Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/16—Rectilinearly-movable armatures
  • H01F7/1607—Armatures entering the winding
  • H01F7/1615—Armatures or stationary parts of magnetic circuit having permanent magnet
• • 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
• • 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
  • F01L2009/2105—Valve-gear or valve arrangements actuated non-mechanically by electric means actuated by solenoids comprising two or more coils
  • F01L2009/2109—The armature being articulated perpendicularly to the coils axes
• • 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
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L2820/00—Details on specific features characterising valve gear arrangements
  • F01L2820/03—Auxiliary actuators
  • F01L2820/031—Electromagnets
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/121—Guiding or setting position of armatures, e.g. retaining armatures in their end position
  • H01F7/122—Guiding or setting position of armatures, e.g. retaining armatures in their end position by permanent magnets

Definitions

• the present invention relates to an electromagnetic actuating device according to the preamble of claim 1.
• Such a device is well known, for example in the form of actuating devices with electro-holding magnets, and is used for a variety of purposes.
• the basic principle is that a piston as an actuating element, which has an engagement area at the end for the intended actuating task, is guided in a housing and can typically be moved out of the housing against the force of a return spring by means of an electromagnet provided in the housing.
• FIG. 3 illustrates such a known actuating device in the side sectional view: a piston element 10, guided in a housing 12 and biased against the force of a return spring 14, has an engaging area 16 on one end that protrudes from the housing 12 and the other end a pressed-on hollow cylindrical armature 18, which can be moved along a cylindrical running surface in a yoke element 20 of an electromagnet (realized with coil 22 in the coil housing 24) by a predetermined stroke, as a result of which the engagement area 16 (FIG. 3 shows the retracted or inserted operating state) emerges from the engagement-side housing end.
• the constructional implementation of such a device is complex and, in particular with regard to fits and tolerances, not uncritical: for manufacturing and assembly, the tolerances of the bearings involved (for example also bearings 26) apply. as well as the running surfaces, and also the mechanical structure, for example with regard to the conical region 28 adapted to the magnetization characteristic, is not without problems. Since, in addition, the device shown in FIG. 3 for setting, ie pushing the engagement area 16 out of the housing requires permanent signal application to the electromagnet, further control and electrotechnical problems arise.
• permanent magnet means typically implemented as a disc-shaped permanent magnet corresponding to a cylindrical outer shape of the actuating device, are used and the properties of such a permanent magnet are used in several ways: on the one hand, the permanent magnet serves to hold the actuating element in a (retracted) idle state by interacting with the Keep the core area securely in the housing.
• the permanent magnet when the coil device according to the invention is excited to generate an opposing electromagnetic field, the permanent magnet has a repulsion effect and thus driving the actuating element out of an associated housing, since, according to the invention, the electromagnetically generated opposing field with the opposing force acts repulsively on the permanent magnet and then produces the feed of the actuating element.
• the permanent magnet also offers the possibility of returning the actuating element to its rest position at the core area when the opposing electromagnetic field is deactivated (ie switching off the coil current).
• a bistable actuating device is created in an extremely simple and effective manner, which only needs a one-time pulsed current application to the coil device to leave the rest position and lead out the actuating element and as soon as the actuating element is extended and the permanent magnet has a sufficiently large distance as a result of the repulsive effect described to the core area, ensures a stable extension state even when the coil means is de-energized.
• the actuating means can then be re-introduced into the idle state either by external actuation of the actuating element (via the engagement area), additionally or alternatively by suitably reversed polarity control of the coil device, correspondingly supported by an attractive force effective from a predetermined distance from the core area permanent magnets.
• the actuating device according to the present invention also has significant simplifications and cost advantages in production allows.
• the actuating device it is particularly preferred to implement the actuating device according to the invention with a force accumulator designed as a spring, however, in contrast to the prior art used as a generic, here the spring force preferably in the extension direction of the actuating element and thus the Counteracts magnetic force of the permanent magnet.
• the piston can in particular be carried out quickly and reliably from the housing as soon as the holding force of the permanent magnet has been overcome by means of the coil device.
• this energy accumulator can be implemented either as a compression spring or as a tension spring.
• the stationary elements i. H.
• the core area and the coil device designed to be ring-shaped or cylindrical and accommodated in a cylindrical housing, in such an implementation it makes sense to implement the permanent magnet means as disk-shaped permanent magnet bodies which are approximately matched to an effective surface of the core area.
• a protective ring is preferably provided at the edge, which according to a further development is formed from a non-conductive material, such as plastic, and has an intended encapsulation or encapsulation effect.
• actuating device in the motor vehicle sector, and there in particular for engine control.
• a variable camshaft control can be realized in a way that is favorable in terms of control technology, the present invention being distinguished by excellent mechanical actuating properties, including short actuating times and reliable actuating movements, with a simplified electronic control requirement.
• the use in connection with a camshaft control also offers the structurally particularly elegant solution, not only to limit an effective stroke of the actuating element by a groove base of a corresponding actuating partner on the camshaft (or another element), but also to initiate the introduction operation, perform an initial lifting movement of the actuating element back towards the core area.
• the present invention creates the possibility of combining an electromagnetic actuating device for a low-power actuating or switching operation, by no means limited to the preferred, but not exclusively provided translatory actuating operation, with reliable mechanical operating properties and simple construction and simple adjustment. Furthermore, while operation in connection with a camshaft control is a preferred use of the present invention, the possible uses seem to be almost unlimited, in particular with regard to the possibility of enabling bistable actuation and switching operation with low power.
• FIG. 1 shows a longitudinal section through an electromagnetic adjusting device according to a first preferred embodiment of the present invention
• FIGS. 2 and 3 a perspective view of the overall device according to FIGS. 2 and 3: a view in longitudinal section analogous to FIG. 1 of a generic actuating device, as known from the prior art.
• a cylindrical housing section 30 receives a core 32 made of magnetic material, which is enclosed by a coil 36 wound on a coil former 34.
• the core 32 forms an i. w. flat flat side for cooperation with a disc-shaped permanent magnet 38, and a spiral spring 40 designed as a compression spring is held centrally in the core 32.
• disks 48, 50 made of magnetically conductive material are provided on both sides of the disk-shaped permanent magnet (made of common magnetic material, e.g. Nd-Fe), the structure consisting of the first Disk 48, permanent magnet disk 38 and second disk 50 is connected to one another by means of a thin adhesive film and thereby has a certain pulse-damping effect.
• the arrangement is surrounded by a plastic ring 52, which in particular has the task of preventing the flaking of material from the (brittle) permanent magnet disk or the penetration of fragments or dirt bodies into the barrel. or to prevent the range of movement of the actuating device shown;
• the respective edges of the permanent magnet (or of the plastic ring comprising it) and of the disks 48, 50 form a piston circumferential surface for a running surface formed in the interior of the housing section 30.
• a two-part housing is created as a double cylinder, cf. Fig. 2, wherein the housing portion 30 has a one-piece mounting flange 54 and the sleeve portion 46 as a separate Housing part is preferably made of non-magnetic steel and is fitted into the housing section 30. 2 additionally schematically illustrates cable ends 56 for supplying power to the coil 36.
• FIG. 2 In operation of the arrangement according to FIG. 1, FIG. 2 without current being applied to the coil 36, the arrangement of pistons 42 with fixed disks 48, 38, 50 is first held on the core 32 by the action of the permanent magnet 38. It is only when current is applied to the coil 36 that a magnetic field is created which counteracts the field of the permanent magnet 38, displaces or directs it into the disks 48, 50 and thus leads to repulsion; hereby, supported by the force of the spiral spring 40 (which as such is not able to overcome the pure adhesive force of the permanent magnet 38), the piston in the illustration in FIG. 1 is driven out to the right out of the sleeve section 46 of the housing and thus fulfills its intended switching or actuating function.
• the piston can be retracted or the actuation process reversed by reversing the polarity of the coil current to be applied, which acts on the permanent magnet 38 or the associated disks 48, 50, causing the piston - against the force of the spring 40 - is brought back to the starting position according to FIG. 1. Additionally or alternatively, this movement can be triggered by an external thrust force on the piston 42 in the direction of the rest position shown in FIG. 1, until the permanent magnet can then bring about the further return by its magnetic force. Such movement can take place, for example, by an actuating partner interacting with the actuating device, for example an appropriately designed engagement groove.
• the present invention has a particularly useful and effective practical application in connection with the control of internal combustion engines, in particular the (variable) cam setting for a camshaft.
• a suitable groove for the engagement area 44 of the piston 42 would not only limit a maximum stroke of the piston 42 by its appropriately dimensioned groove base (so that the disk 50 does not move up to the stop formed by an inner surface of the sleeve section 46), this groove base could also be in suitably generate the release or return pulse for the above-described return of the piston to the starting position according to FIG. 1.
• the present invention is not limited to the specifically described embodiment and the application example of internal combustion engine control. It is thus particularly encompassed by the present invention to implement translatory movements other than those shown in FIG. 1, FIG. 2 as actuating devices; it is particularly conceivable that an embodiment of the invention (not shown in the figures) performs a rotary movement.
• the structural arrangement of the individual units within the actuating device is not specified; not only can the spiral spring 40 shown in FIG. 1 be formed at another location (also, for example, as a tension spring), or the coil area can be arranged opposite to the piston.
• the present invention creates a wide range of possibilities for combining an actuating device which acts mechanically with the least effort and extremely reliably, with simplified electrotechnical control and, in particular, also low-power bistable operation.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Valve Device For Special Equipments (AREA)
• Reciprocating, Oscillating Or Vibrating Motors (AREA)
• Electromagnets (AREA)
• Fluid-Damping Devices (AREA)
• Vehicle Body Suspensions (AREA)
• Lift-Guide Devices, And Elevator Ropes And Cables (AREA)
• Magnetically Actuated Valves (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=7961223

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (129)

Family Cites Families (11)

• 2001
  • 2001-09-01 DE DE20114466U patent/DE20114466U1/de not_active Expired - Lifetime
• 2002
  • 2002-08-30 DE DE10262354.6A patent/DE10262354B4/de not_active Expired - Lifetime
  • 2002-08-30 EP EP02781178A patent/EP1421591B1/fr not_active Revoked
  • 2002-08-30 DE DE50211017T patent/DE50211017D1/de not_active Expired - Fee Related
  • 2002-08-30 WO PCT/EP2002/009677 patent/WO2003021612A1/fr active IP Right Grant
  • 2002-08-30 AT AT02781178T patent/ATE374997T1/de not_active IP Right Cessation
  • 2002-08-30 DE DE10240774A patent/DE10240774B4/de not_active Expired - Lifetime
  • 2002-08-30 ES ES02781178T patent/ES2292826T3/es not_active Expired - Lifetime
• 2004
  • 2004-03-01 US US10/790,511 patent/US6967550B2/en not_active Expired - Lifetime

Non-Patent Citations (1)

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