DE102016107766A1 - Solenoid valve and operating procedures - Google Patents

Abstract

The invention relates to a solenoid valve (1), in particular 2/3-way valve comprising coil means (2) and by energizing the coil means (2) against the spring action of a first return spring (16) and a second return spring (17) between different switching positions relative a core (3) adjustable armature (4), which is operatively connected to a pilot closing body (11) for cooperation with a pilot valve seat (15) and with a valve closing body (12) for cooperation with a valve seat (14) such that in one Opening switching position of the pilot-closing body (11) of its pilot valve seat (15) and the valve closing body (11) from its valve seat (14) is spaced and in a Schließschaltstellung the pilot-closing body (11) at its pilot valve seat (15) and the valve closing body (12) at its valve seat (14) is applied and that arranged in an axially between the opening switching position and the closing switch position Pilot switching position of the valve closing body (12) from the valve seat (14) is spaced and the pilot closing body (11) on the pilot valve seat (15) with the recess of a pilot port (23) is applied through which a pilot volume flow can flow, wherein the first return spring (16) and the second return spring (17) are formed and arranged, in particular biased, are that in the opening switching position and / or the intermediate switching position, a first spring force of the first return spring (16) is less than a second spring force of the second return spring (17).

Description

The invention relates to a solenoid valve, more precisely a pilot switching valve, according to the preamble of claim 1, in particular in the form of a 2/3-way valve, preferably for use in a coolant circuit of a motor vehicle. Furthermore, the invention relates to a method for operating such a solenoid valve.

Are known n / 3-solenoid valves in the center-centric slider design. In this case, two springs center the slide in a central position, wherein the slider is deflectable by two reluctance in both directions. In addition, lever-operated slide valves are known which are pressed by a spring to a locking mechanism - by adjusting the catch, the various positions or switching positions are approached. Also known from the prior art switching valves with cascaded springs are known, for example from the DE 42 364 82 A1 , of the DE 199 08 102 C1 , of the DE 10 2007 009 167 A1 , of the DE 10 2013 217 580 A1 , of the EP 0 595 014 A1 or the DE 37 00 356 C2 ,

The disadvantage of a slide valve design is the function-related leakage in the closed position and also the sensitivity to contamination. In addition, the required high-precision and therefore cost-intensive production of the sliding pair of disadvantage. The disadvantage of the switching valves with cascaded springs, as this example in the DE 10 2013 216 568 A1 are described, is that the return springs act on each switching position to each other and thus add up the tolerances.

Based on the aforementioned prior art, the present invention seeks to provide an improved switching valve, which is less critical to tolerance. In addition, the pilot switching position (throttle position) and the closed switching position (closed valve position) should be very accurate and tolerance defined as possible. Furthermore, the object is to provide a method for operating such an improved switching valve.

This object is achieved with respect to the switching valve with a solenoid valve having the features of claim 1, i. in a generic electromagnetic valve, characterized in that the second return spring is disposed spring-loading the valve body axially in the direction of the valve seat, and that the armature is adjustable from the open switching position until reaching the intermediate switching position exclusively against the spring force of the first return spring.

With regard to the method of operation, the object is achieved with the features of claim 12, i. in a generic operating method in that the adjustment of the armature from the open position into the intermediate switching position takes place exclusively against the spring force of the first return spring and / or that an adjustment of the armature against the spring force of both the first and the second return spring exclusively on the way of the Intermediate switching position takes place in the closed position, ie the second return spring is displaced from the opening shaft position into the intermediate shaft position only along the adjustment direction, without a force being applied to the second return spring.

Advantageous developments of the invention are specified in the subclaims.

All combinations of at least two features disclosed in the description, the claims and / or the figures fall within the scope of the invention. In order to avoid repetition, features disclosed according to the device should be regarded as disclosed according to the method and be able to be claimed. Likewise, according to the method disclosed features should also be considered as disclosed device and claimable.

The solenoid valve according to the invention is a pilot switching valve, in which the armature can be adjusted by energizing the coil means with different high (effective) coil currents between an open switch position, a closed switch position and an intermediate switch position (throttle switch position or pilot switch position), wherein the armature both with a pilot closing body and is operatively connected to a valve closing body, to this between a cooperating with the respective seat (valve seat or pilot valve seat) position in which the respective closing body rests against the associated seat and a position spaced from the respective seat position. In the opening switching position, both the pilot-closing body and the valve-closing body are spaced from its valve seat, while in the closed switching position the pilot-closing body abuts against its pilot valve seat and the valve-closing body against its valve seat in order to completely prevent a medium flow that can be controlled by the solenoid valve, while in FIG the intermediate switching position of the valve closing body located axially between the opening switching position and the closing switching position is lifted from its valve seat and only the pilot-closing body bears against its pilot valve seat and thereby keeps a throttle opening open in order to reduce or reduce the opening switch position; to flow throttled medium volume flow.

In order to adjust the armature from the opening switching position to the intermediate switching position, the coil means must be energized via a suitable control unit with a first coil current which is dimensioned so that the spring force of the first return spring is overcome, so that the pilot closing body come into contact with its pilot valve seat can, wherein the first coil current is further dimensioned so that the generated electromagnetic force is not sufficient nor system of the pilot-closing body on the pilot valve seat in addition to overcome the spring force of the second return spring. To achieve this and also to bring the valve closing body to bear against its valve seat, the coil means must be energized via the control unit with a larger second coil current, which is so dimensioned to overcome the spring force of the second return spring in addition to the spring force of the first return spring. In this case, the first spring force of the first return spring and the second spring force of the second return spring in the opening switching position and / or the intermediate switching position of the armature are coordinated so that the first spring force is smaller than the second spring force.

The specification or setting of the first and second spring force in the opening switching position can be selected by selecting appropriate spring constants, wherein preferably the spring constant of the second return spring is larger, in particular significantly greater than the spring constant of the first return spring - additionally or alternatively, the different spring force be adjusted by appropriate choice of the spring preloads (springs with the same or different spring constant).

In contrast to solenoid valves of the prior art erfindungemäß is now provided according to the invention, that the second return spring axially in the adjustment of the armature in the adjustment of the armature when energized the coil means in the direction of its valve seat spring force and is further arranged so that the spring force of the second return spring an adjustment of Anchor from the open position to the intermediate switching position does not counteract, so that the armature from the opening switching position until reaching the intermediate switching position exclusively against the spring force of the return spring (ie not additionally against the spring force of the second return spring) is adjustable. In other words, the second return spring is arranged such that it is compressible only after installation of the pilot-closing body on the pilot valve seat and a corresponding application of force by the armature or an energization of the coil means with the second coil current. In contrast to the prior art, the power is transmitted from the armature to the pilot-closing body on the way from the opening switching position to the intermediate switching position not via the second return spring, but exclusively via the first return spring. The second return spring is thus displaced axially in the compression of the first return spring only between the opening switch position and the intermediate switch position without resulting force application, i. the axially spaced abutment or support elements (for example, a plunger-side abutment and the pilot closing body), on which the second return spring is supported, are not subjected to force against each other on this adjustment. As a result, the disadvantage of the prior art is overcome, that the springs not permanently, but only from the intermediate switching position to the closing position interact with each other, so that do not add up tolerances until reaching the intermediate position in contrast to the prior art. As a result, a lower tolerance dependence in the intermediate switching position (throttle position) is achieved than in the prior art. In addition, a separate adjustment of the spring engagement points is possible, both geometrically and by the choice of a corresponding Vorstellkraft.

The throttle rate or throttle position (intermediate switching position) is defined as a whole comparatively tolerance-free.

Preferably, in the closed switching position between armature and core still a residual axial gap is present and the closed switching position is defined by interaction between the valve closing body and the associated valve closing body and the associated valve seat (stop).

Constructively advantageous is a variant in which the first and the second return spring are axially spaced and are most preferably located on two spaced apart sides of the core, which in turn is preferably penetrated by a later to be explained plunger.

Preferably, the first return spring is supported with an axial end directly or indirectly on the armature and with the opposite or remote from the further axial end directly or indirectly on the core, is thus sandwiched between armature and core, so that the first return spring in an adjustment the armature between opening switch position and intermediate switch position and between the intermediate switch position and the closed switch position is compressed.

From a constructive point of view, it has proven to be advantageous if both the valve closing body and the pilot closing body, in particular the end, are arranged on an elongate or along the adjustment axis of the armature extending plunger. In particular, for assembly reasons, it is advantageous if the ram and the armature are separate from one another but fixed to one another, for example, by screwing, welding or pressing. In principle, a variant embodiment is conceivable in which the plunger is formed, at least in sections, by the armature itself, ie monolithically with it. In principle, it is preferred if the plunger is arranged such that it axially passes through the first return spring and / or the second return spring and / or the core preferably arranged between the return springs.

It is particularly preferred if the second return spring together with the plunger is axially adjustable, in particular such that these only after reaching the intermediate switching position (starting from the opening switching position) by pressing the pilot closing body against the pilot valve seat due to the corresponding energization of the coil means with the second ( higher) coil current is compressible. To achieve this, it has proven to be advantageous if an abutment is formed or fixed on the plunger, on which the second return spring is axially supported with an end remote from the pilot closing body. Preferably, the second return spring is supported with the axial end oriented in the direction of the pilot closing body indirectly or directly on the pilot closing body, in particular in such a way that the second return spring is compressed after contact of the pilot lock body with the pilot valve seat and an axial further movement of the armature and the plunger, since Distance between the valve closing body and the relative to the plunger position fixed abutment is reduced or seen relative to the plunger, the pilot-closing body is moved away from the armature facing away from the axial end in the direction of anchor.

Preferably, the abutment is arranged in all switching positions of the armature equidistant from the valve closing body, which is preferably arranged immovable or stationary in all switching positions relative to the plunger.

Particularly preferred is an embodiment in which the valve closing body forms an indirect or immediate axial stop for the pilot valve body in the opening switching position until reaching the intermediate switching position and axially from the valve closing body with compression of the second return spring when energized with the second coil current, i. lifts off on the way of the armature of the intermediate switching position in the Schließschaltstellung.

Particularly advantageous is an embodiment of the solenoid valve according to the invention has been found in which the valve seat and the pilot valve seat are arranged radially side by side, in particular in a common axial plane or axial position. In other words, preferably the valve seat and the pilot valve seat are not or alternatively only slightly offset axially. To be particularly advantageous, it has been found that the valve seat and the pilot valve seat, but not mandatory in a radial juxtaposition, are arranged on a common valve seat component, which in the opening switching position both from the valve closing body and the pilot closing body and in the intermediate switching position exclusively from the valve closing body axially is spaced.

Especially useful is a radial interleaving or nesting of the valve closing body and the pilot closing body, of which preferably at least one, preferably both cup-shaped, in particular to cooperate with a pot bottom axially spaced pot opening peripheral edge with the respectively associated seat. It is particularly expedient to arrange the valve closing body radially inside the pilot closing body. It has proven particularly expedient to return the valve closing body axially in the opening switching position and the intermediate switching position relative to the front action end of the pilot-closing body in the direction of the armature, this offset being overcome by compressing the second return spring after passing through the intermediate switching position. Particularly expedient is an embodiment in which the pilot-closing body and the valve closing body are arranged axially outside of the armature, the core and the coil means receiving, preferably magnetflussleitenden housing of the solenoid valve, which is preferably penetrated axially by the aforementioned plunger.

The invention also leads to a method for operating a solenoid valve according to the invention. According to the invention, that the adjustment of the armature from the opening switching position in the intermediate switching position takes place exclusively against the spring force of the first return spring, which does not additionally counter to the spring force of the second return spring and / or that an adjustment of the armature against the spring force of both the first return spring Also, the second return spring takes place exclusively on the way from the intermediate switching position in the closed position. Preferably takes place in the frame the method, the energization of the coil unit with different effective coil currents via a solenoid valve in the context of a valve system associated control unit. The system preferably comprises a coolant circuit of an internal combustion engine, in particular of a motor vehicle, within the scope of which the method according to the invention is used or the solenoid valve according to the invention fulfills its function.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawings.

These show in:

1 a solenoid valve according to the invention in an open position,

2 : the solenoid valve according to 1 in its intermediate position, and

3 : the aforementioned solenoid valve (almost) in its closed position.

In the figures, like elements and elements having the same function are denoted by the same reference numerals.

In the figures, designed as a 3/2-way valve electromagnetic pilot valve (solenoid valve) 1 shown. This comprises an axial along an adjustment axis V by energizing coil means 2 relative to a stationary core 3 adjustable anchor 4 , The coil means 2 include an energizable winding 5 on a coil carrier designed here as a plastic injection-molded part 6 is arranged, which radially outside the armature 4 surrounds. The anchor 4 is in the specific embodiment, an armature guide tube 7 within which is the anchor 4 is guided at its axial adjustment movement. Inside the anchor 4 there is a through hole 8th for axial pressure balance on both opposite axial sides of the armature 4 to take care of an adjusting movement.

At the anchor 4 is an elongated pestle 9 set the core 3 axially penetrated and axially from a housing 10 protrudes, which the coil means, the anchor 4 and the core 3 receives and also has flow-conducting properties to close the magnetic circuit.

In one of the anchor 4 remote end portion of the plunger 9 are a cup-shaped pilot closing body 11 and a radially encapsulated therein, also cup-shaped valve closing body 12 These are by adjusting the anchor 4 relative to a common valve seat component 13 adjustable, which is fixed in place and a valve seat 14 for sealing cooperation with the valve closing body 12 and a radially adjacent thereto, located in the same axial plane pilot valve seat 15 forms the axial concerns of the pilot closing body 11 ,

Out 1 It can be further seen that sandwiched between the anchor 4 and the core 3 a first return spring 16 is arranged, which has a smaller spring constant in the specific embodiment than a second return spring 17 , which is received axially between one on the plunger 9 trained and permanently fixed to this arranged abutment 18 and the pilot lock body 11 , In addition or as an alternative to different spring constants, different spring forces can be achieved in the illustrated open switch position and the intermediate switch position (cf. 2 ) can be achieved by selecting appropriate spring voltages. In any case, the first spring force acting on the respectively supporting components is the first return spring 16 less than the second spring force of the second return spring 17 ,

How out 1 can be seen, the second return spring is supported 17 directly on the ram-resistant abutment 18 and opposite to the relative to the plunger 9 movable pilot closing body 11 from. This in turn is supported axially directly on the ram or permanently fixed to the plunger 9 arranged valve closing body 12 which is clamped between a ram-proof ring shoulder 19 and an end axial locknut 20 , In the illustrated opening switching position of the armature 4 , one in the drawing plane top or by the core 3 represents a remote end position, a maximum medium flow through a range axially between the seats 14 . 15 and the closing bodies 11 . 12 in the direction of the arrow 21 or in the opposite directions, depending on the connection or arrangement of the solenoid valve 1 in a fluid circuit, in particular in a cooling circuit of an internal combustion engine, preferably a motor vehicle.

It can be seen that, in the opening switch position shown, the armature 4 via an elastomeric ring seal 22 , which is received in a retaining groove at the front, at the bottom of the sleeve-shaped armature guide tube 7 supported.

The following are the 2 and 3 explained to avoid repetition only differences in the switch positions - in terms of similarities and in particular the structure of the solenoid valve 1 will be on 1 with associated figure description referenced.

Will the coil means 2 , more precisely, their winding 5 flows through from the opening switching position with a first coil current, the armature moves 4 in the in 2 shown intermediate switching position (throttle position), which is defined by striking or concern of the pilot-closing body 11 at the pilot valve seat 15 , with the exception of a pilot hole 23 (Throttle opening) to ensure a pilot volume flow in the direction of arrows 24 or the opposite directions. It can be seen that by this adjusting movement in comparison to the opening switching position, the first return spring 16 was (further) compressed, the second return spring 17 However not. The power transmission from the anchor 4 on the pilot valve seat during this adjustment until reaching the intermediate switching position was carried out exclusively on the first return spring 16 or under compression of the first return spring 16 - while the second return spring 17 not involved in the transmission. Until reaching the intermediate switching position and in the intermediate switching position takes place, as explained, no compression or Komprimierkraftbeaufschlagung the second return spring 17 , so that the relative position between pilot closing body 11 and valve closing body 12 remains unchanged. In other words, the adjustment movement took place in the in 2 shown intermediate switching position exclusively under application of force to the first return spring 16 , The first coil current is dimensioned so that this is the second return spring 17 not compressed after reaching the intermediate representation. Now become the coil means 2 energized with a second coil current, which is greater than the first coil current becomes the armature 4 continue towards the core 3 adjusted, and that until the sealing contact of the valve closing body 12 at its from the valve seat member 13 trained valve seat 14 , In the illustration according to 3 this end position is not quite reached.

In other words, in the closed switch position, a sealing contact of the valve closing body 12 at the valve seat 14 given, so that no medium volume flow can flow more. In the closed position is a Restaxialspalt 25 between anchors 4 and core 3 given. The adjusting movement from the intermediate switching position into the closed switching position was or takes place with simultaneous compression of the second return spring 17 and increasing the axial distance between the pilot-closing body 11 and the valve closing body 12 , wherein during this movement step anchors 4 and pilot lock body 11 under compression of the second return spring 17 approach along the adjustment axis V.

LIST OF REFERENCE NUMBERS

1

Solenoid valve

2

coil means

3

core

4

anchor

5

winding

6

coil carrier

7

armature guide

8th

Through Hole

9

tappet

10

casing

11

Pilot closing body

12

Valve closing body

13

Valve seat member

14

valve seat

15

Pilot valve seat

16

first return spring

17

second return spring

18

abutment

19

annular shoulder

20

locknut

21

arrow directions

22

ring seal

23

Pilot orifice (s)

24

arrow directions

25

Restaxialspalt

V

adjustment axis

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4236482 A1 [0002]
• DE 19908102 C1 [0002]
• DE 102007009167 A1 [0002]
• DE 102013217580 A1 [0002]
• EP 0595014 A1 [0002]
• DE 3700356 C2 [0002]
• DE 102013216568 A1 [0003]

Claims (13)

Solenoid valve ( 1 ), in particular 2/3-way valve, comprising coil means ( 2 ) and one by energizing the coil means ( 2 ) against the spring action of a first return spring ( 16 ) and a second return spring ( 17 ) between different switching positions relative to a core ( 3 ) adjustable anchor ( 4 ), which with a pilot closing body ( 11 ) for cooperation with a pilot valve seat ( 15 ) and with a valve closing body ( 12 ) for cooperation with a valve seat ( 14 ) is operatively connected, such that in an opening switching position of the pilot-closing body ( 11 ) from its pilot valve seat ( 15 ) and the valve closing body ( 11 ) from its valve seat ( 14 ) is spaced and in a closed switching position of the pilot closing body ( 11 ) at its pilot valve seat ( 15 ) and the valve closing body ( 12 ) at its valve seat ( 14 ) is applied and that in an axially between the open switching position and the closed position switched pilot switching position of the valve closing body ( 12 ) from the valve seat ( 14 ) is spaced and the pilot closing body ( 11 ) on the pilot valve seat ( 15 ) with the opening of a pilot opening ( 23 ) is applied through which a pilot volume flow can flow, wherein the first return spring ( 16 ) and the second return spring ( 17 ) are formed and arranged, in particular biased, are that in the opening switching position and / or the intermediate switching position, a first spring force of the first return spring ( 16 ) is less than a second spring force of the second return spring ( 17 ), characterized in that the second return spring ( 17 ) the valve closing body ( 12 ) axially in the direction of the valve seat ( 14 ) is arranged spring-loading, and that the armature ( 4 ) from the opening switching position until reaching the intermediate switching position exclusively against the spring force of the first return spring ( 16 ) is adjustable. Electromagnetic valve according to claim 1, characterized in that the first ( 16 ) and the second return spring ( 17 ) are axially spaced. Electromagnetic valve according to one of the preceding claims, characterized in that the first return spring ( 16 ) at the very core ( 3 ) and at the other end at anchor ( 4 ) is supported. Electromagnetic valve according to one of the preceding claims, characterized in that the valve closing body ( 12 ) and the pilot closing body ( 11 ), preferably end, on one, preferably the first return spring ( 16 ) and / or the second return spring ( 17 ) and / or the core ( 3 ) axially penetrating, ram ( 9 ) are arranged on the anchor ( 4 ) or monolithically formed with this. Electromagnetic valve according to claim 4, characterized in that the second return spring ( 17 ) at one end on an axially between the valve closing body ( 12 ) and the anchor ( 4 ) and / or the first return spring ( 16 ), preferably in all switching positions of the armature ( 4 ) equidistant to the valve closing body ( 12 ), abutments ( 18 ) of the plunger ( 9 ) and at the other end on the pilot closing body ( 11 ) is supported. Electromagnetic valve according to one of the preceding claims, characterized in that the pilot-closing body ( 11 ) only when adjusting the anchor ( 4 ) between the intermediate switching position and the Schließschaltstellung relative to the valve closing body ( 12 ) while compressing the second return spring ( 17 ) is adjustable. Electromagnetic valve according to one of the preceding claims, characterized in that the valve closing body ( 12 ) in the opening switching position of the second return spring ( 17 ) against the pilot closing body ( 11 ) is acted upon by spring force and / or in the opening switch position and / or the intermediate switch position axially on the pilot valve body ( 15 ) is supported. Electromagnetic valve according to one of the preceding claims, characterized in that the valve seat ( 14 ) and the pilot valve seat ( 15 ) radially adjacent to each other, in particular at the same axial position, and / or on a common valve seat member ( 13 ), preferably axially spaced from the first ( 16 ) and the second return spring ( 17 ) are arranged. Electromagnetic valve according to one of the preceding claims, characterized in that, preferably cup-shaped, valve closing body ( 12 ) and the, preferably cup-shaped, pilot-closing bodies ( 11 ) are arranged radially in one another, in particular such that the valve closing body ( 12 ) radially in the pilot closing body ( 11 ) is received and / or the valve closing body ( 12 ) until reaching the closing position axially relative to a supporting end of the pilot-closing body ( 11 ) for supporting on the pilot valve seat ( 15 ) is relocated. Electromagnetic valve according to one of the preceding claims, characterized in that the pilot-closing body ( 11 ) and the valve closing body ( 12 ) outside of the anchor ( 4 ), the core ( 3 ) and the coil means ( 2 ) receiving housing ( 10 ) of the solenoid valve ( 1 ) are arranged. Electromagnetic valve according to one of the preceding claims, characterized in that the armature ( 4 ) by energizing the coil means ( 2 ) with a first coil current axially from the open position against the spring force of the first Return spring ( 16 ) to, preferably exclusively, is adjustable in the intermediate switching position and by energizing with a second coil current, which is greater than the first coil current from the opening switching position and / or intermediate switching position against the spring forces of the first ( 16 ) and the second return spring ( 17 ) is adjustable in the Schließschaltstellung. Method for operating a solenoid valve ( 1 ) according to any one of the preceding claims, wherein the armature ( 4 ) from the open position by energizing the coil means ( 2 ) is adjusted with a first coil current in the closed position and thereby in the opening switching position by the pilot valve seat ( 15 ) and the valve seat ( 14 ) flowing medium volume flow is reduced to a smaller medium pilot volume flow and that the armature ( 4 ) for closing the solenoid valve ( 1 ) from the opening switching position or the intermediate switching position into the closed switching position by energizing the coil means ( 2 ) is adjusted with a second coil current, which is greater than the first volume flow, characterized in that the adjustment of the armature ( 4 ) from the opening switching position in the intermediate switching position exclusively against the spring force of the first return spring ( 16 ) and / or that an adjusting movement of the armature ( 4 ) against the spring force of both the first ( 16 ) and the second return spring ( 17 ) takes place exclusively on the way from the intermediate switching position into the closed switching position. A method according to claim 12, characterized in that the valve closing body ( 12 ) and the pilot valve body ( 11 ) are arranged radially adjacent to one another in the closed position and / or with the same valve seat element ( 13 ) interact.

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