DE19951665B4 - Solenoid valve, in particular for hydraulic brake systems with slip control - Google Patents

Abstract

Electromagnetic valve, in particular for slip-controlled wheel brakes, having a valve tappet (4) which has a valve closing member (9) in a valve housing (3, 25) consisting of a cold-impact or cold-extruded part, with a valve seat receiving body (7, 22), which forms with the valve housing (3, 25) and the valve stem (4) independently operable first subassembly, and with a the valve stem (4) actuated armature (13) arranged by means of a valve housing (3, 25) Valve spool is electromagnetically actuated, with a filter assembly which forms a independently manageable and pretestable second subassembly having a check valve (10) within a stepped bypass opening (12) of a plastic filter cup (11), and with a plurality in a disc-shaped bottom of the Filter pot (11) embedded filter channels (30) with the bypass opening ( 12), characterized in that the filter channels (30) extend on both sides of the bottom (29) extending transversely to the longitudinal axis of the valve grooves, and that the check valve fixing the height of the filter channel (30) in the working area of the ...

Description

The The invention relates to a solenoid valve, in particular for hydraulic Brake systems with slip control, according to the preamble of the claim 1.

such conventional, well-known valves for flow control of fluids in wheel slip controlled hydraulic brake systems diverse practical use.

From the DE 198 088 26 A1 is already known in open position solenoid valve for a slip-controlled hydraulic brake system has become known, the valve housing is executed in cartridge design, which is preferably pressed as produced from a free-cutting steel rotary member in a block-shaped valve receiving body. Also, the valve seat forming the valve plate is made of a relatively massive, preferably also made of a free-cutting steel rotary member, which is held at the lower end of the valve housing by means of caulking. The cooperating with the valve seat valve stem is guided within the valve housing and is a solid, consisting of a solid cylinder shaft part, which is supported in conjunction with a setting bushing on an end face of the armature, which is guided within the valve sleeve portion on the valve body. In order to keep the valve stem in the initial position of the solenoid valve lifted from the valve seat, a so-called. Return spring is provided coaxially with the valve stem, which presses with its one spring end the valve stem with the adjusting bush in the direction of the armature.

adversely is to be seen in the solenoid valve described above Switching behavior and the relatively large production costs, both for the preparation of the valve details as well as for the production and to use a working Overall assembly is required in a valve receiving body.

Out DE 196 35 693 A1 a solenoid valve is known with a filter assembly of the generic type, the filter bowl has a bottom, which has in the direction of a plate filter either a sleeve-shaped or disc-shaped projection in which a check valve is received. The sleeve or disc-shaped projection must be formed correspondingly expensive on the filter cup made of plastic, as between the filter bowl and the projection a precise annular gap is required to seal the plate filter by means of a press fit securely on the filter pot.

Also the off DE 196 35 690 A1 and DE 199 49 222 A1 known solenoid valves have a filter assembly with the DE 196 35 693 A1 described features.

Therefore It is the object of the invention, while avoiding the aforementioned Disadvantages of a solenoid valve of the specified type, in particular the opened in basic position Design, as simple as possible and therefore cost-effective to produce, which has a miniaturized structure and its Parts are pretestable in their function.

According to the invention Asked task for a solenoid valve of the type mentioned by the features of claim 1.

The measures indicated in the dependent claims expedient embodiments of the invention are given in connection with the other features and advantages of the invention below with reference to several drawings according to the 1 and 2 be shown and explained in detail.

It show in detail:

1a to 1e a first expedient embodiment of the invention with reference to an open in the basic position solenoid valve,

1b to 1e the installation steps for setting the Magnetankerrestluftspalts for in 1a explained solenoid valve,

2 an application of the invention for a normally open solenoid valve, which is provided with a reinforced valve housing.

First, based on the 1a the basic overall structure of the open in the basic position solenoid valve will be described. The solenoid valve shown in cross section has a sleeve-shaped valve housing 3 on, at both end areas with guide surfaces 3a . 3b is provided at one end a dome-shaped valve sleeve 1 and at the other end a pot-shaped valve seat receiving body 7 to keep. The valve housing 3 thus forms a suitable for the aforementioned parts, bush-shaped central body, which at the same time the magnetic core 25 united in itself. For the purpose of a cost-effective production of the aforementioned parts is the valve housing 3 from a Kaltfließpreßteil or cold impact part, the valve sleeve 1 and the cup-shaped valve seat receiving body 7 formed as deep-drawn parts, wherein the valve seat receiving body 7 in the cup-shaped bottom, preferably by means of an embossing process, the valve seat surface for receiving the valve closure member 9 on the valve lifter 4 on has.

Another, manufacturing technology and functionally useful construction results from the design of the valve lifter 4 As a plastic part, which inevitably works very quiet and with minimal inertia responsive and can be produced sufficiently precise and extremely cost-effective. Through the selected contour of the valve tappet 4 is a particularly favorable placement of a return spring 8th possible concentrically on the valve lifter 4 is applied, so that the return spring 8th with its one end of the turn on a funnel-shaped extension of the pushrod shank and with its other end of the turn at the bottom of the cup-shaped valve seat receiving body 7 supported. The valve closure member 9 forms with the valve lifter 4 preferably a homogeneous unit. If desired or required, it can also consist of another heterogeneous material and by well-known fastening methods on the plunger 4 to be appropriate. Furthermore, the valve tappet 4 at least one longitudinal groove or a central longitudinal bore for pressure equalization between the both sides of the magnetic core 25 located cavities 15 . 16 on. The valve lifter 4 can for example be designed as a polygonal profile.

On the spherical valve closing member 9 opposite bottom of the cup-shaped valve seat receiving body 7 there is a check valve 10 , also designed as a plastic or steel ball, in a over the valve seat receiving body 7 deferred filter pot 11 is held, which is also made of plastic. The check valve 10 is located in a downwardly funnel-shaped enlarged bypass opening 12 on the ground 29 of the filter pot 11 and is by means of a plate filter 31 held from below on the bottom of the pot. Between the inner end face of the plate filter 31 and the check valve 10 only remains a small axial distance to ensure the check valve function and for producing a pressure medium connection, extending in the direction of a concentric with the valve seat surface in the valve seat receiving body 7 extending pressure medium bore 27 and to below the plate filter 31 located pressure medium channel 26 extends. The pressure medium bore 27 normally provides a fluid connection between the valves through the valve closure member 9 Electromagnetically separable pressure medium channels 26 in the longitudinal and transverse direction to the valve axis in the valve carrier 6 open out. The bypass opening 12 becomes only differential pressure dependent on the check valve 10 in the direction of the plate filter 31 released to closed valve closing member 9 a pressure medium connection between the plate filter 31 upcoming pressure medium and the above the check valve 10 in the cavity 16 to allow pending pressure medium. The required pressure medium channels 30 leading to the bypass line 12 extend, can be particularly simple as transverse to the valve longitudinal axis grooves by means of plastic injection molding at the top and bottom of the filter pot 11 molding. Favored by the downwardly tapered shape of the valve seat receiving body 7 remains a sufficiently large gap from that in the side wall of the filter cup 11 injected ring filter, the pressure medium of the valve carrier 6 passing through the pressure medium channel 26 is flowed through.

The magnet armature 13 is made of a Kaltfließpreßteil or cold impact part, which is above the imaging as the magnetic core 25 effective valve housing 3 in the valve sleeve 1 extends. The magnet armature 13 is preferably made of a polygonal profile and is advantageously independent of the position of the valve stem 4 in the valve sleeve 1 out. The magnet armature 13 and the Ven tilstößel 4 thus form mutually independent loose parts which, although coupled as axial force transmission members, are self-centering independent of one another in the radial direction. Due to the fact that the valve tappet 4 and possibly also the magnet armature 13 consist of polygonal profiles, there is an unimpeded pressure equalization in the on both sides of the valve housing 3 located cavities 15 . 16 ,

The designed in cartridge design solenoid valve has only for attachment in the block-shaped valve carrier 6 one in the field of external clogging 17 relatively thin-walled portion of the valve seat receiving body 7 in the form of a border 20 on, by means of an external stemming 17 in the valve carrier 6 pressure medium tight is attached. The receiving bore 18 is designed as a stepped bore, at the level of the edge 20 is applied. The section of the valve body 3 , which deals with the guide surface 3b in the cup-shaped valve seat receiving body 7 extends, ensures a secure mounting of the aforementioned parts and also allows easy adjustment of Magnetankerrestluftspalts before the filter pot 11 in the valve carrier 6 is used.

The valve sleeve 1 and the valve receiving body 7 are not just on the guide surfaces 3a . 3b deferred, but after completed valve adjustment by means of a welded joint 21 permanently attached. Instead of the welded joint 21 Under certain conditions, alternative positive and positive fastening methods are conceivable. Except for the exception of the side of the bottom center in the filter pot 11 arranged check valve 10 all other components of the valve mentioned are arranged concentrically to the valve longitudinal axis.

As already mentioned, the armature is 13 as well as the magnetic core 25 executed as Kaltfließpreßteil or cold impact part, including, in particular, a material with the marking X8Cr17 or alternatively a material according to the marking X6Cr17 is suitable. The sleeve-shaped valve housing 3 is preferably made of free-cutting steel according to classification 1.43.03. The same material is used for the cup-shaped valve seat receiving body 7 , The pot of the valve seat receiving body 7 has at least one radially and axially extending through hole 27 . 34 on, wherein the arranged in the valve longitudinal axis through hole 27 preferably produced by means of an embossing process and the actual valve seat surface for the valve closure member 9 is limited, while the transverse thereto the valve seat receiving body 7 penetrating pressure medium bore 34 in the open valve switching position above the valve closing member 9 located pressure medium channel 26 over the through hole 27 with the below the plate filter 31 located pressure medium channel 26 combines. The sealing of the filter pot 11 in the stepped bore of the valve carrier 6 takes place by means of a press fit.

The following is for the solenoid valve after 1a the procedure for adjusting the Magnetankerrestlattspaltes with reference to the figures after the 1b to 1e described.

The 1b shows first with the return spring 8th provided valve seat receiving body 7 in a counterholder 2 used to stop. The valve seat body 7 relies for this purpose with the annular surface of its bottom and the annular surface of the edge 20 evenly at the receiving bore of the counter-holder 2 from. The valve seat receiving body 7 has in cross-section on a W-profile, which is produced by deep drawing.

To 1c first, the sleeve-shaped valve housing 3 with the guide surface 3b in the valve receiving body 7 only slightly inserted.

The insertion follows according to the 1d the insertion of the valve lifter 4 in the valve body 3 , The valve lifter 4 becomes under the action of an axial force F1 of a setting pin 23 with the valve closing member 9 against the action of the return spring 8th on the valve seat surface of the valve seat receiving body 7 pressed.

To 1e presses parallel to the adjustment pin 23 a stepped stepped adjustment plate 28 under the action of an axial force F2 on the outer face of the valve housing 3 , which gives the guide surface 3b further into the valve seat receiving body 7 shifts until also the depression in the stepped end face of the adjustment plate 28 on the end face of the valve lifter 4 strikes. The dimension of the depression in the adjustment plate 28 accordingly corresponds to the setting for the required Magnetankerrestlattspalt X. After completion of this adjustment measure the valve seat receiving body 7 with the valve body 3 welded.

The solenoid valve after 2 shows deviating from the valve design 1a one in the direction of the filter pot 11 extended hollow cylindrical valve body 3 in which at the lower stepped end a preferably designed as a deep-drawn sleeve body 22 is pressed in the function of the valve seat receiving body to the valve closure member 9 directed sleeve end has a valve seat contour preferably produced in the embossing process.

At the opposite end of the sleeve is the filter pot 11 , whose tubular projection 14 in the sleeve body 22 extends as a press connection. The lead 14 as well as in 1a a fixed aperture 33 on. To the check valve 10 against falling out of the filter pot 11 to secure it and thus position it in its position is like in 1a the plate filter 31 from the bottom until it touches the ground 29 pressed into a lid-shaped recess or optionally clipped. Characterized in that between the plate filter 31 and the lid-shaped bottom 29 at the filter pot 11 a to the check valve 10 leading filter channel 30 is formed, results in a surprisingly simple pressure fluid connection both via the check valve 10 as well as over the regular of the valve closing member 9 sealable pressure medium through hole 27 in the concentric region of the valve seat surface. The filter channel 30 sits above the check valve 10 both in the direction of the filter pot 11 injected ring filter 32 as well as one between the sleeve body 22 and the housing 3 located longitudinal groove 35 continued. Consequently, the filter cup corresponds 11 in terms of its structure and its function already in 1a pictured filter pot 11 in all essential characteristics.

Through the proposed filter pot 11 can achieve a significant component, assembly and Prüfischerfachung, including in the filter bowl 11 the check valve 10 is integrated directly and the check valve 10 in a particularly simple way by means of a plate filter 31 Safe in the ground 29 is integrated. The plate filter can also be at the same time at the bottom of the receiving bore 18 partially supported, so that a fixation of the plate filter 31 in the filter pot 11 is guaranteed.

For both valve constructions after the 1a and 2 Thus, this results in a functional filter assembly, which represents an independently manageable and pretestable subassembly of the solenoid valve. For secure attachment of the filter pot 11 on the valve body 3 or on the sleeve body 22 points the filter pot 11 a hollow cylindrical projection 14 on, the illustration concentric to the valve closure member 9 in the valve seat receiving body 7 is directed. A manufacturing technology particularly simple constructive solution for the arrangement of the check valve 10 in the filter pot 11 arises when in the ground 29 of the filter pot 11 a stepped bypass opening 12 for receiving the check valve 10 is provided, on both sides of the disc-shaped bottom 29 with filter channels 30 communicating, preferably as grooves in the ground 29 extend. The hollow cylindrical projection 14 is preferably by means of a press connection in the valve seat receiving body 7 inserted and as a plastic injection molding on the ground 29 added. They are on both sides of the ground 29 in the direction of the plate filter 31 and the ring filter 32 vertically extending wall sections of the filter cup 11 are either fluid-tight the valve body 3 (please refer 2 ) or on the wall of the valve carrier 7 (please refer 1a ). According to the 1a and 2 This results in a particularly simple mounting of the check valve 10 in the bypass hole 12 when the plate filter 31 at least in sections, the check valve 10 covered, wherein for the check valve fixing the height of the filter channel 30 in the working area of the check valve 10 at least slightly smaller than the nominal size of the check valve 10 , so that a lateral outward migration of the check valve from the filter channel 30 is excluded. In the plastic injection molding process can be at wish or need in a particularly simple way a fixed aperture 33 in the lead 14 of the filter pot 11 inject, so that separate assembly measures to dispose of a fixed panel eliminated. If used as a check valve 10 a ball check valve is to be used, are particularly well made of high-precision steel balls inserted into the filter pot bottom made by injection molding and the plate filter 31 be closed.

Furthermore, it can be seen from the figure 2 recognize that for fastening the valve housing 3 in the valve carrier 6 the valve housing 3 a relatively massive, ie strengthened alliance 5 which, as already shown in the figure 1a is known by means of a Außenverstemmung 17 covered by the housing material and thus pressure-tight in the valve carrier 6 is attached. As far as not all of the drawing after 2 apparent features are described, these correspond substantially to the explanations of the solenoid valve according to 1b to 1e ,

1

valve sleeve

2

backstop

3

valve housing

4

tappet

5

Federation

6

valve

7

Valve seat receiving body

8th

Return spring

9

Valve closure member

10

check valve

11

filter bowl

12

bypass opening

13

armature

14

head Start

15

cavity

16

cavity

17

caulking

18

location hole

19

step

20

edge

21

welded joint

22

sleeve body

23

adjusting pin

24

valve spring

25

magnetic core

26

Pressure fluid channel

27

Through Hole

28

adjustment

29

ground

30

filter channel

31

plate filters

32

ring filter

33

fixed aperture

34

Through Hole

35

longitudinal groove

X

Armature residual air gap

F1, F2, F3

personnel

Claims (11)

Electromagnetic valve, in particular for slip-controlled wheel brakes, with a valve tappet ( 4 ), which is a valve closure member ( 9 ), in a valve housing made of a cold-pressed or Kaltfließpreßteil ( 3 . 25 ), with a valve closure member ( 9 ) facing valve seat receiving body ( 7 . 22 ) connected to the valve housing ( 3 . 25 ) and the valve tappet ( 4 ) forms a independently manageable first subassembly, and with a valve tappet ( 4 ) actuating armature ( 13 ), which by means of a valve housing ( 3 . 25 ) is electromagnetically actuated, with a filter assembly which forms a self-operable as well as pretestable second subassembly comprising a check valve ( 10 ) within a stepped bypass opening ( 12 ) of a filter pot made of plastic ( 11 ), and with several in a disc-shaped bottom of the filter pot ( 11 ) recessed filter channels ( 30 ) with the bypass opening ( 12 ), characterized in that the filter channels ( 30 ) on both sides of the soil ( 29 ) extend as transverse to the valve longitudinal axis extending grooves, and that the check valve fixing the height of the filter channel ( 30 ) in the working area of the check valve ( 10 ) is smaller than the nominal size of the check valve ( 10 ). Electromagnetic valve according to claim 1, characterized in that the valve housing ( 3 . 25 ) at its from the valve closure member ( 9 ) facing away from the valve housing ( 3 . 25 ) closing valve sleeve ( 1 ), which is designed as a deep-drawn part. Electromagnetic valve according to claim 1 or 2, characterized in that the valve housing ( 3 . 25 ) at its the valve closure member ( 9 ) facing end as a sleeve body ( 22 ) carried out valve seat receiving body ( 7 ), which is produced by a compression molding or deep drawing process. Electromagnetic valve according to claim 1, characterized in that the valve stem ( 4 ) consists of a wear-resistant plastic. Electromagnetic valve according to claim 1, characterized in that on the filter pot ( 11 ) a hollow cylindrical projection ( 14 ) is provided, concentric with the valve closure member ( 9 ) on the valve seat receiving body ( 7 ). Electromagnetic valve according to one of the preceding claims, characterized in that the disc-shaped bottom ( 29 ) as a plastic injection molded part with the hollow cylindrical projection ( 14 ) having a press-fit connection with the valve seat receiving body ( 7 ) occupies. Electromagnetic valve according to claim 1, characterized in that at both ends of the bottom ( 29 ) vertical wall sections of the filter pot ( 11 ), on the one hand pressure-tight on the valve housing ( 3 ), on the other hand pressure medium-tight on the wall of the valve seat receiving body ( 7 ) issue. Electromagnetic valve according to claim 7, characterized in that the vertical wall section Filterele elements in the form of a ring and plate filter ( 31 . 32 ). Electromagnetic valve according to claim 8, characterized in that the plate filter ( 31 ) the check valve ( 10 ) in the bypass bore ( 12 ) by the plate filter ( 31 ) at least in sections, the check valve ( 10 ) covered. Electromagnetic valve according to one of the preceding claims, characterized in that the filter cup ( 11 ) in the region of the projection ( 14 ) a fixed aperture ( 33 ). Electromagnetic valve according to claim 1, characterized in that the filter cup ( 11 ) by plastic injection molding and the check valve ( 10 ) is made as a ball check valve made of a metal.