Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
  • F01L13/0005—Deactivating valves
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
  • F01L13/0015—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
  • F01L13/0015—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
  • F01L13/0063—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque by modification of cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
  • F01L13/0015—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
  • F01L13/0063—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque by modification of cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot
  • F01L2013/0068—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque by modification of cam contact point by displacing an intermediate lever or wedge-shaped intermediate element, e.g. Tourtelot with an oscillating cam acting on the valve of the "BMW-Valvetronic" type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L2305/00—Valve arrangements comprising rollers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L2800/00—Methods of operation using a variable valve timing mechanism
• • 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
  • Y10T74/2101—Cams
  • Y10T74/2107—Follower

Definitions

• the invention relates to a device for variable actuation of the gas exchange valves of internal combustion engines according to the preamble of claim 1.
• Such devices are used to design the control of gas exchange valves so that it becomes possible to operate reciprocating engines without the otherwise usual throttle valve.
• Such a device is known for example from DE 101 23 1 86 A1.
• a rotating cam first drives an intermediate link, which carries out an oscillating, pure rotary movement and carries a control cam, which is composed of a latching area and a stroke area.
• the control curve transfers the stroke curve required to actuate the valve to the role of a rocker arm-like output member, which in turn actuates the valve.
• the desired, different valve lift curves are generated in that the center of rotation of the intermediate member is shifted on an arc-shaped path which is concentric with the role of the driven member in its position when the valve is closed.
• the center of rotation is formed by a roller provided on the intermediate link, which is non-positively connected to an arc-shaped track in the housing supports, which is also concentric to the role of the output member, that is, an Aquidistante to the path of the turning center and which is referred to as the backdrop.
• the roller attached to the intermediate link is supported on a cam disc, the angular position of which determines the position of the center of rotation on its arc-shaped path.
• the object on which the present invention is based is to create a device which, with the saving of a separate adjusting device, is simple and with few components.
• the bolt on which the intermediate members are mounted is simultaneously designed as an adjusting shaft.
• the bolt on which the intermediate members are mounted is simultaneously designed as an adjusting shaft.
• it is provided with cams and can be freely rotated or stored in pendulum supports, in a four-bar linkage or in a slide.
• the cams are non-rotatably attached to the bolt.
• the cams are supported directly or indirectly in the housing. With direct support, in the housing Sliders for the cams are made of a material of increased strength.
• the desired valve lift curve is set by rotating the adjusting shaft with a suitable adjusting means, for example an adjusting motor.
• adjusting means for example an adjusting motor
• the bolt or the control shaft moves parallel to itself during the adjusting movement
• a connecting element must be arranged between the two, which permits this shift.
• this can be a cardan shaft, a Schmidt clutch, an Oldham clutch or a gear or chain gear.
• a lever mechanism is also suitable for hydraulic actuation.
• the device according to the invention can be provided including an adjusting motor or an adjusting device for all intake or exhaust valves of a cylinder head. If the intake and exhaust valves of a cylinder head are actuated by a common camshaft, the device according to the invention, including an adjustment motor or an adjustment device, can be provided for all intake and exhaust valves of a cylinder head.
• the device according to the invention, including an adjusting motor or an adjusting device can be provided separately for each valve of an engine, so that any combinations of valve strokes or opening angles of the individual valves of an engine are possible, including the deactivation of individual cylinders. As a rule, however, a common adjustment of several valves will be provided.
• one or more additional gear elements are arranged between the cam and the intermediate element.
• variable valve control ie also the device according to the invention, to keep the adjustment performance low and because this is higher in the loaded state of the device or its sliding joints and joints than in the non-energized state, which largely with the valve closed there is an adjustment according to the invention provided essentially during the common rest phases of all valves to be adjusted together. These are derived from the signal from the crankshaft and the camshaft and become shorter and shorter the more valves are adjusted together. Their number is therefore limited.
• the joint adjustment of the intake and exhaust valves of only one cylinder results in long, easy-to-adjust rest phases.
• it also enables individual load control of the individual cylinders with an adjustment strategy according to the invention such that the torques of the individual cylinders are regulated for each load state of the overall engine. This is particularly important in the lower load range for quiet engine operation, since the valve lifts do not normally correspond sufficiently due to tolerances.
• the signals required for this adjustment strategy are also supplied by the crankshaft angle encoder and assigned to the individual cylinders by the camshaft angle encoder.
• the solution according to the invention achieves the advantage of creating a secure adjusting device for gas exchange valves with simple components. In addition, a sensitive adjustment is advantageously achieved.
• Fig. 2 shows a cross section using the parts shown in Fig.1 with a pendulum support and adjusting shaft
• Fig. 3 is a perspective view of the device according to the invention with a pendulum support and the bolt as an adjusting shaft
• Fig. 4 schematically shows the interaction of engine management, accelerator pedal, angle encoder, adjusting motors and battery.
• Fig. 1 shows a camshaft 1 which carries a cam 2. This moves the roller 3 in the end region of the intermediate member 4.
• the roller 3 is rotatably attached to the intermediate member 4, which has a one-piece base body.
• the intermediate member 4 has a control cam 5, which is composed of a locking area 5a and a lifting area 5b.
• the intermediate member 4 is mounted on a bolt 6, the axis 7 of which is guided on an arc-shaped adjusting curve 8.
• the center of the arc-shaped adjustment curve 8 lies on the axis 9 of the roller 1 0 of the output member 1 1, which is supported via a joint 1 2 in the housing, not shown, and actuates the valve 1 3. It is clearly evident that an adjustment of the axis 7 on the adjustment curve 8 in the direction of the arrow 14 results in a reduction in the opening angle and stroke of the valve 1 3.
• Fig. 2 shows an embodiment in which the bolt 6 or its axis 7 is guided in a form-fitting manner on the circular-shaped adjustment curve 8 by a pendulum support 15.
• the cylinder head-side joint 1 6 of the pendulum support 1 5 or its axis coincides with the axis 9 of the roller 1 0 of the output member 1 1.
• the adjusting shaft 1 7 carries cams 1 8, which determine the position of the bolt 6 or its axis 7 on the adjusting curve 8 via tappet 1 8a.
• An adjustment of the axis 7 on the adjustment curve 8, as shown by the direction arrow 14, is caused by a rotation of the cam disk S or the adjustment shaft 17 according to the direction arrow 14a.
• the adjustment movement described results in a reduction in the stroke and opening angle of the valve 13. If the constructive If conditions allow (e.g. installation space), the plunger 18a can also be dispensed with and the cam disks 18 can act directly on the bolt 6.
• Fig. 3 shows a perspective view of the device according to the invention with pendulum support 15 for intake valve 19 and exhaust valve 20 of a cylinder, picked out from a series of cylinders or valves.
• the cylinder head-side joint 16 of the pendulum support 15 can be clearly seen, the axis of which coincides with the axis 9 of the rollers 10 of the output members 11, so that the bolt 6 is positively guided on an arc-shaped adjustment curve.
• the bolt 6 here simultaneously takes on the function of the adjusting shaft. It carries the cams 18 which are supported on hardened sliders 21 mounted in the housing and is rotatable in the pendulum support.
• the bolt 6 is connected to the adjusting motor 23 fixed to the housing via a suitable connecting element.
• an articulated shaft 22 serves as a connecting element.
• This embodiment offers considerable advantages with regard to the variety of parts, but also space in the area of the actual valve control. Since other connecting elements, such as Schmitt couplings, Oldham couplings, toothed and chain drives, are also possible in addition to cardan shafts, there is a certain flexibility for accommodating the adjusting motor 23.
• FIG. 4 schematically shows the interaction of accelerator pedal 40, adjusting motors 23, angle of rotation sensor 42 on the flywheel and angle of rotation sensor 43 on the camshaft with engine management 44.
• a signal emanating from accelerator pedal 40 or a sensor for its position is converted into a signal by engine management 44 the adjusting motors 23 are converted to increase or decrease the valve strokes.
• the engine management 44 evaluates the signals of the high-resolution rotation angle sensor 42 on the flywheel. These will assigned to the individual cylinders with the aid of the low-resolution angle of rotation sensor 43 on the camshaft or on another shaft running at half the crankshaft speed.
• signals are sent to the individual adjusting motors 23 for leveling the torque peaks or the crankshaft speed by correcting the valve strokes of the cylinders with smaller torques upwards and those of the cylinders with larger torques downwards.
• adjustment takes place, with or without compensation, during the common rest phases of the valves operated by an adjusting motor.
• the engine management 44 also takes their phase position from the sensor 43 on the camshaft.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Valve Device For Special Equipments (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=32103487

Family Applications (1)

Country Status (12)

Families Citing this family (14)

Family Cites Families (21)

• 2003
  • 2003-03-24 DE DE10312961A patent/DE10312961C5/de not_active Expired - Fee Related
• 2004
  • 2004-03-17 BR BRPI0408638-4A patent/BRPI0408638A/pt not_active IP Right Cessation
  • 2004-03-17 JP JP2006504707A patent/JP2006521492A/ja active Pending
  • 2004-03-17 ES ES04721164T patent/ES2334791T3/es not_active Expired - Lifetime
  • 2004-03-17 KR KR1020057014212A patent/KR101098170B1/ko active IP Right Grant
  • 2004-03-17 MX MXPA05009833A patent/MXPA05009833A/es active IP Right Grant
  • 2004-03-17 WO PCT/EP2004/002741 patent/WO2004085803A1/fr active Application Filing
  • 2004-03-17 CA CA002519578A patent/CA2519578A1/fr not_active Abandoned
  • 2004-03-17 CN CNB2004800078585A patent/CN100472035C/zh not_active Expired - Fee Related
  • 2004-03-17 AT AT04721164T patent/ATE449902T1/de not_active IP Right Cessation
  • 2004-03-17 US US10/551,541 patent/US7493878B2/en active Active
  • 2004-03-17 EP EP04721164A patent/EP1608850B1/fr not_active Expired - Lifetime
  • 2004-03-17 DE DE502004010416T patent/DE502004010416D1/de not_active Expired - Lifetime

Non-Patent Citations (1)

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