Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/04—Features relating to lubrication or cooling or heating
  • F16H57/0412—Cooling or heating; Control of temperature
  • F16H57/0413—Controlled cooling or heating of lubricant; Temperature control therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/04—Features relating to lubrication or cooling or heating
  • F16H57/0434—Features relating to lubrication or cooling or heating relating to lubrication supply, e.g. pumps ; Pressure control
  • F16H57/0443—Features relating to lubrication or cooling or heating relating to lubrication supply, e.g. pumps ; Pressure control for supply of lubricant during tilt or high acceleration, e.g. problems related to the tilt or extreme acceleration of the transmission casing and the supply of lubricant under these conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/04—Features relating to lubrication or cooling or heating
  • F16H57/0456—Lubrication by injection; Injection nozzles or tubes therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/04—Features relating to lubrication or cooling or heating
  • F16H57/048—Type of gearings to be lubricated, cooled or heated
  • F16H57/0493—Gearings with spur or bevel gears
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H57/00—General details of gearing
  • F16H57/04—Features relating to lubrication or cooling or heating
  • F16H57/0402—Cleaning of lubricants, e.g. filters or magnets
  • F16H57/0404—Lubricant filters
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T74/00—Machine element or mechanism
  • Y10T74/19—Gearing
  • Y10T74/19991—Lubrication
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T74/00—Machine element or mechanism
  • Y10T74/21—Elements
  • Y10T74/2186—Gear casings
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T74/00—Machine element or mechanism
  • Y10T74/21—Elements
  • Y10T74/2186—Gear casings
  • Y10T74/2189—Cooling

Definitions

• the invention relates to a method for lubricating vehicle transmissions according to the preamble of patent claim 1 and a vehicle transmission according to the preamble of patent claim 5.
• Conventional gearboxes, transmission, distributor or axle transmissions usually consist of a cast housing, which contains bearings, transmission shafts, clutches and gear wheels. To lubricate the gears and bearings, an oil bath is usually provided, into which the gears are immersed and which they swirl around. This system is suitable for normal applications and vehicles.
• This transmission technology is no longer sufficient for large, modern special vehicles, in which increasingly higher engine outputs are required today.
• Very high engine outputs would require gearboxes with a considerably larger dimension, and in addition to the disadvantage of the significantly larger space requirement lead to a significant increase in weight. In particular, the increased space requirement is not acceptable, since the loading area would then have to be higher, which in turn would entail considerable disadvantages, such as unstable driving behavior.
• the conventional method of gear lubrication and the conventional construction method do not allow a reduction of the gear dimensions even when using modern materials that allow higher loads on the shafts, gears and bearings.
• the reason for this is that when the higher loads and pressures occur in the bearings and on the tooth flanks, there is a much higher heat development, since losses occur both on the bearings and on the gear transmissions.
• the power losses, which are all converted to heat are 10 to 15% for manual transmissions and 5 to 10% of engine power for transmission and axle transmissions.
• the undesirable heat output is approximately 50 to 80 kW.
• 80 liters of oil are soon heated to 150 ° C, reaching a critical point at which damage to the gearbox occurs.
• the vehicle must be stopped and, before continuing, cooled down with great expenditure of time and forms a traffic obstacle during this time.
• the cooling or lubricity is no longer sufficient, even if several gears are immersed in the lubricating oil.
• a higher filling of the gearbox housing with oil does not help, because the gears then circulate the oil too much, which leads to additional power losses and additional heat production, so that the gearbox would heat up even faster.
• the lubricating oil is injected directly into the intermeshing tooth flanks and into the bearings by means of specifically arranged nozzles, so that sufficient oil is supplied at the corresponding points. So that the gears do not dip into the oil and whirl it around like in a centrifuge, which would mean an additional high loss of power, the oil is preferably pressed out of the closed gear housing by means of compressed air. It is introduced into an oil tank that can be provided at any location. There it is defoamed and, if necessary, recooled in order to be used as normal, fresh oil by means of a pump and preferably via one provided in the pressure line Filters in turn to be fed to the nozzles.
• This lubrication system now makes it possible to transmit very high outputs without the need for gearboxes that take up a lot of space and have an excess weight of hundreds of kilos, which would inevitably reduce the payload of the vehicle.
• the new concept of a Qeltank located outside the gearbox allows a larger oil supply to be provided without the known space problems for the gearbox, thus increasing the durability of the gearbox and reducing the susceptibility to failure of the gearbox lubrication system.
• the vehicle transmission according to the invention contains a double-walled transmission housing, which enables use in connection with the lubrication method according to the invention and brings further advantages.
• Conventional gear boxes made of gray cast iron would only be able to withstand the high loads of the bearing and torsion pressures in a very heavy version.
• Very high bearing loads to be introduced into the gearbox walls arise due to the high torques required for off-road vehicles with large tires, especially on gradients or difficult terrain when driving with small gears.
• Thanks to the new construction of the gear housing made of thin, tempered sheets in a double-wall welded construction high rigidity is achieved with very low weight and, thanks to the small external dimensions, a small space requirement is achieved.
• the cavities between the walls of the gear housing are preferably filled with oil which is sprayed onto the points to be lubricated via nozzles on the inner wall of the housing.
• the cavity between the walls also serves as a Additional oil container, which is used in this oil to cool the gearbox and also has the advantage that the noise generated at high loads is damped.
• Fig. 1 shows a conventional transfer case, as it is used for example for all-wheel drive vehicles.
• Fig. 2 shows a horizontal four-shaft transmission when the vehicle is tilted to the right side.
• Fig. 3 shows a cross section of a manual transmission with two shafts, in which the gear housing is partially double-walled (side walls), partially single-walled for better illustration.
• FIG. 4 shows a longitudinal section through a manual transmission according to FIG. 3.
• Fig. 5 shows a horizontal three-shaft transmission according to the invention.
• Fig. 6 shows a control valve for controlling the oil level in the gearbox.
• FIG. 7 shows a further exemplary embodiment of the transmission according to the invention in cross section along a vertical plane.
• the process for lubricating vehicle transmissions brings great advantages especially in connection with heavy vehicles, special vehicles, such as trucks, heavy military vehicles, mobile cranes etc. and offers new possibilities, but is also suitable for normal applications in smaller commercial vehicles.
• the vehicle transmission according to the invention is described below primarily with reference to a manual transmission. However, it should be noted that the transmissions according to the invention are suitable for all types of transmissions which are used together with vehicles or similar machines.
• the method according to the invention for lubricating a vehicle gearbox does not use a so-called oil sump for lubricating the transmission, as has been known hitherto, but rather the lubricating oil is injected directly into the meshing tooth flanks and into the bearings by means of specifically arranged nozzles 43 (FIG. 5).
• the gearwheels are not immersed in an oil bath, so that the well-known energy loss effect that the oil is whirled around in a centrifuge does not occur.
• an excess pressure of 0.12-1 bar is preferably built up using compressed air inside the housing, depending on the level of the external oil tank and the line resistance, so that Oil is pressed out of the closed housing at one or more points. This measure should normally be necessary, since the oil tank is usually not placed directly below the gearbox and the oil can therefore not drain off independently. So that the non-metallic sealing rings on the housing are not overloaded, a control of the pressure is preferably provided. there compressed air is only admitted into the gearbox when a certain amount of oil has accumulated on the bottom of the gearbox housing. Valves are preferably used for regulation.
• a valve 35 for example a solenoid valve or a control valve controlled by pressure air, which is attached to the inside of the gearbox housing, opens as soon as the oil level exceeds a certain level and the excess oil is pressed out of the housing.
• the oil is introduced into an oil tank 40 provided at any location via discharge lines 37 (FIG. 5).
• discharge lines 37 FIG. 5
• the oil tank 40 is inserted at a location corresponding to the vehicle construction, where there is sufficient space can be built. This allows a larger oil supply to be provided and the oil to be processed outside of the transmission during operation.
• the oil Before the oil is fed back to the injection nozzles 43, it is defoamed and, if necessary, cooled.
• the oil is pumped from the oil tank to the nozzles by means of a pump.
• a filter is preferably installed in the oil line or in special devices, which filters out impurities, in particular the harmful metal abrasion of the gear elements, from the oil.
• the oil defoamed and cleaned in this way can be processed while the gearbox is in use and thus optimally perform the lubrication function. As the oil is continuously supplied to the transmission in a fresh state, the transmission life increases compared to conventional transmission lubrication.
• the lubrication system according to the invention makes it possible, due to the separate arrangement of the oil tank, the gentle lubrication of the transmission and the avoidance of energy losses due to an oil centrifuge effect, to transmit very high outputs without the need for transmissions which take up an excessive amount of space and have an intolerable weight .
• FIG. 1 shows a conventional transmission housing 1 with a so-called transfer case with three shafts 11, 12, 13. These three superimposed shafts are equipped with gears 14, 15, 16.
• Such transfer cases are used in particular for trucks, military vehicles, mobile cranes, tire loaders, articulated trucks, forestry vehicles, etc. Only the lowest gear 16 may be immersed in the oil bath 3. If one were to fill the gear housing 1 up to half with oil, which would actually be desirable in order to achieve sufficient lubrication of the top gear 14 and the shaft 11, a so-called oil centrifuge would result. at A high-speed gearbox would have over 50% loss of power that would be converted into heat.
• the conventional transfer case is still based on the principle shown with only a small immersion depth of a gear, whereby one has to accept that the gear is heated due to insufficient lubrication and accordingly a lot of wear occurs.
• the gearwheels wear out, the gearbox starts to "howl" when driving at high speed and must finally be replaced.
• Figure 2 shows a horizontal four-shaft transmission of conventional design. If the vehicle is inclined to the right side, the transmission housing 1 also comes into an inclined position and the oil accordingly flows to the right side. Apparently, the left-hand gears 21, 22 no longer dip into the oil bath 3 and are therefore practically no longer lubricated. This leads to damage in the shortest possible time and ultimately to the destruction of the gearbox. Such a lubrication method is obviously unsuitable for wide gears in which the shafts 25 are arranged in a horizontal plane.
• FIG. 3 now shows an embodiment of a standing manual transmission according to the invention in cross section.
• the gear housing 1 is essentially double-walled with an outer wall 9 and an inner wall 8.
• the double-walled design which is of a lightweight construction, brings a strong increase in stability and makes the housing 1 torsion-resistant.
• Conventional gear boxes made of gray cast iron would not be able to withstand similarly high loads with low deformations or would have to Practice intolerably large dimensions.
• the walls 8, 9 are preferably made of tempered steel or light metal sheets and are welded to connecting elements 31, 32 and together form the closed gear housing.
• the dashed line schematically indicates a gear cover 6, in which a switching device, not shown, can be integrated.
• the cavities 7 between the outer wall 9 and the inner wall 8 are filled with oil.
• Figure 4 shows the gear just described in a longitudinal section.
• the upright manual transmission is enclosed by a transmission housing 1, which is closed at the top with a gear cover 6.
• the front and rear of the transmission housing is formed by a double wall with an inner wall 4 and an outer wall 5.
• 5 bearing bushes 10 are welded in which shafts 20 are mounted and at the same time a stiffening cause this double wall 4, 5.
• Six gear gears 19 are shown schematically. Fresh oil is fed in from the oil tank by means of a constant pump through two supply openings 2. This is then injected directly into the engagement of the gears through several nozzles 7. These nozzles 7 are provided directly on and / or in the inner wall 4 or are integrated into this.
• the cavities between the different double walls 4, 5 and 8, 9 can form separate chambers or can be connected to one another so that the oil can circulate freely in these cavities.
• FIG. 5 shows a horizontal three-shaft transmission, for example a horizontal transfer case as used in all-wheel drive vehicles.
• the gear housing 1 is preferably welded from tempered sheet metal.
• the upper wall 28 is double-walled and thus also serves as an oil container for Cooling and soundproofing.
• the front and rear gear covers, which seal off the gear housing, with the shaft bearings integrated therein are not shown. They are preferably also made in a double wall construction.
• the lower wall 29 has two depressions 31, each of which contains a sensor 33. When the oil level rises in these depressions, these sensors 33 produce a change in the output potential, which serves to control a solenoid valve 35.
• the senor controls a compressed air solenoid valve, which allows compressed air to flow into the transmission via a nozzle, for example with a diameter of 0.4 to 0.5 mm.
• the increased internal gear pressure accelerates emptying.
• the compressed air solenoid valve is usually closed approx. 7 seconds after the sensor has been removed. Discussed here is the embodiment of the invention designed for very wide gears, where, when traveling at an incline, the compressed air supply opened by the lower-lying sensor would simply flow off via the "dry", opposite and higher-lying opening, thereby foaming only the oil.
• the solenoid valve 35 then opens and the accumulated oil flows back to the oil tank 40 via the oil line 37.
• a pneumatic valve 38 is actuated by means of this electrical pulse, which opens, whereupon the compressed air passed via a pressure reducing valve 34 reaches the interior of the transmission housing 1.
• a pressure vessel 38 serves as the source, the internal pressure of which is, for example, approximately 10 bar. This pressure can be reduced to approx. 0.1 to 1 bar by the pressure reducing valve 34 and the compressed air finally reaches the gear housing via a throttle body 39, where it serves to press out the accumulated oil.
• a small directly or indirectly driven oil pump 45 or a slightly jammed return feeds the oil to the gearbox via another oil line 49.
• a fine filter 47 is interposed between this oil line 49 and is used to clean the lubricating oil.
• the upper wall 28 of the gear housing 1 has a plurality of nozzles 43 (variable bores) on its inside, which inject the lubricating oil. In this way, a closed oil circuit is formed in which the used oil is defoamed, recooled, filtered and again metered to the transmission.
• a motor 41 with a fan is preferably provided, which is switched on when necessary and cools the oil tank 40.
• FIG. 6 shows a control valve for regulating the oil level in the transmission housing.
• the control valve 50 shown is optimally suited for this purpose and allows reliable control in the simplest way.
• This control valve 50 is not controlled by current like the magnetic valve 35 mentioned above (FIG. 5), but works with compressed air.
• a housing 51 there is a vertical axis 52 which is fixedly connected to a valve cone 53 located in the lower part of the housing 51.
• a piston in the upper housing area 54 firmly connected to this axis 52.
• the piston 54 contains on its periphery a sealing ring 59 which seals a chamber area 60.
• Figure 7 shows a further embodiment of a vehicle transmission in cross section.
• the gear housing 1 is only partially double-walled.
• a gear cover 6 lying on the top of the gear is indicated by dashed lines.
• 1 steel plate or sheet is welded in to reinforce the housing.
• the resulting cavities 65, 66 can in turn be used to hold lubricating oil, whereby only some of these cavities 65, 66 can be filled with oil.
• only the cavities 66 on the side walls are filled with oil.
• a suction device can also be provided.
• the oil can be drawn off permanently or also controlled by sensors at regular intervals and fed back to the injection nozzles via a closed circuit.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Details Of Gearings (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4206372

Family Applications (1)

Country Status (6)

Families Citing this family (34)

Family Cites Families (17)

• 1987
  • 1987-04-02 CH CH1266/87A patent/CH675758A5/de not_active IP Right Cessation
• 1988
  • 1988-03-22 BR BR888806478A patent/BR8806478A/pt unknown
  • 1988-03-22 WO PCT/CH1988/000063 patent/WO1988007641A1/de not_active Application Discontinuation
  • 1988-03-22 EP EP88902378A patent/EP0308441A1/de not_active Ceased
  • 1988-03-31 CA CA000563137A patent/CA1310278C/en not_active Expired - Lifetime
• 1991
  • 1991-05-15 US US07/701,643 patent/US5099715A/en not_active Expired - Fee Related

Non-Patent Citations (1)

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