AU2011287925A1 - Hydraulic preheating apparatus for hydraulic oil coolers in a large hydraulic excavator - Google Patents

Hydraulic preheating apparatus for hydraulic oil coolers in a large hydraulic excavator Download PDF

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Publication number
AU2011287925A1
AU2011287925A1 AU2011287925A AU2011287925A AU2011287925A1 AU 2011287925 A1 AU2011287925 A1 AU 2011287925A1 AU 2011287925 A AU2011287925 A AU 2011287925A AU 2011287925 A AU2011287925 A AU 2011287925A AU 2011287925 A1 AU2011287925 A1 AU 2011287925A1
Authority
AU
Australia
Prior art keywords
hydraulic oil
hydraulic
oil cooler
pressure
outlet box
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.)
Abandoned
Application number
AU2011287925A
Inventor
Wilfried Busse
Reinhard Emminger
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.)
Caterpillar Global Mining HMS GmbH
Original Assignee
Caterpillar Global Mining HMS GmbH
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 Caterpillar Global Mining HMS GmbH filed Critical Caterpillar Global Mining HMS GmbH
Publication of AU2011287925A1 publication Critical patent/AU2011287925A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F27/00—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus
    • F28F27/02—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus for controlling the distribution of heat-exchange media between different channels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M5/00—Heating, cooling, or controlling temperature of lubricant; Lubrication means facilitating engine starting
    • F01M5/002—Cooling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M5/00—Heating, cooling, or controlling temperature of lubricant; Lubrication means facilitating engine starting
    • F01M5/005—Controlling temperature of lubricant
    • F01M5/007—Thermostatic control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0427—Heating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/053—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight
    • F28D1/05316—Assemblies of conduits connected to common headers, e.g. core type radiators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2250/00—Arrangements for modifying the flow of the heat exchange media, e.g. flow guiding means; Particular flow patterns
    • F28F2250/06—Derivation channels, e.g. bypass
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2265/00—Safety or protection arrangements; Arrangements for preventing malfunction
    • F28F2265/12—Safety or protection arrangements; Arrangements for preventing malfunction for preventing overpressure

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Fluid Mechanics (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Component Parts Of Construction Machinery (AREA)

Abstract

An apparatus for preheating hydraulic oil which is located at low temperatures in at least one air-cooled hydraulic oil cooler, wherein at least one hydraulic oil cooler is arranged outside an engine compartment, in particular of a large hydraulic excavator, characterized in that the oil, in particular hot oil, coming from a tank is fed to the inlet box of the hydraulic oil cooler and is passed on via connecting lines and an interposed pressure relief valve or a non-return valve to the outlet box of at least one hydraulic oil cooler, wherein the outlet box and the cold oil located therein can be heated and fed to the tank.

Description

WO 2012/016668 PCT/EP201l/003823 Hydraulic preheating apparatus for hydraulic oil coolers in a large hydraulic excavator The invention relates to a device for preheating 5 hydraulic oil as per the preamble of the first claim. In a large hydraulic excavator, the abovementioned hydraulic oil coolers are normally arranged outside the engine compartment. Owing to said arrangement, when the 10 excavator is used in cold ambient air, the problem arises that, after standstill periods, such as for example upon the initial start-up of the appliance or after repair or servicing work, the hydraulic oil becomes viscous to the point of solidification; this 15 consequently leads to damage in hydraulic oil coolers arranged outside the engine bay and thus to downtime of the large hydraulic excavator. An air-cooled hydraulic oil cooler is often constructed 20 from fins through which the oil flows, fins through which air passes, and two collecting boxes for the oil flowing in and flowing out. If a large hydraulic excavator is started up from a 25 standstill at low temperatures, the hydraulic pumps warm up slowly after the starting of the engines. At the same time, the oil in the hydraulic tank, in the lines within the pump chamber and in the main components is heated, wherein the oil in the hydraulic 30 tank is heated to operating temperature quickly. When the oil situated in the hydraulic tank has reached its operating temperature, the temperature sensor mounted in the oil tank activates the fan drive of the hydraulic oil cooler and the cooling oil pump. As a 35 result of the narrow fins in the hydraulic oil cooler and the mounting of the cooler outside the engine bay, the hydraulic oil situated in the oil cooler has not yet undergone any increase in temperature or has not WO 2012/016668 - 2 - PCT/EP2011/003823 yet undergone a sufficient increase in temperature. As a result of the situation that has now arisen, in which the oil in the hydraulic tank has reached a temperature which necessitates cooling of the oil but the oil 5 situated in the fins of the oil cooler is still cold and cannot be flushed out quickly enough, the back pressure in the system can exceed the burst pressure of the cooler and thus lead to damage to the hydraulic oil cooler. 10 From experience, the inlet and outlet boxes of the hydraulic oil coolers described further above each have one connector. The oil to be cooled is conducted into the inlet box, from which said oil flows vertically 15 through the fins of the hydraulic oil cooler to the outlet box. The oil flowing into the outlet box is supplied via the outlet connector to the hydraulic tank. Air passes horizontally around the fins of the hydraulic oil cooler during operation. 20 DE 197 50 814 Al discloses a heat exchanger, in particular oil cooler, of the type having at least two mutually separate flow ducts for different media, said flow ducts being penetrated by ducts for the inflow and 25 outflow of a medium, and having corresponding connections on said ducts to the ducts for the other medium, and also having a cover which is sealed off in the direction of the heat exchanger and which forms a flow duct and which includes at least one control valve 30 by means of which the temperature-dependent throughflow can be controlled. DE 699 21 618 T2 presents a cooling and heating system for a machine, for example a wheeled loader or tipper 35 truck, having a main line which is arranged so as to contain a fluid, having a first heat exchanger which is connected to the main line, and having a charge-air WO 2012/016668 - 3 - PCT/EP2011/003823 cooler for cooling compressed charge air for an internal combustion engine which is arranged in the machine, wherein the charge-air cooler is connected to the main line, wherein a second heat exchanger is 5 connected to the main line downstream of the charge-air cooler, to which second heat exchanger a line for hydraulic liquid is connected such that heat can be transferred between the fluid in the main line and the hydraulic liquid in the line for hydraulic liquid. 10 The invention is based on the object of quickly heating solidified hydraulic oil situated in the fins of the hydraulic oil cooler, in particular of a large hydraulic excavator, by means of a bypass flow in order 15 to prevent the abovementioned damage situation. Said object is achieved in that the in particular hot oil passing from a tank is supplied to the inlet box of the hydraulic oil cooler and is conducted onward via 20 connecting lines and an interposed pressure-limiting valve or a check valve to the outlet box of at least one hydraulic oil cooler, wherein the outlet box and the cold oil situated therein can be heated and supplied to the tank. 25 Advantageous refinements of the subject matter of the application emerge from the subclaims. If the oil situated in the fins of the oil cooler is 30 still cold, the preheated oil which flows into the inlet box via the first connector and which is at operating pressure is conducted through the inlet box, past the oil cooler fins to the second connector of the inlet box, and onward in the connecting line to the 35 outlet box. A pressure-limiting valve is provided in said line. The pressure port of said valve is connected via the line to the inlet box, and the tank port is WO 2012/016668 - 4 - PCT/EP2011/003823 connected via a further line to the outlet box of the hydraulic oil cooler. When the preheated oil which is under pressure now 5 flows via the first connector into the inlet box of the hydraulic oil cooler, a pressure builds up if the oil situated in the fins of the hydraulic oil cooler is cold, because the cold oil cannot immediately be forced out of the fins. Via the second connector of the inlet 10 box, the preheated oil situated in the inlet box is now supplied via the second connector to the pressure limiting valve. If a preset pressure, which lies below the maximum operating pressure of the hydraulic oil cooler, is exceeded in the pressure-limiting valve, the 1S valve opens and permits the throughf low of oil flowing from the inlet box to the outlet box. As flow passes through the pressure-limiting valve, the oil is heated further and is supplied, according to the invention, to the first connector of the outlet box. The oil is 20 supplied via the second connector from the outlet box to the tank. The hot oil from the hydraulic tank is thus under pressure at the connector of the inlet box of the 25 hydraulic oil cooler. At the same time, by means of the device described above, hydraulic oil is heated further and is present in the outlet box of the hydraulic cooler. The cooler is thereby heated to such an extent that, with the rising pressure, the still-blocked fins 30 can be flushed out. As a result, the back pressure in the system falls, and the pressure-limiting valve closes. The hydraulic oil cooler then operates in the normal state. 35 Instead of the pressure-limiting valve, use may also be made of an in particular spring-preloaded check valve.
WO 2012/016668 - 5 - PCT/EP2011/003823 The subject matter of the invention is illustrated, on the basis of an exemplary embodiment, in the drawing and will be described below. In the drawing: 5 figure 1 shows the present design (prior art); figure 2 is an illustration of the preheating with a pressure-limiting valve; 10 figure 3 is an illustration of the preheating with a spring-preloaded check valve. Figure 1 shows the prior art in the form of a diagrammatic sketch. By means of a temperature sensor 15 1, which is arranged in the tank 2, and control electronics 3 (not illustrated in any more detail), hydraulic oil is conducted by means of a delivery pump 4 and via a control valve 5 from the tank 2 into the inlet box 6 of the hydraulic oil cooler 7. The 20 hydraulic oil builds up a pressure in the fins 7' of the hydraulic oil cooler 7 and forces the cold oil present there into the outlet box 8 of the hydraulic oil cooler 7, from which said oil is conducted via the line 9 to the tank 2. 25 Figure 2 shows, in the form of a diagrammatic sketch, the device according to the invention for preheating cold hydraulic oil which is present in the fins 7' of a hydraulic oil cooler 7. Identical components are 30 denoted by the same reference numerals. It is possible to see the hydraulic oil cooler 7 with the inlet box 6 and outlet box 8, a pressure-limiting valve 13 and the connecting lines 14, 15 from the inlet box 6 to the pressure-limiting valve 13 and from the pressure 35 limiting valve 13 to the outlet box 8. By means of a temperature sensor 1, which is arranged in the tank 2, and control electronics 3 (not illustrated in any more WO 2012/016668 - 6 - PCT/EP2011/003823 detail), oil is supplied by means of a delivery pump 4 and via a control valve 5 from the hydraulic tank 2 to the connector 10 of the inlet box 6 of the hydraulic oil cooler 7. When the oil is cold and the pressure set 5 at the pressure-limiting valve 13 is exceeded, the oil present in the inlet box 6 flows via the connector 11 of the inlet box 6 and via the line 14 to the pressure limiting valve 13, and flows onward from there via the line 15 to the connector 16 of the outlet box 8 of the 10 hydraulic oil cooler 7. The heated oil is supplied via the connector 17 of the outlet box 8 of the hydraulic oil cooler 7 back to the tank 2 via the line 9. Figure 3 shows, in the form of a diagrammatic sketch, 15 the device according to the invention for preheating cold hydraulic oil which is present in the fins 7' of a hydraulic oil cooler 7, wherein in this case, a spring preloaded check valve 18 is used instead of the pressure-limiting valve 13. The function in this case 20 corresponds to that of figure 2.
WO 2012/016668 - 7 - PCT/EP2011/003823 List of reference numerals 1 Temperature sensor 2 Tank 5 3 Control electronics 4 Delivery pump 5 Control valve 6 Inlet box of the hydraulic oil cooler 7 Hydraulic oil cooler 10 7' Fins 8 Outlet box of the hydraulic oil cooler 9 Line 10 Connector of the inlet box 11 Connector of the inlet box 15 13 Pressure-limiting valve 14 Connecting line 15 Connecting line 16 Connector of the outlet box 17 Connector of the outlet box 20 18 Spring-preloaded check valve

Claims (5)

1. A device for preheating hydraulic oil which is situated, at low temperatures, in at least one 5 air-cooled hydraulic oil cooler (7), wherein at least one hydraulic oil cooler (7) is arranged outside an engine compartment, in particular of a large hydraulic excavator, characterized in that the in particular hot oil passing from a tank (2) 10 is supplied to the inlet box (6) of the hydraulic oil cooler (7) and is conducted onward via connecting lines (14, 15) and an interposed pressure-limiting valve (13) or a check valve (18) to the outlet box (8) of at least one hydraulic 15 oil cooler (7), wherein the outlet box (8) and the cold oil situated therein can be heated and supplied to the tank (2).
2. The device as claimed in claim 1, characterized in 20 that the oil flowing from the inlet box (6) of the hydraulic oil cooler (7) to the pressure-limiting valve (13), or the check valve (18), and from there to the outlet box (8) of the hydraulic oil cooler (7) is raised from a low temperature level 25 to a higher temperature level before it passes into the outlet box (8) of the hydraulic oil cooler (7).
3. The device as claimed in claim 1 or 2, 30 characterized in that the pressure-limiting valve (13) opens the line (15) to the outlet box (8) of the hydraulic oil cooler (7) when a preset response pressure is reached, wherein the preset response pressure lies below the admissible 35 operating pressure of the hydraulic oil cooler (7). WO 2012/016668 - 9 - PCT/EP2011/003823
4. The device as claimed in one of claims 1 to 3, characterized in that, when the response pressure preset at the pressure-limiting valve (13, 18) is undershot, the line (15) to the outlet box (8) of 5 the hydraulic oil cooler (7) is closed.
5. The device as claimed in one of claims 1 to 4, characterized in that a spring-preloaded check valve (18) can be used instead of the pressure 10 limiting valve (13).
AU2011287925A 2010-08-04 2011-07-29 Hydraulic preheating apparatus for hydraulic oil coolers in a large hydraulic excavator Abandoned AU2011287925A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE202010011010U DE202010011010U1 (en) 2010-08-04 2010-08-04 Hydraulic preheater for hydraulic oil cooler in a large hydraulic excavator
DE202010011010.6 2010-08-04
PCT/EP2011/003823 WO2012016668A1 (en) 2010-08-04 2011-07-29 Hydraulic preheating apparatus for hydraulic oil coolers in a large hydraulic excavator

Publications (1)

Publication Number Publication Date
AU2011287925A1 true AU2011287925A1 (en) 2013-02-28

Family

ID=43049765

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2011287925A Abandoned AU2011287925A1 (en) 2010-08-04 2011-07-29 Hydraulic preheating apparatus for hydraulic oil coolers in a large hydraulic excavator

Country Status (6)

Country Link
US (1) US20130213633A1 (en)
EP (1) EP2601390A1 (en)
CN (1) CN103140654B (en)
AU (1) AU2011287925A1 (en)
DE (1) DE202010011010U1 (en)
WO (1) WO2012016668A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103398626B (en) * 2013-07-26 2016-01-20 江苏高博智融科技有限公司 A kind of heat exchanger with ring sound
US10436529B1 (en) * 2018-08-23 2019-10-08 William T. Holley, Jr. Hydraulic fluid coolers
GB2585908B (en) * 2019-07-23 2023-08-23 Bamford Excavators Ltd Working Machine
US10859203B1 (en) * 2020-03-12 2020-12-08 American Jereh International Corporation High-low pressure lubrication system for high-horsepower plunger pump

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JP4931955B2 (en) * 2009-04-06 2012-05-16 日立建機株式会社 Hydraulic circuit device of excavator

Also Published As

Publication number Publication date
CN103140654A (en) 2013-06-05
DE202010011010U1 (en) 2010-11-04
EP2601390A1 (en) 2013-06-12
WO2012016668A1 (en) 2012-02-09
US20130213633A1 (en) 2013-08-22
CN103140654B (en) 2016-03-02

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Legal Events

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MK4 Application lapsed section 142(2)(d) - no continuation fee paid for the application