CN113474851A

CN113474851A - Electromagnetic drive mechanism and proportional solenoid valve equipped with same

Info

Publication number: CN113474851A
Application number: CN202080018156.6A
Authority: CN
Inventors: J·格尔哈茨; M·伦茨
Original assignee: Festo SE and Co KG
Current assignee: Festo SE and Co KG
Priority date: 2019-03-01
Filing date: 2020-02-28
Publication date: 2021-10-01
Also published as: WO2020178155A1; DE102019204839A1

Abstract

The invention provides an electromagnetic drive mechanism (2) and a proportional solenoid valve (1) equipped with the same. The drive mechanism (2) has a coil arrangement (25) which can be supplied with current and has two electromagnetic coils (26, 27) which are each laterally surrounded by a pole ring (36, 37) which serves for guiding the flux and which delimit an armature (13) which can be driven in a stroke movement (14). The armature (13) has an armature body (55) which serves for guiding the flux and which covers the two pole rings (36, 37) in a continuous manner in part axially and has at least one annular armature end section (72, 73) which has a circumferential surface which tapers conically towards the inside in the axial direction. When the coil arrangement (25) is supplied with current, the resulting coil magnetic field interacts with the permanent magnet field (34) of the permanent magnet (32) and causes a resulting drive force which is responsible for generating the stroke movement.

Description

Electromagnetic drive mechanism and proportional solenoid valve equipped with same

Technical Field

The invention relates to an electromagnetic drive having a stator, which has a current-carrying coil arrangement with two electromagnetic coils arranged coaxially to a main axis and spaced apart from one another and having a flux-conducting yoke arrangement with two flux-conducting pole rings which respectively laterally surround one of the two electromagnetic coils in a coaxial orientation at an outer side facing axially away from the other electromagnetic coil, and having an armature which is coaxially surrounded by the coil arrangement and which has a flux-conducting armature body which is passed through by the permanent magnet field of the permanent magnet of the drive in the same manner as the yoke arrangement of the stator, and which has two axially mutually opposite armature body end sections with cylindrical outer circumferential faces which are arranged adjacent to one of the two pole rings, the armature can be moved axially back and forth relative to the stator when the stroke movement is carried out due to the interaction of the permanent magnet field with the coil magnetic field, which can be brought about by controlled energization of the coil arrangement, and can be positioned in different stroke positions.

The invention further relates to a proportional solenoid valve designed for controlling a flow of a fluid, having a valve housing, a valve ring movable relative to the valve housing when a control movement is carried out, and an electromagnetic drive for generating the control movement of the valve ring.

Background

Such a proportional solenoid valve equipped with an electromagnetic drive of the type mentioned at the outset is known from DE 102012018566 a 1. The known drive mechanism has two electromagnetic coils arranged at an axial distance from one another, which are each laterally surrounded by a pole ring, which serves to guide the flux, on the outer sides facing away from one another, and between which an annular flux guide is furthermore arranged. The aforementioned components belong to a stator which is fixed in position with respect to the valve housing and which encloses an axially movable armature having an armature body which acts as a guide flux. The armature body comprises two parts which serve to guide the flux, between which parts a permanent magnet is arranged. The armature is provided at the end with a valve ring, which is biased into a closed position against a valve seat by means of a spring mechanism. The two electromagnetic coils are wound in opposite directions and are electrically connected in series, so that when a current is supplied, they generate two coil magnetic fields whose field lines run in opposite directions with respect to one another. The axial length of the armature corresponds to the clear (lichten) spacing between the two pole rings of the stator. The controlled passage of current through the electromagnetic coil can cause an interaction between the resulting coil magnetic field and the permanent magnet field of the permanent magnet, from which an axial drive force is obtained which acts on the armature, so that the armature can be driven into a stroke movement and can be positioned steplessly in different stroke positions. In this way, the solenoid valve can be operated with a proportional regulating action, which is advantageous for pressure-regulated or flux-regulated applications.

DE 102011115115 a1 discloses a valve mechanism, the stator of which has coils which are laterally surrounded axially on both sides by ring magnets. The coil encloses an armature which functions as a valve body and has a ferromagnetic armature body, the length of which corresponds to the clear distance between the two ring magnets.

A drive device known from DE 19900788 a1 has an axially movable drive part with a magnetizable section, which extends coaxially through an electromagnetic coil, which is laterally surrounded axially on both sides by annular magnets. In order to produce a stroke movement of the drive part, the electromagnetic coil can be supplied with current, so that an interaction with the permanent magnet field occurs which drivingly influences the section that can be magnetized.

DE 102009021639 a1 describes a solenoid valve having a solenoid coil arranged in a stationary manner at a valve housing, which is laterally surrounded axially on both sides by annular permanent magnets. The electromagnetic coil encloses an armature which carries the valve ring section opposite the valve seat and which can be driven into a stroke movement by a controlled current flow of the electromagnetic coil.

102004056236A 1 describes an electromagnetic drive mechanism formed from bi-stable reverse stroke magnets (Umkehrhubmagnet). The reverse-stroke magnet has a stator with two coils which are each laterally surrounded axially on the outside by a cover and between which a radially polarized annular magnet is arranged. The stator encloses an armature assembly having an axially movable cylindrical armature body into which the two covers are sunk at the end.

JP S60-84805 a describes a three-dimensionally stabilized electromagnetic device with an armature that can be moved, which can be stopped precisely in a neutral position.

Known electromagnetic drive mechanisms based on the magnetoresistive drive principle can only be used insufficiently for proportional applications because of the strong non-linearity in their force-travel characteristic.

Disclosure of Invention

The object of the invention is to provide a method for controlling a proportional solenoid valve, which allows a good proportional control action to be achieved with a large stroke range and simultaneously high power in the case of an electromagnetic drive and a proportional solenoid valve equipped therewith.

In order to solve this problem, according to the invention in an electromagnetic drive of the type mentioned at the outset, it is provided that the armature body in each stroke position of the armature with its two armature body end sections is immersed with only partial axial cover into the respectively adjacent pole ring, so that a radial annular gap is present between each armature body end section and the pole ring adjacent thereto, wherein the axial cover length and thus the axial annular gap length depend on the stroke position of the armature, wherein at least one of the two armature body end sections is designed annularly and has an inner circumferential surface which tapers conically from its free end to the axial interior, so that the radial thickness of the annular cross section of the armature body end section at right angles to the main axis decreases continuously toward its free end.

The object is also achieved according to the invention in the case of a proportional solenoid valve of the type mentioned at the outset in that its electromagnetic drive is designed in the manner mentioned above, wherein the valve ring is coupled to the armature in a driven manner for generating its control movement.

The electromagnetic drive is particularly suitable for use in a proportional solenoid valve, but can also be used for other drive tasks.

Within the electromagnetic drive, the armature body of the axially movably mounted armature, which has the property of guiding the flux, and the preferably annularly and symmetrically designed flux-guiding yoke assembly, which is arranged on the stator, are in magnetic interaction, wherein a permanent-magnetic pretensioning is produced by the additionally present permanent magnets. The armature body has a length such that it sinks with the two armature body end sections into the respectively adjacent pole ring independently of the stroke position currently occupied by the armature, so that an axial covering exists between each armature body end section and a partial length of the adjacent pole ring. A radial annular gap is formed between each pole ring and the immersed armature body end section, through which gap both the permanent magnet field of the permanent magnets and the coil magnetic field of the adjacent electromagnetic coil pass when a respective current is applied. In conjunction with the annular shape of at least one of the armature body end sections, at least in the length section coupled to the free end, having an internal conical shape, the armature body is also loaded with a resulting (resultierenden) axial drive force despite the radial magnet gap, which can be explained by the occurrence of magnetic leakage fields which arise as a result of the relatively small annular cross section of the armature body end section for the magnetic flux and which continuously decrease toward the free end of the armature body end section. As a result, according to the invention, a mixture of radial and axial components of the reluctance forces is used to generate a maximally proportional stroke-force characteristic curve by means of a special, conically tapering profile of at least one axial end section of the armature body. By the design according to the invention, a relatively linear, proportional behavior is obtained in the edge region itself. In addition, the combination with a permanent-magnet pretensioning enables particularly high dynamics with a small inductance. High dynamics are particularly pronounced if the permanent magnets belong to the stator according to a preferred embodiment and therefore do not contribute to the moving mass. The end section of the armature body, which is designed conically on the inside, is preferably designed in such a way that the conically tapering inner circumferential surface has a radial distance at each point from the central longitudinal axis of the armature body, which axis overlaps the main axis.

The inner cone formed in the at least one annular armature end section extends axially with an increasing (zunehmender) taper into the armature end section starting from the free end of the end face of the armature end section, wherein the inner cone preferably extends over the entire axial length of the annular armature end section, but can nevertheless be shorter and can transition into the hollow cylindrical length section.

Advantageous developments of the invention emerge from the dependent claims.

Preferably, the two armature end sections are of annular design and have an inner circumferential surface which tapers conically from the free end to the axial interior. The two armature body end sections are preferably identically constructed. By arranging the internally tapered armature body end sections on both sides, the driving force can be generated with a bistable functionality in the two axial directions. If only a single stable functionality is desired, which works for example by means of a spring return, in principle only a single-sided internal cone would suffice. In this case, the opposite side can be embodied, for example, cylindrically, however, also with a continuous, partially axial covering, which is present independently of the stroke position of the armature, by means of the adjacent pole ring.

The axial length of the armature body, which has the property of guiding the flux, is preferably selected such that in the middle stroke position of the armature (in which the two armature body end sections are immersed with the same axial cover length into the respectively adjacent pole ring), the axial cover length corresponds on both sides to 0.3 to 1.5 times the maximum possible stroke of the armature during its stroke movement. The axial length of the one-sided cover corresponds to the armature stroke in the case of the described arrangement, for example.

The cone angle of the conical inner circumferential surface of the armature body end section (which can also be referred to as the opening angle) is preferably in the range from 20 ° to 120 ° (each included), wherein the cone angle is in particular in the range from 40 ° to 80 ° (each included).

At its free end, the annular armature body end section is preferably flattened or rounded. Alternatively, the armature body end section can also terminate with an axially oriented edge.

The permanent magnet is expediently configured in the form of a ring, so that it can be referred to as a ring magnet. The permanent magnet is arranged in particular coaxially to the main axis.

It is considered to be particularly advantageous if the permanent magnet in the form of a ring is magnetized radially. In this case, one of the two magnetic poles is located in the region of the outer circumference and the other of the two magnetic poles is located in the region of the inner circumference of the annular permanent magnet.

It is considered particularly expedient for the permanent magnets to be embodied as a constituent part of the stator. Preferably, the armature is completely free of permanent-magnetic components. Since the permanent magnets belonging to the stator do not have to perform the stroke movement of the armature together, the armature can be operated with high switching dynamics and with a fast response time to the electrical actuation signal. Furthermore, the armature can be produced in one piece at a very low cost.

Expediently, a preferably annular permanent magnet belonging to the stator is arranged axially in a coaxial orientation between the two electromagnetic coils. Thereby, each of the two electromagnetic coils is between the permanent magnet and one of the two pole rings. The permanent magnet field of the permanent magnet consists of two partial magnetic fields which each pass through the armature body having the property of guiding the flux and which each further pass through one of the two pole rings having the property of guiding the flux.

Preferably, the yoke mechanism also comprises a flux-guiding yoke sleeve radially enclosing the two electromagnetic coils, the two pole rings and the permanent magnet on the outside, which yoke sleeve is in flux-guiding connection with the two pole rings and preferably also with the permanent magnet. The two aforementioned sub-magnetic fields are guided by the yoke sleeve between the permanent magnets and the respective pole ring in a region radially outside the electromagnetic coil.

Preferably, the armature is movable relative to the stator between two end-of-travel positions axially opposite each other. Advantageously, the armature is permanently prestressed into one of the two end-of-stroke positions by a spring mechanism acting between the stator and the armature. By means of such a spring pretensioning, a very simple monostable operating behavior of the armature can be achieved. In the case of proportional solenoid valves, a "normally closed" or "normally open" valve type can be realized in particular by means of an armature which is prestressed into the end-of-travel position by means of a spring mechanism.

When the drive mechanism is to be imparted with a bistable functionality of the armature, a spring mechanism is preferably also present.

Preferably, the spring means is associated with one of the two axial end regions of the armature and is thereby inserted axially between the armature and the component parts of the stator. The spring mechanism is suitably a pressure spring mechanism.

Expediently, the armature is supported radially with respect to the stator and is guided axially linearly displaceably. Preferably, there is no touch between the armature body and the stator. Suitably, the annular air gap extends radially between the armature body and the stator over the entire axial length of the armature body. Expediently, two guide pins of the armature, which are respectively present in addition to the armature body, each of which is assigned to one of the two axial end regions of the armature and which are each recessed in a radially supported manner in an axially displaceable manner in a guide recess formed at the stator, are responsible for the linear guidance with respect to the stator. The guide pins are made in particular of a material which does not act as a flux guide, so that they do not influence the permanent magnet field nor the coil magnetic field in any way. The guide pins are expediently separate structural parts from one another, but can also be formed by the two end sections of a one-piece guide body which passes through the armature body.

Preferably, the armature body has a cylindrical profile completely on the outside, which profile expediently does not have any graduation.

The guide pin is preferably likewise of cylindrical design at its radially outer circumference.

At least one of the two stator-side guide recesses is expediently formed by a central annular opening of the cylindrically designed contour of the two pole rings. In principle, each of the two pole rings can delimit one of the two guide notches. However, as a possible embodiment, it is preferred that one of the two pole rings does not assume a guiding role and instead the guide pin associated with the pole ring is inserted into a guide recess of the stator, which is delimited by other components of the stator, for example by an axial closing element, which preferably has no flux-guiding properties.

Each annular armature body end section is preferably of flange-shaped design at least when it has a conically tapering inner circumferential surface.

Preferably, each annular armature body end section surrounds an axially open end-side recess of the armature body, which recess has a planar, preferably circular, bottom face which extends in a plane at right angles to the main axis.

Preferably, the two guide pins extend at least over a partial length within an end-side recess of the armature body enclosed by the associated annular armature body end section. In this case, a radial annular gap can be present between each guide pin and the associated annular armature end section, which annular gap tapers in each case with an inner circumferential surface of the armature end section that tapers conically towards the axial interior.

Suitably, each guide peg projects axially from the armature body. Advantageously, at least the length section of the guide pin protruding from the end-side recess interacts with the guide recess of the stator for the purpose of linear guiding of the armature.

The description about the characteristic functioning as a guide flux is understood as a characteristic for guiding a magnetic flux. As long as the components of the electromagnetic drive are flux-conducting, their flux-conducting properties are preferably based on a design made of ferromagnetic material, in particular of soft-magnetic material. The components which do not serve for conducting the flux are made, for example, of a plastic material, an aluminum material or of an austenitic material.

Suitably, in the region of the free end of the armature body end section or at the axial height of the free end of the armature body end section, the circular surface enclosed by the conical inner circumferential surface is at least 75% and suitably in the range of 90% of the circular surface enclosing the outer circumference of the annular armature body end section.

In a preferred embodiment, the proportional solenoid valve comprising the electromagnetic drive is designed as a valve seat, wherein its valve ring segment is arranged on the front end side of the armature and is opposite the valve seat within a valve chamber delimited by the valve housing, said valve seat enclosing a passage opening into the interior of the first fluid passage in the valve chamber and the valve ring bearing against said valve seat in the closed position. A further, second fluid channel opens into the valve chamber, which further, second fluid channel communicates with the first fluid channel through the valve chamber when the valve ring is moved into the open position lifted from the valve seat by a corresponding actuation of the armature.

Expediently, the armature is axially traversed by a pressure compensation channel, which, at least in the closed position of the valve collar, establishes a fluid connection between the first fluid channel and a pressure compensation chamber bounded by the rear end face of the armature, wherein the cross section of the pressure compensation chamber is as large as the cross section of the inner channel opening of the first fluid channel. Thereby, the armature is pressure balanced so that the driving force that can be applied to it is independent of the fluid force of the fluid to be controlled.

The electromagnetic drive can be equipped with a sensor mechanism which allows the position of the armature to be detected. Such a sensor arrangement comprises, for example, a hall sensor arrangement which cooperates with a permanent-magnetic element, wherein the permanent-magnetic element is preferably designed as a magnetic ring.

Drawings

The invention is subsequently explained in more detail with the aid of the attached drawings. Wherein:

fig. 1 shows a first preferred embodiment of a proportional solenoid valve according to the invention in a partially disassembled state, wherein the solenoid valve is equipped with a preferred embodiment of an electromagnetic drive according to the invention,

fig. 2 shows a further, disassembled illustration of the assembly from fig. 1, wherein, unlike in fig. 1, not only the stator but also the armature is shown in longitudinal section in the drive mechanism,

fig. 3 shows a longitudinal section through the assembly from fig. 1 and 2 in the closed position of the valve collar, in which the armature occupies one of two possible end-of-stroke positions,

fig. 4 shows the same longitudinal section as in fig. 3, however in the open position of the valve ring, in which the armature assumes an intermediate stroke position, an

Fig. 5 again shows a longitudinal section corresponding to fig. 3 and 4, wherein the valve ring is shown in the maximum open position and the armature assumes the opposite end-of-travel position with respect to the operating state shown in fig. 3.

Detailed Description

In the drawing, a proportional solenoid valve 1 is illustrated, which is equipped with an electromagnetic drive 2, by means of which a valve element 3 of the solenoid valve 1 can be driven in a linear control movement 4, illustrated by a double arrow.

The drive mechanism 2 has an imaginary main axis 5, which exemplarily relates to a central longitudinal axis of the drive mechanism 1. The control movement 4 of the valve element 3 is carried out in the axial direction of the main axis 5.

The solenoid valve 1 has a valve housing 6. The valve housing 6 is exemplary of multi-part design and comprises a first housing part 7 and a second housing part 8 attached to the first housing part 7. Preferably, the second housing part 8 is detachably fixed to the first housing part 7 by means of a fixing means 11, in particular a fixing threaded fastener.

The second housing part 8 is preferably formed by the stator 12 of the drive mechanism 2. The drive mechanism 2 furthermore has an armature 13 which can be moved linearly back and forth relative to the stator 12 in the axial direction of the main axis 5, wherein the movement is referred to below as a stroke movement 14, which is illustrated by a double arrow.

The drive mechanism 2 has an externally accessible coupling element 15, which is formed as a component of the stator 12 and to which an actuating voltage can be applied, by means of which the drive mechanism 2 can be actuated to generate the stroke movement 14.

A deepening is formed in the first housing part 7, which is closed by the second housing part 8 attached, so that it forms a valve chamber 16 into which the armature 13 projects with a front end section 17. At the front end section 17, the already mentioned valve ring 3 is arranged on the end side, which valve ring exemplarily comprises a rubber-elastic sealing element, which is for example of disc-shaped or plate-shaped design.

The first housing part 7 is traversed by a first fluid channel 22, which opens out with a first outer coupling opening 22a toward the outer face of the first housing part 7 and furthermore with a first inner channel opening 22b into the valve chamber 16. The first inner channel opening 22b is opposite the valve ring 3 in the axial direction of the main axis 5 and is surrounded by an annular valve seat 24 facing the valve ring 3.

The second fluid channel 23, which likewise passes through the first housing part 7, opens with a second outer coupling opening 23a to the outer face of the first housing part 7 and also with a second inner channel opening 23b into the valve chamber 16 in such a way that, independently of the current position of the valve element 3, an open connection exists between the valve chamber 16 and the second outer coupling opening 23 a.

In a typical operating mode of the proportional solenoid valve 1, a fluid, for example compressed air, which is under excess pressure is fed into the first fluid channel 22 at the first outer coupling opening 22 a. As long as the valve element 3 rests against the valve seat 24 in the closed position, which can be seen in fig. 3, the first fluid channel 22 is separated from the valve chamber 16 and thus also from the second fluid channel 23, so that no fluid flow occurs. By corresponding actuation of the drive mechanism 2, the valve ring 3 can be driven into a control movement 4 in such a way that it assumes an open position lifted from the valve seat 24, wherein fig. 4 and 5 illustrate two possible open positions. In each open position, fluid introduced into the first fluid channel 22 can flow through the opened first inner channel opening 22b into the valve chamber 16 and from there through the second fluid channel 23 and the second outer coupling opening 23a out of the valve housing 6 to the coupled consumer.

It is understood that the solenoid valve 1 can also be operated in the opposite flow direction, wherein the fluid to be controlled is fed in at the second outer coupling opening 23 a.

The valve link position which can be occupied by the valve link 3 in the range of the control movement 4 shall also be referred to below as the control position. One of the control positions is a closed position, which can be seen in fig. 3. The further control position is an open position raised from the valve seat 24, wherein the valve ring 3 can be positioned steplessly in different open positions which differ from one another with respect to the distance from the valve seat 24. Fig. 5 shows the maximum open position with the maximum possible distance between the valve ring 3 and the valve seat 24. In fig. 4, an intermediate open position is shown, which is intermediate between the closed position and the maximum open position.

The stepless adjustability of the different opening positions enables openings of different sizes of flow cross sections, so that the solenoid valve 1 can be used for pressure regulation and/or flux regulation.

Since the valve element 3 is drivingly coupled to the armature 13, the control movement 4 of the valve element 3 is derived from the stroke movement 14 of the armature 13. When the valve ring 3 is fixedly seated on the armature 13, the control movement 4 directly corresponds to the stroke movement 14. This is the case in this embodiment.

According to a non-illustrated embodiment, the valve ring 3 is designed separately from the armature 13, but is nevertheless drivingly coupled to the armature 13 by suitable coupling means.

The armature 13 can be moved within the range of the stroke movement 14 between a first stroke end position, which can be seen in fig. 3, and a second stroke end position, which can be seen in fig. 5. The first end-of-travel position of the armature 13 corresponds to the closed position of the valve collar 13, and the second end-of-travel position corresponds to the maximum open position of the valve collar 3. The armature 13 can be positioned steplessly relative to the stator 12 between the two end-of-travel positions axially opposite each other.

A preferred structure of the electromagnetic drive mechanism 2 is described below.

The stator 12 of the drive mechanism 2 has a coil assembly 25 which is electrically coupled to the coupling element 15 and can be supplied with current by applying a control voltage to the coupling element 15. The coil arrangement 25 is arranged coaxially to the main axis 5 and has two electromagnetic coils 26, 27, which are coaxial to one another and are also referred to below as first electromagnetic coil 26 and second electromagnetic coil 27.

Preferably, the two electromagnetic coils 26, 27 are configured identically with regard to their size and their effective power.

The two electromagnetic coils 26, 27 each contain a coil winding made of an insulatively coated coil wire, wherein the two electromagnetic coils 26, 27 are wound in the same direction. Both of the electromagnetic coils are coupled to the coupling element 15, so that the application of the actuating voltage simultaneously causes a magnetic field, which is referred to as a coil magnetic field for better differentiation, in the two electromagnetic coils 26, 27.

Preferably, the two solenoids 26, 27 are connected in series so that they are traversed by the same operating current. However, the two electromagnetic coils can also be designed substantially separately from one another and can be actuated separately from one another. It is important that the coil magnetic field has a field direction 28, which is illustrated by an arrow in the drawing, and which is oriented axially opposite to one another in the region between the two electromagnetic coils 26, 27.

Each electromagnetic coil 26, 27 preferably has a winding

portion

26a, 27a made of coil wire and an annular coil carrier 26b, 27b, in particular made of plastic material, carrying the winding

portion

26a, 27 a.

Furthermore, an annular permanent magnet 32, which is arranged axially between the two electromagnetic coils 26, 27 in an orientation coaxial to the main axis 5, belongs to the stator 12. The permanent magnet 32 in combination with a further flux-guiding yoke 33 of the stator 12 causes a permanent-magnet pretensioning of the armature 13. The following characteristic is understood to act as a guiding flux, i.e. capable of guiding the magnetic field lines and thereby the magnetic flux.

The permanent magnet 32 can in principle also be embodied as a component of the armature 13, but has proven to be particularly advantageous when integrated into the stator 12, as is the case in this exemplary embodiment.

Preferably, the permanent magnets 32, which are configured as ring magnets, are radially magnetized. The internal field direction of the permanent magnet field 34 in the permanent magnet 32 is illustrated at 35 by an arrow.

Based on the subsequently described design of the yoke mechanism 33, the permanent magnet field 34 is composed of two sub-magnetic fields 34a, 34b, which extend around a respective one of the two electromagnetic coils 26, 27, respectively, comparable to the two coil magnetic fields. This means that the permanent magnet field 34 always runs in the same direction with respect to the magnetic field of one coil and in the opposite direction with respect to the magnetic field of the other coil. Which of the two coil magnetic fields is oriented in the same or opposite direction with respect to the permanent magnet field 34 depends on the direction of the current flow of the two electromagnetic coils 26, 27.

The yoke mechanism 33, which has already been mentioned as acting as a flux guide, is composed of a plurality of components, each having the property of acting as a flux guide. The flux-guiding properties are caused in particular by the fact that the components are made of ferromagnetic material, wherein in particular soft magnetic steel is used. Alternatively, the flux-guiding properties can also be brought about, for example, by ferromagnetic particles being embedded in a polymeric base material which does not guide the flux.

The yoke mechanism 33 has two pole rings 36, 37, which serve to guide the flux and are also referred to below for better distinction as a first pole ring 36 and a second pole ring 37. The two pole rings 36, 37 are integral parts of the stator 12 and are each arranged in a coaxial arrangement with respect to the main axis 5 on the outer side of one of the two electromagnetic coils 26, 27 axially opposite the respective other electromagnetic coil 27, 26. Each electromagnetic coil 26, 27 is thereby laterally surrounded at its axially inner side facing the other electromagnetic coil 27, 26 by the permanent magnet 32 and at the opposite axially outer side by one of the two pole rings 36, 37.

Preferably, the permanent magnet 32 and the two pole rings 36, 37 respectively bear directly axially against the associated electromagnetic coil 26, 27, in particular in an insulated manner against the associated coil carrier 26b, 27 b.

The yoke mechanism 33 expediently also has a flux-guiding yoke sleeve 38 which is arranged coaxially to the main axis 5 and has an axial length such that it encloses both the permanent magnet 32 and the two electromagnetic coils 26, 27 and the two pole rings 36, 37 radially on the outside. The yoke sleeve is preferably of hollow cylindrical design.

The yoke sleeve 38 is in flux-guiding connection with the two pole rings 36, 37. For this purpose, the two pole rings 36, 37 have, as an example, an outer diameter which corresponds to the inner diameter of the yoke sleeve 38, so that there is direct touching contact. Additionally or alternatively, the components can also be pressed into each other or bonded to each other.

Preferably, the permanent magnet 32 is also in flux directing connection with the yoke sleeve 38. For this purpose, the permanent magnet 32 preferably has an outer diameter which corresponds to the inner diameter of the yoke sleeve 38, so that the two parts bear radially against one another. The permanent magnet 32 can be pressed or glued in, for example, in accordance with the given conditions in the case of the two pole rings 36, 37.

In the drawing, an axial groove in the outer circumference of the permanent magnet 32, through which the coil wire connecting the two electromagnetic coils 26, 27 is guided, can be seen at 42 in fig. 4.

The length section of the inner circumference of the yoke sleeve 38 which extends axially beyond the two electromagnetic coils 26, 27 and the permanent magnet 32 expediently has a smaller diameter than the two

outer end sections

43, 44 of the yoke sleeve 38 which are axially connected thereto, so that in each case an axial stop shoulder 45 is obtained, against which one of the two pole rings 36, 37 with a correspondingly larger outer diameter respectively bears axially.

The drive mechanism 2 is preferably fastened to the valve housing 6 in such a way that it is pushed with the front outer end section 43 of the yoke sleeve 38 associated with the front end section 17 of the armature 13 onto an annular fastening projection of the first housing part 7 enclosing the valve chamber 16. The sealing ring 47 located therebetween ensures a fluid-tight seal.

At a rear side 48 of the drive mechanism 2, which is opposite the front end section 17 of the armature 13 in the axial direction of the main axis 5, the yoke sleeve 38 is axially plugged with the rear outer end section 44 onto a particularly cover-shaped closing element 52 of the stator 12. The closure element 52 is preferably made of a material that does not function to guide flux. Exemplarily, the closing element 52 is axially supported with an annular shoulder 53 at the yoke sleeve 38 and is fastened with the yoke sleeve 38 and the first housing part 7 by means of a fastening element. The sealing ring 49 is also expediently situated between the closing element 52 and the yoke sleeve 38.

The yoke mechanism 33, together with the annular permanent magnet 32 and the two electromagnetic coils 26, 27, encloses an armature receiving space 54 coaxial with the main axis 5, in which the armature 13 extends axially. The armature 13 has a central longitudinal axis 19, which exemplarily overlaps the main axis 5.

The armature 13 has an armature body 55, which serves for guiding the flux, with a radially outwardly directed outer circumferential surface 56, which is expediently of cylindrical design. The outer diameter of the armature body 55 is at a minimum smaller than the inner diameter of the yoke mechanism 33 and the permanent magnet 32 and the two electromagnetic coils 26, 27, so that the armature body is enclosed by the stator 12 with a slight annular air gap remaining.

In the region of the front end section 17, the armature 13 has a guide pin 62 which projects axially beyond the front of the armature body 55 which serves as a guide flux. A further, rear guide pin 63 is located at the rear end section 57 of the armature 13 axially opposite the front end section 17 and projects beyond the armature body 55 on the rear side. By means of the two guide pins 62, 63, the armature 13 is guided so as to be linearly displaceable for carrying out the stroke movement 14, while the stator 12 is supported in the radial direction.

Each

guide pin

62, 63 is inserted with a

guide section

62a, 63a, which has a radially outwardly directed

cylindrical guide surface

62b, 63b at its outer circumference, into a front or

rear guide recess

58, 59 formed by the stator 12. The two guide recesses 58, 59 have an inner diameter matched to the outer diameter of the associated

guide section

62a, 63a, so that the guide surfaces 62b, 63b bear axially displaceably against them and each

guide pin

62, 63 can slide in the associated front or

rear guide recess

58, 59 during the stroke movement 14.

The rear guide recess 59 is preferably designed as an axial deepening in the closing element 52. The front guide recess 58 can in principle likewise be formed by parts of the stator 12 which do not belong to the yoke mechanism 33, but preferably by a central annular opening 36a of the cylindrical design contour of the first pole ring 36. This allows the stator 12 to be realized with a short overall length.

The two guide pins 62, 63 are expediently made of a material which does not contribute to the flux guidance for the magnetic flux. The two guide pins are made, for example, of a plastic material or of a stainless steel material.

During the stroke movement 14, the guide pins 62, 63 slide with radial support in the axial direction in the respectively associated guide recesses 58, 59.

Preferably, the two guide pins 62, 63 are constructed separately from one another and are fixed independently of one another at the armature body 55. This is the case in the illustrated embodiment. Each

guide pin

62, 63 has a pin-shaped fastening lug 64 on the rear side, by means of which it is inserted into a through-hole 65 which passes centrally through the armature body 55. Suitably, each fixing lug 64 has an external thread, by means of which it is screwed into an internal thread of the through hole 65.

The two guide pins 62, 63 are inserted into the through-opening 65 from the end sides opposite to each other.

According to an embodiment that is not illustrated, the two guide pins 62, 63 pass through an integral component of a one-piece guide body that passes through the through-opening 65.

Suitably, each

guide peg

62, 63 has a head section 66 axially coupled to the fixing projection 64. The end section of the head section 66 axially opposite the fastening projection 64 forms the associated

guide section

62a, 63 a. The head section 66 has a larger diameter than the fastening lug 64 and is supported at an opposite end face 68 of the armature body 55 with an annular rear end face 67 surrounding the fastening lug 64.

The armature body 55 has two end sections which are opposite one another in the longitudinal direction 19 of the armature 13 and which shall be referred to as armature

body end sections

72, 73. For better differentiation, in the following, the armature body end section 72 associated with the front end section 17 is also referred to as first armature body end section 72, while the armature body end section 73 associated with the rear end section 57 of the armature 13 is also referred to as second armature body end section 73.

The two

armature end sections

72, 73 have cylindrical outer peripheral surfaces 74. The outer circumferential surface is correspondingly formed by a length section extending over the entire outer circumferential surface 56 of the armature body 55 at the radial outer circumference.

The armature body 55 has an axial length which is greater than the clear distance between the two pole rings 36, 37, i.e. the clear distance between the axially inner distances of the two pole rings 36, 37, measured between the two axially end faces 75 of the two pole rings 36, 37 facing toward one another. On the other hand, the armature body 55 is shorter than the distance measured between the two outer axial end faces of the two pole rings 36, 37 facing away from each other. Furthermore, by mechanical interaction with the stator 12, it is ensured that the armature body 55 is immersed with the two

armature end sections

72, 73 into the adjacent first or

second pole ring

36, 37 in each stroke position that can be set during operation of the drive mechanism 2. However, the penetration depth is always smaller than the axial length of the

respective pole ring

36, 37 measured between the inner axial end face 75 and the outer axial end face 76. In each stroke position, the two armature

body end sections

72, 73 are thus present with only partially axial covering of the respectively adjacent first or

second pole ring

36, 37.

In each stroke position of the armature 13, that is to say not only in the two stroke end positions but also in each stroke position lying therebetween, a radial annular gap 77 is present between each armature

body end section

72, 73 and the

pole ring

36, 37 which surrounds it, the axial length of which corresponds to the axial cover length between the armature body 55 and the

respective pole ring

36, 37 and which is smaller than the axial length of the

respective pole ring

36, 37.

Preferably, each armature

body end section

72, 73 is radially outwardly enclosed by the

pole ring

36, 37 associated therewith, wherein an associated radial annular gap 77 is located between the cylindrical outer circumferential surface 74 of the armature

body end section

72, 73 and a radial inner circumferential surface 78 of the

pole ring

36, 37.

During the stroke movement 14, the axial cover length of the two

armature end sections

72, 73 changes. The axial cover length with respect to one

polar ring

36 or 37 becomes correspondingly larger, while the axial cover length with respect to the other

polar ring

37, 36 becomes smaller. Correspondingly, the axial annular gap length of the two radial annular gaps 77 also changes.

Each radial annular gap 77 delimits, over the axial length, an annular air gap radially between the outer circumferential surface 74 of the armature

body end section

72, 73 and the radially inner circumferential surface 78 of the associated

pole ring

36, 37.

Preferably, the length dimensions are matched to one another in such a way that in the intermediate stroke position of the armature 13, which is illustrated in fig. 4, in which the two armature

body end sections

72, 73 are immersed with the same axial cover length into the respectively

adjacent pole ring

36, 37, the axial cover length corresponds to 0.3 to 1.5 times the maximum armature stroke, wherein the maximum armature stroke is the armature stroke that the armature 13 can travel between its two stroke end positions.

In the illustrated exemplary embodiment, a final stroke position of the armature 13 is defined in that the valve element 3 rests against the opposite valve seat 24 in the closed position. This is illustrated in fig. 3. The other end-of-travel position (which in the illustrated exemplary embodiment corresponds to the maximum open position of the valve ring 3 and which is illustrated in fig. 5) is preset, for example, in such a way that the armature 13 comes to rest against a component of the stator 12, for example against the closure element 52.

A further feature of the drive mechanism 2 is that the two armature

body end sections

72, 73 of the armature body 55 are of annular design and accordingly have an inner circumferential surface 79 which tapers conically from the axially outer side to the axially inner side. This is manifested in that the annular armature

body end sections

72, 73 taper towards their axially oriented free ends 71. That is to say, the thickness of the annular cross section of the armature end section at right angles to the main axis 5, measured in the direction radial to the main axis 5, becomes continuously smaller towards the free end 71 of the

armature end section

72, 73.

In order to obtain such a contour of the armature

body end sections

72, 73, an axial deepening 82, which tapers axially inwardly, is expediently introduced into the armature body 55 from each axial end side, wherein its radial limiting surfaces form the conical inner circumferential surface 79 of the armature

body end sections

72, 73.

Preferably and in accordance with the exemplary embodiment illustrated, the conical inner circumferential surface 79 extends from the free end 71 at the end over the entire length of the axial deepening 82.

Alternatively, however, the conical inner circumferential surface 79 can also be shorter and end before the axially inner end of the axial deepening 82, wherein then the cylindrical inner circumferential surface of the annular armature

body end sections

72, 73 is expediently coupled axially inside to the conical inner circumferential surface 79. The transition between the conical inner circumferential surface 79 and the cylindrical inner circumferential surface is expediently formed here by an annular edge.

The axial deepening 82 is expediently bounded axially on the inside by the axially outwardly directed bottom surface 68 a. The bottom surface 68a is expediently of circular contour and preferably extends in a plane at right angles to the longitudinal axis 19. The bottom surface 68a is a surface section of the end surface 68 that is axially deeper in the armature body 55 than the free end 71.

Preferably, at the level of the free end 71 of the armature

body end section

72, 73, the circular opening surrounded by the conical inner circumferential surface 79 occupies at least 75% of the circular surface which encloses the outer circumference of the annular armature

body end section

72, 73. Preferably, the area fraction is in the range of 90% and preferably just 90%.

The internal taper of the

armature end sections

72, 73 advantageously effects calibration of the axial stroke position of the armature 13. A very well proportional movement behavior is obtained by a large range of actuating voltages which can be applied to the coil arrangement 25 at variable magnitudes.

This is due in particular to the fact that the strong magnetic field which is in contact in the region of the

armature end sections

72, 73 is impeded in terms of unrestricted passage by the reduced annular cross section of the armature end sections, so that a leakage field is formed which, despite the radial air gap, exerts an axial magnetic drive force on the armature body 55. When the armature 13 then moves together with the armature element 52, although the flux cross section of the armature

body end sections

72, 73 for the magnetic field, which is further referred to above as the annular cross section, changes, this however hardly influences the drive force, since the magnetic flux also changes at the same time, so that the leakage field responsible for the axial drive force is always present. In particular, in the vicinity of the end stroke position, i.e. in the edge region of the stroke position to be set, the force/stroke characteristic curve is thus provided, which has good linearity and positively influences the regulating behavior.

In each operating state of the drive mechanism 2, the two radial annular gaps 77 are traversed by the permanent magnet field 34 or by one of the sub-magnetic fields 34a, 34 b. The passage of current through the coil assembly 25 results in the generation of two coil magnetic fields which are superimposed on the two sub-magnetic fields 34a, 34b of the permanent magnet 32. Depending on the direction of the current flow of the coil arrangement 25, a strengthening of the partial magnetic fields 34a, 34b results in the region of the respective one radial annular gap 77 and a weakening of the partial magnetic fields 34a, 34b results in the region of the respective other radial annular gap 77, so that overall a stronger axial magnetic force action occurs in the region of the respective one

armature end section

72, 73, while the magnetic force action is weakened in the region of the other

armature end section

72, 73. The absolute intensity can be varied with respect to the magnitude of the applied actuating voltage or the resulting current intensity.

For the operating behavior of the drive mechanism 2, it is advantageous if a spring mechanism 83 is present, which acts between the stator 12 and the armature 13 and by means of which the armature 13 is permanently biased into one of its two end-of-stroke positions relative to the stator 12. The illustrated exemplary embodiment is equipped with a spring mechanism 83 which is here, by way of example, configured and arranged in such a way that the armature 13 is elastically biased into an end-of-travel position corresponding to the closed position of the valve ring 3.

The spring mechanism 83 is in particular a pressure spring mechanism.

The spring mechanism 83 is arranged in the interior of the stator 12, for example axially between the rear end section 57 of the armature 13 and the closing element 52. The spring mechanism is axially supported at the two

aforementioned components

57, 52, respectively. For example, the spring mechanism comprises a coil spring.

The spring mechanism 83 interacts with the rear guide pin 63 in the armature 13. The rear guide pin 63 has a blind-hole-like recess 84 extending in the head section 66, into which the spring mechanism 83 is braced against lateral bending. The spring force FF exerted on the armature 13 by the spring mechanism 83 is illustrated by an arrow.

Fig. 3 to 5 show exemplary different possible stroke positions of the armature 13 and, corresponding thereto, also different control positions of the valve ring 3 connected to the armature 13.

Fig. 3 shows the end-of-travel position of the armature 13, in which the valve element 3 assumes the closed position. The coil arrangement 25 is energized in such a way that a significantly stronger resulting magnetic field is present in the region of the radial annular gap 77 associated with the first armature end section 72 than in the region of the rear second armature end section 73. As a result, the valve collar 3 is pressed against the valve seat 24.

Fig. 5 shows an operating state in which the resultant magnetic field is significantly greater in the region of the radial annular gap 77 associated with the second armature end section 73 than in the region of the first armature end section 72. As a result, the armature 13 is displaced in the direction of the second pole ring 73, so that it assumes a further end-of-travel position, which corresponds to the maximum open position of the valve ring segment 3.

In the end-of-stroke position, which can be seen from fig. 3, the axial cover length has a maximum in the region of the first armature end section 72 and a minimum in the region of the second armature end section. In the second end-of-stroke position, which can be seen from fig. 5, the states are exactly opposite.

Fig. 4 shows an intermediate stroke position of the armature 13, in which the cover length is equally large at the two armature

body end sections

72, 73. In this case, the actuating voltage applied to the coil arrangement 25 is reduced compared to the end-of-travel position, which defines the maximum open position of the valve element 3, so that the set open position is an intermediate open position, the flow cross section of which is smaller than in the maximum open position.

In the illustrated embodiment, the two

armature end sections

72, 73 are designed annularly and have an inner circumferential surface 79 which tapers conically toward the axial interior, whereas in the non-illustrated embodiment only one of the two armature end sections is designed in the manner described. That is, the inner cone can be arranged not only on one side but also on both sides. The armature cones on both sides realize the adjusting force in the case of bistable functionality in the two axial directions. If only a single stable functionality is desired, which works for example by means of a spring return, a single-sided armature body cone is sufficient. In this case, the opposing armature body end sections can be of cylindrical design, for example. The explanations with respect to the axial cover of the associated pole ring are also applicable to such a design.

Preferably, the cone angle 80 (which can be identified in fig. 5 by the double arrow), which can also be referred to as the opening angle, of the conically tapering inner circumferential surface 79 lies in a range between 20 ° and 120 °. Cone angles in the range between 40 ° and 80 ° have proven to be particularly suitable. Range boundaries are included in the two range data, respectively.

In the illustrated embodiment, the annular armature

body end sections

72, 73 are flattened at their free ends 71 on the end sides. Nevertheless, the annular end face has only a small radial dimension. In accordance with a non-illustrated embodiment, the free end 71 can also end sharply with axially oriented edges or be rounded.

In accordance with the exemplary embodiment illustrated, the two guide pins 62, 63 can extend at least over a partial length within the respective end-side recess or recess 55 of the armature body 55. The end face 68 of the armature body 55 is formed, by way of example, by an axially outwardly oriented base face 68a of the end-side recess 82, at which the guide pins 62, 63 bear against the armature body 55.

Expediently, an annular radial air gap 85 extends between each

guide pin

62, 63 and the conical inner circumferential surface 79 of the associated armature

body end section

72, 73.

Each

guide pin

62, 63 projects with its head section 66 axially out of the associated end-side recess 82, wherein at least the length section outside the end-side recess 82 forms the

guide section

62a, 63 a.

The proportional solenoid valve 1 is expediently equipped with a pressure compensation means, which ensures that, at least in the closed position and preferably also in the open position, no resultant axial fluid pressure acts on the armature 13.

The pressure compensation measure provides that the armature 13 is passed through axially in the middle by a pressure compensation channel 86, which opens with a front channel opening 87 at a closing surface 88 of the end face of the valve ring 3 facing away from the armature 13 and which opens with an axially opposite rear channel opening 89 into a pressure compensation chamber 92 located inside the stator 12. The pressure compensation chamber 92 is coupled to the rear end section 57 of the armature 13 axially opposite the valve ring 3 and is limited by the rear guide pin 63 and the closing element 52. A sealing ring 93, which is fixed radially on the outside in the head section 66 of the rear guide pin 63, ensures that the pressure compensation chamber 92 is separated from the armature receiving space 54 in a fluid-tight manner.

Preferably, the spring mechanism 83 is disposed in the pressure equalizing chamber 92.

Suitably, the pressure equalisation channel 86 extends axially through the valve member 3, the armature body 55 and the two guide pegs 62.

The cross section of the pressure compensation chamber 92 is as large as the cross section of the first inner channel opening 22b, which is covered by its end-side closing surface 88 in the closed position of the valve ring 3.

In the closed position of the valve ring 3, the first fluid channel 22 communicates with the pressure compensation chamber 92 through the front channel opening 87 and the pressure compensation channel 86, so that the same pressure prevails in the latter as in the first fluid channel 22. As a result, the armature 13 is loaded with equally large fluid pressures in the two axial directions, which cancel each other out (egalisieren). The same effect occurs when the valve element 3 assumes the open position, since then the same pressure prevails in the pressure compensation chamber 92 as in the region of the front passage opening 87 of the valve chamber 16.

The drive mechanism 2 can be equipped with a stroke sensing mechanism for the armature 13. Furthermore, the proportional solenoid valve 1 can be equipped with a pressure sensor and/or a flux sensor.

Claims

1. An electromagnetic drive having a stator (12) which has a current-carrying coil arrangement (25) with two electromagnetic coils (26, 27) arranged coaxially to the main axis (5) and spaced apart from one another and a flux-carrying yoke arrangement (33) with two flux-carrying pole rings (36, 37) which laterally surround one of the two electromagnetic coils (26, 27) in a coaxial orientation on the outside axially facing away from the other electromagnetic coil (26, 27), and having an armature (13) which is coaxially surrounded by the coil arrangement (25) and which has a flux-carrying armature body (55) which is passed through by the permanent magnet field (34) of the permanent magnet (32) of the drive (1) as continuously as the yoke arrangement (33) of the stator (12), the armature body has two axially opposite armature body end sections (72, 73) which are arranged adjacent to one of the two pole rings (26, 27) and each have a cylindrical outer circumferential surface (74), wherein the armature (13) can be moved back and forth axially relative to the stator (12) when a stroke movement (14) is carried out and can be positioned in different stroke positions as a result of the interaction of the permanent magnet field (34) with a coil magnetic field which can be caused by a controlled current flow of the coil arrangement (25), characterized in that the armature body (55) in each stroke position of the armature (13) with its two armature body end sections (72, 73) is immersed with only partially axial covering into the respectively adjacent pole ring (36, 37) so that in each armature body end section (72, 73), 73) A radial annular gap (77) is present between the adjacent pole rings (36, 37), wherein the axial cover length and thus the axial annular gap length is dependent on the stroke position of the armature (13), wherein at least one of the two armature body end sections (72, 73) is designed annularly and has an inner circumferential surface (79) which tapers conically from its free end (71) to the axial interior, so that the radial thickness of the annular cross section of the armature body end section (72, 73) at right angles to the main axis (5) decreases continuously toward its free end (71).

2. The electromagnetic drive according to claim 1, characterized in that the two armature body end sections (72, 73) are designed annularly and have an inner circumferential surface (79) which tapers conically from their respective free end (71) to the axial interior.

3. An electromagnetic drive according to claim 2, characterized in that in an intermediate stroke position of the armature (13), in which the axial cover length corresponds to 0.3 to 1.5 times the maximum possible stroke of the armature (13) during its stroke movement (14), the two armature body end sections (72, 73) sink into the respectively adjacent pole ring (36, 37) with the same axial cover length.

4. An electromagnetic drive mechanism according to any one of claims 1 to 3, characterized in that the conical angle (80) of the conical inner peripheral surface (79) of the armature body end section (72, 73) is in the range between 20 ° and 120 °, wherein the conical angle is suitably in the range between 40 ° and 80 °, respectively inclusive of the range boundaries.

5. An electromagnetic drive according to any one of claims 1 to 4, characterized in that the armature body end sections (72, 73) are flattened or provided with axially oriented edges or rounded at their end sides at their free ends (71).

6. An electromagnetic drive mechanism according to any one of claims 1 to 5, characterized in that the permanent magnet (32) is annularly configured and arranged coaxially to the main axis (5).

7. An electromagnetic drive mechanism according to claim 6, characterized in that the annular permanent magnet (32) is magnetized radially.

8. An electromagnetic drive mechanism according to any one of claims 1 to 7, characterized in that the permanent magnet (32) is an integral part of the stator (12).

9. Electromagnetic drive mechanism according to claim 8 in combination with claim 6 or 7, characterized in that the permanent magnet (32) is arranged axially in a coaxial orientation between the two electromagnetic coils (26, 27).

10. An electromagnetic drive according to any one of claims 1 to 9, characterized in that the yoke mechanism (33) has a flux-guiding yoke sleeve (38) radially outwardly enclosing the two electromagnetic coils (26, 27), the two pole rings (36, 37) and the permanent magnet (32), which yoke sleeve is in flux-guiding connection with the two pole rings (36, 37) and suitably also with the permanent magnet (32).

11. An electromagnetic drive mechanism according to any one of claims 1 to 10, characterized in that the armature (13) is movable relative to the stator (12) between two end-of-stroke positions axially opposite to each other, wherein the armature (13) is continuously pretensioned into one of the two end-of-stroke positions by a spring mechanism (83) acting between the stator (12) and the armature (13).

12. An electromagnetic drive according to any one of claims 1 to 11, characterized in that the armature (13) has guide pins (62, 63) at its two axial end regions, respectively, which are axially displaceably sunk in a radially supported manner into guide recesses (58, 59) formed at the stator (12), wherein the guide pins (62, 63) are expediently made of a material which does not contribute to guiding flux.

13. The electromagnetic drive according to claim 12, characterized in that at least one of the two guide recesses (58, 59) is formed by a central annular opening of a cylindrically designed contour of one of the pole rings (36, 37).

14. Electromagnetic drive according to claim 12 or 13, characterized in that the two guide pegs (62, 63) extend at least for part of their length within an end-side recess (82) of the armature body (55) enclosed by an associated annular armature body end section (72, 73), wherein an annular radial air gap (85) is expediently present between each guide peg (62, 63) and the associated armature body end section (72, 73) and/or each guide peg (62, 63) protrudes axially from the armature body (55).

15. Electromagnetic drive according to one of claims 1 to 14, characterized in that the flux-guiding properties are obtained by designing the relevant structural components from ferromagnetic, in particular soft-magnetic, materials.

16. An electromagnetic drive mechanism according to any one of claims 1 to 15, characterized in that the two electromagnetic coils (26, 27) are electrically connected in series and wound in the same direction.

17. An electromagnetic drive mechanism according to any one of claims 1 to 16, characterized in that in the region of the free end (71) of the armature body end section (72, 73), the circular face enclosed by the conical inner circumferential face (79) is at least 75% and suitably 90% of the circular face enclosing the outer circumference of the annular armature body end section (72, 73).

18. Proportional solenoid valve, which is designed for controlling a flow of a fluid, having a valve housing (6), a valve member (3) which can be moved relative to the valve housing (6) when a control movement (4) is carried out, and having an electromagnetic drive (2) for generating the control movement (4) of the valve member (3), characterized in that the electromagnetic drive (2) is designed according to one of claims 1 to 17, wherein the valve member (3) is drivingly coupled to the armature (13) for generating the control movement (4) thereof.

19. Proportional solenoid valve according to claim 18, characterized in that it is configured as a valve seat, wherein the valve ring (3) is arranged at a front end side of the armature (13) and is opposite a valve seat (24) within a valve chamber (16) limited by the valve housing (6), which valve seat surrounds a passage opening (22 b) of the interior of a first fluid passage (22) opening into the valve chamber (16) and against which the valve ring (3) rests in a closed position, wherein the armature (13) is axially traversed by a pressure equalization channel (86) which, at least in the closed position of the valve ring (3), establishes a fluid connection between the first fluid passage (22) and a pressure equalization chamber limited by a rear end side of the armature (13), wherein, the cross section of the pressure compensation chamber (92) is as large as the cross section of the channel opening (22 b) in the interior of the first fluid channel (22).