EP2621026A1 - Sealed plug method for sealing a plug - Google Patents

Abstract

The connector has a connector main portion (1) whose bottom portion (10) is passed through a conducting path (12). A passage of the conducting path is sealed with a silicon adhesive (26) e.g. acetoxy adhesive. A gap is formed between the conducting path and the bottom portion of the main portion. A coil winding (34) is arranged at the main portion. Independent claims are included for the following: (1) a hydraulic aggregate housing; and (2) a method for sealing passage of conducting path.

Description

The invention relates to a sealed plug according to the preamble of patent claim 1 and a method for sealing a plug according to the preamble of patent claim 13.

Control elements of the hydraulic system, such as valves, can be actuated electromagnetically. For this purpose, the valve has an encapsulated electromagnet with a coil, via the energization of which an armature is moved, which carries a valve piston. In this way, a position of the valve piston can be precisely adjusted. To power the coil, a housing passing through the plug is provided on the housing of the electromagnet, which preferably consists of plastic and molded onto the housing. With a current source connectable current paths or pins of the plug pass through a plug bottom of the plug from an outside to an inside of the housing, where they are connected to the coil.

It is known to pour the plug bottom of the plug with a dielectric sealant to seal the passage of the current paths against moisture penetration. Here conventionally plastics, epoxy resin or silicone rubber are used.

The design text DE 1 148 613 from 1963 recommends as sealing compound for the plug to be cast silicone, which should have the tendency to adhere to the touched materials. Alternatively, sticky petroleum compounds or rubber or epoxy compounds are suggested.

A disadvantage of the proposed solutions is that the substances proposed as sealant materials are not specified. A disadvantage of the proposed epoxy compounds is that they are subject to shrinkage, in particular during thermal cycling, which can lead to a separation and thus to leakage at a boundary layer between pin and sealant.

The patent DE 44 10 455 C1 From 1995, the recommendation for the use of an adhesive silicone and refers to the use of a 2-component UV-curing silicone. However, the patent advises against this concept, since under mechanical stress of the silicone, in particular during a movement of the pins or pins, an adhesion of the silicone lost. Instead, a solution is proposed in which the tightness is achieved by a special geometric configuration of the pins and a shrinkage of the plastic surrounding the pins during its cooling in the manufacturing process.

A disadvantage of the solution without sealant is that the plastic surrounding the pins is subject to shrinkage over its lifetime. In addition, the plastic is only slightly elastic, so that it can come in this solution for recurring mechanical stress or thermal cycling to the leakage of the passage.

In contrast, the invention has the object to provide a plug with an improved tightness against ingress of moisture.

This object is achieved by a sealed plug with the features of patent claim 1, and by a method for sealing a plug with the features of claim 13.

Advantageous developments of the invention are described in the dependent claims.

The plug according to the invention for the electrical supply of an aggregate of the hydraulic system can be arranged on a housing of this unit. In this case, a plug base of the plug is penetrated by at least one current path. This passage of the at least one flow path through the plug base is sealed with a silicone-containing compound. According to the invention, this mass is an adhesive, and has a high adhesion. This strong adhesion can ensure that under adverse operating conditions in which the current path is moved, the sealing mass still adheres to the current path. A detachment from the flow path, i. a gap formation between the flow path and the sealant is thus prevented. This allows the unit to be permanently sealed against moisture. In connection with the high adhesiveness of the mass or the adhesive is preferred when the adhesive has a high flexibility. In this way, the adhesion of the adhesive to the current path is further improved. Another advantage of the adhesive used is that at a thermal cycling of the connector, which leads to stresses in the boundary layer between Stormbahn and adhesive due to different thermal expansion coefficients of the sealant or the adhesive and the current path, the tightness of the plug is still maintained.

Plug base is understood to be a region of a housing of the plug through which a current path passes.

The unit is preferably connected via the plug with a power source or an electrical control unit. Particularly preferably, the unit is a coil of an electromagnet or a control cabinet. It is preferred if via the solenoid, a valve, in particular a pilot valve of the mobile hydraulics, can be actuated.

In an advantageous development of the plug, the plug base of the plug is filled with the adhesive at least in a region of the passage of the at least one flow path. The pouring is manufacturing technology little expensive, so that the seal is inexpensive to produce.

For plugs that have coarse manufacturing tolerances and therefore have a gap arranged between the at least one flow path and the plug bottom, in particular an annular gap or a gap, the silicone-containing adhesive proves to be very advantageous, since due to its low surface energy in a very narrow Gap penetrates, so that it is sealingly filled with the adhesive or filled.

In a particularly preferred embodiment of the plug, the adhesive is one-component, which represents a reduction of the expense compared to a use of two- or multi-component adhesives or adhesives with catalyst.

Particularly suitable for this purpose is an acetoxy adhesive which, at least in the uncured state, has an acetoxy group.

In a particularly preferred variant of the adhesive, it is light-cured, in particular UV-light-cured. Alternatively or additionally, the adhesive may be moisture cured. Particularly preferably, the adhesive is primarily light-cured or UV-light-cured and secondarily moisture-cured.

In a preferred variant of the plug, the adhesive is in a region near the plug bottom, i. near the passage of the current path through the plug base or the plug housing, tough or viscous. As a result, the sealing adhesive has a higher elasticity and is also more adhesive. These properties can be achieved, for example, by the adhesive in this area is not fully cured.

In a particularly advantageous development of the plug, an insulation resistance via the sealed passage of the at least one current path at an applied voltage of 500 volts has a value greater than 0.5 MIO (megohms). This value is particularly preferably about 1 MΩ.

In a particularly advantageous embodiment of the plug, a coil winding is arranged on this, so that a device-particularly compact and space-saving arrangement of a coil of an electromagnet is possible.

It proves to be particularly advantageous when the plug according to the invention is arranged, in particular molded, on a housing of an aggregate of the hydraulic system for the electrical supply of the unit.

In this case, the unit is preferably a coil of an electromagnet or a control cabinet, wherein via the solenoid preferably a valve, in particular a pilot valve of the mobile hydraulics can be actuated. Particularly advantageous is the use of the housing in the mobile hydraulics, when the housing is exposed to changing operating conditions over water and especially under water. This applies, for example, to mobile working machines that are used in flood protection to rescue people. It may happen that electrically or electrohydraulically actuated valves or their electromagnets get under water. The tightness of their plugs for power supply is crucial.

A method according to the invention for sealing a plug bottom of a plug which is penetrated by at least one current path, or for sealing a passage of the at least one current path through the plug base, wherein an aggregate of the hydraulics can be supplied electrically via the plug, comprises the step of: sealing the passage with a plug silicone-containing adhesive. In this case, the sealing is preferably carried out by filling a gap formed in a region of the passage between the at least one flow path and the plug base. This gap may be formed in particular as a gap or as an annular gap. The sealing or the filling can be done in particular by pouring the plug base with the silicone-containing adhesive in the region of the passage of the at least one current path through the plug base.

Due to the strong adhesion of the adhesive, in particular to the flow path and a surface of the plug base or of the passage, it can be ensured that under disadvantageous operating conditions in which the flow path is moved, the sealing mass of the adhesive still adheres to the flow path. A detachment of the adhesive from the flow path, or a gap formation between the flow path and the sealant, is thus prevented. As a result, the unit can be permanently sealed in the area of the current path against ingress of moisture. In conjunction with the high adhesiveness of the adhesive, it is preferred if the adhesive has high flexibility or elasticity. In this way, the adhesion of the adhesive to the current path is further improved. Another advantage of the adhesive used is that at a thermal cycling of the plug, which leads to stresses in the region of the boundary layer between the current path and adhesive due to different thermal expansion coefficients of the sealant or the adhesive and the current path, the tightness of the plug is still maintained.

It is advantageous to use silicones as an adhesive, since they have a low surface energy in the liquid state and can therefore very well wet the plug base to be sealed and the current path to be sealed. The casting of the plug base of the plug is a procedurally well controllable step. However, it must be ensured that the components to be glued or sealed the current path and the plug base are clean. The silicone-containing adhesive is preferably one-component in order to keep the procedural effort low. In this case, the adhesive preferably has an acetoxy group.

It is particularly advantageous if after sealing the passage of the at least one current path through the plug base with the silicone-containing adhesive as a further step, the silicone-containing adhesive is cured by light, in particular by ultraviolet light.

Alternatively or additionally, the method according to the invention, after or during the step of curing the silicone-containing adhesive by light as a further step, a curing of the silicone-containing adhesive by moisture, in particular by humidity or water vapor, on. This ensures that areas that are not accessible or accessible during curing with light, harden by the naturally occurring in the ambient air humidity.

• Fig. 1 einen Stecker in einer Vorderansicht;
• Figur 2 den Stecker gemäß Figur 1 in einem Längsschnitt;
• Figur 3 u. 4 den Stecker gemäß Figur 1 und 2 mit einer Vorrichtung zum Einbringen des Klebers; und
• Figur 5 u. 6 den Stecker gemäß Figur 1 und 2 mit einer Vorrichtung zum Aushärten des Klebers.

In the following, an embodiment of a plug according to the invention will be explained in more detail with reference to FIGS. It shows:

• Fig. 1 a plug in a front view;
• FIG. 2 according to the plug FIG. 1 in a longitudinal section;
• FIG. 3 u. 4 the plug according to FIGS. 1 and 2 with a device for introducing the adhesive; and
• FIG. 5 u. 6 the plug according to FIGS. 1 and 2 with a device for curing the adhesive.

FIG. 1 shows a plug 1 for powering a coil of an electromagnet (not shown), via which a pilot valve of the mobile hydraulics can be controlled in a front view. The plug 1 is made of plastic as an injection molded part. It has a substantially circular cylindrical plug housing 2, which is provided for arrangement in a corresponding outbreak of a housing of the electromagnet (not shown). The connector housing 2 has an end face 4, from which, the viewer of the FIG. 1 opposite, a connector device 6 extends. The connector device 6 has an approximately rectangular connector collar 8 with rounded corners. In the region of the plug base 10, two current paths 12 configured as pins and four smaller spacers 14 are symmetrical to a vertical axis 16 of the plug 1 arranged. Above a transverse axis 18 which extends through centers of the two current paths 12, a Verrastungsträger 20 is arranged on the plug collar 8. The Verrastungsträger 20 has at its in FIG. 1 lower, open side on a guide groove 22, which on both sides to the vertical axis 16 in the direction of a FIG. 1 upper side of the plug 1 is further recessed, and in this way forms a Verrastungsnut 24. The plug base 10 of the plug 1 is in this case filled with an adhesive 26, that the spacers 14 and the current paths 12 are each connected to its radially outer surface cohesively with the adhesive 26.

FIG. 2 shows the embodiment of the plug according to FIG. 1 in a longitudinal section.

The plug 1 extends in FIG. 2 from the plug collar 8 right to the left-side connector housing 2. Approximately in the middle between the plug base 10 is arranged. Radially circumferentially on the plug base 10, an O-ring groove 28 is formed, which is provided for receiving an O-ring or sealing ring (not shown). The plug 1 is in a built-in state, ie when it is attached to a housing of the coil or the electromagnet (not shown), arranged at the level of the plug base 10 or at the level of the O-ring groove 28 on the housing. About the O-ring, the housing with the connector 1 waterproof or moisture-proof sealed.

The two current paths 12 pass through the plug 1 or its plug base 10 in FIG FIG. 2 from right to left. With a in FIG. 2 not shown left end portion of the current paths 12 dip this in a winding body 30 a. This winding body 30 has a winding groove 32 which opens radially outwards and into which a coil winding 34 is accommodated. This coil winding 34 is connected to the end portions of the current paths 12, which are pressed into the plastic of the winding body 30, or contacted by these. Via the current paths 12, a power supply of the coil winding 37 is thus produced.

Radially inside the connector housing 2, a pole plate 36 is arranged, which serves as a magnetic return plate for closing the magnetic circuit.

In FIG. 2 right above is the Verrastungsträger 20, via which a plug of the power source (not shown) with the plug 1 and the connector device 6 is detachably connected, arranged. The plug of the power source must be approximately coaxially inserted into a framed by the plug collar 8 connector receptacle 44. This takes place until one end of the plug, not shown, comes into abutment with the spacers 14 of the plug 1. The spacers 14 of the plug 1 are elastically deformable in the axial direction, so that the plug, not shown, can continue to penetrate further or deeper into the plug receptacle 44 by the application of a certain force. In conjunction with a Verrastungsnase the connector, not shown, the latching takes place when the Verrastungsnase engages behind a Verrastungskante 38 Verrastungsausnehmung 40 of Verrastungsträgers 20. In this way, the plug, not shown, with a certain bias in the connector receptacle 44 can be fixed. For example, in radial movements of the plug, not shown, it may come to a transverse movement of the current paths 12 due to transmitted to the current paths 12 transverse forces. In order to limit this movement of the current paths 12, the plug base 10 of the plug 1 is in FIG. 2 extended to the right by a base rib 42. This has the task to clamp the penetrating current paths 12. Thus, a movement of the current paths 12 is prevented to a certain extent.

To prevent from the outside (in FIG. 2 Right) acting moisture, such as water or water vapor, from the connector receptacle 44 passes through the spaced by the current paths 12 plug bottom 10 toward the coil winding 34, the plug-in collar 8 encompassed plug base 10 is filled with a silicone-containing adhesive 26. This is a single-component acetoxy silicone adhesive LOCTITE ^® 5091 ^™ (Technical Data Sheet December 2007). The one-component mold proves to be advantageous during the filling of the plug base 10, since no mixing with a second Component or with a catalyst is required. A curing of the adhesive 26 takes place during the manufacturing process or after filling by UV light. Already under normal processing conditions, the adhesive 26 is exposed to sufficient UV radiation to completely cure at least on the surface. In this case, the adhesive 26 has a further positive and advantageous property, since it cures by surface or atmospheric moisture even in shadow areas into which no UV radiation can get. A complete cure of the adhesive is achieved after about 72 hours at ambient temperature. The adhesive used 26 is highly flexible, whereby the splice has a shock-absorbing property and a good load capacity. A transverse movement of the current paths 12 can be well compensated not only because of the adhesion of the adhesive 26, but also due to the elasticity of the adhesive 26. At the interfaces between the current paths 12 and the adhesive 26 so a gap formation is effectively prevented.

In the FIGS. 3 and 4 schematically a preferably designed as dosing tip dosing device 50 for the metered and precisely placed introduction of the liquid adhesive 26 in the passage region of the current paths 12 in the region of the plug base 10 is shown. The metering device 50 is thereby introduced with respect to their position in the region of the connector receptacle 44, that due to the amount and the flow properties of the adhesive 26 is a uniform filling of the gap in the passage region of the current paths 12 and to the outside a homogeneous smooth surface of the adhesive 26th formed.

In the FIGS. 5 and 6 FIG. 2 schematically illustrates a curing device 51, preferably designed as a UV light source, for curing the liquid adhesive 26. By a suitable metered energy supply to the curing device 51, the formation of a homogeneous outer surface of the adhesive 26 is supported so that the area filled in by the adhesive 26 perfectly seals the plug 1 also to the outside and does not form any gaps for later entry of water during operation.

Not only in the discussed mechanical loads but also in a thermal cycling of the connector 1, the adhesive used 26 has advantageous and positive properties. This is shown by stress tests, which have the task of investigating the tightness of the passage of the current paths 12 through the plug base 10. The heated by a two-hour storage in a climatic chamber at 140 ° C plug 1 are suddenly immersed in 20 ° cold water. There they remained at one meter depth for a period of one hour. In a subsequent storage of the specimens in a climatic chamber and at 20 ° was examined to what extent water has come from the plug receptacle 44 to the other side of the plug 1 in the region of the winding body 30. Even after 20 cycles, no leaks occurred. An insulation resistance of the sealing adhesive 26 was greater than 1 MΩ in each case. A leakage current was less than 10 μA at an applied voltage of 500 volts.

Notwithstanding the use of the plug 1 for a coil of an electromagnet of a pilot valve of the mobile hydraulics plug 1 according to the invention can be used with advantage everywhere where a watertight implementation of electrical current paths or pins is required. The plug according to the invention proves to be particularly advantageous when used on pilot valves for mobile control blocks. In contrast to conventionally cast floors of plugs that are sealed with epoxy resin or Siloprenmasse, the plug according to the invention has significantly better properties of the seal with temperature changes and mechanical stress.

Disclosed is a plug for the electrical supply of an aggregate of the hydraulic, which can be arranged or arranged on a housing of such an aggregate. A plug base of the plug is penetrated by a current path and sealed in a region of this passage with a silicone-containing compound against moisture penetration. According to the invention, this composition is an adhesive with high adhesion forces.

Furthermore, a housing of an aggregate of the hydraulic system with such a plug is disclosed.

Furthermore, a method is disclosed for sealing a plug-in base of a plug which is penetrated by a current path and via which an aggregate of the hydraulics can be supplied electrically. According to the invention, the method has a step "sealing a passage of the current path through the plug base with a silicone-containing adhesive" on.

LIST OF REFERENCE NUMBERS

1

plug

2

plug housing

4

face

6

plug device

8th

plug collar

10

plug ground

12

current path

14

spacer

16

vertical axis

18

transverse axis

20

Verrastungsträger

22

guide

24

locking groove

26

adhesive

28

O-ring groove

30

bobbin

32

winding groove

34

coil winding

36

pole disk

38

latching edge

40

latching

42

base rib

44

plug receptacle

50

metering

51

curing

Claims (15)

Plug for the electrical supply of an aggregate of hydraulics, which can be arranged on a housing of the unit, wherein a plug base (10) of the plug (1) of at least one flow path (12) is penetrated and a passage of at least one flow path (12) with a is sealed silicone mass, characterized in that the mass is an adhesive (26). Plug according to claim 1, wherein the plug base (10) at least in a region of the passage of the at least one flow path (12) with the adhesive (26) is poured out. Plug according to claim 1 or 2, wherein between the at least one flow path (12) and the plug base (10) arranged gap with the adhesive (26) is poured out. Plug according to one of claims 1 to 3, wherein the adhesive (26) is one-component. Plug according to one of the preceding claims, wherein the adhesive (26) is an acetoxy adhesive. Plug according to one of the preceding claims, wherein the adhesive (26) is light-cured and / or moisture-cured. Plug according to one of the preceding claims, wherein the adhesive (26) in a region near the plug bottom (10) is tough or viscous. Plug according to one of the preceding claims, wherein an insulation resistance across the sealed passage of the at least one current path (12) is greater than 0.5 megohms (0.5 MΩ). Plug according to one of the preceding claims, wherein the unit is a coil of an electromagnet or a control cabinet. Plug according to claim 9, wherein via the solenoid, a valve is actuated. Plug according to one of the preceding claims, wherein a coil winding (34) on the plug (1) is arranged. Housing of an aggregate of the hydraulic system, on which the plug (1) according to one of the preceding claims is arranged. Method for sealing a passage of at least one flow path (12) through a plug base (10) of a plug (1), wherein an aggregate of the hydraulics can be supplied electrically via the plug (1), characterized by a step - Sealing of the passage with a silicone-containing adhesive (26). The method of claim 13, wherein after the sealing of the passage with the silicone-containing adhesive (26), a step - Curing of the silicone-containing adhesive (26) by light he follows. The method of claim 14, wherein after or during the curing of the silicone-containing adhesive (26) by light, a step - Curing of the silicone-containing adhesive (26) by moisture he follows.

Images