DE102008064604B4 - Electromagnetically actuated fluid valve - Google Patents

Abstract

Electromagnetically actuated fluid valve, in particular switching valve or proportional valve, with a valve housing (1) and with an actuating magnet arranged on the valve housing (1) with a pole tube (7) which is attached to the valve housing (1) and in which an armature is movably guided is, with a coil (3) which is arranged on the pole tube (7) and which is surrounded by a coil housing (5) made of metallic material, and with fastening means which the coil (3) on the pole tube (7) against axial Secure displacement, wherein connecting means are provided, which produce an electrically conductive connection between the pole tube (7) and the coil housing (5), characterized in that the connecting means comprise a metal ring (11) over the inner radius of the ring projecting contact tabs (12) , where the Coil housing (5) with an annular surface facing him of the metal ring (11) is contacted and the pole tube (7) with the contact tabs (12), which create an outer circumferential surface of the pole tube (7) is contacted.

Description

The invention relates to an electromagnetically operable fluid valve according to the preamble of claim 1. The invention further relates to the connection means specified in more detail in the claims.

The data sheets RD 23178 / 04.05 and RD 23327 / 02.03 describe directional control valves which are switched directly by actuation solenoids. The actuating magnets each comprise a screwed into the valve housing pole tube in which an armature is movably guided, a slipped over the pole tube coil, which is surrounded by a metal housing - also called coil housing - and a fastening nut which is screwed onto a threaded portion at the end portion pole tube is to axially secure the coil on the pole tube. Especially at higher operating voltages of the coils, e.g. 230V AC or 48V, 96V, 110V or 205V DC, it is necessary to provide a grounding of the coil housing. This is done via a separate PE contact on the connector of the coil.

A disadvantage of the conventional solution is the high cost of wiring the coils. If you want to save on a third conductor on the PE connection, so the coil winding must be made in a high isolation quality, which in turn makes the coil more expensive.

The document DE 198 21 498 A1 discloses a control valve for a variable displacement compressor. The control valve has a valve housing and an attached pole tube, in which an armature is movably guided. It also has a coil which is arranged on the pole tube and which is surrounded by a coil housing made of metallic material. The pole tube and the coil housing are electrically connected together.

The document DE 37 37 777 A1 discloses a solenoid valve with a cup-shaped magnet housing and a valve body which is clamped to this housing.

The document DE 10 2004 035 501 A1 discloses a solenoid with adjustable magnetic force, as well as a solenoid valve with such a solenoid.

The document JP H09-119544 A discloses an electromagnetic device for which an iron core is integrally connected to a cylindrical yoke.

The invention is based on the object of specifying a simple to be presented and contact-safe grounding of a coil housing of a magnetic coil of a fluid valve.

This object is achieved by an electromagnetically actuated fluid valve with the features of claim 1.

According to the invention, the earthing of the coil housing is effected by connecting means which produce an electrical connection between the coil housing and the pole tube. The valve housing and the pole tube are already grounded in permanently installed industrial plants. Therefore, the grounding of the bobbin case can be made safe in this way easily and with little effort. The grounding of the coil housing also allows to use more isolated coils, which can be made cheaper, if necessary. The invention can be used in particular in electromagnetically operated directional control valves, pressure valves or flow valves. In particular, the invention is advantageous for switching valves in which a high switching voltage is used. However, it can also be used with proportional valves.

According to the invention, it is further provided that the connecting means comprise a metal ring with contact lugs projecting beyond the inner radius of the ring, wherein the coil housing is contacted with an annular surface of the metal ring facing it and the pole tube is contacted with the contact lug, which bears against an outer circumferential surface of the pole tube ,

Advantageous developments of the present invention are the subject of the dependent claims. The connecting means mentioned therein are also considered on their own as the subject of this patent application.

Hereinafter, the present invention and its advantages will be explained in more detail with reference to the embodiment shown in the figures.

• 1 represents a fluid valve in which an electrical connection between pole tube and coil housing is made via a metallic nut,
• 2 represents a contact ring, which is used instead of the metallic nut for forming the said electrical connection, and
• 3 shows a fastening nut made of plastic for screwing onto the pole tube, in which an electrical conductor is cast.

In 1 a valve for hydraulic applications including an actuating magnet is shown schematically. On the valve housing 1 is a pole tube 7 screwed into a valve hole. In the pole tube, an anchor is movably guided. The armature transmits the actuating force by means of a plunger to a valve piston arranged in the valve housing 1. On the pole tube 7 a solenoid 3 is pushed. In addition to the actual coil winding and the associated sheath has the magnetic coil 3 a coil housing 5, which is made of metal and which surrounds the coil winding for protection against external influences.

According to a non-inventive embodiment, a nut 9, which consists at least partially of metal on the pole tube 7 on the side of the valve housing 1 screwed. This nut 9 provides an electrical connection between the coil housing via its internal thread and an end-face contact surface 5 and the pole tube 7 ago. The mother 9 can be made of sufficiently conductive metal. The mother 9 However, it can also consist of a plastic in which metal particles are embedded with a high degree of filling.

Based 2 An embodiment of the invention will be described. Shown is a metal ring 11 , which at least one notched tab 12 has. The tab 12 is sized so that it extends radially beyond the inner diameter of the metal ring 11 protruding inwards. This metal ring 11 is pushed onto the pole tube after pushing the solenoid 3. The coil housing 5 becomes with the ring-facing ring surface of the metal ring 11 contacted. The pole tube 7 is by means of the tab 12 , which applies to the outer circumferential surface, contacted.

Subsequently, a fastening nut made of plastic can be screwed onto the pole tube 7. The said fastening nut has the shape of the metal ring 11 corresponding recesses. Furthermore, sealing rings may be provided to prevent exposure of moisture to the contact points.

The metal ring 11 can on its the bobbin case 5 facing thorn-like projections have. These penetrate when pressing the metal ring 11 to the coil housing 5 a possibly existing lacquer layer or oxide layer and thus produce a secure electrical connection. The pressing can be done by tightening said plastic nut.

Another non-inventive embodiment is by means of 3 explained. Instead of the predominantly metal existing nut 9 or instead of the metal ring 11 a plastic nut 14 on the pole tube 7 behind the magnetic coil 3 screwed. In the plastic nut 14 an electrical conductor 16 is cast. The leader 16 is with two contact surfaces 18 and 20 electrically connected. The contact surface 18 is at the bobbin case 5 facing end face of the plastic nut 14 arranged. The contact surface 20 occurs on an inner circumferential surface of the plastic nut 14 out. The contact surface 20 can be inside or outside of a female thread section 22 the plastic nut 14 may be arranged. The contact surfaces 18 and 20 can also emerge slightly from the surface of the surrounding plastic material to allow a secure contact. The contact surfaces 18 and 20 may be part of the conductor 16 be. Among other things, they may be in the form of a circular ring, a circular line, partial sectional shapes thereof, the shape of a point contact, rectangular surfaces, thorns, etc.

An electromagnetically operable fluid valve is equipped with a valve housing, an actuating magnet arranged on the valve housing with a pole tube, which is attached to the valve housing and in which an armature is movably guided, with a coil which is arranged on the pole tube and which of a coil housing of metallic material is surrounded, and with fastening means which secure the coil on the pole tube against axial displacement. It is a metal ring, which has at least one notched tab provided as a connecting means, which produces an electrically conductive connection between the pole tube and the coil housing.

In this way, the grounding of the bobbin case can be made easily and easily with little effort.

LIST OF REFERENCE NUMBERS

1

valve housing

3

solenoid

5

coil housing

7

pole tube

9

metal nut

11

contact ring

12

flap

14

Plastic nut

16

ladder

18

contact area

20

contact area

22

Internally threaded portion

Claims (10)

Electromagnetically actuated fluid valve, in particular switching valve or proportional valve, with a valve housing (1) and with an actuating magnet arranged on the valve housing (1) with a pole tube (7) which is attached to the valve housing (1) and in which an armature is movably guided is, with a coil (3) which is arranged on the pole tube (7) and which is surrounded by a coil housing (5) made of metallic material, and with fastening means which the coil (3) on the pole tube (7) against axial Secure displacement, wherein connecting means are provided, which produce an electrically conductive connection between the pole tube (7) and the coil housing (5), characterized in that the connecting means comprise a metal ring (11) with over the inner radius of the ring protruding contact tabs (12) , wherein the coil housing (5) is contacted with an annular surface facing the metal ring (11) and the pole tube (7) with the Contact tabs (12), which create an outer circumferential surface of the pole tube (7), is contacted. Fluid valve after Claim 1 , characterized in that the connecting means are provided in the region of the fastening means. Fluid valve after Claim 1 or 2 , characterized in that the connecting means comprise a wholly or at least partially made of metal screw nut (9). Fluid valve after Claim 3 , characterized in that the screw nut (9) also serves as a fastening means. Fluid valve according to one of the preceding claims, characterized in that the connecting means have a radially - in particular resiliently - to the pole tube (7) can be applied first contact element (12; 20). Fluid valve according to one of the preceding claims, characterized in that the connecting means have an axially - in particular spring-elastic - to the coil housing (5) can be applied second contact element (18). Fluid valve after Claim 5 or 6 , characterized in that the electrical connection produced by the first contact element (12; 20) or the electrical connection produced by the second contact element (18) are protected from corrosion by sealing means. Fluid valve according to one of the preceding claims, characterized in that the connecting means comprise a metallic spring washer or a metal spring washer. Fluid valve according to one of the preceding claims, characterized in that the fastening means comprise a substantially made of plastic plastic nut (14) and that the connecting means comprise an inserted or injected into the plastic nut (14) electrical conductor (16). Fluid valve after Claim 9 , characterized in that on one of the coil housing (5) facing the end of the plastic nut (14) and on an inner circumferential surface of the plastic nut (14) in each case one with the electrical conductor (16) connected contact surface (18, 20) is provided.

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