DE29509980U1 - Control device for a multi-way valve - Google Patents

Description

G 17 057 - lens 29 May 1995

Festo KG, 73734 Esslingen Control device for a multi-way valve

The invention relates to a control device for a multi-way valve, with a housing having a vertical direction, which is suitable for accommodating two electromagnets arranged next to one another, which each have a coil, wherein the coils are arranged with parallel axes in such a way that they lie one above the other with sections of their outer jacket surfaces facing one another in the housing vertical direction, and wherein each coil is assigned a valve member to be actuated, adjustable in the coil longitudinal direction, which works together with a valve seat, and with a manual actuation device which has an actuating slide for each valve member for its manual actuation, which extends downwards in the housing vertical direction from an actuating part located in the area of the top of the housing with a slide part guided longitudinally displaceably on the housing in the housing vertical direction and has an actuating part arranged in the area of the assigned valve member, which when actuated in the housing vertical direction

the actuating slide acts on the associated valve member, whereby at least the first actuating slide provided for actuating the lower valve member associated with the lower coil runs laterally past the upper valve member.

A control device of this type is described in DE 43 09 695 A1. This comprises a double magnet arrangement in which the two electromagnets lying one above the other are arranged slightly offset from one another, so that the actuating slide which interacts with the lower valve member can be easily guided past the upper valve member.

The known control device has proven itself in conjunction with relatively wide multi-way valves. However, when equipping particularly narrow valves, for example valves with a width of only 10 mm, the limits of miniaturization are reached. A further reduction in the width of the control device would necessarily make it necessary to guide the actuating slide protruding to the lower valve element through the receiving chamber of the upper valve element. A corresponding arrangement has already been proposed in JP 4-25081U, but has the disadvantage that additional sealing measures are required in the penetration area of the upper valve element chamber.

It is therefore the object of the present invention to provide a control device of the type mentioned above which

enables compact width dimensions without causing sealing problems.

To achieve this object, the invention provides that at least one actuating slide has an actuating arm that carries the associated actuating part and is elastically bendably connected to the guided slide part via at least one bending zone that enables transverse movement with respect to the housing, and that the actuating arm has an angled course towards its actuating part, wherein the angled area is higher than the longitudinal axis of the associated valve member and the freely ending first arm section adjoining the angled area and provided with the actuating part runs obliquely inwards and at the same time downwards in the direction of the associated valve member and cooperates with an inclined guide fixed to the housing.

In this way, it is possible to arrange the coils of the electromagnets in a common plane without being offset and at the same time to reach the lower valve member with an actuating slide that is actuated from above, without having to pass through the upper valve member chamber. The first actuating slide that works together with the lower valve member can initially run past the side of the upper valve member and then reach the lower valve member with the arm section of the actuating arm that is angled or bent inwards. The spring-elastic suspension of the actuating arm via the bending zone ensures that the freely ending arm section that has the actuating section has sufficient flexibility.

in order to engage with the associated valve member when the actuating section and the slide section arranged on it are displaced. The inclined guide supports the corresponding movement of the arm section in question. The actuating slide can be designed cost-effectively as a one-piece plastic component.

The actuating slide that interacts with the upper valve member can be constructed according to the same principles in order to obtain a uniform design. However, while the bending zone in the first actuating slide is expediently arranged above the associated lower valve member, in the case of the second actuating slide it is preferably located below the associated upper valve member, so that the spring-elastic bendable actuating arm does not protrude downwards from the bending zone as in the first actuating slide, but rather upwards.

As a further measure that enables compact dimensions, DE 43 09 695 A1 describes an advantageous design of a yoke device assigned to the coils. This yoke device is located in the immediate vicinity of the coils, but is characterized by the fact that, with the exception of a central yoke part, no other components of the yoke device are present in the area surrounding the cylindrical surface areas of the coils.

However, even based on this design principle, one reaches the limits of miniaturization. The

The control device is attached to the valve housing of a multi-way valve using fastening screws, so that sufficient space must be provided in the housing of the control device for the passage of these fastening screws.

This problem can be advantageously avoided if the yoke part assigned to both coils and the existing fastening screws are designed as a unit with a double function. The yoke part in question is therefore formed by at least one fastening screw of the control device, which can thus be accommodated in the installation space required anyway for the yoke part, so that no further space is required for fastening screws.

It is advisable to have only one central fastening screw, which preferably runs in a common plane with the coil longitudinal axes.

This makes it possible to create a control device that, thanks to the special design of the manual control device and the yoke device, enables very compact external dimensions. It goes without saying, however, that the manual control device and the yoke device can also be created independently of one another.

The invention is explained in more detail below with reference to the accompanying drawings. They show in detail:

Figure 1 shows a first design of the control device according to the invention in longitudinal section along section line I-I from Figure 2 in the state installed on a multi-way valve,

Figure 2 shows the control device from Figure 1 in cross section along section line II-II,

Figure 3 shows the control device from Figure 1 in cross section according to section line III-III from Figure 1,

Figure 4 is a side view of the control device, limited to the housing part containing the manual control device, looking in accordance with arrow IV in Figure 3,

Figure 5 shows the housing part containing the manual operating device in side view from the opposite side looking in accordance with arrow V, and

Figure 6 is a plan view of the housing part containing the manual operating device, looking "according to arrow VI in Figure 3.

Figure 1 shows a front end section of the valve housing 1 of a multi-way valve, for example a 5/3-way valve. The control device 3 is attached to the front surface 2 of the valve housing 1 and is releasably secured to it using a fastening screw 9. The multi-way valve contains

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a valve slide 4, only indicated schematically, which can assume various switching positions in which it establishes or interrupts fluidic connections between a pressure medium supply, one or more consumers and one or more vent openings. The switching takes place pneumatically by applying pressure to one or more actuating surfaces 5 assigned to the valve slide 4. The supply of the corresponding actuating fluid is controlled via the control device 3 described in detail below. The multi-way valve is expediently installed on a distributor plate during operation, which has internal pressure medium channels that communicate with valve channels formed in the valve housing 1.

The control device 3 comprises a housing 10 composed of several housing parts 10', 10", 10"' placed one after the other in axial succession. It contains two electrically actuated solenoid valves 6, 6' that function as control valves. Each of them has a rod-like valve member ₁₁ that can cooperate with a valve seat 8 provided in the first housing part 10' adjoining the valve housing 1, which is only indicated by a dot-dash line. By selectively actuating the solenoid valves 6, 6', the valve seats can be opened or closed as required in order to influence the flow of the actuating fluid to the actuating surfaces of the valve slide 4 and thereby move the valve slide 4 into the desired position.

The two solenoid valves 6, 6 ^' are arranged next to one another in the transverse direction at right angles to the longitudinal axis 12 of the control device 3 and the multi-way valve 1. The longitudinal axes 13 of the valve members 7 run parallel to the aforementioned longitudinal axis 12, the valve members 7 being axially movable in the direction of their longitudinal axes 13 when the associated solenoid valve 6, 6' is actuated.

According to Figure 2, the housing 10 has a rectangular contour on the outside, with the longitudinal axis of the rectangular cross-section defining the height direction 14 of the housing 10. Each solenoid valve 6, 6' has an electromagnet 15, 15' for its actuation, which contains a coil 16. The coils 16 are connected via electrical conductors (not shown in detail) to an electrical connection device 17, to which further signal conductors can be connected, which provide the necessary actuation signals for the electromagnets 15, 15'.

The two coils 16 are arranged next to each other with coil axes 18, 18' parallel to each other at the same axial height, whereby they are aligned parallel to the longitudinal axis 12 of the housing 10 of the control device 3. As Figure 2 shows, they lie one above the other in the housing height direction 14, with sections

22 of their outer cylindrical surface face each other. The coils 16 are spaced apart from each other so that between the two sections 22 there is a gap or intermediate area

23 is present.

Each coil 16 has a central, axially continuous through-opening 24 into which the associated valve member 7 extends a little way from the end face facing the valve housing 1. A magnetic core 25 is axially located opposite the inner end part of a respective valve member 7 and extends into the through-opening 24 from the end face opposite the valve housing 1.

A spring return element 26 arranged in a respective valve member 7 works together with the associated magnetic core 25 and presses the valve member 7 into the closed position against the associated valve seat 8 when the coils 16 are not excited. If current flows through a coil, a magnetic field is formed, the magnetic force of which draws the associated valve member 7 towards the associated magnetic core 25 and thereby switches to the open position, in which it is lifted off the associated valve seat 8.

The two coils 16 are arranged in such a way that the plane 27 containing their coil axes coincides with the vertical direction 14. This allows extremely small width dimensions of the housing 10 transverse to the said plane 27 to be achieved.

The coils 16 are housed in the middle housing part 10". The valve seats 8 are located in the front housing part 10' arranged between the middle housing part 10" and the valve housing 1, namely at the bottom of a valve member chamber 28, 28' open to the middle housing part 10", in

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into which the associated valve member 7 (indicated by dash-dotted lines in Figure 3) projects.

The front housing part 10' of the housing 10 is equipped with a manual actuation device 32, which makes it possible to manually lift the valve members 7 from the associated valve seat if necessary.

The rear housing part 10"', which adjoins the middle housing part 10" at the back, is in this case designed like a hood and contains a circuit board 33 that establishes the electrical connection between the coils 16 and the connection device 17. It is expediently made of transparent material in order to enable a favorable optical operating display while at the same time providing waterproof shielding of the circuit board 33 equipped with display elements.

In order to achieve a high switching force, in addition to the magnetic cores 25, a yoke device 34 is provided outside the coils 16. It consists in particular of iron and reduces the magnetic resistance for the magnetic field or its field lines outside the coils 16.

The yoke device 34 includes two plate-shaped yoke sections 35, which are arranged in front of the two front sides of the coils 16 with plate planes aligned at right angles to the coil axes 18, 18'. The front yoke section 35 has openings that allow the valve elements 7 to pass through. The rear

The yoke section 35 on the side has openings into which the magnetic cores 25 are inserted.

In addition to these components mentioned, the yoke device 34 has only one further component in the form of a yoke part 36, which is simultaneously assigned to both coils 16 and extends in the intermediate region 23 already mentioned. In this way, it can be penetrated by the magnetic fields of both coils 16, whose field lines run in the yoke part 36 in its longitudinal direction. This yoke part 36 is the only component of the yoke device 34 in the radial circumferential region of the externally cylindrically contoured coils 16. In this way, both the width dimensions and the height dimensions of the housing 10 can be kept very small. The coils are expediently cast into the middle housing part 10" made of plastic material.

The special feature of the yoke part 36 according to the example is that it is not a yoke part that is permanently installed from the start, but that it is formed by the fastening screw 9 already mentioned at the beginning. This fastening screw 9 passes through the control device 3 in the axial direction, with its longitudinal axis 37 being aligned parallel to the coil longitudinal axes 18, 18' and preferably, as can be seen from Figure 2, running in a common plane 27 with the coil longitudinal axes 18, 18'. The installation space required for the only necessary yoke part 36 between the two coils 16 is thus taken up by the fastening screw 9, which serves as the sole fastening means for the control device 3, so that no further

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more installation space is required for fastening screws. The fastening screw 9 therefore has a dual function in that it serves to fasten the control device 3 to the valve housing 1 and, on the other hand, forms an essential component of the yoke device 34.

It goes without saying that a material with low magnetic resistance, such as iron or steel, is chosen for the fastening screw 9.

In principle, it would be conceivable to provide several, and in particular two, fastening screws, which together form the yoke part 3 6. With reference to Figure 2, the arrangement could then be such that a screw longitudinal axis is located on both sides of the plane 27 running in the middle of the housing in the height direction 14. However, since a single fastening screw 9 is usually sufficient to securely fasten the control device 3, it is advantageous to take the path shown with a single, centrally arranged fastening screw 9.

As can be seen from Figure 1, the housing 10 of the control device 3 has a hole-like opening 38 running through the longitudinal direction 12, which also passes through the two plate-shaped yoke sections 35. The fastening screw 9 is inserted through this opening 38 from the outside, with its external head 42 resting on the outer end face of the rear housing part 10"'. Its threaded section protrudes from the end face of the front housing part 10"' facing the valve housing 1.

its housing part 10' and is screwed into a threaded hole 44 of the valve housing 1. The fastening screw 9 expediently holds the individual housing components 10', 10", 10"', of the control device 3 together so that no further connecting means are required. When the fastening screw 9 is removed, the housing 10 can be disassembled into the individual housing parts.

The manual operating device 32 already mentioned comprises two actuating slides 45, 46, of which the first (45) serves to actuate the lower valve member 7 in relation to the height direction 14 and the second (46) serves to actuate the upper valve member 7'. The actuating slides 45, 46 are arranged on the two opposite lateral outer surfaces 47, 47' of the housing part 10' and are received in surface grooves 48 of these outer surfaces 47, 47'.

Each actuating slide 45, 46 has an actuating part 51 arranged in the area of the upper side of the housing. It extends over the upper housing surface 49, for example, while maintaining an actuating distance 52. This is followed by a slide part 53 running downwards in the housing height direction 14, which is guided in a linearly movable manner in said height direction 14 on a first guide device 54 fixed to the housing. The guided slide part 53 rests with its inner surface 55 on the base surface of the associated surface groove 48. The first guide device 54 is formed in the present case by two projections fixed to the housing, which engage around the guided slide part 53 on the longitudinal edges.

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On each actuating slide 45, 46, a pin-shaped actuating part 55 is provided in the embodiment, which can protrude into the associated valve member chamber 28, 28' via a housing channel 56, 56' formed in the housing part 10" and opening out circumferentially into the associated valve member chamber 28, 28'. It tapers conically towards the free end. The actuating part 55 is located in the immediate vicinity of the valve member front side 57 associated with the valve seat 8.

Spring devices 59 supported between the housing 10 and the respective actuating slide 45, 46 pre-tension the respective actuating slide 45, 46 into the rest position shown in Figure 3. The spring devices act here between the underside of the actuating parts 51 and the facing housing part. By manually pressing on one of the actuating parts 51, the associated actuating slide 45, 46 is moved downwards, whereby its actuating part 55 acts on the associated valve member 7, 7 ¹ and lifts it off the valve seat 8. Since the stroke of the valve member, which is formed here by the movable magnet armature, is only 3/10 mm, for example, a short switching movement of the actuating slide 45, 46 is sufficient to move the desired valve member.

Each actuating slide 45, 46 has a stop tongue 58 which, in conjunction with a step 62 on the housing side, limits the upward movement and thereby specifies the rest position and the actuating distance 52.

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An angled actuating arm 63, 63' is connected to a respective guided slide section 53 for each actuating slide 45, 46. The transition area, which is however fluid, occurs via a bending zone 64. This allows the respective actuating arm 63, 63' at least slight transverse movements relative to the housing 10 and to the associated guided slide section 53 transverse to the plane 27. The possible transverse movements are indicated by double arrows 65.

A free space 66 is provided between each transversely flexible actuating arm 63, 63' and the housing 10, which allows unhindered transverse movement in the direction of the housing. In the embodiment, the free spaces 66 are formed by recesses in the lateral outer surfaces 47, 47' of the housing 10.

The bending elasticity of the actuating arms 63, 63' results in the embodiment, among other things, from the choice of material for the actuating slides 45, 46, which here consist of a single piece made of a bending-elastic plastic material.

In the first actuating slide 45 assigned to the lower valve member 7, the bending zone 64, as well as the entire actuating arm 63 connected to it, is located above the longitudinal axis 13 of the lower valve member 7. In the area of the bending zone 64, a second arm section 68 begins, which continues approximately in the extension of the guided slide section 53 and projects downwards. It ends in a bending area 69, where it merges into a first arm section 67 of the actuating arm, which extends diagonally inwards and at the same time downwards in the direction of

tion of the associated valve member 7 or its valve member chamber 28. The first arm section 67 extends in the aforementioned housing channel 56 and carries the actuating part 55 at its free end. The two arm sections 67, 68 enclose an obtuse angle, which is, for example, in the range of 13 0°.

The housing channel 56 has an oblique course corresponding to the first arm section 67 and thus opens obliquely from above and outside into the valve member chamber 28. It expediently forms an oblique guide for the first arm section 67, i.e. it is able to support the first arm section 67 laterally in such a way that it can be moved in the oblique direction 74 of the housing channel 56.

If pressure is exerted on the application section 51 of the first actuating slide 45, the latter is displaced downwards, whereby the actuating arm 63 is pivoted inwards towards the housing and the first arm section 67 is displaced along the inclined guide 70 in the direction of the valve member chamber 28 due to the transverse support provided by the inclined guide 70. The pivoting paths are minimal, they are generally in the range of a few tenths of a millimeter.

When the valve member 7 is in the appropriate position, the associated valve member chamber 28 is under internal pressure of the actuating fluid. To prevent the fluid from escaping via the housing channel 56, a sealing ring 75 is arranged in the latter, enclosing the free-ending first arm section 67. It works

expediently a cylindrical part of the first arm section 67, preferably with the actuating part 55. The sealing ring 75 can form the inclined guide 70 if designed accordingly.

It is recommended that the actuating slide 45 is also supported on the outside, at least in the area of the actuating arm 63, which is done, for example, via a second guide device 76, which is constructed in a similar way to the first guide device 54. It prevents the actuating arm 63 from buckling outwards when the first actuating slide 45 is pressed down and thus forms an effective support for the desired displacement of the first arm section 67 inwards.

It may be expedient to provide a further bending option between the two arm sections 67, 68. For example, this is the case if the bending area 69 is designed as a bending joint. This is achieved here by a material weakening 73 in the bending area between the two arm sections 67, 68.

As already mentioned, the transition between the guided slide section 53 and the second arm section 68 can be fluid. The latter can, for example, begin immediately after the first guide device 54.

The mentioned stop tongue 58 can be provided on the guided slide section 53 or, as in the present case, on the second arm section 68, from which it extends obliquely inwards towards the housing

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and at the same time upwards, with its free end engaging in the free space 66 formed by a groove. The upper limit of this free space 66 is formed by the step 62 which limits the slide travel.

The stop tongue 58 is designed to be resiliently deflectable with respect to the slide section that supports it. When force is applied from the inside, it can be pressed into a window-like recess 76 of the actuating slide 45. This makes slide assembly easier because the stop tongue 58 can move out of the way when the actuating slide is inserted into the recess 76 and can spring back into the free space 66 when it is reached.

In the second actuating slide 46 assigned to the upper valve member 7', the bending zone 64 is located considerably below the upper valve chamber 28'. It is located, for example, approximately in the height range of the lower valve member chamber 28. The guided slide section 53 therefore extends relatively far downwards and, in the embodiment, is also guided in its linear movement in the lower area by a second guide device 76.

Between the upper loading section 51 and the bending zone 64, the guided slide section 53 has an opening 78. The strip-shaped second arm section 68' of the actuating arm 63', which adjoins the bending zone 64, runs through this. The second arm section 68' therefore extends upwards in the opening 78, whereby it is laterally

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web-like longitudinal sections of the slide section 53. It ends at the top in a bending area 69', which is higher than the longitudinal axis 13 of the associated valve member 7'. It is located approximately at the level of the outer mouth of the associated housing channel 56'. The bending area 69' is followed by a first arm section 67' of the actuating arm 63', which, like the first arm section 67 of the first actuating slide 45, runs diagonally downwards and inwards in the direction of the associated valve member chamber 28'. The first arm section 67' is thus bent back practically like a hook and forms an acute angle with the second arm section 68', for example in the range of 45°. The design of the housing channel 56' as an inclined guide 70 including the arrangement of a sealing ring 75 corresponds to the design of the first actuating slide 45.

If the second actuating slide 46 is pressed downwards, the first arm section 67' interacts with the inclined guide 70 and is forced along the inclined direction 74 of the housing channel 56' in the direction of the valve member 7', whereby the flexible suspension of the actuating arm 63' enables the required relative transverse movement 65 with respect to the guided slide section 53.

The second actuating slide 46 also has a spring-elastic deformable stop tongue 58, which is formed here in the area of the bending zone 64 and engages in a housing groove 79 delimited by the step 62 in a corresponding manner as described above.

Claims (14)

G 17 057 - lens 29 May 1995 Festo KG, 73734 Esslingen Control device for a multi-way valve Claims 1. Control device for a multi-way valve, with a housing (10) having a height direction (14) which is suitable for accommodating two electromagnets (15, 15') arranged next to one another, each of which has a coil (16), the coils (16) being arranged on parallel axes in such a way that they lie one above the other with sections (22) of their outer jacket surfaces facing one another in the housing height direction (14), and each coil (16) being assigned a valve member (7, 7') which is to be actuated and which is adjustable in the coil longitudinal direction (18, 18') and which works together with a valve seat (8), and with a manual actuating device (32) which has an actuating slide (45, 46) for each valve member (7, 7') for its manual actuation, which slide extends from a position in the area the loading part (51) located on the upper side of the housing (49) with a slide part (53) guided longitudinally displaceably on the housing (10) in its height direction (14) extends downwards in the housing height direction (14) and has an actuating part (55) arranged in the region of the associated valve member (7, 7 ¹ ) which acts on the associated valve member (7, 7 ¹ ) when the actuating slide (45, 46) is moved in the housing height direction (14), wherein at least the first actuating slide (45) provided for actuating the lower valve member (7) associated with the lower coil (16) runs laterally past the upper valve member (7 ¹ ), characterized in that at least one actuating slide (45, 46) has an actuating arm (63, 63') carrying the associated actuating part (55), which has a transverse movement via at least one (65) with respect to the housing (10) enabling bending zone (64) is elastically bendably connected to the guided slide part (53), and that the actuating arm (63, 63') has an angled course towards its actuating part (55), wherein the bending region (69, 69') is higher than the longitudinal axis (18, 18') of the associated valve member and the freely ending first arm section (67, 67') adjoining the bending region (69, 69') and provided with the actuating part (55) runs obliquely inwards and at the same time downwards in the direction of the associated valve member (7, 7') and cooperates with an inclined guide (70) fixed to the housing. 2. Control device according to claim 1, characterized in that the inclined guide (70) is formed by an inclined housing channel (56, 56') into which the free-ending first arm section (67, 67') of the actuating arm (63, 63') engages at least with its actuating part (55). 3. Control device according to claim 2, characterized in that a sealing ring (75) enclosing the free-ending first arm section (67, 67') of the actuating arm (63, 63') is arranged in the housing channel (56, 56') forming the inclined guide (70). 4. Control device according to one of claims 1 to 3, characterized in that the bending region (69, 69') is designed as a bending joint, expediently by means of a material weakening (73). 5. Control device according to one of claims 1 to 4, characterized in that the actuating slide (45, 45') is spring-loaded into a starting position which is predetermined by the interaction of a stop tongue (58) projecting obliquely inwards and at the same time upwards with a housing step (62). 6. Control device according to claim 5, characterized in that the stop tongue (58) is designed to be resilient, such that it can be deflected elastically and resiliently transversely to the displacement direction (14) of the actuating slide (45, 46). 7. Control device according to one of claims 1 to 6, characterized in that in the first actuating slide (45) the bending zone (64) and expediently the entire closing actuating arm (63) is arranged above the longitudinal axis {18') of the lower valve member (7). 8. Control device according to one of claims 1 to 7, characterized in that in the second actuating slide (46) the bending zone (64) is arranged below the longitudinal axis (18) of the upper valve member (7 ¹ ), from where the second arm section (68 ') of the actuating arm (63 ') projects upwards to the bending region (69 '). 9. Control device according to one of claims 1 to 8, characterized in that a respective actuating slide (45, 46) is arranged on the lateral outer surface (47, 47') of the housing (10) and is expediently at least partially received in a surface groove (48). 10. Control device according to one of claims 1 to 9, characterized in that the coil longitudinal axes (18, 18') run in a common plane (27) aligned in the housing height direction (14). 11. Control device for a multi-way valve, with two electromagnets (15, 15') arranged next to one another in a housing (10), each of which is assigned a valve member (7, 7 ¹ ) to be actuated, each electromagnet (15, 15') having a coil (16), and the coils (16) being arranged parallel to one another at a distance from one another in such a way that sections (22) of their outer jacket surfaces face one another and an intermediate region (23) is present between the coils (16), and with a · ·· * * #·♦ · ■ · % ··· ·· ·· the yoke device (34) arranged in the immediate vicinity of the coils (16) for conducting the magnetic fields of both coils (16), which has as the only component arranged in the area surrounding the outer surface of the coils (16) a yoke part (36) arranged in the intermediate area (23), which is assigned jointly to both coils (16) and can be longitudinally penetrated by field lines of the magnetic fields of both coils (16), in particular according to one of claims 1 to 10, characterized in that the yoke part (36) assigned jointly to both coils (16) is formed by at least one fastening screw (9) of the control device (3) which passes through the housing (10) and runs parallel to the longitudinal axes (18, 18') of the coils. 12. Control device according to claim 11, characterized in that the yoke part (3 6) is formed by a single, in particular centrally arranged fastening screw (9). 13. Control device according to claim 12, characterized in that the longitudinal axis (37) of the fastening screw (9) runs in a common plane (27) with the coil longitudinal axes (18, 18'). 14. Control device according to one of claims 11 to 13, characterized in that the two coils (16) are flanked on at least one and preferably on both end faces by a common, in particular plate-shaped yoke part (35) through which the at least one fastening screw (9) acting as a yoke part (36) passes.