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
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/34—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
• • 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
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/34—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
  • F01L1/344—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
  • F01L1/3442—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
• • 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
  • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
  • F15B1/02—Installations or systems with accumulators
  • F15B1/024—Installations or systems with accumulators used as a supplementary power source, e.g. to store energy in idle periods to balance pump load
• • 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
  • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
  • F15B15/08—Characterised by the construction of the motor unit
  • F15B15/12—Characterised by the construction of the motor unit of the oscillating-vane or curved-cylinder 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
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/34—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift
  • F01L1/344—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear
  • F01L1/3442—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of means for changing the timing of the valves without changing the duration of opening and without affecting the magnitude of the valve lift changing the angular relationship between crankshaft and camshaft, e.g. using helicoidal gear using hydraulic chambers with variable volume to transmit the rotating force
  • F01L2001/34423—Details relating to the hydraulic feeding circuit
  • F01L2001/34446—Fluid accumulators for the feeding circuit

Definitions

• the invention relates to a device for the variable adjustment of the timing of gas exchange valves of an internal combustion engine with a drive element, an output element, at least one pressure chamber, a pressure medium supply device and at least one pressure accumulator, by means of the pressure medium supply means of the at least one pressure chamber pressure medium supplied or can be removed from this, wherein a phase position of the output element relative to the drive element is variable by pressure medium supply to or pressure medium discharge from the pressure chamber, wherein the pressure accumulator has a displaceable element which is provided with a first pressure surface which partially defines a storage space, wherein the storage space is connected to the pressure medium supply device, wherein the displaceable element can be moved against the force of a force accumulator by pressurizing the storage space.
• the device usually comprises an adjusting device, which is driven by a crankshaft and transmits its torque to the camshaft.
• a hydraulic trained raulischer actuator which makes it possible to influence the phase angle between the crankshaft and camshaft targeted.
• a pressure medium supply device is provided to supply the adjusting device with pressure medium.
• Such a device is known, for example, from EP 1 025 343 B1.
• the device comprises two mutually rotatable rotors, wherein an outer rotor is in driving connection with the crankshaft and the inner rotor is rotatably connected to the camshaft.
• the device comprises a plurality of cavities, wherein each of the cavities is divided by means of a wing into two counteracting pressure chambers. By supplying pressure medium to or pressure fluid removal from the pressure chambers, the wings are moved within the pressure chambers, whereby a targeted rotation of the rotors to each other and thus the camshaft is caused to the crankshaft.
• the pressure fluid inlet to, or the pressure drain from the pressure chambers is controlled by a pressure medium supply device, the pump, a pressure medium, a tank, a control valve, and a plurality of pressure medium lines comprises.
• a pressure medium line connects the pressure medium pump with the control valve.
• a further pressure medium line connects one of the working ports of the control valve with the pressure chambers.
• the pressure medium is usually taken from the lubricant circuit of the internal combustion engine.
• the pressure in the pressure medium system in each Bethebsphase the internal combustion engine must exceed a certain value. This is critical especially in the idling phases of the internal combustion engine, since the pressure medium pump is driven by the crankshaft and thus the system pressure increases with the speed of the internal combustion engine.
• the system pressure provided by the pressure medium pump is further dependent on the pressure medium temperature, wherein the system pressure decreases with increasing temperature.
• the pressure medium pump must be designed such that under the most unfavorable conditions it provides sufficient system pressure to ensure a sufficiently rapid adjustment of the phase angle of the inner rotor to the outer rotor.
• the pressure medium pump In order to ensure the required adjustment speed even under the most unfavorable pressure conditions, such as high pressure medium temperatures and / or low speeds, the pressure medium pump must be designed accordingly. This means that pressure medium pumps are used, which are designed for the peak requirements of the adjusting device and thus are dimensioned too large during most operating phases of the internal combustion engine. Alternatively, controllable pressure medium pump can be used, which provide demand-pressure means available. In both cases, the increased effort has a negative effect on the costs, the space requirement and the fuel consumption of the internal combustion engine.
• a pressure accumulator is arranged between the pressure medium pump and the control valve, which communicates with the pressure medium supply device.
• This accumulator is filled in phases of high system pressure with pressure medium. If the system pressure drops, the accumulator automatically empties, whereby the Druckstoffersseinhchtung additional pressure medium is provided. Thus, the phase adjustment of the device is supported.
• a disadvantage of this embodiment is the fact that the pressure accumulator is emptied even if the system pressure is not due to an adjustment process, but due to other external circumstances, for example by a decrease in the speed drops. Thus, for a subsequent Phasenverstellvorgang lower pressure support and a lower pressure medium volume from the pressure accumulator available.
• a further disadvantage is that the maximum pressure with which the pressure accumulator can support the pressure medium supply device corresponds to the pressure which prevailed directly before the phase adjustment process in the pressure medium supply device. Is at high temperatures and low speeds of the engine control an adjustment to the Directed device, the pressure support of the pressure accumulator falls lower because the system pressure with which the pressure accumulator was filled, was low. This can result in that the adjustment process can not be carried out, or the adjustment speed is significantly reduced. Thus, an interpretation of the pressure medium pump on the peak load with the resulting disadvantages is also required in this case.
• the invention has for its object to provide a device for variable adjustment of the timing of gas exchange valves of an internal combustion engine, with a functionally reliable adjustment of the timing should be ensured at high adjustment speeds in each phase of operation of the internal combustion engine. It should also be possible to dispense with an oversizing of the pressure medium pump (design for the expected peak loads) as well as the use of variable pressure medium pumps.
• the displaceable element has at least a second pressure surface, which limits a control chamber partially, which can be displaced by pressurizing the control chamber, the movable element against the force of the energy storage and wherein within the pressure accumulator, a pressure medium flow from the storage room in the control room is prevented.
• the reservoir and the control chamber do not communicate with each other within the pressure accumulator.
• the displaceable element can for example be designed as a pressure piston, which can be displaced within a pressure vessel against the force of an energy accumulator designed as a spring element.
• energy storage can be used, for example, reversibly deformable body, for example made of elastomers, or gas-filled bubbles. Due to the design of the accumulator with a verlagerba ren element, which partially isolated spaces within the pressure accumulator, these two spaces can be controlled separately, ie filled and / or emptied, be. Apart from leakage there is no connection between the rooms. For example, different pressure sources for filling the storage space and the control room can be used.
• a pressure medium connection between the reservoir and the control chamber can be provided within the pressure accumulator. Pressure medium which is supplied to the control room, can get over this pressure medium connection in the storage room.
• a reverse flow of pressure medium is prevented by the storage space in the control room. This can be realized for example via a pressure medium channel in the pressure piston or the housing of the pressure accumulator, in which a check valve is arranged.
• the filling of the storage space and the control room can be done solely by the filling of the control room. If the accumulator is emptied, the control room is switched to tank. The storage room empties into the pressure medium supply device, the control chamber depressurized into the tank. A transfer of pressure medium from the reservoir into the control chamber is prevented by the check valve.
• the control chamber can support the filling of the reservoir space.
• the control chamber is also filled with pressure medium during the filling process of the storage space.
• a force acts on both pressure surfaces of the pressure piston, whereby a higher force is stored in the energy store (the spring element is compressed more strongly).
• the venting of the control chamber can be done faster than the emptying of the reservoir into the pressure medium supply device.
• the entire force that was stored in the energy storage acts on the first pressure surface on the pantry.
• the pressure at the beginning of the assist process can be reduced by up to a factor of
• a 1 corresponds to the surface area of the first pressure surface and A 2 corresponds to the surface area of the second pressure surface. Is used as
• Force memory for example, a spring element used, so the pressure increases
• the invention is based on the fact that in a device for variably setting the timing of gas exchange valves of an internal combustion engine with a drive element, an output element, at least one pressure chamber, a pressure medium supply device and at least one pressure accumulator, wherein by means of
• Pressure medium supply means of the at least one pressure chamber can be supplied with pressure medium or removed therefrom, wherein a phase position of the output element relative to the drive element is variable by pressure medium supply to or pressure medium discharge from the pressure chamber, a displaceable element of the pressure accumulator at least two independently formed and pressurizable spaces in Displacement direction of the element limited.
• at least one of the spaces storage space
• at least one additional space control space
• the control chamber supports the filling process in such a way that the displaceable element is deflected more strongly than would be the case without the center of pressure of the control chamber.
• the pressure accumulator By increasing the pressure provided by the pressure accumulator, the pressure accumulator can intercept peak consumption, so that the pressure medium pump can be designed for normal operation of the internal combustion engine. There are no oversized or regulated pressure medium pumps needed to ensure a reliable and fast adjustment of the phase position. In addition, the adjustment speed of the adjusting device is increased. Alternatively, the adjusting device can be dimensioned smaller at the same adjustment speed. What can reduce the mass, the moment of inertia and the costs.
• control chamber can be selectively connected to a pressure source or a tank during operation of the internal combustion engine.
• the pressure source can be, for example, the pressure medium supply device or its pressure medium pump or a separate source, for example the pressure source of a servo consumer (eg the power steering).
• the pressure accumulator can be completely filled even in operating phases with low system pressure.
• the selective connection to a pressure source or the tank is established via control means, for example a 3/2-way valve in the form of a switching valve (for example a seat valve) or a proportional valve (for example a slide valve).
• control means may be, for example, electromagnetically actuated hydraulic valves, such as directional control valves (for example switching or proportional valves), pilot operated check valves or the like.
• control means receive from an engine control unit of Internal combustion engine control signals according to which the accumulator is filled or emptied.
• control means can be provided that the hydraulic actuating device of the control means communicates with the pressure medium supply device.
• the control means will automatically be switched below a defined value. This reduces the regulatory burden considerably.
• control room without detour via a consumer, can be emptied into a tank.
• control chamber is preferably emptied against atmospheric pressure, usually via a proportional or switching valve.
• control means are provided, wherein the control chamber can be selectively connected by means of the control means with a tank or the pressure source.
• the control means may be formed, for example, as a directional control valve.
• control means are provided which lock in a first state a pressure medium flow from the reservoir to the pressure medium supply device and allow a pressure medium flow to the reservoir and the control chamber and in a further state, the pressure medium flow of the Allow storage space to the pressure medium supply device and connect between the control room and a tank, without detour via a consumer produce.
• the storage space and the control chamber are connected via a check valve, wherein the connection between the control means and the spaces is arranged and wherein the check valve blocks a pressure medium flow from the storage space to the control room.
• a supply line may be provided, which connects the pressure medium supply device to the storage space and be provided a control line which connects the control chamber with a pressure source.
• the control means may be formed as a single-way valve, each having a connection for the supply line, the control line, the control room, the storage room and the tank. As a result, the number of components and the control effort during operation of the internal combustion engine is reduced.
• the control means may comprise at least a first directional valve, which is arranged in the control line.
• the control means further comprise a second directional control valve, which is arranged in the supply line.
• the directional control valves can be designed, for example, as switching or proportional valves.
• the control means may further comprise a pilot operated check valve disposed in the supply line.
• a check valve may be provided, which blocks a pressure medium flow from the control chamber in the direction of the pressure source.
• the pressure medium volume located in the control chamber is trapped until it is connected to a tank.
• the displaceable element is held in the deflected position, even if the system pressure drops and thus prevents unwanted emptying of the storage space.
• a check valve is provided between the reservoir and the pressure medium supply device, which blocks a pressure medium flow from the pressure medium supply device in the direction of the storage space. This prevents that pressure peaks that are generated in the actuator are transmitted to the pressure accumulator.
• the pressure fluid flowing back out of the pressure chamber of the actuating device during a pressure peak is supported on the non-return valve, thereby increasing the hydraulic rigidity of the device and thus increasing the adjustment speed and improving torque transmission from the crankshaft to the camshaft.
• the pressure support of the pressure accumulator can thus be activated by simply switching one or more control means.
• the pressure medium volume is provided which is collected in the operating phase of the internal combustion engine in which the phase position is kept constant in the storage space.
• the pressure provided by the pressure accumulator corresponds either to the current system pressure multiplied by a factor which can amount to 1 + A 2 / Ai or to a maximum system pressure which exists during the filling phase multiplied by the same factor.
• the full factor 1 + A 2 / Ai is always present when the full storage capacity of the energy storage has not been exhausted, the spring element is not yet compressed to block or the pressure piston is still applied to the attacks.
• the displaceable element has a third pressure surface, which at least partially limits a counter-pressure space, wherein a pressure medium loading of the counter-pressure chamber displaces the displaceable element in the opposite direction, such as a pressurizing of the control chamber or the storage space.
• a pressure medium loading of the counter-pressure chamber displaces the displaceable element in the opposite direction, such as a pressurizing of the control chamber or the storage space.
• the pressure support of the pressure accumulator can be used with every phase adjustment process. For this purpose, always the control means (Directional valves and / or unlockable check valves) in the position in which the reservoir is emptied when a phase adjustment is requested. In the operating phases between the phase adjustment requirements, the pressure accumulator can fill up. Another possibility is to switch on the pressure support of the pressure accumulator as needed. If the engine control detects that the pressure or volume flow delivered by the pressure medium pump is insufficient for phase adjustment, it releases the pressure support through the pressure accumulator. This procedure extends the times in which the accumulator can be filled and thus the performance of the pressure accumulator during pressure support.
• the control means Directional valves and / or unlockable check valves
• the pressure support of the pressure accumulator only as a "boosf function for critical adjustment processes that require, for example, a high volume flow or a high adjustment speed. If the engine control system detects that such a critical adjustment procedure is to be initiated, it will release the pressure support by suitably setting the control means.
• control means in one piece with a control valve which controls the pressure medium flow to and from the pressure chambers of the adjusting device.
• the ratio between the minimum flow cross-section between the control chamber and the tank and the minimum flow cross-section between the reservoir and the actuator is greater than the ratio between the surface area of the second pressure surface and the surface area of the first pressure surface.
• the maximum volume of the storage space corresponds to at least twice the volume required for a phase adjustment from a maximum late position to a maximum advance position.
• the pressure accumulator can open, for example, in the pressure medium line between the pressure medium pump and the control valve.
• the pressure accumulator opens into one of the pressure medium lines, which connects one of the working ports of the control valve with a group of pressure chambers.
• a second pressure accumulator may be provided, which opens into the pressure medium line, which connects the other working port of the control valve with the other group of pressure chambers.
• FIG. 1 shows very schematically an internal combustion engine
• Figure 2a shows a longitudinal section through the adjusting device
• FIG. 2b shows a cross section through an adjusting device
• FIG. 3 shows a first embodiment of a device according to the invention
• Figure 4 - 12 further embodiments of a device according to the invention.
• FIG. 1 shows an internal combustion engine 1 is sketched, wherein a seated on a crankshaft 2 piston 3 is indicated in a cylinder 4.
• the crankshaft 2 is in the illustrated embodiment via a respective traction drive 5 with an intake camshaft 6 and exhaust camshaft 7 in combination, with a first and a second device 10 for a relative rotation between the crankshaft 2 and the camshafts 6, 7 can provide.
• the devices 10 each comprise a hydraulic actuating device 10a, b, c and a pressure medium supply device 37.
• Cams 8 of the camshafts 6, 7 actuate one or more inlet gas exchange valves 9a or one or more exhaust gas exchange valves 9b.
• FIG. 3 shows a first embodiment of a device 10 according to the invention, with adjusting devices 10a, b, c of a pressure medium supply device 37 and a pressure accumulator 43.
• FIGS. 2a and 2b show an adjusting device 10a, b, c in longitudinal section or in cross section.
• the adjusting device 10a, b, c has a drive element designed as an outer rotor 22 and an output element designed as an inner rotor 23.
• the outer rotor 22 has a housing 22a and two side covers 24, 25 disposed on the axial side surfaces of the housing 22a.
• the inner rotor 23 is designed in the form of an impeller and has a substantially cylindrically designed hub member 26, extend from the outer cylindrical surface in the illustrated embodiment, five wings 27 in the radial direction outwards.
• the vanes 27 are formed separately from the inner rotor 23 and arranged in vane grooves 28 formed on the hub member 26. The vanes 27 are acted upon radially outwardly by means of winged springs 27a, which are arranged between the groove bottoms of the vane grooves 28 and the vanes 27.
• a plurality of projections 30 extend radially inwardly.
• the projections 30 are formed integrally with the peripheral wall 29.
• the outer rotor 22 is mounted by means of radially inner circumferential walls of the projections 30 relative to the inner rotor 23 rotatably mounted on this.
• a sprocket 21 is arranged, by means of which, via a chain drive, not shown, torque can be transmitted from the crankshaft 2 to the outer rotor 22.
• a sprocket 21 is arranged on one of the axial side surfaces of the housing 22a and rotatably fixed thereto.
• an axial opening is provided in each projection 30, which is penetrated by a fastening element 32, for example a screw, which serves for the rotationally fixed fixing of the side covers 24, 25 on the housing 22a.
• a cavity 33 is formed between two respective projections 30 adjacent in the circumferential direction.
• Each of the cavities 33 is bounded circumferentially by opposing substantially radially extending boundary walls 34 of adjacent protrusions 30, axially from the side covers 24, 25, radially inwardly of the hub member 26 and radially outward of the peripheral wall 29.
• a wing 27 In each of the cavities 33 projects a wing 27, wherein the wings 27 are formed such that they rest against both the side covers 24, 25, and on the peripheral wall 29.
• Each wing 27 thus divides the respective cavity 33 into two counteracting pressure chambers 35, 36th
• the inner rotor 23 is rotatable in a defined Winkeibreich to the outer rotor 22.
• the angular range is limited in one direction of rotation of the inner rotor 23 in that the wings 27 come to rest on a respective boundary wall 34 (early stop 34a) of the cavities 33.
• the angular range in the other direction of rotation is limited by the fact that the wings 27 come to rest on the other boundary walls 34 of the cavities 33, which serve as a late stop 34b.
• the phase angle of the outer rotor 22 to the inner rotor 23 can be varied.
• the phase position of the two rotors 22, 23 are kept constant to each other.
• none of the pressure chambers 35, 36 during phases of constant phase position with Apply pressure medium usually the lubricating oil of the internal combustion engine 1 is used.
• a pressure medium supply device 37 For supplying pressure medium to or removing pressure medium from the pressure chambers 35, 36, a pressure medium supply device 37 is provided, which is shown in FIG.
• the pressure medium supply device 37 comprises a pressure source, which is designed as a pressure medium pump 38, a tank 39, a control valve 40 and a plurality of pressure medium lines 41.
• the control valve 40 has an inlet port P, a tank port T and two working ports A, B on.
• one of the pressure medium line 41 connects the pressure medium pump 38 with the Zuiaufan gleich P, the first working port A with the first pressure chamber 35, the second working port B with the second pressure chamber 36 and the tank port T to the tank 39.
• pressure medium from the pressure medium pump 38 via the pressure medium line 41 to the inlet port P of the control valve 40 pass.
• the inlet port P is connected to the first pressure chambers 35, while the second pressure chambers 36 are connected to the tank 39.
• a second position of the control valve 40 is provided that none of the pressure chambers 35, 36 communicates with the tank 39 and the inlet port P.
• the inlet port P is connected to the second pressure chambers 36, while the first pressure chambers 35 are connected to the tank 39.
• the check valve 42a prevents backflow of the pressure medium from the pressure chambers 35, 36 via the control valve 40 to the pressure medium pump 38.
• the pressure peaks are based on the check valve 42a, whereby an unwanted emptying of the pressure chambers 35, 36 is effectively prevented and thus the stiffness of the torque transmission and the adjustment speed is increased.
• the adjustment speed of the actuating devices 10a, b, c is dependent on the pressure provided or the pressure medium volume flow of the pressure medium pump 38 provided.
• the pressure provided or the pressure medium volume flow provided are in turn dependent on a multiplicity of factors, for example on the rotational speed of the internal combustion engine 1 and the pressure medium temperature.
• the pressure medium pump 38 In order to ensure the required adjustment speed even in the most unfavorable conditions, such as high pressure medium temperatures and or low speeds, the pressure medium pump 38 must be designed accordingly.
• pressure medium pumps 38 are used, which are designed for the peak requirements of the actuating device 10a, b, c and are thus dimensioned too large during most operating phases of the internal combustion engine 1.
• controllable pressure medium pumps 38 can be used which provide pressure medium as needed. In both cases, the increased expense has a negative effect on the cost and fuel consumption of the internal combustion engine 1.
• a pressure accumulator 43 is provided in the device 10 according to the invention.
• the pressure accumulator 43 comprises a displaceable element designed as a pressure piston 45, which can be displaced within a pressure vessel 44 against the force of an energy accumulator.
• the energy accumulator is designed as a spring element 46.
• other types of force gearing are also conceivable. such as suitably shaped elastomeric bodies or gas filled bladders.
• the pressure piston 45 has two pressure surfaces 47, 48. Together with the pressure vessel 44 limits the first pressure surface 47 a reservoir 49 and the second pressure surface 48 a control chamber 50. In this case, the pressure piston 45 and the pressure vessel 44 are formed such that within the pressure accumulator 43 is no connection between the two spaces 49 and 50. In the illustrated embodiment, the displacement path of the pressure piston 45 is limited by stops 54 for this purpose
• the storage space 49 is connected by means of a supply line 51 to the pressure medium supply device 37, wherein the supply line 51 downstream of the check valve 42a opens into this.
• the control chamber 50 can optionally be connected to a tank 39 or by means of a control line 52 to a pressure source or.
• a pressure source the pressure medium supply means 37.
• another pressure source such as the pressure medium pump 38 of a servo load, eg. The power steering, is used.
• the pressure fluid flowing out from the control chamber 50 is not directed into the tank 39 of the lubricating oil circuit of the internal combustion engine 1, but to the corresponding tank 39 of the servo consumer.
• a control means 60 in the form of a first directional valve 53 is provided.
• the first directional control valve 53 has a pressure port Pi, a control chamber port Ai and a discharge port Ti.
• the pressure port P 1 is connected to the pressure source, in the illustrated embodiment via the control line 52 to the pressure medium supply means 37.
• the control chamber connection A 1 is connected to the control chamber 50 and the drain port T 1 to the tank 39. In a first control position of the first directional control valve 53, the control chamber connection A 1 is connected to the pressure connection P 1 , while the outflow connection T 1 is connected to none of the other Ports P 1 , Ai communicates.
• a further check valve 42b may be provided, which is arranged in the control line 52 and prevents backflow of pressure medium from the control chamber 50 to the pressure medium supply device 37. If no adjustment request is directed to the device 10 during operation of the internal combustion engine 1 by the engine control, then the control valve 40 is in the second (middle) position and the first directional control valve 53 is in the first position. Consequently, no pressure fluid flows to or from the actuator 10a. At the same time pressure medium passes both via the supply line 51 into the reservoir 49 and via the control line 52 into the control chamber 50.
• a 1 corresponds to the surface area of the first pressure surface 47
• a 2 corresponds to the surface area of the second pressure surface 48
• p ma the maximum system pressure occurring during the filling phase
• D is the spring constant of the spring element 46. speaks. The maximum displacement is limited by the stops 54. Under the rest position is the state of the pressure piston 45 to understand, in which the spring element 46 is maximally relaxed. If a phase angle adjustment is requested by the engine control unit, the control valve 40 is transferred into its first or third position. Thus, pressure medium from the pressure medium pump 38 passes to the first and second pressure chambers 35, 36, whereby a phase adjustment by the actuator 10a, b, c is caused.
• the first directional control valve 53 is transferred into its second control position. In this control position, the control chamber 50 is connected to a tank 39. The under pressure in the control chamber 50 pressure medium is thus connected to atmospheric pressure, whereby a rapid draining of the control chamber 50 takes place. At the same time, the storage space 49 is emptied into the pressure medium supply device 37. Is this done?
• the check valve 42a is arranged in the pressure medium line 41 upstream of the supply line 51, it is ensured that the total pressure p and the entire volume of the reservoir 49 of the actuator 10a is available and not drained into the oil gallery of the internal combustion engine 1.
• the pressure medium supply device 37 can thus by adjusting the second control position on the first Directional valve 53 undergo pressure support.
• the adjustment speed of the adjusting device 10a can be increased significantly with the same dimensioning or the adjusting device 10a can be made smaller at the same adjustment speed without having to accept the disadvantages of an oversized or regulated pressure medium pump 38.
• a v corresponds to the minimum flow area between the reservoir 49 and the actuator 10a and the actuator 10a and the tank 39.
• one or more further control devices 10b, 10c can also be controlled by the pressure medium supply device 37 via further pressure medium lines 41 and further control valves 40.
• the further adjusting device 10 b can also benefit from the pressure accumulator 43.
• the branch leading to this adjusting device 10b lies downstream of the check valve 42a.
• the branch to the further actuator 10c in the flow direction in front of the check valve 42a is to be arranged.
• a vent 46a of the spring chamber to the tank 39 is provided.
• FIG. 10 Another embodiment of the device 10 according to the invention is shown in FIG.
• an additional check valve 42 c is arranged in the supply line 51.
• This check valve 42c prevents a flow of pressure medium from the pressure medium supply device 37 to the reservoir 49, which generated in the actuators 10a, b, c pressure peaks can not penetrate to the reservoir 49 of the accumulator 43, but supported on the check valve 42c.
• the hydraulic rigidity of the device 10 is increased analogous to the embodiment of Figure 5.
• a connecting line 55 is provided, which opens on the one hand between the pressure medium supply means 37 and the first directional control valve 53 in the control line 52 and on the other hand between the check valve 42c and the storage space 49 in the supply line 51.
• an additional check valve 42d may be arranged in the connection line 55, which prevents pressure medium from the storage space 49 between the pressure medium pump 38 and the check valve 42a from flowing into the pressure medium supply device 37.
• the check valve 42b and / or the entire pressure medium line 41, in which the check valve 42a is arranged, between the orifice points of the pressure accumulator 43 could be omitted.
• FIGS. 7 to 11 show further embodiments of a device 10 according to the invention.
• control means 60 are provided both in the control line 52 and in the supply line 51, which can block the flow of pressure medium at least in one direction.
• a single control valve in the form of a directional control valve 56 is provided.
• the directional control valve 56 has a pressure connection P 1 , a control chamber connection A 1 , a supply connection V 1 , a reservoir connection B 1 and a discharge connection T 1 .
• the pressure connection P 1 and the supply connection V 1 are connected to the pressure source, in the illustrated embodiment via the control line 52 or the supply line 51 to the pressure medium supply device 37.
• the control chamber connection A 1 is connected to the control chamber 50, the reservoir connection B 1 to the reservoir 49 and the drain port T 1 to the tank 39.
• a connecting line 55 is provided, which opens on the one hand between the directional control valve 56 and the control chamber 50 in the control line 52 and on the other hand between the directional control valve 56 and the reservoir 49 in the supply line 51.
• a check valve 42 d is arranged, which prevents a pressure medium flow from the supply line 51 to the control line 52.
• a first control position of the directional control valve 56 only the control chamber connection A 1 is connected to the pressure connection P 1 , while all other connections B 1 , T 1 , V 1 are closed.
• the supply connection V 1 communicates with the reservoir connection B 1 and the control chamber connection A 1 with the tank connection T 1 , while the pressure connection P 1 communicates with none of the other connections A 1 , B 1 , T 1 , V 1 , communicated.
• the directional control valve 56 is in the first control division. In this state, pressure medium from the pressure medium supply device 37 via the control line 52 and the directional control valve 56 can get into the control chamber 50. At the same time, the storage space 49 is also filled via the connecting line 55. In this state, the pressure accumulator 43 behaves similar to the pressure accumulator 43 shown in Figure 3. The pressure piston 45 is displaced against the force of the spring element 46 and the spaces 49, 50 with pressure medium filled. However, the pressure in the control chamber 50 also decreases. The reservoir 49, however, maintains the high pressure state since it is insulated on the one hand by the directional control valve 56 and on the other hand by the check valve 42d with respect to the pressure medium supply device 37. Thus, the pressure accumulator 43 maintains its filled state.
• FIG. 8 shows a further embodiment according to the invention, which differs from the previous embodiment only in the arrangement of the check valve 42a.
• the check valve 42a is arranged analogously to the embodiment from FIG.
• an embodiment analogous to FIG. 5 with two non-return valves 42a, one upstream and downstream of the supply line 51, respectively.
• FIGS. 9 to 11 show further devices 10 according to the invention which essentially resemble those of FIGS. 7 and 8.
• the devices 10 shown in FIGS. 9 to 11 are provided with two control means 60 instead of a single control means 60 (in the illustrated embodiment with a single way valve 56).
• the first control means 60 controls the communication between the pressure medium supply means 37 and the storage space 49
• the second control means 60 controls the communication between the pressure medium supply means 37, the control chamber 50 and the tank 39.
• the first control means 60 is designed as a pilot-operated check valve 42e, which allows a pressure medium flow from the pressure medium supply means 37 to the reservoir 49 in a first control position, but an opposite pressure medium flow in derogation. In the second control position, the pressure medium flows are permitted in both directions.
• the second control means 60 in this case is the first directional control valve 53 shown in the first embodiment.
• FIG. 10 shows an embodiment in which the pilot-operated check valve 42e is replaced by a second directional valve 57, in the specific embodiment a 2/2-way valve.
• the second directional control valve 57 In a first control position, the second directional control valve 57 does not allow any pressure medium flow between the pressure medium supply device 37 and the reservoir 49. In a second control position, the pressure medium can flow in both directions.
• FIG. 11 shows an embodiment in which the first directional control valve 53 has been modified such that in the first control position only one pressure medium valve is permitted by the pressure medium supply device 37 in the direction of the control chamber 50, whereas an opposite pressure medium flow is prevented in the first directional control valve 53.
• FIG. 12 shows a further aspect of the invention, which will be explained with reference to the embodiment shown in FIG. It is expressly pointed out that this aspect can be used in all previous embodiments.
• the device 10 differs from the device 10 shown in Figure 6 in that the connecting line 55 between the first directional control valve 53 and the control chamber 50 opens into the control line 52 and that no vent 46a of the spring chamber is provided.
• the spring chamber is rather equipped as a back pressure chamber 58, which can be filled with pressure medium.
• the first directional valve 53 is provided in this embodiment with an additional back pressure port G, which communicates with the back pressure chamber 58.
• the control chamber connection A 1 In a first control position of the first directional valve 53 is the Control chamber port A 1 connected to the pressure port P 1 , while the back pressure port G communicates with the drain port T 1 .
• the control chamber connection A 1 is connected to the outlet connection T 1 , while the pressure connection P 1 communicates with the counterpressure connection G.
• first directional control valve 53 If the first directional control valve 53 is in the first control position, there are no changes compared to the embodiment from FIG. In the second control position, however, additional pressure medium is conducted into the counterpressure space 58. This acts on a third pressure surface 59 of the pressure piston 45 with a force acting in the same direction as the spring element 46. As a result, the pressure in the reservoir 49 is additionally increased.
• the pressure accumulator 43 opens with the pressure medium line 41, which connects the pressure medium pump 38 with the control valve or valves 40.
• the pressure accumulator 43 opens into the pressure medium lines 41, which connects the control valve or valves 40 to the actuating devices 10a, b.
• the pressure accumulator 43 can also be used in other vehicle applications, for example in switchable cam followers or in applications in automated transmissions.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Valve Device For Special Equipments (AREA)
• Fuel-Injection Apparatus (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=40379613

Family Applications (1)

Country Status (7)

Cited By (1)

Families Citing this family (20)

Family Cites Families (19)

• 2007
  • 2007-11-24 DE DE102007056683A patent/DE102007056683A1/de not_active Withdrawn
• 2008
  • 2008-11-04 EP EP08851456A patent/EP2215331B1/fr not_active Not-in-force
  • 2008-11-04 US US12/744,093 patent/US20100313834A1/en not_active Abandoned
  • 2008-11-04 CN CN200880117533.0A patent/CN102625874B/zh not_active Expired - Fee Related
  • 2008-11-04 WO PCT/EP2008/064936 patent/WO2009065728A1/fr active Application Filing
  • 2008-11-04 AT AT08851456T patent/ATE514839T1/de active
  • 2008-11-04 KR KR1020107011078A patent/KR101468262B1/ko not_active IP Right Cessation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events