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
  • F01L1/02—Valve drive
  • F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
  • F01L1/047—Camshafts
• • 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
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/10—Valve-gear or valve arrangements actuated non-mechanically by fluid means, e.g. hydraulic
• • 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
  • F01L1/02—Valve drive
  • F01L1/024—Belt drive
• • 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
  • F01L1/02—Valve drive
  • F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
  • F01L1/047—Camshafts
  • F01L2001/0471—Assembled camshafts
  • F01L2001/0473—Composite camshafts, e.g. with cams or cam sleeve being able to move relative to the inner camshaft or a cam adjusting rod
• • 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
  • F01L1/02—Valve drive
  • F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
  • F01L1/047—Camshafts
  • F01L1/053—Camshafts overhead type
  • F01L2001/0535—Single overhead camshafts [SOHC]
• • 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
  • F01L9/00—Valve-gear or valve arrangements actuated non-mechanically
  • F01L9/20—Valve-gear or valve arrangements actuated non-mechanically by electric means
  • F01L9/21—Valve-gear or valve arrangements actuated non-mechanically by electric means actuated by solenoids
  • F01L2009/2125—Shaft and armature construction
  • F01L2009/2126—Arrangements for amplifying the armature stroke
• • 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
  • F01L13/0036—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 the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction
  • F01L2013/0052—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 the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction with cams provided on an axially slidable sleeve
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
  • F02M59/02—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type
  • F02M59/04—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by special arrangement of cylinders with respect to piston-driving shaft, e.g. arranged parallel to that shaft or swash-plate type pumps
  • F02M59/06—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by special arrangement of cylinders with respect to piston-driving shaft, e.g. arranged parallel to that shaft or swash-plate type pumps with cylinders arranged radially to driving shaft, e.g. in V or star arrangement

Definitions

• the present invention relates to a hydraulic actuator allowing the control of the lifting, the advance to the opening and / or the delay to the closing of the valves of the piston engines.
• the point of opening of the valves of the piston engines as a function of the angle of rotation of the crankshaft is defined by the angular phasing of the camshaft (s) relative to said crankshaft.
• the opening time and valve lift are defined by the cam profile.
• Admission Closing Delay control authorizes the adjustment of the charge introduced into the cylinder by “flow-tank”, in other words, by return in the intake manifold of the fresh gases admitted in excess.
• the back-flow obtained by controlling the Admission Closing Delay makes it possible to control the effective compression stroke, which makes it possible to provide a higher volumetric ratio offering better efficiency at partial loads and allows better control of knocking and performance at all speeds.
• the lift control limits the depth of valve lift in the piston (imprints having the shape of the valves on the piston) by allowing less lift of the valves at partial loads when the volumetric ratio is high.
• Electromagnetic actuators with solenoids currently have the best level of configuration, but notable faults make it difficult to industrialize them, including energy overconsumption, the panic of valves at high speeds, the lack of progressiveness when refitting the valves on their seats, the overheating of their electrical components, or the need to provide a higher electrical supply voltage than that ordinarily produced on the vehicle. In addition, their manufacturing cost is high and their reliability is difficult to ensure over the entire life of a vehicle. Electro-hydraulic devices have also been developed, such as that particularly intended for motors with low rotation speed built by "Sturman" in the United States in collaboration with "Siemens".
• the device according to the invention allows, according to a particular embodiment:
• the device according to the invention allows the implementation of most of the strategies for improving the power, the efficiency and the control of the emissions by controlling the opening advance, opening time and lifting. valves.
• the device according to the invention has a level of reliability and a production cost compatible with the requirements of the automotive industry.
• the cylinder head is simplified in particular by eliminating the line of camshaft usually embodied by bearings and their lubrication device, and by eliminating the bores of valve lifters.
• the vertical size of the engine can be reduced by eliminating the camshaft.
• hydraulic valve actuator for piston engines comprises:
• the hydraulic valve actuator for piston engines according to the present invention comprises:
• the device incorporating a set of valves and valves has the function of:
• the device according to the invention comprises:
• a device for measuring the angle of the crankshaft which, combined with a device for measuring the valve lift, informs the computer (s) about the opening point, the lift height and the point of effective closing of the engine valve (s). All of said measuring devices and said computers producing a control loop ensuring the movement of the engine valve (s) with sufficient precision.
• Figure 1 illustrates the block diagram of the hydraulic actuator according to the present invention in a four-valve configuration (for example for actuating the four intake valves of a four-cylinder engine).
• Figure 2 is a schematic representation of a circuit whose operation is identical to the previous one, but which is intended, for example, to actuate the eight intake valves of a four-cylinder engine with two intake valves per cylinder.
• Figure 3 is a schematic representation of a circuit whose operation is identical to the previous one, but which operates at higher pressure thanks to an additional pump, and this, in order to limit the consequences of the compressibility of the hydraulic fluid and the inertia of the valves on the operating precision of the device according to the present invention.
• Figure 4 is a perspective view showing the hydraulic actuator according to the present invention.
• FIGS. 5 to 7 are views illustrating in detail the valves of an engine controlled by the hydraulic actuator according to the present invention.
• Figure 8 is a sectional view showing the inputs and outputs of the hydraulic pump of the hydraulic actuator according to the present invention.
• Figures 9 and 10 are sectional views showing the possible positioning of the hydraulic actuator according to the present invention on an engine.
• Figures 11 to 13 are views illustrating the pump outlet shutters of the hydraulic actuator according to the present invention.
• Figure 14 is a sectional view showing the valve opening selector of the hydraulic actuator according to the present invention.
• Figures 15 to 21 are views showing the assembly of the various elements constituting the hydraulic actuator according to the present invention.
• Figure 22 is a schematic representation of a circuit whose operation is identical to the previous one shown in Figure 1 to 3, but the pump outlet shutter and the valve opening selector are combined in a single combined distributor.
• a hydraulic actuator 1 comprising at least one hydraulic cylinder 3 which is connected to a high pressure hydraulic circuit 10 by a conduit to ensure the opening of at least one valve 2 d '' a piston engine 12.
• the hydraulic actuator 1 comprises at least one volumetric hydraulic pump 4 comprising at least one outlet 6 and at least one inlet 7 and the speed of rotation of which is proportional to that of the crankshaft 5 of the engine 12.
• the hydraulic actuator 1 comprises at least one pump outlet shutter 8 which makes it possible to prevent the hydraulic fluid expelled at the outlet 6 from the volumetric hydraulic pump 4 from opening into a low pressure circuit 9 or into a reservoir 58, and from force it to go towards a high pressure circuit 10 communicating with one or more hydraulic actuator (s) 3 ensuring the opening of one or more valve (s) 2 of the engine 12.
• the hydraulic actuator 1 comprises at least one valve opening selector 11 which makes it possible to direct, via the high pressure circuit 10 the hydraulic fluid expelled at the outlet 6 from the volumetric hydraulic pump 4, towards the hydraulic cylinder 3 at least a valve 2 to allow its opening, while preventing said hydraulic fluid from being directed to one or more other valve (s) 2 which must remain closed.
• the hydraulic actuator 1 comprises at least one opening check valve 24 placed on the high pressure circuit 10 between the pump outlet 6 and the hydraulic cylinder 3 of at least one valve 2 which makes it possible to retain the fluid hydraulic in said hydraulic cylinder 3 of said valve 2 in order to keep it open.
• the hydraulic actuator 1 comprises at least one valve closing selector 25 which makes it possible to direct the hydraulic fluid contained in the hydraulic cylinder 3 from at least one valve 2 kept open by the opening non-return valve 24 towards the inlet or the inputs 7 of the volumetric hydraulic pump 4 in order to ensure the closing of the said valve (s) 2, and to prevent the hydraulic fluid contained in their hydraulic cylinder 3 from being introduced into the hydraulic cylinder 3 of a other or other valve (s) 2 which must remain in the closed position.
• the hydraulic actuator 1 comprises at least one non-return valve at the pump inlet 26 which allows the hydraulic fluid of the low pressure circuit 9 or of the reservoir 58 to be admitted to the inlet (s) 7 of the volumetric hydraulic pump 4 when the pressure of said low pressure circuit 9 or of said reservoir 58 is greater than that of said one or said inlet (s) 7 of the volumetric hydraulic pump 4 (FIG. 8).
• At least one of the valves 2 is provided with a measuring device emitting an electrical or electromagnetic signal which informs a computer of the lift height of the valve at a given instant.
• the low pressure circuit 9 is connected to the pressure lubrication circuit 15 of the engine 12.
• the low pressure circuit 9 can also be provided independent of the pressure lubrication circuit 15 of the engine 12.
• the low pressure circuit 9 is independent of the pressure lubrication circuit 15 of the motor 12, this can be maintained at a pressure higher than atmospheric pressure by means of an additional pump 13.
• the low pressure circuit 9 can then include a pressure accumulator 14.
• the pump outlet shutter 8 and the valve opening selector 11 can be combined into a single combined distributor 81 comprising at least one inlet connected to the outlet 6 of the volumetric hydraulic pump 4, which can be linked either with an output connected to the low pressure circuit 9, or with an output connected to at least one hydraulic cylinder 3 (FIG. 22).
• FIGS. 4 to 7 the hydraulic actuator of valves for piston engines has been shown, the cylinder and the chamber 20 of the hydraulic cylinder 3 ensuring the opening of the valve (s) 2 are arranged in a valve guide. 16, said cylinder and said chamber 20 cooperating with a cylinder piston constituted by a shoulder 19 arranged on the valve stem 18 to open the valve 2.
• the cylinder piston consisting of a shoulder 19 arranged on the valve stem 18 participates in guiding the valve 2 in the valve guide 16.
• the jack piston consisting of the shoulder 19 on the valve stem 18 has at least one seal 17.
• the valve guide 16 comprises at least one drain 22 near the intake or exhaust duct 21 that the cylinder head of the engine 12 includes to limit the passage of the hydraulic fluid to said intake or exhaust duct 21 (FIG. 5).
• the hydraulic cylinder 3 ensuring the opening of the valve (s) 2 includes an end-of-stroke damping device making it possible to brake the valve (s) 2 before they come into contact with their seat.
• the hydraulic cylinder 3 arranged in the valve guide 16 comprises an end-of-stroke damping device which consists of a small shoulder 23, arranged on the valve stem 18.
• the shoulder 23 cooperates with a portion of cylinder of small height and of diameter substantially greater than said shoulder 23 arranged in the upper part of the valve guide 16 for shearing the hydraulic fluid when the valve 2 reaches the end of the closing stroke which has the effect of reducing the speed of said valve 2.
• the hydraulic cylinder 3 ensuring the opening of at least one valve 2 comprises a purge device at its chamber 20 which consists of a shutter which can be opened by means of a control in order to allow the hydraulic fluid contained in said chamber 20 to escape to a low pressure circuit.
• the volumetric hydraulic pump 4 has been shown, the latter can be a vane pump whose stator has an internal profile which defines at least one independent inlet and outlet.
• a first variant consists in that the positive displacement hydraulic pump 4 can be a gear pump comprising at least two pinions and at least one independent inlet and outlet.
• a second variant consists in that the volumetric hydraulic pump 4 can be a variable displacement pump which makes it possible to vary the lifting speed of the valve (s) 2 of the engine 12 at a given speed of said engine.
• FIGS. 11 to 13 an exemplary embodiment of the pump outlet shutter 8 is illustrated.
• the pump outlet shutter 8 is a solenoid valve controlled by a computer.
• the seal between the pump outlet orifice (s) 29 and the protrusions 28 of the shutter rotor 27 is reinforced by a device 30 for keeping in contact 30 said or said outlet outlet (s). pump 29 with said protuberances 28 when these are positioned opposite said one or more pump outlet orifices 29.
• the contact holding device 30 consists of a shutter piston 31 positioned radially in the shutter housing 65 and which includes a pump outlet orifice 29 which passes through it longitudinally right through.
• the pump outlet orifice 29 is connected to a pump outlet conduit 32 by a radial orifice 33.
• the shutter piston 31 has a concave cylindrical bearing face with a radius substantially identical to that of the protrusions
• the shutter piston 31 has on the side of the shutter casing 65 a surface subjected to the pressure of the hydraulic fluid greater than the contact surface which it presents with the protrusions 28, so that it is kept in contact with said protrusions when the pressure of the fluid increases in the pump outlet duct 32 when said protrusions 28 pass (FIG. 13).
• the shutter piston 31 comprises at least one seal ensuring the seal between said shutter piston and the bore in which it is housed.
• the phase shift device of the shutter rotor 27 consists of at least one helical groove arranged inside said rotor cooperating with at least one helical groove arranged outside the shaft of driving said shutter rotor.
• the phase shift is effected by translation of the shutter rotor 27 parallel to its axis of rotation by means of a fork.
• the shutter rotor 27 has protuberances which are of sufficient width to close off the pump outlet orifice (s) housed in the shutter casing 65 whatever their longitudinal position relative to these latter.
• the protrusions 28 are provided for wide and of variable section over the length of the shutter rotor 27, so that they have a shutter time which varies according to the longitudinal position of the shutter rotor 27 relative to the pump outlet orifice (s) 29 which makes it possible to increase or decrease the lift stroke of the valve (s) 2.
• Control of the longitudinal position of the shutter rotor 27 relative to said pump outlet port (s) 29 is effected by means of a valve lift fork 62 which allows printing to said shutter rotor 27 a translation parallel to its axis of rotation
• the shutter rotor 27 comprises at least one inner straight groove 34 cooperating with at least one outer straight groove 76 provided on an opening sleeve 37 or any other drive element.
• the angular phase shift device of the shutter rotor 27 consists of the opening sleeve 37 comprising at least one internal helical groove 75 cooperating with at least one external helical groove 60 which comprises its drive shaft 59 or any other means of training.
• the opening sheath 37 also comprises at least one outer straight groove 76 cooperating with at least one inner straight groove 34 provided on the shutter rotor 27.
• the opening sleeve 37 can be operated in translation parallel to its axis of rotation by a valve opening advance fork 61 so as to to advance or delay the opening of the valve (s) 2 by angular phase shift of the shutter rotor 27 which it drives in rotation.
• valve lifting fork 62 acts on the longitudinal position of the shutter rotor 27 relative to the pump outlet orifice (s) 29 .
• the shutter rotor 27 may include at least one inner straight groove cooperating with at least one outer straight groove provided on its drive shaft or any other drive element.
• valve opening selector 11 which can be a rotary mechanical device contained in a casing and rotating at a speed proportional to that of the crankshaft 5 of the engine 12.
• valve opening selector 11 may consist of one or more solenoid valve (s) controlled by a computer.
• valve opening selector 11 is a rotary mechanical device contained in a selector housing 66, rotating at a speed proportional to that of the crankshaft 5 of the engine 12, and comprising a rotor opening selector 38 provided with a cam 39 which actuates one or more valve opening distributors 40 arranged radially in the selector housing 66.
• the opening selector rotor 38 is provided with an angular opening phase shift device relative to the crankshaft 5 of the engine 12 so that the valve opening selector 11 can be synchronized with the pump outlet shutter 8 and can select the valve (s) 2 at the desired time.
• the opening selector rotor 38 has a cam 39 which is integral with the opening sleeve 37, allowing the valve opening selector 11 to remain synchronized with the opening of the valve (s) 2 which depends the angular phase shift of the shutter rotor 27 relative to the crankshaft 5 of the engine 12.
• valve opening advance fork 61 allows the opening selector rotor to be dephased simultaneously and in the same proportions
• the angular phase shift device of the aperture selector rotor 38 consists of at least one helical groove 77 arranged inside said aperture selector rotor 38 cooperating with at least one helical groove 60 arranged outside of the drive shaft 59 of said aperture selector rotor 38 or of any other drive means.
• phase shift takes place by means of a fork by translation of said opening selector rotor 38 parallel to its axis of rotation.
• the cam 39 is provided with sufficient width to actuate the valve opening distributors 40 whatever its longitudinal position relative to said distributors.
• the valve opening distributor or distributors 40 consist of a cylindrical part 78 provided with one or more grooves 41 and taking place in a bore arranged in the selector housing 66.
• the groove (s) 41 are brought by axial translation of the cylindrical part 78 printed by the cam 39 at the level of conduits 42 arranged in the selector housing 66 in order to allow the circulation of the hydraulic fluid in said conduits.
• the cylindrical parts 78 are kept at the desired distance from the aperture selector rotor 38 by the combined action of a shoulder 44 arranged on said cylindrical parts 78 and bearing on the housing.
• selectors 66, and a spring 43 kept compressed by a plug 45 screwed into said casing.
• the plug 45 screwed into the selector housing 66 defines a chamber 46 which contains the spring 43 and which is connected to the low pressure circuit 9 or to the reservoir 58 by a conduit not shown.
• valve closing selector 25 which consists of a rotary mechanical device contained in a selector housing 66 and rotating at a speed proportional to that of the crankshaft 5 of the motor 12.
• valve closing selector 25 may consist of one or more solenoid valve (s) controlled by a computer.
• the valve closing selector 25 comprises a closing selector rotor 47 provided with a cam 48 which actuates one or more valve closing distributor (s) 49 arranged radially in the selector housing 66.
• the closing selector rotor 47 is provided with an angular phase shift device relative to the crankshaft 5 of the engine 12 so that the closing of the valve (s) 2 can be advanced or delayed.
• the phase shift device of the closure selector rotor 47 consists of at least one helical groove 79 arranged inside the closure selector rotor 47 cooperating with at least one helical groove 60 arranged outside the shaft drive 59 or any other drive means for said closing selector rotor 47.
• the phase shift takes place by translation of the closing selector rotor 47 parallel to its axis of rotation by means of a valve closing delay fork 63.
• the cam 48 is of sufficient width to actuate the valve closing distributors 49 regardless of its longitudinal position relative to the latter.
• the valve closing distributor (s) 49 consist of a cylindrical part 80 provided with one or more grooves 50 and taking place in a bore arranged in the selector housing 66.
• the groove (s) 50 are brought by axial translation of the cylindrical part 80 printed by the cam 38 at the level of conduits arranged in the selector casing 66 in order to allow the circulation of the hydraulic fluid in said conduits.
• the cylindrical parts 80 are kept at the desired distance from the closing selector rotor 47 by the combined action of a shoulder 51 arranged on said cylindrical parts 80 and bearing on the selector housing. 66, and a spring 52 kept compressed by a plug 53 screwed into said casing.
• the plug 53 screwed into the selector housing 66 defines a chamber 73 which contains the spring 52 and which is connected to the low pressure circuit 9 or to the reservoir 58 by a conduit not shown.
• the high pressure circuit 10 includes at least one closing check valve 54 upstream or downstream of the valve closing selector 25 in order to prevent the hydraulic fluid contained in the hydraulic cylinder 3 from one or more valve (s) ) 2 in the closing phase can not be introduced into the hydraulic cylinder 3 of another or other valve (s) 2 must remain closed (s).
• the closing non-return valve 54 positioned upstream or downstream of the valve closing selector 25, consists of a ball held on its seat by a spring.
• the pump inlet check valve 26 consists of a ball held on its seat by a spring.
• FIGS 20 and 21 there is illustrated a common casing consisting of one or more parts in which are contained together or in groups the components that are the positive displacement hydraulic pump 4, the pump outlet shutter 8, the selector opening of valves 11, the check valve (s) 24, the valve closing selector 25 and the closing non-return valve (s) 54.
• the positive displacement hydraulic pump 4, the shutter rotor 27, the selector rotor 38, and the closing selector rotor 47, or any combination of these four devices are rotated by a common shaft 59 itself driven by rotation by the crankshaft 5 of the engine 12 by means of a transmission device (FIGS. 15 to 19).
• the transmission device driving the common shaft 59 consists of a pulley 74 rotated by the crankshaft 5 of the engine 12 by means of a toothed belt or a chain, or a gear system consisting of '' at least one pinion.
• the common shaft 59 is provided with at least one helical groove 60 which rotates the shutter rotor 27, the opening selector rotor 38, the opening sleeve 37 and the closing selector rotor 47 or any combination of these three devices and cooperates with the internal helical grooves of some of these devices to allow their angular phase shift relative to the crankshaft 5 of the engine 12.
• the common casing consists of four main casings which contain the common shaft 59 and which are assembled end to end with respectively: *> a pump casing 64 comprising the volumetric hydraulic pump 4 and the non-return valve (s) pump inlet 26,
• the shutter casing 65 is traversed by conduits connecting the outlet (s) 6 of the positive displacement hydraulic pump 4 with the outlet outlet shutter (s) 8 on the one hand and with an opening manifold 68 consisting of a network of conduits arranged at the joint plane between the shutter casing 65 and the selector casing 66 on the other hand.
• the shutter casing 65 is traversed by conduits connecting the inlet (s) 7 of the volumetric hydraulic pump 4 with a closing manifold 69 consisting of a network of conduits arranged at the joint plane between the selector casing 66 and the closing collector housing 67.
• the selector housing 66 is traversed longitudinally by conduits 42 which connect the opening manifold 68 and the closing manifold 69 and which can be closed or opened by the valve opening distributor (s) 40 and by the or valve closure distributors 49.
• the conduits 42 comprise valve starting conduits 70 located between the valve opening distributor (s) 40 and the valve closing distributor (s) 49 which are connected to the hydraulic cylinder 3 of the valve (s). valves 2.
• the selector casing 66 is also traversed longitudinally by one or more conduits which connect the closing collector 69 with the inlet (s) 7 of the volumetric hydraulic pump 4.
• the opening manifold 68 makes it possible to connect the conduits passing longitudinally through the selector housing 66 which must be connected to the same pump outlet 6.
• the pump outlet 6 is connected to the opening manifold 68 by a conduit which passes through the shutter housing 65.
• the closing collector 69 makes it possible to connect the conduits passing longitudinally through the selector housing 66 which must be connected to the same pump inlet 7.
• the pump inlet 7 is connected to the closing manifold 69 by the conduits which pass respectively through the selector housing 66 and the shutter housing 65.
• valve opening advance fork 61, the valve lifting fork 62 and the valve closing delay fork 63 are operated in translation by electric motors controlled by a computer which are connected to said forks 61, 62 and 63 by means of transmission.
• the pump outlet orifice (s) 29 which are closed off by the protrusions 28 of the shutter rotor 27 open out inside the common housing which comprises in particular the common shaft 59, said common housing constituting a closed chamber connected: *> to the lubricating oil sump of the engine 72 by means of a conduit,
• the same conduit connected to the high pressure hydraulic circuit 10 can simultaneously supply several hydraulic cylinders 3 through a flow divider which provides a lift substantially identical to the valves 2 actuated by said hydraulic cylinders 3.
• Figure 1 illustrates the block diagram of the device according to a four-valve configuration (for example to actuate the four intake or exhaust valves of a four-cylinder engine). It can be seen there that when no valve is to be opened by either of the hydraulic cylinders 3, the volumetric hydraulic pump 4 delivers hydraulic fluid from the low pressure circuit 9 - here the engine lubrication circuit - via the pump inlet check valve 26 and to the lubricant sump of the engine 58 via the pump outlet shutter 8 then open.
• valve opening selector 11 places the hydraulic cylinder 3 of said valve in relation to the high pressure circuit 10 coming from the output of the positive displacement hydraulic pump 4.
• the pump outlet shutter 8 then closes the pump outlet conduit 32 which raises the pressure in the high pressure circuit 10 so that the hydraulic cylinder 3 opens the selected valve.
• the pump outlet shutter 8 reopens the pump outlet duct 32 which stops the valve from lifting because the pressure of the high pressure circuit 10 upstream of the opening check valve 24 becomes lower than that prevailing in the chamber of the hydraulic cylinder 3 due to the action of the valve return spring.
• valve closing selector 25 which, at the chosen moment, puts the hydraulic cylinder 3 of said valve in relation to the inlet of the positive displacement hydraulic pump 4 via the high pressure circuit 10.
• the volumetric hydraulic pump 4 again delivers hydraulic fluid from the low pressure circuit 9 to the lubricant sump of the engine 58 via the pump inlet check valve 26.
• Figure 2 is a schematic representation of a circuit whose operation is identical to the previous one, but which is intended to actuate the 8 intake or exhaust valves of a four-cylinder engine with two intake or exhaust valves per cylinder.
• a vane pump with a single rotor but provided with an interior cam defining two isolated inputs and two outputs can be used as illustrated in FIG. 8.
• the pump outlet shutter 8, the valve opening selector 11 and the valve closing selector 25 can be produced by means of solenoid valves, but the fragility, the lack of robustness and the lack of regularity of operation of said valves solenoid valves in the context of a heat engine make such achievements difficult.
• FIGS. 15 to 21 which provides the reliability and the constancy of operation sought in motorization.
• the device shown in these figures is particularly intended for actuating the eight intake or exhaust valves of a four-cylinder engine with two intake valves or two exhaust valves per cylinder. Variants of such a device for other engine configurations will be readily apparent to those skilled in the art.
• the common shaft 59 is rotated by the engine 12 by means of the pulley 74 rotating at the same speed as a conventional camshaft, i.e. at half the speed of the crankshaft 5 of the engine 12, here in the clockwise when the device is seen on the pulley side 74.
• the entire device can be placed in place of the camshaft which it replaces (for example, the intake camshaft) and can be driven, as shown in figure 9, by the engine timing belt with another camshaft (for example, the exhaust camshaft), or else being driven by said belt as shown in figure 10 another identical device.
• the camshaft which it replaces for example, the intake camshaft
• another camshaft for example, the exhaust camshaft
• the volumetric hydraulic pump 4 is of the fin type with an internal cam defining two pump inputs 7 and two pump outputs 6 which do not communicate with each other, the pump inlet non-return valves 26 are connected to the low pressure circuit 9 by the occurrence, the pressure lubrication circuit of the motor 12, and consist of balls maintained in abutment on their seat by a spring.
• the common shaft 59 is provided with helical splines 60, these splines rotating the shutter rotor 27, the opening selector rotor 38 and the closing selector rotor 47.
• the shutter rotor 27 and the aperture selector rotor 38 remain phase with respect to each other because they are integral in rotation with the same sleeve 37 which guarantees a constant duration between the selection of a valve 2 and the start of shutting off the pump outlet 6. It can be seen that the operation of the pump shutters 8, of the valve opening selector 11, and of the valve closing selector 25 is necessarily synchronized because they are all driven by the common shaft 59.
• the pump outlet shutters 8 are here two placed diametrically opposite in the casing, and each block one of the two pump outlets 6 of the positive displacement hydraulic pump 4, each pump outlet 8 being assigned exclusively to opening either of the valves
• the two pump inputs 7 are assigned exclusively to the closing either of the 2 pair valves or of the odd 2 valves of the cylinders of the engine 12.
• the shutter rotor 27 comprises four protrusions 28 of variable profile placed every ninety degrees.
• valve lifting fork 62 makes it possible to control the lifting height of the valves 2, said fork being operated by an electric motor not shown, controlled by a computer not shown.
• the start point for opening the valves 2 can be controlled independently of the lifting of the valves 2 by moving the opening sleeve 37 in longitudinal translation relative to the common shaft 59 by means of the valve opening advance fork. 61.
• the valve opening advance fork 61 is operated by an electric motor not shown, controlled by a computer not shown.
• valve opening selector 11 and the valve closing selector 25 both fall under the same operating principle.
• the cam 39 of the opening selector actuates in opening a valve opening distributor 40 every ninety degrees of rotation of the common shaft 59, that is to say every hundred and eighty degrees of rotation of the crankshaft 5, in accordance with the requirements of a four-cylinder engine operating according to the four-stroke cycle of Otto or Beau de Rochas.
• Each valve opening distributor 40 makes it possible to simultaneously open or close the conduits 42 for supplying the hydraulic fluid to the hydraulic jacks 3 of a valve 2 pair and of an odd valve 2 of the same cylinder.
• the valve closing start point 2 is controlled by moving the closing selector rotor 47 in longitudinal translation relative to the common shaft 59 by means of the valve closing delay fork 63.
• the common casing may comprise a base in which is housed at least one hydraulic cylinder 3, said base being fixed on the cylinder head of the engine 12 so that each hydraulic cylinder 3 is in contact with the upper end of the tail of the corresponding valve 2 of said motor 12 and can actuate said valve.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Valve Device For Special Equipments (AREA)
• Fluid-Pressure Circuits (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=30011407

Family Applications (1)

Country Status (10)

Families Citing this family (10)

Family Cites Families (5)

• 2002
  • 2002-07-23 FR FR0209323A patent/FR2842867B1/fr not_active Expired - Fee Related
• 2003
  • 2003-07-18 WO PCT/FR2003/002271 patent/WO2004011780A1/fr not_active Ceased
  • 2003-07-18 ES ES03750820T patent/ES2261965T3/es not_active Expired - Lifetime
  • 2003-07-18 EP EP03750820A patent/EP1543221B1/de not_active Expired - Lifetime
  • 2003-07-18 AU AU2003269033A patent/AU2003269033B2/en not_active Ceased
  • 2003-07-18 DE DE60304589T patent/DE60304589T2/de not_active Expired - Lifetime
  • 2003-07-18 AT AT03750820T patent/ATE323217T1/de not_active IP Right Cessation
  • 2003-07-18 US US10/521,739 patent/US7162982B2/en not_active Expired - Fee Related
  • 2003-07-18 CA CA2492844A patent/CA2492844C/fr not_active Expired - Fee Related
  • 2003-07-18 JP JP2004523855A patent/JP4260743B2/ja not_active Expired - Fee Related

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events