JP6458132B2 - solenoid valve - Google Patents

Description

  The present invention particularly relates to an electromagnetic valve used as a device for an internal combustion engine. Such a device for an internal combustion engine can be an injection device or a device for exhaust aftertreatment in which a suitable medium is injected in the exhaust line. In particular, the present invention relates to the injector field of an injection device for a fuel-air-compression type spark-ignition internal combustion engine in which fuel, particularly gasoline, is directly injected into a combustion chamber of the internal combustion engine. In that case, direct needle drive can be realized. However, the electromagnetic valve can also be configured as a servo valve. In that case, application to an air compression type self-ignition internal combustion engine can be envisaged.

  German Offenlegungsschrift DE 10 201 108 9999 discloses an electromagnetic valve, in particular an electromagnetic control valve for a high-pressure fuel pump. A known solenoid valve has a pole iron core and an armature movable in the axial direction, and the end face of the pole iron core forms a stopper for the armature. In this case, the pole iron core is made of a ferritic material, particularly ferritic stainless steel. Furthermore, the end surface of the pole iron core that forms the stopper exists in a portion manufactured by plastic cold working. The stopper can be provided with a hard chrome film. At that time, the armature is inserted into the ring-shaped non-magnetic component. This ring-shaped nonmagnetic part surrounds the armature in a partial region in the axial direction, and further surrounds the ferrite pole iron core having a cold-worked end surface forming a stopper in a partial region.

  German Patent Application Publication No. 19827267 discloses a fuel injection valve for high-pressure injection of fuel from a high-pressure accumulator into a combustion chamber of an internal combustion engine. Known fuel injection valves reduce or build fuel pressure in the control chamber (injection position) via a throttle valve having at least one throttle valve-channel portion defined by a channel wall ( A solenoid valve used for the closed position). The electromagnetic valve has a spring acting in the closing direction and an electromagnetic coil, and when the electromagnetic coil is excited, it causes suction of the valve element, thereby opening the throttle valve.

  Thereby, in the configuration of the electromagnetic valve described above, magnetic separation of the magnetic circuit by the correspondingly configured components is provided in the region of the gap between the inner pole and the armature. This component can be formed as a non-magnetic part in the shape of a ring, as is the case with DE 102011089999. An inner pole can be fixed to the separation part made of a non-magnetic material.

  The solenoid valve according to the present invention having the features of claim 1 is improved, in particular, when the electromagnetic coil is energized, and the attraction force for operating the armature generated through the magnetic circuit is increased. There is an advantage that it can be configured.

  By means of the dependent claims, an advantageous development of the solenoid valve according to claim 1 is possible.

  This particularly increases the magnetic holding force for holding the armature at the inner pole. In that case, a plurality of non-magnetic separators and / or a plurality of magnetic conductors can be used. However, in a preferred configuration, exactly one non-magnetic separator and exactly one magnetic conductor are provided. This is already advantageous with respect to the magnetic circuit or to the magnetic field lines generated in the magnetic circuit when the electromagnetic coil is energized by the appropriate configuration and arrangement of the non-magnetic separator and the conductive material. Makes it possible to influence.

  The separator may be configured as a separator having low magnetic conductivity.

  The magnetic conductor is made of at least a magnetic material. In this case, the magnetic material is appropriately selected from the provided magnetic materials, and in particular, a ferrite-based material can be used.

  In the structure of the separator and the magnetic conductor described above, it is important to have a favorable influence on the magnetic field lines for the magnetic flux. In this case, the inner pole is advantageously connected to at least a substantially magnetic conducting body and the outer pole is connected to at least a substantially non-magnetic separating body. More preferably, the non-magnetic separator is at least substantially formed of a material having an austenitic structure. Additionally or alternatively, it is advantageous if the magnetic conductor is formed at least substantially of a ferromagnetic material. In so doing, the magnetic conductor can advantageously be inserted into a non-magnetic separator. In this way, the magnetic conductor can be fixedly joined on the one hand to the non-magnetic separator and on the other hand to the inner pole.

  It is also advantageous that the magnetic conductor has a ring-like structure and / or is formed in a sleeve shape. Furthermore, it is advantageous for the non-magnetic separator to have a ring-like structure and / or be formed into a sleeve shape. Thereby, in particular, the non-magnetic separator can be configured as a separation ring. Furthermore, the magnetic conductor can in particular be configured as a magnetic ring fixedly joined to such a separation ring. At this time, the magnetic conducting body further has a connecting lip extending in the axial direction in which the radial thickness of the magnetic conducting body is reduced, and the non-magnetic separating body has a void existing inside. However, it is advantageous when the connecting lip of the magnetic conductor is inserted into the space. As a result, a cylinder jacket-shaped inner surface of a combined body composed of the separator and the magnetic conductor is generated particularly in the junction region between the magnetic conductor and the non-magnetic separator. This further allows the purposeful positioning of the inner pole with high accuracy and the tolerances associated with this in the construction of the combination.

  Amplification of the magnetic attractive force acting on the armature when the electromagnetic coil is energized at least over the working stroke range of the armature is a given working gap between the inner pole and the armature. It is also advantageous for the magnetic conductor to be configured as achieved on the basis of the formation of a magnetic circuit made possible by the magnetic conductor. That is, when a given working gap is provided between the inner pole and the armature, a configuration in which a non-magnetic separator is provided instead of the conductive material is provided depending on the configuration of the conductive material. In comparison, amplification of the magnetic attractive force on the armature is achieved. In the working stroke range, the above amplification is achieved for each given working gap. The total possible stroke range of the solenoid valve can in some cases be greater than the working stroke range.

  However, in a modified configuration, amplification may be achieved only for particularly relevant sections of the working stroke range. This may be sufficient for any application case. In particular, the magnetic conducting body is a magnetic conducting body in which the magnetic attraction force acting on the armature when the electromagnetic coil is energized is reduced in a small working gap or a large working gap within the working stroke range of the armature. It can be configured to be achieved based on the magnetic circuit that is possible. Thus, according to the configuration, amplification of the magnetic holding force when the armature is attracted or amplification of the attractive force at the start of the operation can be achieved.

  However, preferably, amplification of the magnetic attractive force acting on the armature when the electromagnetic coil is energized over the entire working stroke range of the armature is achieved.

  Furthermore, the non-magnetic separator has a spacing region through which the magnetic material is separated from the outer pole, and the armature is partially present in the spacing region in the axial direction but in the axial direction. It is advantageous to arrange them so that they are always separated from the magnetic conductor. Thereby, the armature is always separated from the magnetic conductor over the entire working stroke range of the armature. This is therefore also true in some cases when the work gap has disappeared or the work gap has almost disappeared. As a result, an indirect magnetic circuit between the inner pole and the armature via the magnetic conductive material filling the gap is prevented. This ensures a highly reliable functional configuration even when the work gap is small or almost disappeared.

  Therefore, it is also advantageous that the magnetic conductor is disposed axially in the inner pole and the non-magnetic separator extends axially beyond the end face of the inner pole facing the armature. In particular, the outer pole can be formed at least in part by a valve housing. In some configurations, the inner pole can also be formed at least in part by the valve housing. Normally, the valve housing is composed of a plurality of parts, so that the individual housing parts are made of a magnetic material, and the other housing parts can be made of at least a non-magnetic material.

Preferred embodiments of the present invention will be described in detail in the following description with reference to the accompanying drawings in which corresponding components are designated by the same reference numerals.
The schematic sectional drawing by the excerpt of the solenoid valve corresponding to one Example of this invention is shown. The figure which extracted the part of the solenoid valve shown by II in FIG. 1 corresponding to the same embodiment of this invention is shown. The graph explaining the functional form of the solenoid valve of this invention corresponding to a possible structure is shown.

  FIG. 1 shows a schematic cross-sectional view of an excerpt of a solenoid valve corresponding to an embodiment of the present invention. The solenoid valve 1 is used in particular as an internal combustion engine device. At that time, the solenoid valve 1 is used as a fuel injection valve for injecting fuel into the combustion chamber of the internal combustion engine. However, the solenoid valve 1 can also be used for injecting a medium for exhaust aftertreatment into the exhaust line of the internal combustion engine or for other purposes in the framework of the internal combustion engine device. Furthermore, the solenoid valve 1 is suitable for other application cases in a correspondingly adapted configuration.

  The electromagnetic valve 1 has an outer pole 2 and an inner pole 3. Furthermore, the solenoid valve 1 has a housing 4 that can be configured by a plurality of portions. For the sake of simplicity, only the housing part 4 is shown. The inner pole 3 is inserted into the housing 4. Here, a mechanical connection between the inner pole 3 and the outer pole 2 is formed. The outer pole 2 is a component of the housing part 4 in this embodiment.

  The housing part 4 is provided with a valve seat body 5 in which a valve seat surface 6 is formed. Furthermore, a valve needle 7 is arranged inside the housing part 4. In the present embodiment, a valve closing body 8 disposed corresponding to the valve seat surface 6 is formed on the valve needle 7. At that time, the valve needle 7 is directly operated by the electromagnetic valve 1. At that time, the valve closing body 8 of the valve needle 7 cooperates with the valve seat surface 6 to form a seal portion.

  The valve needle 7 is guided through the valve needle guide 10 along the axis 9. In so doing, usually at least two such valve needle guides 10 are provided along the axis 9. Fuel can be guided through the fuel channel 12 into the interior space 11 of the housing part 4. For this purpose, the solenoid valve 1 has a fuel connection pipe 13, and a fuel pump or a common rail (Common-Rail) can be connected to the fuel connection pipe 13, for example. When the valve closing body 8 is operated, the valve closing body 8 is lifted from the valve seat surface 6, so that fuel is passed from the inner space 11 of the housing part 4 via the injection holes 14 to the internal combustion engine. It can be injected into the associated fuel chamber, intake manifold, pre-combustion chamber or the like.

  In a modified configuration, a direct drive of the valve closing body 8 can also be envisaged. In so doing, separate valve needles can be provided for the solenoid valve 1 and for closing the injection hole 14 in the valve seat surface 6. Here, the electromagnetic valve 1 provided with the valve needle 7 functions as the servo valve 1. Yet another possibility is a hydraulic coupling, possibly allowing a stroke transmission.

  Furthermore, the solenoid valve 1 can also be used for injecting or metering other media as fuel. In that case, it is possible in a corresponding manner, for example, to connect a pump to the connecting tube 13, and the medium associated therewith is pumped into the internal space 11 via the channel 12. In particular, this allows the medium for exhaust aftertreatment to be metered.

  The fuel or medium may be a gaseous fuel or medium as well as a liquid fuel or medium. For example, natural gas can be used as the fuel.

  The electromagnetic valve 1 further has an electromagnetic coil 20. The electromagnetic coil 20 is connected to the electrical connection portion 22 via the electric wire 21. The electrical connection 22 can be connected to a control device for a fuel injection device, for example. However, the control unit of the electromagnetic coil 20 can be completely or partially incorporated in the electromagnetic valve 1.

  A valve spring 23 is arranged in the inner pole 3, and this valve spring 23 is supported by a flange 24 of the valve needle 7. In this embodiment, in the direction of the seal portion along the shaft 9. A load is applied to the valve needle 7.

  Further, an armature 25 arranged corresponding to the end face 26 of the inner pole 3 is provided.

  When the electromagnetic coil 20 of the solenoid valve 1 is energized, a magnetic circuit (Magnetschlus) that passes through the inner pole 3, the armature 25, and the outer pole 2 is generated. Thereby, the armature 25 is operated in the direction of the end face 26. At this time, this operation is performed against the preload of the valve spring 23. During this operation, the armature 25 acts on the valve needle 7 via the flange 24, so that the seal portion between the valve closing body 8 and the valve seat surface 6 is opened.

  Below, the structure of the solenoid valve 1 is demonstrated, referring FIG.

  FIG. 2 shows a diagram extracted from the portion of the electromagnetic valve 1 indicated by II in FIG. 1 corresponding to the same embodiment. The housing part 4 is provided with a separator 32 and a magnetic conductor 33. At that time, the separator 32 is joined to the base 31 of the housing part 4. In this embodiment, the separator 32 is non-magnetic. A magnetic conductor 33 is fixed to the separator 32. In the present embodiment, the separating body 32 and the magnetic conducting body 33 extend along the axis 9 substantially in the axial direction starting from the base portion 31. At this time, the separating body 32 and the magnetic conducting body 33 have a radial thickness, and this radial thickness is along the axial extension of the combined body composed of the separating body 32 and the magnetic conducting body 33. Change. Alternatively, the thickness may be constant. In any case, in the present embodiment, a cylinder jacket-shaped inner surface 34 is provided, and the cylinder jacket-shaped inner surface 34 is composed of the separator 32 and the magnetic conductor 33, that is, the separator 32 and the magnetic conductor 33. It extends over the combined body. As a result, a stepless transition between the non-magnetic separator 32 and the magnetic conductor 33 is generated on the cylinder jacket-shaped inner surface 34. Furthermore, the inner surface 34 according to the configuration of the cylinder jacket shape also extends on the connection region between the base 31 on the one hand and the separating body 32 and the magnetic conductor 33 on the other hand. The production of the housing part 4 can be produced, for example, by a 2K3S (2 components, 3 injections) or 3K3S (3 components, 3 injections) MIM (metal injection molding) process. At that time, the non-magnetic base material of the separator 32 is injection-molded on the injection-molded magnetic base material (Rohling) of the base 31, and the magnetic base material of the magnetic material 32 is formed thereon. Is injection molded. Thereafter, the workpiece manufactured from the three partial injection moldings is sintered into the housing part 4.

Thus, in FIG. 2, the elements inside the housing part 4, in particular the armature 25 and the inner pole 3, in a possible advantageous configuration, in particular with respect to the separation body 32 and the base 31, the separation body 32, Positioned relative to the magnetic conducting body 33 and possible advantageous divisions of the housing part 4 into.

  The inner pole 3 is joined to the magnetic conductor 33 and is preferably press-fitted into the magnetic conductor 33 and welded to the magnetic conductor 33. The outer pole 2 is joined to a non-magnetic separator 32. At that time, the outer pole 2 is formed by at least one component of the base 31.

  In the present embodiment, the non-magnetic separator 32 is preferably formed of a material having an austenite structure. However, with regard to the functional form of the present invention, other materials can be envisaged that realize the non-magnetic property or the low magnetic property of the non-magnetic or low-magnetic separator 32. The magnetic conductor 33 is preferably made of a ferromagnetic material. In general, the magnetic conductor 33 is formed of a material that has an advantageous influence on the magnetic field lines in the functional form of the present invention.

  The magnetic conductor 33 preferably has a ring-like structure and is preferably formed in a sleeve shape. Further, the non-magnetic separator 32 preferably has a ring-like structure and is preferably formed in a sleeve shape. The magnetic conducting body 33 preferably has a connecting lip 35 extending in the axial direction in which the radial thickness of the magnetic conducting body 33 is reduced. Non-magnetic separator 32 has a correspondingly adapted configuration. In so doing, the non-magnetic separator 32 has an inner cavity 37 for the magnetic conductor 33 or for the connecting lip 35 of the magnetic conductor 33. A connecting lip 35 of a magnetic conducting body 33 is inserted into a space 37 inside the non-magnetic separating body 32. In that case, joining is realized in an appropriate manner. For example, the magnetic conductor 33 is press-fit into a non-magnetic separator 32 and welded to the separator 32, or manufactured as part of a 2K3S or 3K3S MIM process. Thereby, the magnetic conductor 33 is inserted into the non-magnetic separator 32.

  The non-magnetic separator 32 has a gap region 38 having an axial length 39, and the magnetic conductor 33 is separated from the outer pole 2 through the gap region 38. The armature 25 partially exists in the spacing region 38 in the axial direction, but is arranged so as to be always separated from or spaced from the magnetic conducting material 33 in the axial direction. This ensures the above separation for each possible position of the armature 25 within the working stroke range. The magnetic conducting body 33 is disposed in the inner pole 3 in the axial direction, and in this case, the non-magnetic separating body 32 is preferably disposed on the inner pole 3 facing the armature 25 in the axial direction. It extends beyond the end face 26. In the present embodiment, the spacing region 38 is connected to the junction region 40 of the separator 32 and the magnetic conductor 33 in which the separator 32 and the magnetic conductor 33 are joined to each other. The connection area 40 has an axial length 41. Further, a purely magnetic region 42 of the magnetic conductor 33 is connected to the connection region 40 in the axial direction. This purely magnetically conductive region 42 has an axial length 43. The axial lengths 39, 41, 43 of the separating body 32 and the magnetic conducting body 33 are the axial length 39 of the spacing area 38, the axial length 41 of the connecting area 40, and a purely magnetic conducting area. It is obtained from the sum of the axial length 43 of 42. Further, a splicing portion 44 extending over the axial length 45 is provided in contact with the outer pole 2. The separating body 32 is joined to the added portion 44. This realizes structural and connection technical advantages.

  FIG. 3 shows a graph for explaining the functional form of the electromagnetic valve 1 corresponding to the possible configuration of the electromagnetic valve 1. Here, the vertical axis represents the magnetic force F in Newton (N), and the horizontal axis represents the work gap s in meters (m). A characteristic curve 46 is obtained for the solenoid valve 1 corresponding to a possible configuration of the invention, which characteristic curve 46 is divided into two ranges 47, 48. For comparison, a characteristic curve 50 divided into ranges 51 and 52 is shown. The division of the characteristic curve 46 into the ranges 47, 48 and the division of the characteristic curve 50 into 51, 52 are obtained by the intersection 53 of both characteristic curves 46, 50, which has an air gap of 60 μm and the forces associated therewith. It exists in the vicinity of 40N. The work stroke range 54 is preferably selected within a range from 0 μm to the work stroke s associated with the intersection 53. In other words, the configuration of the separating body 32 and the magnetic conducting body 33 preferably has a working stroke s for the intersection 53 (which can be assumed but is not realized at the time of driving) but is realized at the time of driving. To be outside the desired work stroke range 54.

The characteristic curve 50 corresponds to the configuration of the electromagnetic valve 1 in which the magnetic conducting body 33 is replaced with a part made of a non-magnetic material having the same configuration. Thus, the graph of FIG. 3 shows the mode of action of the magnetic conductor 33 and the non-magnetic separator portion 32 , that is, the mode of action of the combined body combined.

  In the range 47, the characteristic curve 46 exceeds the range 51 of the characteristic curve 50. Thereby, a larger magnetic force F is realized in a given working gap s. That is, the magnetic force F can be amplified particularly in the work stroke range 54.

  Outside the work stroke range 54, as can be seen from FIG. This is because the range 48 of the characteristic curve 46 is lower than the range 52 of the characteristic curve 50.

  Therefore, the separating body 32 and the magnetic conducting body 33 can amplify the magnetic attractive force F acting on the armature 25 when the magnetic coil 20 is energized over the working stroke range 54 of the armature 25. In a given working gap s between the inner pole 3 and the armature 25, it is configured to be achieved on the basis of the formation of a magnetic circuit made possible by the magnetic conductor 33.

  In the modified configuration of the solenoid valve 1, the amplification of the magnetic force F may be limited to one section of the work stroke range 54 in some cases. That is, in that case, the intersection point 53 exists in the work stroke range 54, or the work stroke range 54 extends beyond the intersection point 53. Thereby, according to the change of the electromagnetic valve 1, for example, the amplification of the holding force acting against the spring force that keeps the seal portion closed in the operated state can be achieved.

The invention is not limited to the described embodiments.

Claims (6)

An electromagnetic valve (1) comprising an outer pole (2), an inner pole (3), an electromagnetic coil (20), and an armature (25),
The inner pole (3) is connected to the outer pole (2) through at least one non-magnetic or low-magnetic separator (32) and at least one magnetic conductor (33), When the electromagnetic coil (20) is energized, a magnetic circuit is generated that passes through the inner pole (3), the armature (25), and the outer pole (2). (4), next to the outer electrode (2), said at least one separator (32), and, possess at least one magnetically conductive body (33),
The magnetic conductor (33) has a ring-like structure and / or is formed in a sleeve shape, and / or the separator (32) has a ring-like structure and / or in a sleeve shape. Formed,
The magnetic conductor (33) has a connecting lip (35) extending in the axial direction in which the radial thickness (36) of the magnetic conductor (33) is reduced, and the separator (32) is A space (37) existing inside, and the connection lip (35) of the magnetic conductor is inserted into the space (37);
The separator (32) and the magnetic conductor (33) are connected to each other without forming a step on the inner surface of the separator (32) and the inner surface of the magnetic conductor (33).
The separator (32) has an interval region (38) through which the magnetic conductor (33) is separated from the outer pole (2), and the armature (25) Partially located in the spacing region (38) but arranged so as to be always separated from the magnetic conductor (33) in the axial direction,
The magnetic conductor (33) is disposed in the inner pole (3) in the axial direction, and the separator (32) is axially directed toward the armature (25). ) that extends beyond the end face (26), the solenoid valve (1).   The inner pole (3) is at least substantially connected to the magnetic conductor (33), and the outer pole (2) is at least substantially the non-magnetic or low-magnetic separator (32). The solenoid valve according to claim 1, wherein the solenoid valve is connected to the solenoid valve.   The non-magnetic or low-magnetic separator (32) is at least substantially formed of a material having an austenitic structure, and / or the magnetic conductor (33) is at least substantially strong. The solenoid valve according to claim 1, wherein the solenoid valve is made of a magnetic material. The magnetically conductive material (33) comprises, characterized in that the or magnetically conductive non magnetic conductive is inserted into a lower separator (32), the solenoid valve according to any one of claims 1 to 3 . The magnetic conductor (33) is magnetically attracted to the armature (25) when the electromagnetic coil is energized over at least the work stroke range (54) of the armature (25). The magnetic circuit (33) allows the amplification of force (F) in a given working gap (s) between the inner pole (3) and the armature (25). based on the formation, and is characterized in that configured to be achieved, the solenoid valve according to any one of claims 1-4. The electromagnetic valve (1) according to any one of claims 1 to 5 , wherein the electromagnetic valve (1) is an electromagnetic valve used as a device for an internal combustion engine.

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