EP1741893A1 - Système de commande pour ventilateur de refroidissement - Google Patents

Système de commande pour ventilateur de refroidissement Download PDF

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Publication number
EP1741893A1
EP1741893A1 EP06116237A EP06116237A EP1741893A1 EP 1741893 A1 EP1741893 A1 EP 1741893A1 EP 06116237 A EP06116237 A EP 06116237A EP 06116237 A EP06116237 A EP 06116237A EP 1741893 A1 EP1741893 A1 EP 1741893A1
Authority
EP
European Patent Office
Prior art keywords
motor
fluid
speed
temperature
coolant
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP06116237A
Other languages
German (de)
English (en)
Inventor
Yoshimi KOBELCO CONSTR. MACHIN. CO. LTD. Saotome
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kobelco Construction Machinery Co Ltd
Original Assignee
Kobelco Construction Machinery Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kobelco Construction Machinery Co Ltd filed Critical Kobelco Construction Machinery Co Ltd
Publication of EP1741893A1 publication Critical patent/EP1741893A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/02—Controlling of coolant flow the coolant being cooling-air
    • F01P7/04—Controlling of coolant flow the coolant being cooling-air by varying pump speed, e.g. by changing pump-drive gear ratio
    • F01P7/044—Controlling of coolant flow the coolant being cooling-air by varying pump speed, e.g. by changing pump-drive gear ratio using hydraulic drives
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2025/00—Measuring
    • F01P2025/08—Temperature
    • F01P2025/34—Heat exchanger incoming fluid temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2025/00—Measuring
    • F01P2025/08—Temperature
    • F01P2025/40—Oil temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2025/00—Measuring
    • F01P2025/08—Temperature
    • F01P2025/52—Heat exchanger temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2060/00—Cooling circuits using auxiliaries
    • F01P2060/04—Lubricant cooler

Definitions

  • the present invention relates to controlling systems for cooling fans that are driven by hydraulic motors.
  • Japanese Patent No. 3238775 discusses a technique for preventing a waste of energy in a driving system of a hydraulic motor that rotates a cooling fan of an engine cooling device and a working-oil cooling device disposed in a hydraulic excavator. Specifically, this is achieved by switching the rotational speed of the hydraulic motor between high and low speed modes in accordance with the temperature of fluid to be cooled.
  • the motor is rotated at high speed when the temperature values of coolant water and working oil for the motor are higher than a predetermined temperature value, whereas the motor is rotated at low speed when these temperature values are lower than the predetermined temperature value.
  • the motor speed may change drastically within that period depending on the content (load) of the work. This may cause a drastic change in fan noise in response to each changing of the motor speed, giving an operator a feeling of insecurity and unpleasantness.
  • a controlling system for a cooling fan according to the present invention has the following basic structure.
  • the controlling system for the cooling fan includes a fluid-pressure motor for driving the cooling fan; a fluid-pressure pump functioning as a fluid-pressure source for the fluid-pressure motor; temperature sensors for detecting temperature values of multiple kinds of fluids to be cooled; and motor-speed controlling means for controlling a rotational speed of the fluid-pressure motor.
  • the motor-speed controlling means determines a target motor speed value by selecting a higher one of required motor speed values respectively corresponding to the fluids and controls the fluid-pressure motor so that the motor speed thereof reaches the target motor speed value, each of the required motor speed values being determined from the temperature value of the corresponding fluid detected by the corresponding temperature sensor on the basis of a characteristic preliminarily determined by a temperature-versus-motor-speed relationship for the corresponding fluid, the characteristic being set for each kind of fluid.
  • the temperature-versus-motor-speed characteristics are preliminarily determined respectively for the multiple kinds of fluids to be cooled.
  • the fluid-pressure motor is thus controlled so that the motor speed thereof reaches the target value. Accordingly, in contrast to the related art in which the speed control is performed by selecting between two speed modes of high speed and low speed, a speed control operation according to the present invention allows for smaller speed changes in association with changes in fluid temperature, that is, a required cooling capability.
  • this reduces a drastic change in fan noise and stabilizes the operating power by reducing a drastic fluctuation of consumption power for driving the cooling fan.
  • a description below is directed to an example in which the present invention is applied to a hydraulic excavator that is driven hydraulically with, for example, fluid pressure.
  • a hydraulic excavator is equipped with, for example, an engine cooling device for cooling an engine; a working-oil cooling device for cooling working oil that is used for actuating a hydraulic actuator serving as a fluid-pressure actuator; and a cabin cooling device for cooling the interior of a cabin.
  • these cooling devices are individually provided with cooling fans, or are provided with a common cooling fan.
  • a cooling fan is rotated by a hydraulic motor serving as a fluid-pressure motor that is driven hydraulically with a hydraulic pump serving as a fluid-pressure pump.
  • a controlling system for a cooling fan according to the present invention is used for such a cooling fan.
  • water is used as a coolant
  • working oil is used as a working fluid for driving the fluid-pressure actuator
  • a radiator is used as a coolant cooler for cooling the coolant.
  • Fig. 1 illustrates an example in which a radiator 2 serving as the engine cooling device and an oil cooler 3 serving as the working-oil cooling device are cooled with a single cooling fan 1. Therefore, in this example, fluids to be cooled include working oil and coolant water for the radiator 2.
  • a hydraulic motor 4 is provided for driving the cooling fan 1
  • a variable-displacement hydraulic pump 5 is provided as a hydraulic source for the hydraulic motor 4.
  • a controller 6 and a pump regulator 7 define speed controlling means for controlling the rotational speed of the hydraulic motor 4. In some cases, the rotational speed will be referred to as a fan speed hereinafter.
  • the pump regulator 7 is actuated in response to a command signal from the controller 6, by which the capacity of the hydraulic pump 5 is adjusted.
  • the pump pressure is controlled, thereby changing the motor speed of the hydraulic motor 4.
  • a water temperature sensor 8 and an oil temperature sensor 9 are also provided.
  • the water temperature sensor 8 serves as a coolant temperature sensor that detects a temperature value of the radiator coolant-water (which will be referred to as a water temperature value hereinafter).
  • the oil temperature sensor 9 serves as a working-fluid temperature sensor that detects a temperature value of the working oil (which will be referred to as an oil temperature value hereinafter).
  • the water and oil temperature values detected by the sensors 8 and 9, respectively, are input to the controller 6.
  • Reference character T in Fig. 1 indicates a tank.
  • a characteristic of water-temperature versus required-motor-speed V1 with respect to the water temperature (i.e. a cooling capability corresponding to the fan speed of the cooling fan 1) shown in Fig. 2 and a characteristic of oil-temperature versus required-motor-speed V2 with respect to the oil temperature shown in Fig. 3 are preliminarily set and stored in the controller 6. Accordingly, based on these characteristics, a required motor speed value V1 and a required motor speed value V2 with respect to the water and oil temperature values respectively detected by the water temperature sensor 8 and the oil temperature sensor 9 can be determined.
  • the controller 6 selects the higher one of the values and controls the speed of the hydraulic motor 4 via the hydraulic pump 5 on the basis of the selected required motor speed value as a target value.
  • a required motor speed value with respect to the water temperature value is 800 rpm and a required motor speed value with respect to the oil temperature value is 1,180 rpm. Therefore, the higher value 1,180 rpm is selected as a target value. Accordingly, the controller 6 controls the motor speed of the hydraulic motor 4 towards the target value of 1,180 rpm.
  • the speed control according to the present invention allows for smaller speed changes in association with changes in fluid temperature (required cooling capability) since the motor speed can be changed continuously in accordance with a continuous change in the water temperature or the oil temperature.
  • the motor speed is controlled on the basis of a target value, which is the higher one of the required motor speed values corresponding to the detected water and oil temperature values, a proper speed controlling can be achieved without over-speeding or under-speeding.
  • this reduces a drastic change in fan noise and stabilizes the operating power by reducing a drastic fluctuation of an engine consumption power for driving the cooling fan 1.
  • Fig. 4 is a block diagram of an engine cooling device.
  • a cooling circuit 12 is provided with a cooling pump 10. Coolant water discharged from the cooling pump 10 passes through an engine (water jacket) 11 and enters the radiator 2. After being cooled, the coolant water returns to the cooling pump 10.
  • a thermostat 13 which is a valve that is openable and closeable depending on the water temperature, is disposed adjacent to an output side of the engine 11.
  • the thermostat 13 When the water temperature is equal to or less than a predetermined temperature value and is thus in a low temperature state, the thermostat 13 is closed such that the cooling circuit 12 is cut off. In this state, the coolant water circulates around a circulation path 14.
  • the water temperature sensor 8 is provided in the cooling circuit 12 that surrounds the circulation path 14, such that the water temperature sensor 8 detects a water temperature value in the vicinity of its position.
  • the water temperature sensor 8 will detect a water temperature value that is increased in the course of circulation. This implies that a control operation for increasing the motor speed will be implemented regardless of the fact that the radiator water temperature to be lowered may still be low, thus resulting in an unnecessary control operation.
  • the water temperature is detected outside of the circulation path 14 (i.e. in the cooling circuit 12) in the first embodiment, as shown in Fig. 4.
  • the control operation may be performed solely in response to this certain water temperature value or higher. This means that it is not necessary to take into consideration lower water temperature values, whereby the control operation is simplified.
  • the thermostat 13 is closed until the water temperature reaches a predetermined temperature value, and when the water temperature reaches the predetermined temperature value in the course of the circulation of the coolant water around the circulation path 14, the thermostat 13 is opened, thereby allowing the coolant water to flow into the cooling circuit 12.
  • thermostat 13 is used as an automatic temperature-adjusting device in the first embodiment, other alternative types of automatic temperature-adjusting devices that are capable of adjusting the temperature by being opened at a predetermined water temperature value are also permissible.
  • the cooling effect may vary depending on the outside air temperature.
  • the higher the outside air temperature the lower the cooling effect, whereas the lower the outside air temperature, the higher the cooling effect.
  • the outside air temperature may also vary by several tens of degrees Celsius depending on location and season.
  • the fan function is set such that a proper cooling capability is attained even when the outside air temperature is at the highest.
  • controlling the motor speed simply on the basis of the water temperature and the oil temperature may possibly cause overcooling as a result of an excess cooling capability when the system is used in an environment where the outside air temperature is low.
  • the second embodiment is additionally provided with an air temperature sensor 15 for detecting an outside air temperature value.
  • an air temperature sensor 15 for detecting an outside air temperature value.
  • a solid line in Fig. 6 indicates a characteristic I corresponding to a case where the outside air temperature exceeds a predetermined temperature value
  • a dashed line in Fig. 6 indicates a characteristic II corresponding to a case where the outside air temperature is equal to or lower than the predetermined temperature value. Consequently, the motor speed is controlled by selecting one of the characteristics that corresponds to the detected outside air temperature value.
  • this inhibits overcooling when the system is used in an environment where the outside air temperature is low, thereby preventing a waste of energy.
  • Fig. 6 only shows the characteristics determined by the relationship between oil temperature and motor speed, characteristics determined by the relationship between water temperature and motor speed are set in a similar manner.
  • a plurality of cooling fans may be provided.
  • the control operation described above may be performed similarly for each of the hydraulic motors.
  • the hydraulic motors may be connected in series or in parallel.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Component Parts Of Construction Machinery (AREA)
  • Cooling, Air Intake And Gas Exhaust, And Fuel Tank Arrangements In Propulsion Units (AREA)
  • Fluid-Pressure Circuits (AREA)
EP06116237A 2005-07-06 2006-06-28 Système de commande pour ventilateur de refroidissement Withdrawn EP1741893A1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2005197664A JP2007016659A (ja) 2005-07-06 2005-07-06 冷却ファンの制御装置

Publications (1)

Publication Number Publication Date
EP1741893A1 true EP1741893A1 (fr) 2007-01-10

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP06116237A Withdrawn EP1741893A1 (fr) 2005-07-06 2006-06-28 Système de commande pour ventilateur de refroidissement

Country Status (4)

Country Link
US (1) US20070006824A1 (fr)
EP (1) EP1741893A1 (fr)
JP (1) JP2007016659A (fr)
CN (1) CN1891995A (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2282029A1 (fr) 2009-06-29 2011-02-09 Joseph Vögele AG Machine autoporteuse
DE102013205331A1 (de) * 2013-03-26 2014-10-02 Zf Friedrichshafen Ag Verfahren und Steuerungseinrichtung zum Betreiben eines Motorlüfters
CN112145276A (zh) * 2020-09-30 2020-12-29 郑州铁路职业技术学院 一种发动机的散热系统
SE2350701A1 (en) * 2023-06-09 2024-12-10 Scania Cv Ab A method and control arrangement for controlling operation of a fan in a cooling system of a vehicle

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US7395788B2 (en) * 2005-03-22 2008-07-08 Atlas Copco Rock Drills Ab Drill rig and a method for controlling a fan therein
KR100999608B1 (ko) * 2007-08-24 2010-12-08 기아자동차주식회사 Ｅｇｒ 냉각수 제어 시스템
CN101851941B (zh) * 2010-04-16 2012-02-29 山推工程机械股份有限公司 推土机风扇冷却控制系统
US8826654B2 (en) 2011-05-31 2014-09-09 Caterpillar Inc. Hydraulic fluid system
US8844279B2 (en) 2011-05-31 2014-09-30 Caterpillar Inc. Hydraulic fan circuit
JP2013209940A (ja) * 2012-03-30 2013-10-10 Hitachi Constr Mach Co Ltd 作業機械
CN103670655A (zh) * 2012-09-14 2014-03-26 上海创斯达热交换器有限公司 发动机冷却模块电子风扇控制装置及其工作方法
CN102878152B (zh) * 2012-10-12 2015-04-22 中联重科股份有限公司 液压系统的功率控制方法和控制装置与液压系统
CN103790686A (zh) * 2014-01-25 2014-05-14 中国北方车辆研究所 一种负载敏感式车用冷却风扇传动装置
US9523306B2 (en) * 2014-05-13 2016-12-20 International Engine Intellectual Property Company, Llc. Engine cooling fan control strategy
DE102014110231B3 (de) * 2014-07-21 2015-09-10 Nidec Gpm Gmbh Kühlmittelpumpe mit integrierter Regelung
US9406535B2 (en) * 2014-08-29 2016-08-02 Lam Research Corporation Ion injector and lens system for ion beam milling
US10393261B2 (en) * 2017-12-06 2019-08-27 Cnh Industrial America Llc High ambient temperature propulsion speed control of a self-propelled agricultural product applicator
CN112228204A (zh) * 2020-10-29 2021-01-15 四川邦立重机有限责任公司 抓料机、挖掘机自适应独立冷却方法及系统
US11813963B2 (en) 2021-02-25 2023-11-14 Ford Global Technologies, Llc Cooling method and system
CN114059615B (zh) * 2021-10-12 2023-03-31 中联重科土方机械有限公司 液压挖掘机散热控制方法、系统及液压挖掘机
CN114233460A (zh) * 2021-12-28 2022-03-25 徐州徐工矿业机械有限公司 一种工程机械独立散热控制系统及方法
CN114893286A (zh) * 2022-05-16 2022-08-12 雷沃工程机械集团有限公司 一种装载机双介质智能控温系统
CN119137358A (zh) * 2022-06-29 2024-12-13 日立建机株式会社 运输车辆

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3377023A (en) * 1966-02-01 1968-04-09 Caterpillar Tractor Co Discriminating variable speed control for multiple heat exchanger fan motors
EP0156078A1 (fr) * 1984-01-23 1985-10-02 Borg-Warner Corporation Système de contrôle de température pour moteur à combustion interne
US5165377A (en) * 1992-01-13 1992-11-24 Caterpillar Inc. Hydraulic fan drive system
WO2000039438A1 (fr) * 1998-12-30 2000-07-06 Case Corporation Systeme de refroidissement ameliore pour vehicule de chantier
US20010029907A1 (en) * 1999-12-17 2001-10-18 Algrain Marcelo C. Twin fan control system and method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2282029A1 (fr) 2009-06-29 2011-02-09 Joseph Vögele AG Machine autoporteuse
DE102013205331A1 (de) * 2013-03-26 2014-10-02 Zf Friedrichshafen Ag Verfahren und Steuerungseinrichtung zum Betreiben eines Motorlüfters
CN112145276A (zh) * 2020-09-30 2020-12-29 郑州铁路职业技术学院 一种发动机的散热系统
SE2350701A1 (en) * 2023-06-09 2024-12-10 Scania Cv Ab A method and control arrangement for controlling operation of a fan in a cooling system of a vehicle
US12590555B2 (en) 2023-06-09 2026-03-31 Scania Cv Ab Method and control arrangement for controlling operation of a fan in a cooling system of a vehicle

Also Published As

Publication number Publication date
US20070006824A1 (en) 2007-01-11
CN1891995A (zh) 2007-01-10
JP2007016659A (ja) 2007-01-25

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