuration.
The preferred STC12C5410AD of intelligent controller U1.STC12C5410 series monolithic is the compatibility 8051 kernel single-chip microcomputers by the single clock/machine cycle (1T) of macrocrystalline science and technology production, a new generation's 8051 single-chip microcomputers of high speed/low power consumption, brand-new production line/Reduced Instruction Set Computer Architecture, inner integrated MAX810 Special reset circuit.
Two motor-drive circuits are all by the multifunctional circuit that drives control logic chip L297 and chip L298N to form.The I/O mouth output control pulse of single-chip microcomputer, processes through L297, L298N drive circuit paired pulses, the driving signal of output energy direct controlling and driving motor or stepper motor.
The first stepping motor control chip U2 and the second stepping motor control chip U4 are L297.L297 is the stepper motor nonshared control unit that Italian SGS semiconductor company produces, it can produce 4 phase control signals, can be used for the bipolar and four phase single-phase stepper motors of computer-controlled two-phase, can enough lists four clap, two four clap, four phase eight beat mode control step motor.PWM chopper circuit in chip can regulate the electric current in the motor winding in stepper motor winding under switching mode.This intergrated circuit adopts the I2L technology of the analog/digital compatibility of LiaoSGS company, uses the supply voltage of 5V, and all the connection of signal is all compatible with TFL/CMOS or open-collector transistor.L297 chip is the Step-motor Control device with the dual inline type plastic-packaged of 20 pins.It can produce four and drive mutually signal, can drive the bipolar or four phase unipolar stepper motors of Single-chip Controlling two-phase by modes such as half step (eight clap) and full steps (four bats).The PWM chopper of this chip internal allows control step motor winding current under the pattern of pass, because phase sequential signal is also produced by inside, therefore it only needs clock, direction and the mode input signal just can control step motor, can alleviate the burden of microprocessor and programming.
The first stepping motor drive ic U3 and the second stepping motor drive ic U5 are L298N.A kind of high voltage that L298N ShiST company produces, large-current electric machine drive chip.This chip adopts 15 pin encapsulation.Main feature is: operating voltage is high, and maximum operating voltage can reach 46V; Output current is large, and instantaneous peak current can reach 3A, and continuous firing electric current is 2A; The high-voltage large current full-bridge type driver that includes two H bridges, can be used for driving the inductive loads such as direct current motor and stepping motor, relay coil; Adopt standard logic level signal to control; There are two and enable control end, in the situation that not affected by input signal, allow or forbid that device work has a logic power input end, internal logic circuit part is worked under low voltage; Can external detection resistance, variable quantity is fed back to control circuit.Use L298N chip drives motor, this chip can drive two two-phase electric machines, also can drive four phase motors, can directly by power supply, carry out regulation output voltage; And can directly with the I/O mouth of single-chip microcomputer, provide signal, circuit is simple, uses more convenient.
As shown in Figure 1, the hydraulic system of the electric controller of engineering machinery, the novel integrated electric electro-hydraulic proportional control system of special-purpose vehicle (fork truck) forms the composition such as the unit that mainly contains gear pump, multiple directional control valve, guide controlled proportional series flow control valve, hydraulic tilt cylinder, lifting hydraulic cylinder, power-assisted steering, pressure security protection.
Multiple directional control valve adopts two-way Self-retaining electromagnet to adopt two coil configuration, after coil electricity, and the position (self-locking) of energy retainer shaft core after energising displacement, and no longer need the input of electric power to maintain.Attract to be driven by pulse power supply with reset.There is the advantages such as power-saving, temperature rise is little, power is large.
Guide controlled proportional series flow control valve adopts step motor control, Novel electric electro-hydraulic proportional control system to release a kind of system of valve characteristic formula of throttle valve of novel employing step motor control.Compare with solenoid valve, stepper valve has following features: the positional accuracy that has improved valve; In working procedure, when the electric current of supplying with to actuator is interrupted, can there is not because of the change of valve position quick variation in hydraulic coupling, and the out of order situation stability inferior of system is good.That Novel electric electro-hydraulic proportional control system has is simple in structure, stable performance, antijamming capability are strong, ambient temperature reaches 120 ℃, can meet engineering machinery, the job requirement of special-purpose vehicle (fork truck) fork truck, and can realize easily closed loop control.
As Fig. 2, front while pushing away Joystick, tilt operation signal is exported at 0.6~2.2V; During post-tensioning Joystick, tilt operation signal is exported at 2.8~4.4V.When a left side pushes away Joystick, descending operation signal is exported at 0.6~2.2V; When the right side pushes away Joystick, descending operation signal is exported at 2.8~4.4V.
The signal that Joystick sends changes with the variation of its actuated position, and when handle is positioned at meta or antiposition operation, its output signal is between 0.6~2.8V; When handle is positioned at forward (front push away or the right side pushes away) operation, its output signal is between 2.8~4.4V, integrated hydraulic is handled the integrated hydraulic operation electric controller output of electric controller output step motor control logic step motor control logic, drive No. two stepper motors, by guide controlled proportional series flow control valve, control respectively and lifting, while output control logic, in controlling inclined valve and poppet valve.
Above control procedure realizes by the schematic circuit shown in Fig. 2.The hall element output signal of Joystick is given computer STC12C5410AD, the control signal of computer unit output by the logic drive circuit control step motor and inclined valve, lift valve that are comprised of chip L297 and L298 and transistor, operates control thereby realize respectively; When handle is positioned at meta, computer unit output stop control signal, stops and resetting system is handled.
For guaranteeing safety; at opening power and prestart; first control gear confirms that each actuated position is positioned at meta; be that handle output signal voltage all should be 2.5 ± 0.3V; otherwise with Joystick, at meta, the control signal of the lean forward/everythings such as hypsokinesis of forklift door frame rise/fall, fork of forklift truck is not entered to row lock protection, forbid its work.Press emergency stop switch button 15, control gear confirms that each actuated position is positioned at meta, and control ratio valve electric current is entered to row lock protection, forbids its work.
As shown in Fig. 3~5, hand-operating device includes Joystick and handle pivoted housing, and a pair of Hall element (being Hall transducer) and permanent magnetism bloom (being magnet steel) are installed respectively in the two corresponding position.When handle pivoted housing rotates, the relative position of Hall element and magnet steel changes, and the signal that sensor sends changes with its change of distance, when handle is positioned at meta, its output signal is between 2.5 ± 0.3V, when when operation, this handles position, handle pivoted housing rotates, and its output signal is between 2.8~4.4V or 0.6~2.2V, output signal increases with operation amplitude and away from 2.5V, handle top button is pressed and is, is meta shut-down operation, and now output signal is 2.5V.
Joystick position transducer, being the signal that sends of Hall transducer changes with the variation of its actuated position, when handle is positioned at meta or antiposition operation, its output signal is between 0.6~2.8V, ECU controls the about 90mA of corresponding proportion valve electric current left and right, this Proportional valve is in closed condition, and corresponding pilot control oil pressure is zero (being failure to actuate); When operation, this handles position, its output signal is between 3.0~4.4V, with operation amplitude, increase, ECU controls corresponding proportion valve electric current and between 300~1000mA, changes in proportion thereupon, corresponding pilot control oil pressure changes between 0.5~2.9MPa, thereby controls corresponding action selector valve aperture.
For guaranteeing safety; at opening power and prestart; control gear ECU need confirm each actuated position to be positioned at meta, and (4 position sensor signal voltages all should be 2.5 ± 0.3V; otherwise with Joystick, at meta, the control ratio valve electric current of the lean forward/everythings such as hypsokinesis of forklift door frame rise/fall, fork of forklift truck is not entered to row lock protection, forbid its work.
Press emergency stop switch button 15, control gear ECU need confirm that each actuated position is positioned at meta, and control ratio valve electric current is entered to row lock protection, forbids its work.
The electric controller circuit theory diagrams of novel integrated electric electro-hydraulic proportional control system as shown in Figure 2.
Before while pushing away Joystick, tilt operation signal is exported at 0.6~2.2V; During post-tensioning Joystick, tilt operation signal is exported at 2.8~4.4V.
When a left side pushes away Joystick, descending operation signal is exported at 0.6~2.2V; When the right side pushes away Joystick, descending operation signal is exported at 2.8~4.4V.
The signal that Joystick sends changes with the variation of its actuated position, and when handle is positioned at meta or antiposition operation, its output signal is between 0.6~2.8V; When handle is positioned at forward (front push away or the right side pushes away) operation, its output signal is between 2.8~4.4V, integrated hydraulic is handled the integrated hydraulic operation electric controller output of electric controller output step motor control logic step motor control logic, drive No. two stepper motors, by guide controlled proportional series flow control valve, control respectively and lifting, while output control logic, in controlling inclined valve and poppet valve.
Above control procedure realizes by the schematic circuit shown in Fig. 2.The hall element output signal of Joystick is given computer STC12C5410AD, the control signal of computer unit output by the logic drive circuit control step motor and inclined valve, lift valve that are comprised of chip L297 and L298 and transistor, operates control thereby realize respectively; When handle is positioned at meta, computer unit output stop control signal, stops and resetting system is handled.
For guaranteeing safety; at opening power and prestart; first control gear confirms that each actuated position is positioned at meta; be that handle output signal voltage all should be 2.5 ± 0.3V; otherwise with Joystick, at meta, the control signal of the lean forward/everythings such as hypsokinesis of forklift door frame rise/fall, fork of forklift truck is not entered to row lock protection, forbid its work.Press emergency stop switch button, control gear confirms that each actuated position is positioned at meta, and control ratio valve electric current is entered to row lock protection, forbids its work.
The electric controller of novel integrated electric electro-hydraulic proportional control system of the present invention, simple in structure, to handle reliably, device manipulation space is arranged easily; Operating grip adopts Hall element, simple in structure, and precisely, reliably, process control is stable for action control, and rapidly, accurately, antijamming capability is strong in multiple logic control enforcement; Pressure output control is stable.