CN101936018A - Electro-hydraulic proportion control system of loader - Google Patents
Electro-hydraulic proportion control system of loader Download PDFInfo
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- CN101936018A CN101936018A CN 201010241656 CN201010241656A CN101936018A CN 101936018 A CN101936018 A CN 101936018A CN 201010241656 CN201010241656 CN 201010241656 CN 201010241656 A CN201010241656 A CN 201010241656A CN 101936018 A CN101936018 A CN 101936018A
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Abstract
The invention discloses an electro-hydraulic proportion control system of a loader, and belongs to the electro-hydraulic proportion control system which is used in engineering machinery. An oil outlet of an oil pump of a double oil pump of the control system is connected with an input port of a pilot control valve bank through a safety valve, wherein an operating handle, a movable arm positioning sensor and a leveling sensor are connected with an input end of a computer control module; an output end of the computer control module is connected with a control end of the pilot control valve bank; the output end of the pilot control valve bank is connected with the input end of a D32 multi-path valve; another oil pump of the double oil pump is connected with the input end of the D32 multi-way valve; the output end of the D32 multi-way valve is connected with a bucket oil cylinder and a movable arm oil cylinder; the D32 multi-way valve is connected with an oil tank through a radiator; and an oil suction end of the double oil pump is connected with the oil tank through a filter. The system has the advantages of reducing the labor intensity of a driver, improving the operating efficiency, completely monitoring and coordinating the state of the entire machine and improving the labor efficiency, along with small operating force and high system reliability.
Description
Technical field
The present invention relates to the electro-hydraulic proportional control system of a kind of use in engineering machinery, particularly a kind of loader electro-hydraulic proportional control system.
Background technology
The equipment of loader is to utilize HYDRAULIC CONTROL SYSTEM swing arm and bucket cylinder to finish operations such as spading, loading.The control system that the control spading loads action is the key technology that influences the complete machine performance.
At present, domestic loader operation joystick adopts manually direct manipulation and hydraulic pilot to handle the commutation of main reversing valve spool, can not return meta automatically after its steering force is big, lever operated, shortcoming such as reversing impact is big, control function singleness, operator's fatiguability, moulding are not attractive in appearance.
Summary of the invention
The objective of the invention is to provide a kind of: the loader electro-hydraulic proportional control system, the operating physical force that solves the existing operating system of loader is big, commutating speed is uncontrollable, impact is big, the problem of function singleness.
The object of the present invention is achieved like this: this control system comprises double-united oil pump, safety valve, the pilot-actuated valve group, operating grip, controller, the swing arm alignment sensor, the sensor of flating pass struggles against, the D32 banked direction control valves, bucket cylinder, boom cylinder, scraper bowl operating grip and swing arm operating grip, the oil-out of an oil pump of double-united oil pump is connected with pilot-actuated valve group input port by safety valve, operating grip, the swing arm position is decided sensor and is connected with the input of computer control module with the bucket sensor of flating pass, and the output of computer control module is connected with the control end of pilot-actuated valve group; The output of pilot-actuated valve group is connected with the input of D32 banked direction control valves, another oil pump of double-united oil pump is connected with the input of D32 banked direction control valves, the output of D32 banked direction control valves is connected with boom cylinder with bucket cylinder, the D32 banked direction control valves is connected with fuel tank by radiator, and the oil absorbing end of double-united oil pump is by the strainer connected tank.
Described controller is a computer control module.
Control method is: 1, offer the different control signal of computer control module by the different position of operating grip; 2, computer control module is amplified the corresponding proportion electro-magnet of rear drive with different control signals; 3, electro-hydraulic proportional reducing valve output control corresponding pressure oil, simultaneous computer control module are according to the switch of different operating handle signal controlling solenoid operated directional valve, thus the flow direction of the pilot pressure oil of control reducing valve output; 4, moving of the corresponding spool of pilot pressure oil control D32 banked direction control valves, the flow direction of control working connection pressure oil, and then the control of realization equipment; 5, the swing arm alignment sensor is used to set the position of moved arm lifting, and constantly detects the swing arm location transmission and give controller, is convenient to real-time monitoring, realizes the swing arm automatic positioning function; 6, scraper bowl is set level and is automatically replied the spading state when sensor is used for entering the spading position after scraper bowl unloads; 7, thick/smart mode-conversion switch is in when disconnecting, and is quick mode; When closed is the accurate operation pattern, and this moment, the output pwm signal dutycycle was less, and controlled pressure is less, and promptly control ratio reducing valve output pressure is less, and the major loop flow diminishes accordingly.
Beneficial effect, owing to adopted such scheme, the electric control operation handle is carried the instruction control signal to controller, variation along with handle position, export the corresponding signal of telecommunication, signal is amplified and drive corresponding proportion electro-magnet by controller, thus control electro-hydraulic proportional reducing valve output control corresponding pressure oil, the displacement of control main reversing valve spool.The while controller is according to the switch of different handle signal controlling solenoid operated directional valves, thus the direction of displacement of control spool, the flow direction of control working connection pressure oil, and then the control of realization equipment.The swing arm alignment sensor is used to set the position of moved arm lifting, and constantly detects the swing arm location transmission and give controller, is convenient to real-time monitoring, realizes the swing arm automatic positioning function; Scraper bowl is set level and is automatically replied the spading state when sensor is used for entering the spading position after scraper bowl unloads.
Solved that the existing Operational System Control power of loader is big, commutating speed is uncontrollable, impact is big, the problem of function singleness, has reached purpose of the present invention.
Advantage:
1, adopted electric control handle, operating physical force is little, has reduced driver's labour intensity;
2, can control commutating period, reduce commutating period, improve system reliability;
3, can set the swing arm working region arbitrarily, and realize setting level automatically of scraper bowl, the operation that realizes semi-automation improves operating efficiency;
4, controller adopts computer control module control, can monitor the duty of working device of loader easily, can carry out communication with main control module easily to the state of being monitored, and the state of complete machine is carried out comprehensive monitoring and coordination;
5, joystick reaches the signal of telecommunication guide proportion reducing valve that is installed on the loader frame, just will be installed in noise, heat and the active force that the manual pilot proportional reducing valve of driver's cabin inside produced originally and move to the driver's cabin outside, driver's cabin can better seal simultaneously, helps the driver's cabin noise reduction.
6, computer control module has realized the electric-hydraulic proportion control to working device of loader, has improved the control performance of loader, has alleviated operator's labour intensity, has improved efficiency.
Description of drawings
Fig. 1 is the schematic diagram of loader electro-hydraulic proportional control system.
Fig. 2 is the operating grip structural representation.
Fig. 3 is swing arm, scraper bowl hydraulic cylinder control flow chart.
Fig. 4 is the basic comprising figure of electro-hydraulic proportional control system.
Among the figure, 1, double-united oil pump; 2, safety valve; 3, pilot-actuated valve group; 4, operating grip; 5, controller; 6, swing arm alignment sensor; 7, the bucket sensor of flating pass; 8, D32 banked direction control valves; 9, bucket cylinder; 10, boom cylinder; 11, scraper bowl operating grip; 12, swing arm operating grip.
The specific embodiment
Embodiment 1: this control system comprises: double-united oil pump 1, safety valve 2, pilot-actuated valve group 3, operating grip 4, controller 5, swing arm alignment sensor 6, bucket flat pass sensor 7, D32 banked direction control valves 8, bucket cylinder 9, boom cylinder 10, scraper bowl operating grip 11 and swing arm operating grip 12, the oil-out of an oil pump of double-united oil pump 1 is connected with pilot-actuated valve group 3 input ports by safety valve 2, operating grip 4, swing arm position are decided sensor 6 and are connected with the input of controller 5 with the bucket sensor 7 of flating pass, and the output of controller 5 is connected with the control end of pilot-actuated valve group 3; The output of pilot-actuated valve group 3 is connected with the input of D32 banked direction control valves 8, another oil pump of double-united oil pump 1 is connected with the input of D32 banked direction control valves 8, the output of D32 banked direction control valves 8 is connected with boom cylinder 10 with bucket cylinder 9, D32 banked direction control valves 8 is connected with fuel tank by radiator, and the oil absorbing end of double-united oil pump 1 is by the strainer connected tank.
Described controller is a computer control module, buys from market.
Control method is: 1, offer the different control signal of computer control module by the different position of operating grip; 2, computer control module is amplified the corresponding proportion electro-magnet of rear drive with different control signals; 3, electro-hydraulic proportional reducing valve output control corresponding pressure oil, simultaneous computer control module are according to the switch of different operating handle signal controlling solenoid operated directional valve, thus the flow direction of the pilot pressure oil of control reducing valve output; 4, moving of the corresponding spool of pilot pressure oil control D32 banked direction control valves, the flow direction of control working connection pressure oil, and then the control of realization equipment; 5, the swing arm alignment sensor is used to set the position of moved arm lifting, and constantly detects the swing arm location transmission and give controller, is convenient to real-time monitoring, realizes the swing arm automatic positioning function; 6, scraper bowl is set level and is automatically replied the spading state when sensor is used for entering the spading position after scraper bowl unloads; 7, thick/smart mode-conversion switch is in when disconnecting, and is quick mode; When closed is the accurate operation pattern, and this moment, the output pwm signal dutycycle was less, and controlled pressure is less, and promptly control ratio reducing valve output pressure is less, and the major loop flow diminishes accordingly.
The concrete course of work: pulling swing arm operating grip 12 moves backward, the handle angle sensor is handled control signal via controller 5 and is transferred to pilot valve group 3, pilot valve group 3 control guide oil sources enter the a2 mouth of D32 banked direction control valves 8, make the commutation of swing arm reversal valve, boom cylinder 10 rodless cavity oil-feeds, swing arm rises.Handle swing arm handle 12 and move forward, handle angle sensor opposite control signal when sending and rising with swing arm, guide's oil sources enters the b2 mouth of D32 banked direction control valves 8, the commutation of swing arm reversal valve, the rod chamber oil-feed of boom cylinder 10, the decline of control swing arm.Guide's reducing valve output pressure and handle input angle signal are proportional, and guide's reducing valve output pressure is big more, and the displacement of control main valve change-over valve core is big more, and the flow that main valve passes through is big more, and swing arm speed is fast more.Promote swing arm handle 12 forward to maximum position, the handle angle sensor sends unsteady working signal, controller 8 places the maximum pressure output state with pilot valve group 3, output pressure control D32 valve 8 is in swing arm decline operating mode, the hydraulic control one-way valve reverse-conducting of the two position two-way valve control D32 valve 8 in the pilot valve group 3, the upper and lower cavity of boom cylinder 10 is by the one way valve conducting, and swing arm is in unsteady operating mode.Handle 12 is return meta, and swing arm is parked in and limits the position.
Pulling scraper bowl operating grip 11 moves backward, after handle angle sensor output signal of telecommunication via controller 5 is handled, the pilot pressure that 3 outputs of control pilot valve are directly proportional with it enters the a1 mouth of D32 banked direction control valves 8, thereby the scraper bowl control valve commutation of control D32 banked direction control valves 8, make the rodless cavity oil-feed of bucket cylinder 9, the control scraper bowl is turned over.Promote scraper bowl operating grip 11 forward, after handle angle sensor output signal of telecommunication via controller 5 is handled, the pilot pressure that 3 outputs of control pilot valve are directly proportional with it enters the b1 mouth of D32 banked direction control valves 8, thereby the scraper bowl control valve commutation of control D32 banked direction control valves 8, make the rod chamber oil-feed of bucket cylinder 9, the control scraper bowl overturns forward.Handle 11 is return meta, and scraper bowl is parked in and limits the position.
Pull back swing arm joystick 12, swing arm is risen to the position of needs, press downward moving arm position memory switch, controller 5 is remembered the swing arm position of this moment, as the upper limit position of setting.When operating swing arm handle 12 control swing arms once more and rise, if swing arm rises to the upper limit position of setting, the swing arm joystick is return meta automatically, and swing arm stops automatically and remains on this position.
Slightly/when smart mode-conversion switch is in disconnection, be quick mode; When closed is the accurate operation pattern, and this moment, the output pwm signal dutycycle was less, and controlled pressure (proportional pressure-reducing valve output pressure) is less, and the major loop flow diminishes accordingly, reaches the purpose of accurate operation.
Claims (3)
1. loader electro-hydraulic proportional control system, it is characterized in that: this control system comprises double-united oil pump, safety valve, the pilot-actuated valve group, operating grip, controller, the swing arm alignment sensor, the sensor of flating pass struggles against, the D32 banked direction control valves, bucket cylinder, boom cylinder, scraper bowl operating grip and swing arm operating grip, the oil-out of an oil pump of double-united oil pump is connected with pilot-actuated valve group input port by safety valve, operating grip, the swing arm position is decided sensor and is connected with the input of computer control module with the bucket sensor of flating pass, and the output of computer control module is connected with the control end of pilot-actuated valve group; The output of pilot-actuated valve group is connected with the input of D32 banked direction control valves, another oil pump of double-united oil pump is connected with the input of D32 banked direction control valves, the output of D32 banked direction control valves is connected with boom cylinder with bucket cylinder, the D32 banked direction control valves is connected with fuel tank by radiator, and the oil absorbing end of double-united oil pump is by the strainer connected tank.
2. loader electro-hydraulic proportional control system according to claim 1 is characterized in that: described controller is a computer control module.
3. utilize the control method of loader electro-hydraulic proportional control system, it is characterized in that: control method is: 1, offer the different control signal of computer control module by the different position of operating grip; 2, computer control module is amplified the corresponding proportion electro-magnet of rear drive with different control signals; 3, electro-hydraulic proportional reducing valve output control corresponding pressure oil, simultaneous computer control module are according to the switch of different operating handle signal controlling solenoid operated directional valve, thus the flow direction of the pilot pressure oil of control reducing valve output; 4, moving of the corresponding spool of pilot pressure oil control D32 banked direction control valves, the flow direction of control working connection pressure oil, and then the control of realization equipment; 5, the swing arm alignment sensor is used to set the position of moved arm lifting, and constantly detects the swing arm location transmission and give controller, is convenient to real-time monitoring, realizes the swing arm automatic positioning function; 6, scraper bowl is set level and is automatically replied the spading state when sensor is used for entering the spading position after scraper bowl unloads; 7, thick/smart mode-conversion switch is in when disconnecting, and is quick mode; When closed is the accurate operation pattern, and this moment, the output pwm signal dutycycle was less, and controlled pressure is less, and promptly control ratio reducing valve output pressure is less, and the major loop flow diminishes accordingly.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010241656 CN101936018A (en) | 2010-07-26 | 2010-07-26 | Electro-hydraulic proportion control system of loader |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010241656 CN101936018A (en) | 2010-07-26 | 2010-07-26 | Electro-hydraulic proportion control system of loader |
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| CN101936018A true CN101936018A (en) | 2011-01-05 |
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| CN 201010241656 Pending CN101936018A (en) | 2010-07-26 | 2010-07-26 | Electro-hydraulic proportion control system of loader |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102330720A (en) * | 2011-03-17 | 2012-01-25 | 陈海波 | Parameter dynamic matching control system between multi-way reversing valve and hydraulic oil cylinder |
| CN102535571A (en) * | 2012-02-17 | 2012-07-04 | 上海三一重机有限公司 | System and method of regeneration control based on double spools for hydraulic excavator |
| CN102730589A (en) * | 2012-07-11 | 2012-10-17 | 上海中联重科桩工机械有限公司 | Winding plant as well as hydraulic circuit, rotary drilling rig and engineering machine thereof |
| CN103334463A (en) * | 2013-05-24 | 2013-10-02 | 龙工(上海)机械制造有限公司 | Electro-hydraulic proportional control system and method of working device of loader |
| CN105155611A (en) * | 2015-08-27 | 2015-12-16 | 徐工集团工程机械股份有限公司科技分公司 | Intelligent control system of fixed-displacement hydraulic system for loader |
| CN105570491A (en) * | 2014-10-17 | 2016-05-11 | 徐工集团工程机械股份有限公司 | Load-sensitive multiway valve, load-sensitive system and excavator |
| CN106232905A (en) * | 2014-04-15 | 2016-12-14 | 沃尔沃建造设备有限公司 | Travel controlling system and control method thereof for engineering equipment |
| CN106315411A (en) * | 2016-10-27 | 2017-01-11 | 安徽柳工起重机有限公司 | Speed control system of automobile crane |
| CN106761660A (en) * | 2016-12-27 | 2017-05-31 | 中铁工程装备集团有限公司 | Rock drill automatic rollback control system and its control method |
| CN107934785A (en) * | 2017-12-18 | 2018-04-20 | 中车兰州机车有限公司 | Multichannel valve group electro-hydraulic proportional control system and crane |
| CN109854570A (en) * | 2019-01-07 | 2019-06-07 | 苏州瑞奇安机电科技有限公司 | A kind of oil suction decompressor and oil suction depressurized system |
| CN111836934A (en) * | 2018-04-27 | 2020-10-27 | 株式会社小松制作所 | Control device for loading machine and control method for loading machine |
| CN112594240A (en) * | 2020-12-24 | 2021-04-02 | 山推工程机械股份有限公司 | Working device hydraulic system, control method and electric loader |
| CN112682373A (en) * | 2020-12-29 | 2021-04-20 | 山推工程机械股份有限公司 | Hydraulic system, control method and engineering vehicle |
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Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102330720B (en) * | 2011-03-17 | 2014-05-28 | 昆山航天智能技术有限公司 | Parameter dynamic matching control system between multi-way reversing valve and hydraulic oil cylinder |
| CN102330720A (en) * | 2011-03-17 | 2012-01-25 | 陈海波 | Parameter dynamic matching control system between multi-way reversing valve and hydraulic oil cylinder |
| CN102535571A (en) * | 2012-02-17 | 2012-07-04 | 上海三一重机有限公司 | System and method of regeneration control based on double spools for hydraulic excavator |
| CN102730589A (en) * | 2012-07-11 | 2012-10-17 | 上海中联重科桩工机械有限公司 | Winding plant as well as hydraulic circuit, rotary drilling rig and engineering machine thereof |
| CN102730589B (en) * | 2012-07-11 | 2014-08-27 | 上海中联重科桩工机械有限公司 | Winding plant as well as hydraulic circuit, rotary drilling rig and engineering machine thereof |
| CN103334463A (en) * | 2013-05-24 | 2013-10-02 | 龙工(上海)机械制造有限公司 | Electro-hydraulic proportional control system and method of working device of loader |
| CN106232905A (en) * | 2014-04-15 | 2016-12-14 | 沃尔沃建造设备有限公司 | Travel controlling system and control method thereof for engineering equipment |
| CN105570491B (en) * | 2014-10-17 | 2018-03-06 | 徐工集团工程机械股份有限公司 | Load sensing multi-way valve, load sensitive system and excavator |
| CN105570491A (en) * | 2014-10-17 | 2016-05-11 | 徐工集团工程机械股份有限公司 | Load-sensitive multiway valve, load-sensitive system and excavator |
| CN105155611A (en) * | 2015-08-27 | 2015-12-16 | 徐工集团工程机械股份有限公司科技分公司 | Intelligent control system of fixed-displacement hydraulic system for loader |
| CN105155611B (en) * | 2015-08-27 | 2018-02-02 | 徐工集团工程机械股份有限公司科技分公司 | A kind of loading machine paced work hydraulic system Intelligent control system |
| CN106315411A (en) * | 2016-10-27 | 2017-01-11 | 安徽柳工起重机有限公司 | Speed control system of automobile crane |
| CN106761660A (en) * | 2016-12-27 | 2017-05-31 | 中铁工程装备集团有限公司 | Rock drill automatic rollback control system and its control method |
| CN106761660B (en) * | 2016-12-27 | 2023-02-03 | 中铁工程装备集团有限公司 | Automatic retraction control system and control method for rock drill |
| CN107934785A (en) * | 2017-12-18 | 2018-04-20 | 中车兰州机车有限公司 | Multichannel valve group electro-hydraulic proportional control system and crane |
| CN111836934A (en) * | 2018-04-27 | 2020-10-27 | 株式会社小松制作所 | Control device for loading machine and control method for loading machine |
| US11821168B2 (en) | 2018-04-27 | 2023-11-21 | Komatsu Ltd. | Control device for loading machine and control method for loading machine |
| CN109854570A (en) * | 2019-01-07 | 2019-06-07 | 苏州瑞奇安机电科技有限公司 | A kind of oil suction decompressor and oil suction depressurized system |
| CN109854570B (en) * | 2019-01-07 | 2023-09-26 | 苏州瑞奇安机电科技有限公司 | Oil absorption pressure reducing device and oil absorption pressure reducing system |
| CN112594240A (en) * | 2020-12-24 | 2021-04-02 | 山推工程机械股份有限公司 | Working device hydraulic system, control method and electric loader |
| CN112594240B (en) * | 2020-12-24 | 2023-02-03 | 山推工程机械股份有限公司 | Hydraulic system of working device, control method and electric loader |
| CN112682373A (en) * | 2020-12-29 | 2021-04-20 | 山推工程机械股份有限公司 | Hydraulic system, control method and engineering vehicle |
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Application publication date: 20110105 |