CN104554432A - Novel engineering machine steer-by-wire system - Google Patents

Novel engineering machine steer-by-wire system Download PDF

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Publication number
CN104554432A
CN104554432A CN201410230604.5A CN201410230604A CN104554432A CN 104554432 A CN104554432 A CN 104554432A CN 201410230604 A CN201410230604 A CN 201410230604A CN 104554432 A CN104554432 A CN 104554432A
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China
Prior art keywords
valve
steering
engineering machinery
oil
wire
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Granted
Application number
CN201410230604.5A
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Chinese (zh)
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CN104554432B (en
Inventor
韩嘉骅
蒲显坤
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Sichuan University
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Sichuan University
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Priority to CN201410230604.5A priority Critical patent/CN104554432B/en
Publication of CN104554432A publication Critical patent/CN104554432A/en
Application granted granted Critical
Publication of CN104554432B publication Critical patent/CN104554432B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D5/00Power-assisted or power-driven steering
    • B62D5/06Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/09Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by means for actuating valves
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D5/00Power-assisted or power-driven steering
    • B62D5/06Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle

Abstract

The invention provides a novel engineering machine steer-by-wire system and relates to a steering system which is applied to an engineering machine and can effectively save energy. The novel engineering machine steer-by-wire system mainly comprises a steering wheel, an angular displacement sensor, a force feedback motor, an ECU (Electric Control Unit), an energy accumulator, an electromagnetic on/off valve, a proportional three-way valve, a variable oil cylinder, a variable pump, an electromagnetic reversing valve, a check valve, a shuttle valve, a hydraulic control check valve, a steering oil cylinder, an overflowing valve, a displacement sensor L and a pressure sensor P. The invention designs the steer-by-wire system aiming at the disadvantages of an existing engineering machine constant displacement pump type steering system that the oil consumption is high; the working environment of a cab is bad; a driver easily feels tired, and the steering is not sensitive and the like; an oil supplying source adopts the variable pump and a manner of controlling the variable pump by the proportional three-way valve is adopted in a steering hydraulic system; the movement of a steering hydraulic cylinder is controlled by sufficiently utilizing the properties of variable displacement of the variable pump and the steering is realized; the system has better energy conservation property and controllability.

Description

A kind of New engineering machinery wire-controlled steering system
Technical field
The present invention relates to a kind of New engineering machinery wire-controlled steering system, be particularly a kind ofly applied in steering swivel system effectively energy-conservation in construction machinery and equipment.
Background technology
Along with the development of hydraulic pressure in engineering machinery field and Eltec, people to the riving condition of construction machinery and equipment and job requirement more and more higher, the product that significantly can reduce chaufeur labour intensity and reduce energy resource consumption is just more prone to win the market; Traditional construction machinery and equipment steering swivel system mainly adopts the interlock of hydraulic steering gear and flux amplification valve to realize turning to of construction machinery and equipment, this turning facilities machinery and hydraulic connecting complexity, troublesome poeration, therefore operate light, structure is simple, the construction machinery product that work efficiency is high become market in the urgent need to.
Chaufeur realizes turning to needing to realize following process at driving construction machinery and equipment: driver's operation wheel steering, deflector action control flux amplification valve break-make and direction, and fix-displacement pump exports fluid control steering cylinder and stretches.Because system adopts fix-displacement pump, system throttles and excess flow loss are very large.
The structure that what at present common on the market construction machinery and equipment steering swivel system adopted is as Fig. 1, its structure comprises 1-fix-displacement pump, 2-pressure-gradient control valve, 3-hydraulic steering gear, 4-steering cylinder, 5-flux amplification valve are formed.Bearing circle when not rotating, the port closing of deflector, guide's fluid flows back to fuel tank through deflector drain tap, and the spool of flux amplification valve is in meta under action of reset spring, and system does not turn to; When chaufeur steering wheel rotation, it is oil-filled to the two ends of flux amplification valve that bearing circle controls deflector, and now under the effect of guide oil liquid, Flow amplification valve core moves, and spool is opened, and fix-displacement pump and steering cylinder are connected, and system starts to turn to.When system stops turning to, the pilot pressure oil entering Flow amplification valve core one end then flows back to fuel tank by the restriction of flux amplification valve, the pressure at spool two ends, close to balance, is in meta at action of reset spring down-off amplifying valve spool, and system stops turning to.There is throttle loss and excess flow loss in many places in above steering procedure, such as: when system does not work, hydraulic oil directly flows back to fuel tank through by pass valve, has very large excess flow loss; When controlling to turn to, due to be control flux amplification valve the aperture size of restriction to control uninterrupted, throttle loss is larger; When turning to, chaufeur lacks the perception to road conditions.
Summary of the invention
In order to overcome the problem of above construction machinery and equipment steering swivel system in turning to, the invention is intended to design one effectively can reduce energy consumption, and make driver's operation simply light, system architecture is simple, and chaufeur has the steering swivel system of road feel.
Technical scheme provided by the present invention is: a kind of New engineering machinery wire-controlled steering system, and keystone configuration comprises: 1-controllable capacity pump bearing circle, 2-variable oil cylinder, 3-ratio triple valve, 4-electromagnetism on-off valve, 5-energy storage, 6-ECU (ECU (Electrical Control Unit)), 7-angular-motion transducer, 8-bearing circle, 9-force feedback motor, 10-steering cylinder, 11-hydraulic control one-way valve, 12-pressure sensor, 13-Fill valve, 14-shuttle valve, 15-hydraulic control one-way valve, 16-by pass valve, 17-solenoid directional control valve, 18-check valve, 19-by pass valve, 20-filter, 21-fuel tank.
Described New engineering machinery wire-controlled steering system, angular-motion transducer input end closure dish, mouth connects ECU, force feedback motor output end closure dish, input end connects ECU, and rotating of steering wheel, outputs to ECU by angular-motion transducer by turn sign; ECU is connected by the electric signal input end of mouth with ratio triple valve, sends actuating signal to ratio triple valve, ratio triple valve control variable oil cylinder, the change of the change control variable pump swashplate angle stretched along with piston rod; ECU is connected with two control ends of solenoid directional control valve by mouth, realizes by the control of ECU the commutation and the break-make that turn to oil circuit; Fill valve is connected on the loop between solenoid directional control valve and steering cylinder, and one end is connected to in-line, and the other end is connected to oil return line; Shuttle valve is connected on the loop between solenoid directional control valve and steering cylinder, and one end is connected to in-line, and the other end is connected to oil return line; By pass valve and pressure sensor is connected at the oil outlet of shuttle valve; Installation position displacement sensor on the piston rod of steering cylinder; Oil circuit between controllable capacity pump and solenoid directional control valve arranges check valve; Between check valve and solenoid directional control valve, arrange energy storage, install electromagnetism on-off valve and pressure sensor at input (going out) end of energy storage, the control end of electromagnetism on-off valve is connected to the delivery port of ECU.
Described New engineering machinery wire-controlled steering system, when construction machinery and equipment does not turn to and when bearing circle does not rotate, ECU does not receive the turn sign that bearing circle sends, now ratio triple valve is failure to actuate, and the right position control position of the rodless cavity direct passing ratio triple valve of variable oil cylinder is connected with fuel tank, and piston rod is in rightmost position, now, the swashplate angle of controllable capacity pump is minimum, that is controllable capacity pump oil outlet is closed, and system exports without hydraulic oil.
Described New engineering machinery wire-controlled steering system, when the firm quick steering of construction machinery and equipment, angular signal is passed to ECU by angular-motion transducer, signal is converted to tach signal by ECU, control signal is outputted to ratio triple valve by ECU, spool moves to right, and variable cylinder piston rod moves right, and promotes controllable capacity pump discharge capacity and increases; Turn sign is passed to solenoid directional control valve by ECU simultaneously, and electromagnetic switch valve events, to control position, by action while controllable capacity pump and solenoid directional control valve, realizes the quick steering of construction machinery and equipment.Bearing circle rotating speed is faster, and the displacement that the spool of ratio triple valve moves to right is larger, and piston rod moves to right larger, and controllable capacity pump discharge capacity is larger, turns to faster.While turning to, gather the stroke of hydraulic cylinder piston rod by displacement pickup, and the corner that itself and bearing circle export is compared determine whether that stopping turns to; The piston rod of variable oil cylinder is connected with the valve pocket of ratio triple valve, and when piston rod arrives certain position, ratio triple valve is closed and is in meta state, and now piston rod position is fixed, and controllable capacity pump is in quantitative fuel feeding.
Described New engineering machinery wire-controlled steering system, when the firm slow steeirng of construction machinery and equipment, angular signal is passed to ECU by angular-motion transducer, signal is converted to tach signal by ECU, control signal is outputted to ratio triple valve by ECU, and time at a slow speed, the electric signal that ECU issues ratio triple valve is less, now proportion electro-magnet is exerted oneself less, original spool force balance is broken, and moves to left, now under action of reset spring, variable cylinder piston rod is moved to the left, and promotes controllable capacity pump discharge capacity and reduces; Turn sign is passed to solenoid directional control valve by ECU, and electromagnetic switch valve events, to control position, by action while controllable capacity pump and solenoid directional control valve, realizes the slow steeirng of construction machinery and equipment.Bearing circle rotating speed is slower, and the displacement that the spool of ratio triple valve moves to left is larger, fewer by the fluid of variable oil cylinder, and controllable capacity pump discharge capacity is less, turns to slower.The piston rod of variable oil cylinder is connected with the valve pocket of ratio triple valve, and when piston rod arrives certain position, ratio triple valve is closed and is in meta state, and now piston rod position is fixed, and controllable capacity pump is in quantitative fuel feeding.While turning to, gather the stroke of hydraulic actuating cylinder by displacement pickup, and the corner that itself and bearing circle go out is compared determine whether that stopping turns to; The piston rod of variable oil cylinder is connected with the valve pocket of ratio triple valve, and when piston rod arrives certain position, ratio triple valve is closed and is in meta state, and now piston rod position is fixed, and controllable capacity pump is in quantitative fuel feeding.
Described New engineering machinery steering swivel system, in the process that construction machinery and equipment turns to, the data of the data gathered by hydraulic actuating cylinder displacement pickup and angular-motion transducer collection carry out real time contrast at ECU, whether corresponding with steering wheel angle to determine the steering angle of tire, if not corresponding, send instruction by ECU and correct.
Described New engineering machinery steering swivel system, when construction machinery and equipment turns to, during as occurred that steering power is not enough, send instruction by ECU to energy storage, electromagnetism on-off valve is opened, and energy storage is oil-filled to steering swivel system; When energy storage pressure is lower, ECU controls electromagnetism on-off valve, and system is oil-filled to energy storage.
Described New engineering machinery steering swivel system, in the process that construction machinery and equipment turns to, if when occurring that road surface is bad or turn to motionless, the pressure sensor detection pressure at shuttle valve place, if detection pressure is higher than the maximum delivery pressure of controllable capacity pump, now system can not turn to, and now ECU sends instruction to ratio triple valve, and the ratio triple valve of making is in rightmost position work, now controllable capacity pump claps hydraulic fluid port closedown, system unloaded, until system pressure recovers normal, then sends instruction by ECU and normally works.
Beneficial effect of the present invention is, Eltec and hydraulic technique is made full use of in construction machinery and equipment steering swivel system, Eltec is utilized to eliminate machinery more complicated in original steering swivel system and hydraulic connecting, steerman has good road feel, make full use of the change displacement control feature of controllable capacity pump, realize the ratio match of controllable capacity pump discharge capacity and rotating speed, the accuracy of steering angle is determined by the stroke comparing steering wheel angle and steering cylinder piston rod, make full use of the feature that controllable capacity pump volumetric void fraction efficiency of energy utilization is high, changing original throttling and overflow controls as volumetric void fraction, energy saving was improved more originally.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the present invention will be further described.
Fig. 1 is current construction machinery and equipment steering swivel system;
Fig. 2 is New engineering machinery wire-controlled steering system embodiment 1 constructional drawing;
Fig. 3 is New engineering machinery wire-controlled steering system embodiment 2 constructional drawing;
Fig. 4 is New engineering machinery wire-controlled steering system embodiment 3 constructional drawing;
Fig. 5 is New engineering machinery wire-controlled steering system embodiment 4 constructional drawing.
Detailed description of the invention
Embodiment one:
See Fig. 2, a kind of novel wire-controlled steering system, mainly comprises 1-controllable capacity pump bearing circle, 2-variable oil cylinder, 3-ratio triple valve, 4-electromagnetism on-off valve, 5-energy storage, 6-ECU (ECU (Electrical Control Unit)), 7-angular-motion transducer, 8-bearing circle, 9-force feedback motor, 10-steering cylinder, 11-hydraulic control one-way valve, 12-pressure sensor, 13-Fill valve, 14-shuttle valve, 15-hydraulic control one-way valve, 16-by pass valve, 17-solenoid directional control valve, 18-check valve, 19-by pass valve, 20-filter, 21-fuel tank.New engineering machinery wire-controlled steering system bearing circle connects ECU by angular-motion transducer; ECU is connected with bearing circle by force feedback motor; The electric signal input end of variable control valve is connected with the mouth of ECU, and the input end of ratio triple valve hydraulic oil is connected with external guide's oil circuit, and ratio triple valve hydraulic oil mouth is connected with variable oil cylinder; The swashplate angle control mechanism of controllable capacity pump is connected with variable cylinder piston rod, and controllable capacity pump oil outlet is connected with solenoid directional control valve; Solenoid directional control valve is connected with return opening with the oil-feed of steering cylinder; New engineering machinery wire-controlled steering system arranges two hydraulic control one-way valves, is connected on respectively on major loop; New engineering machinery wire-controlled steering system arranges shuttle valve and is connected on the major loop of New engineering machinery wire-controlled steering system, taps into oil circuit, and another side takes back oil circuit; Shuttle valve oil outlet connects by pass valve and pressure sensor.
Embodiment two:
See Fig. 3, be to have changed solenoid directional control valve into electro-hydraulic reversing valve with the difference of embodiment one, electro-hydraulic reversing valve is controlled by a solenoid directional control valve, and it controls oil sources is provided by external stable oil sources.
Embodiment three:
See Fig. 4, be the control fluid of ratio triple valve with the difference of embodiment one, provided by energy storage, the fluid that energy storage provides through reducing valve to ratio triple valve fuel feeding.
Embodiment four:
See Fig. 5, be with the difference of embodiment two and example three, energy storage provides to ratio triple valve and electro-hydraulic reversing valve simultaneously and controls oil, and the fluid flowed into from energy storage is through the sway of reducing valve control ratio direction valve spool; The fluid flowed into from energy storage to connect the oil inlet of solenoid directional control valve through reducing valve, solenoid directional control valve controls the sway of electro-hydraulic reversing valve spool.

Claims (9)

1. a novel wire-controlled steering system, mainly comprise bearing circle (8), angular-motion transducer (7), force feedback motor (9), ECU (ECU (Electrical Control Unit)) (6), energy storage (5), electromagnetism on-off valve (4), ratio triple valve (3), variable oil cylinder (2), controllable capacity pump (1), solenoid directional control valve (17), check valve (18), shuttle valve (14), hydraulic control one-way valve (12) (15), steering cylinder (10), by pass valve (16), by pass valve (19), displacement pickup L and pressure sensor P, it is characterized in that: described New engineering machinery wire-controlled steering system bearing circle connects ECU by angular-motion transducer, described New engineering machinery wire-controlled steering system ECU is connected with bearing circle by force feedback motor, the electric signal input end of ratio triple valve of described New engineering machinery wire-controlled steering system is connected with the electrical signal of ECU, and the input end of the hydraulic oil of ratio triple valve is connected with guide's oil circuit, and ratio triple valve hydraulic oil mouth is connected with variable oil cylinder, the swashplate angle control mechanism of described New engineering machinery wire-controlled steering system pump is connected with variable cylinder piston rod, pumps hydraulic fluid port and is connected with solenoid directional control valve, the described solenoid directional control valve of New engineering machinery wire-controlled steering system is connected with oil outlet with the oil inlet of steering cylinder, described New engineering machinery wire-controlled steering system arranges two hydraulic control one-way valves, is connected on respectively on major loop, described New engineering machinery wire-controlled steering system arranges shuttle valve and is connected on the major loop of New engineering machinery wire-controlled steering system, and tap into oil circuit, another side takes back oil circuit, described New engineering machinery wire-controlled steering system shuttle valve oil outlet connects by pass valve and pressure sensor.
2. New engineering machinery wire-controlled steering system according to claims 1, is characterized in that: described controllable capacity pump is vane type controllable capacity pump or plunger variable pump.
3. New engineering machinery wire-controlled steering system according to claims 1, is characterized in that: pump itself is accompanied with pressure compensation device.
4. New engineering machinery wire-controlled steering system according to claims 1, is characterized in that: shuttle valve oil outlet connects by pass valve and pressure sensor.
5. New engineering machinery wire-controlled steering system according to claims 1, is characterized in that: controllable capacity pump oil outlet connects solenoid directional control valve, and solenoid directional control valve oil outlet and oil inlet are connected oil inlet and the oil outlet of two steering cylinders respectively.
6. New engineering machinery wire-controlled steering system according to claims 1, is characterized in that: substitute solenoid directional control valve with electro-hydraulic reversing valve, and as the element controlling steering cylinder handling maneuver, its oil circuit control is by external stable Oil-source control.
7. New engineering machinery wire-controlled steering system according to claims 1 or 6, is characterized in that: between the oil outlet place check valve of solenoid directional control valve or electro-hydraulic reversing valve and pump, arrange energy storage, to steering swivel system repairing.
8. New engineering machinery wire-controlled steering system according to claims 7, is characterized in that: using energy storage directly as the pilot control that ratio triple valve is stable, energy storage by reducing valve to ratio triple valve fuel feeding.
9. New engineering machinery wire-controlled steering system according to claims 6, is characterized in that: described oil circuit control provides control oil sources by reducing valve to electro-hydraulic reversing valve by energy storage.
CN201410230604.5A 2014-05-29 2014-05-29 Engineering machine steer-by-wire system Expired - Fee Related CN104554432B (en)

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Application Number Priority Date Filing Date Title
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104925129A (en) * 2015-07-16 2015-09-23 潍柴动力股份有限公司 Hydraulic steering system
CN105539574A (en) * 2015-12-07 2016-05-04 中国北方车辆研究所 Automobile rear wheel steering electro-hydraulic system and control method thereof
CN106168238A (en) * 2015-05-19 2016-11-30 卡特彼勒公司 For estimating the system of pump delivery
CN106995005A (en) * 2017-05-02 2017-08-01 吉林大学 A kind of line traffic control hydraulic braking steering
CN107010106A (en) * 2017-04-19 2017-08-04 吉林大学 A kind of double steering power cylinder hydraulic pressure wire-controlled steering system simulated with road feel and method
EP3376055A4 (en) * 2015-11-13 2019-06-26 Shanghai Huace Navigation Technology Ltd. Hydraulic control valve assembly of automatic steering system for agricultural machinery
CN110431317A (en) * 2017-04-18 2019-11-08 川崎重工业株式会社 Oil hydraulic system
CN111086558A (en) * 2019-12-26 2020-05-01 北汽福田汽车股份有限公司 Hydraulic power-assisted steering system, control method and engineering vehicle

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CN1626392A (en) * 2003-12-10 2005-06-15 株式会社小松制作所 Vehicular steering control device
CN202429243U (en) * 2012-01-16 2012-09-12 中联重科股份有限公司 Servo steering controlling system and crane
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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106168238A (en) * 2015-05-19 2016-11-30 卡特彼勒公司 For estimating the system of pump delivery
CN106168238B (en) * 2015-05-19 2019-11-08 卡特彼勒公司 System for estimating the discharge capacity of pump
CN104925129A (en) * 2015-07-16 2015-09-23 潍柴动力股份有限公司 Hydraulic steering system
EP3376055A4 (en) * 2015-11-13 2019-06-26 Shanghai Huace Navigation Technology Ltd. Hydraulic control valve assembly of automatic steering system for agricultural machinery
CN105539574A (en) * 2015-12-07 2016-05-04 中国北方车辆研究所 Automobile rear wheel steering electro-hydraulic system and control method thereof
CN105539574B (en) * 2015-12-07 2017-09-26 中国北方车辆研究所 Automobile back wheel turns to electronically controlled hydraulic system and its control method
CN110431317A (en) * 2017-04-18 2019-11-08 川崎重工业株式会社 Oil hydraulic system
CN110431317B (en) * 2017-04-18 2020-08-11 川崎重工业株式会社 Oil pressure system
CN107010106B (en) * 2017-04-19 2018-08-28 吉林大学 A kind of double steering power cylinder hydraulic pressure wire-controlled steering system and method with road feel simulation
CN107010106A (en) * 2017-04-19 2017-08-04 吉林大学 A kind of double steering power cylinder hydraulic pressure wire-controlled steering system simulated with road feel and method
CN106995005A (en) * 2017-05-02 2017-08-01 吉林大学 A kind of line traffic control hydraulic braking steering
CN106995005B (en) * 2017-05-02 2018-02-13 吉林大学 A kind of line traffic control hydraulic braking steering
CN111086558A (en) * 2019-12-26 2020-05-01 北汽福田汽车股份有限公司 Hydraulic power-assisted steering system, control method and engineering vehicle

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