DE102012016833A1 - Valve for flowable media, in particular glue valve, and method for producing the valve - Google Patents

Abstract

The invention relates to a valve for flowable media, in particular glue valve, with at least one electromagnet with which a closure element (19) of the valve (10) can be moved and with which heat can be transferred in a targeted manner to the flowable medium, preferably hot glue, the at least an electromagnet has at least one coil (14) which is arranged on a coil carrier (15) which at least partially surrounds the closure member (19). The invention is characterized in that the entire coil carrier (19), but at least the area (16) of the coil carrier (15) on which the turns of the coil (14) are directly adjacent, is made of an injection-moldable, ceramic material with a high thermal conductivity of at least 15 Wm-1K-1, particularly preferably of silicon nitride. The invention also relates to a method for producing such a valve.

Description

The invention relates to a valve for flowable media, in particular a glue valve, with the features of the preamble of claim 1. Furthermore, the invention relates to a method for producing such (glue) valves having the features of the preamble of claim 10.

A glue valve with the aforementioned features is for example in the DE 10 2010 034 761 shown and described. A closure member, namely a valve stem, is in this case surrounded by two (electric) coils, which are arranged on a common coil carrier or bobbin. The unit of coils and bobbin is housed in a valve housing. The coil carrier consists of high quality plastic with fiber reinforcement. Each coil is part of one of a total of two electromagnets, with which the closure member is movable. The waste heat of the coils is selectively transferred to the (hot) glue inside the valve chamber.

It is an object of the present invention to further develop such glue valves. The same applies to the production of such glue valves.

To achieve this object, the valve according to the invention has the features of claim 1. A method of manufacturing such a valve is described by the features of claim 10.

A special feature of the valve according to the invention therefore consists in that the entire coil carrier, but at least the region of the coil carrier, against which the turns of the at least one coil directly abut, made of an injection-moldable, ceramic material having a high thermal conductivity of at least 15 Wm ^-1 K ^{- 1} exists. It has surprisingly been found that the use of such a ceramic material is associated with particular advantages.

On the one hand, the ceramic material of such high thermal conductivity ensures that the thermal energy generated by the at least one coil of the electromagnet is passed on particularly well during operation and transferred to the flowable medium. At the same time it is ensured by the use of ceramic that the coil carrier is an electrical insulator, so that the turns of the at least one coil can be wound directly onto the bobbin without the risk of electrical short circuits. Furthermore, by virtue of the selected ceramic being injection-moldable, it is possible to produce the coil carriers inexpensively by means of conventional injection molding methods. The temperature resistance of ceramics finally ensures a long service life.

According to a further special feature of the invention, the coil carrier is arranged in a housing chamber or in an interior of the valve, between at least one of the housing chamber adjacent housing chamber wall and the at least one coil and / or the coil carrier initially during assembly of the valve, a free space is available , which is filled before the completion of the valve with a thermally conductive potting compound.

In this case, the potting compound comes into contact, in particular, with the outside of the at least one coil running parallel to the coil axis, and then preferably penetrates further inwards through spaces / channels between the turns of the at least one coil in the direction of the coil axis, in particular to the coil carrier.

The potting compound ensures a particularly good distribution of the resulting heat. Local heat peaks are avoided. As a result, a uniform heat transfer to the flowable medium is possible. In this case, the potting compound preferably has a thermal conductivity value between 0.5 Wm ^-1 K ^-1 and 2.0 Wm ^-1 K ^-1 . As a potting compound, for example, a crosslinked organic polymer may be used, for example, one or more epoxides.

In a further embodiment of the invention, the valve preferably has two detachably interconnected or connectable modules, namely a valve unit in which, inter alia, the closure member, the at least one coil and the coil carrier are arranged, and a supply unit, in which at least one connection for a supply line for the flowable medium is arranged, in particular for a hose, and a supply for power and / or control lines.

The valve unit preferably has a plug part, from which current and / or control lines are led to at least one electrical component of the valve unit, preferably to the at least one coil. The plug part is then plugged in the assembly of the valve in a matching plug part of the supply unit, are guided by the power and / or control lines to the supply of the supply unit.

In the context of the method according to the invention for producing a valve described above, the coil carrier is preferably first injection molded from the injection-moldable, ceramic material with the high thermal conductivity. Subsequently, the at least one coil of the Electromagnet wound on the injection-molded coil carrier.

During assembly of the individual valve components necessary for the valve, the coil carrier together with the at least one coil is then arranged in the above-mentioned valve housing chamber.

Via a filling channel, which is guided from the valve housing chamber to the outside of an (outer) wall of the valve housing, the space described above between the at least one, the valve housing chamber bounding chamber wall and the at least one coil and / or the coil carrier from the outside filled with potting compound.

Preferably, the filled unit is spent after the filling under vacuum in order to outgas any air pockets in the potting compound. Such air influences would hinder the heat transfer in the potting compound and thus the heat distribution.

Further features of the present invention will become apparent from the appended claims, the following description of a preferred embodiment of the invention, as well as from the accompanying drawings. It shows:

1 a top view of an inventive, ready-mounted glue valve with valve unit and supply unit,

2 a vertical section through the glue valve 1 along the section line II-II,

three the valve unit as shown 2 in a phase before the completion of the valve,

4 a section along the section line IV-IV 1 ,

The glue valve shown in the drawings 10 is preferably used to transfer relatively small sized glue portions to fold flaps of packages, such as cigarette packs. It is designed for high cycle rates.

The glue valve 10 comprises a valve unit 11 with a valve housing 11a as well as a supply unit 12 with supply housing 12a , valve unit 11 and supply unit 12 are. by fastening the valve housing 11a on the supply housing 12a connected with each other.

Inside the valve housing 11a , namely in a valve housing interior or a valve housing chamber 13 , in the present case are two coils 14 arranged two electromagnets. Each electromagnet has one coil each 14 , In principle, only one electromagnet with one or more coils or more than two electromagnets with one or more coils could be used.

The two coils 14 Both are in the present embodiment, both on a common bobbin or bobbin 15 wound. They are not shown separately or individually.

The coil carrier 15 In this case, it is in the area in which the windings of the coils 14 are arranged, via a tubular or hollow cylindrical portion 16 with correspondingly cylindrical outside 17 ,

The hollow cylindrical section 16 of the bobbin 15 surrounds a corresponding cylindrical interior 18 , Inside the interior 18 is a closure or metering organ 19 of the valve 10 movably arranged, namely a valve tappet.

On a lower shaft 20 of the closure member 19 is a ball 21 as a closure means for a metering or valve opening 22 attached. The valve opening 22 is centered in the area of a funnel-shaped valve seat or in the region of a valve nozzle 23 arranged. The ball 21 lies in the in 2 shown closed position of the valve 10 on conical seating surfaces of the valve nozzle 23 and closes the valve opening 22 ,

About one on the supply housing 12a arranged as a hose connection 24 trained glue connection of the supply unit 12 can the glue valve 10 glue to be metered, in the present case hot glue, over a heated hose 25 be supplied from a glue source, not shown.

From the hose connection 24 the glue gets in the supply case 12a along a first glue channel 26 of the glue valve 10 first via a filter 27 guided. After flowing through the filter 27 the glue is over a second glue channel 28 in the valve body 11a passed and flows from there into from the coil carrier 15 surrounded interior 18 of the valve 10 and then towards the nozzle 23 or valve opening 22 ,

The one from the valve nozzle 23 inside limited space forms together with the interior 18 and adjacent connecting areas, the actual valve chamber of the valve 10 in which the glue to be applied is located during operation.

The closing organ 19 is opened by applying a suitable current to the electromagnets, so that glue over the valve opening 22 can escape from the valve chamber.

For this purpose, they are surrounded by the common coil carrier 15 arranged coils 14 the electromagnet the closure member 19 at least in sections. The present is above the shaft 20 of the closure member 19 in the area of the coil carrier 15 as well as the coils 14 surrounded interior 18 one with the valve body 20 connected, metallic guide piece 29 of the closure member 19 arranged.

The metallic guide piece 29 acts within the coils 14 as the core of the electromagnets of the valve 10 , In a suitable, later described in more detail power supply to the coils 14 , These transfer a resulting magnetic force or an opening force on the guide piece 29 , As a result, the closure member 19 , and with it the bullet 21 , total from the in 1 shown closed position in a the valve opening 22 releasing opening position moves, in which the glue from the valve opening 22 can escape.

The closing organ 19 is in the closed position preferably permanently acted upon in the closing direction by a closing means or closing member. This is formed in the present embodiment as a permanent magnet comprising two repulsive individual magnets (not shown), which has a permanent, resulting magnetic force on the closure member 19 exercises in the sense of a closing movement. Of course, other suitable closing forces exerting closing means may be used, such as (backyard) springs or the like.

The one single magnet of the permanent magnet is fixed to the valve housing 11a connected. In the present case, this single magnet is for this purpose in the lower end of a bolt-like magnet holder 30 attached, in a suitable recess in the region of the guide piece 29 facing end surface. The bolt-like magnet holder 30 again has an upper threaded approach 35 that with one in a thread 46 on the valve body 11a screwed counter nut 38 is bolted and in this way firmly with the valve body 11a connected is. The thread approach 35 has a suitable adjusting recess, such as a (inner) hexagonal recess, or a suitable positioning approach. With an appropriately adjusted adjusting tool, such as a matching (internal) hex key, then the axial position or the height of the threaded neck 35 and with it the entire magnet holder 30 be set. Accordingly, the valve lift is adjusted or adjusted in this way.

The other single magnet of the permanent magnet is opposite to the closure member 19 attached, in a recess on the bolt-like magnet holder 30 facing end surface of the guide piece 29 , The individual magnets have a (small) distance from each other even when the glue valve is open.

The two individual magnets are positioned so that the same poles face each other, for example the north pole. Due to the repulsive force between the permanent individual magnets is permanently a repulsive force on the closure member 19 transferred so that it is acted upon in the closed position with a corresponding closing force.

The opening force caused by the previously described electromagnets acting on the closure member 19 or the guide piece 29 acts, then overcomes this permanent closing force.

The windings of the coils or the windings are - as already mentioned - on the bobbin 17 or on the hollow cylindrical section 16 the same wound up. In the present case follow in the vertical or in the axial direction of the bobbin 17 alternating turns of a coil 14 and turns of the other coil 14 each other. The turns are in the first winding position, in which the individual turns directly on the bobbin 17 abut, and in all other, following in the radial direction Windungslagen each alternately (relative to the axial direction) side by side. The type of winding or the arrangement of the two coils 14 but can also be done differently. The important thing is the coils 14 so on the common coil carrier 15 aufwickeln that in operation, the effects described in more detail below can be achieved.

Both electromagnets or both coils 14 During operation, they are either supplied with current in the same direction or with current in the opposite direction. In this case, the current intensities are preferably identical in absolute terms in each case.

By current application with current of opposite direction produce the coils described in the above or equivalently arranged 14 in the coil inside or in of the coil carrier 15 surrounded interior 18 preferably equally strong magnetic fields in opposite axial directions.

In other words, the magnetic fields of the two electromagnets lift inside the coils 14 on. On the leader 29 or that closure member 19 Accordingly, no magnetic forces are exerted by the electromagnets in this type of current application, so that the closure member 19 remains in its closed position caused by the individual permanent magnets.

The current is generated by the coils 14 However, heat, which in the interior 18 is delivered glue and serves to heat the same.

When current is applied to the same direction, the electromagnets generate magnetic fields in the same direction, so that the guide piece 29 a resultant magnetic force (opening force) is applied, which counteracts the closing force exerted by the individual magnets and for movement of the closure member 19 leads into the open position.

The electromagnets or the coils 14 Accordingly, in the present case are designed such that these in the operation of the valve - both in the opening movement of the closure member 19 as well as during the closing movement of the closure member or in the closed state of the valve 10 - Generate and release heat, which is used to heat up the valve 10 Guided glue is suitable.

Accordingly, the glue valve 10 so-called hot glue can be supplied in the valve 10 can be (further) heated or heated or kept at temperature by the heat coming from the electromagnets.

The electromagnets thus fulfill a dual function in this embodiment of the invention. Through them, on the one hand, the closure member 20 On the other hand heat is given off to the usually already preheated hot glue.

What the supply unit 11 of the valve 10 concerns, so lead to the supply housing 12a via a cable feed 31 several power supply lines and several control lines 32 , The the coils 14 power lines 32 end up on a plug 30a , This is with the supply housing 12a via a plug holder 33 on which he is situated in the present case.

The plug 30a is with a matching mating connector 30b the valve unit 11 connected. The mating connector 30b is with the valve body 11a over tight connector holder 33b connected.

From the plug 30b go corresponding power lines 34 off, with the coils 14 are connected.

Other lines 32 are with separate, in recesses of the supply housing 12a sitting heating cartridges 44 connected to the heating of primarily the housing 12a the supply unit 12 serve to keep the glue liquid or not to let it cool too much while passing through the supply unit 12 flows.

In particular, they serve together with the heat generating electromagnets or coils 14 to shorten the heating times in which before the actual start-up of the valve ( 10 ) the valve ( 10 ) must be brought to working temperature. To monitor the housing or the conductor temperature is further in a corresponding recess of the supply housing 12a a temperature sensor 45 arranged.

Particularly important is the training of the coil carrier 15 ,

It is an injection molded part, which consists of a corresponding injection-moldable, ceramic material with a high thermal conductivity of at least 15 Wm ^-1 K ^-1 . It has been found that silicon nitride (Si ₃ N ₄ ceramic) is particularly suitable. The special properties of silicon nitride ceramics allow the coils 14 directly on the cylindrical section 16 winding up, without insulating documents are necessary. Because silicon nitride ceramic is an electrical insulator. Insulating documents would be necessary, for example, in a metal coil carrier, since the usual, insulating coatings of coil windings can break and in this case there would be a risk of short circuit.

The high thermal conductivity of the silicon nitride coil carrier 15 ensures optimum transmission through the coils 14 the electromagnet generated heat on the glue.

At the same time, the silicon nitride ceramic is temperature-resistant, so that it also with long operating times of the glue valve 10 no harm.

By the coil carrier 15 injection molding can also be a cost-effective production of the same possible.

The coil carrier 15 is - as already mentioned - in the valve housing chamber 13 of the valve housing 11a arranged. This chamber 13 or this interior is through a lower bottom wall 36a of the valve housing 11a , through lateral walls 36b of the valve housing 11a as well as by a cover wall 36c of the valve housing 11a limited and included. The top wall 36c is while part of a separate cover part 41 of the valve housing 11a ,

Between the walls 36a . 36b . 36c and the coil carrier 15 is a circulating space 37 educated.

As part of the production of the glue valve 10 this freedom becomes 37 according to a further special feature of the invention with a heat-conductive potting compound 39 filled, the heat conductivity value is preferably between 0.5 Wm ^-1 K ^-1 and 2.0 Wm ^-1 K ^-1 .

This potting compound 39 contacts the coils 14 , especially those to the side walls 36b of the valve housing 11a showing page (s). The turns of the coils ( 14 ) are usually arranged so that certain spaces or channels are formed between them. Through these flows the potting compound 39 through to the bobbin 15 ,

As a result, at least a plurality of the coil turns into the potting compound 39 at least partially, preferably completely embedded.

The thermal conductivity of the potting compound 39 ensures optimum temperature distribution along the coils 14 , Possible local heat peaks, especially in the coils 14 or in the coil carrier 15 , are degraded in this way or can not even build up, so over the entire bobbin 15 as even heat transfer as possible within the same (in the interior 18 ) glue takes place.

The potting compound 39 also ensures a permanent connection of the walls 36a -C of the valve body 11a with the coil carrier 15 or the coils arranged thereon 14 ,

As for the production of the glue valve 10 concerns, so form the valve unit 11 and the supply unit 12 separate modules, which are pre-assembled separately and later flanged or fastened together.

In a special way while the valve unit 11 manufactured separately: the coil carrier 15 the valve unit 11 is first - as already described - injection molded from silicon nitride as part of an injection molding process. Later the coils 14 the two electromagnets on the finished bobbin 15 wound. The coil carrier 15 together with coils 14 comes with coil carrier gaskets 40 in the already (at first without cover part 41 ) preassembled housing 11a the valve unit 11 used. Subsequently, the lid part 41 put on (compare three ).

Via a filling channel 42 from the housing chamber 13 up to the outside of one of the side walls 36b is guided, namely up to an opening 43 in the side wall 36b , then become the space already described above 37 as well as the free spaces / channels between the turns of the coil 14 with the potting compound 39 filled.

Following this, the thus pre-assembled and filled unit is placed in a vacuum or space. Under the appropriate vacuum conditions, any air bubbles in the potting compound gas 39 which would lead to a deterioration of the thermal conductivity.

Subsequently, said unit is heated (baked) in a heater such as an oven.

Various other components of the valve unit 11 , in particular the coil carrier 15 together with the coils 14 , the closing organ 19 , the magnet holder 30 , other seals and the nozzle 22 After cooling, the preassembled unit then into the valve housing chamber 13 inserted and mounted.

Finally, the lock nut 38 on the thread approach 35 screwed on, as well as over the thread 46 with the lid part 41 connected.

LIST OF REFERENCE NUMBERS

10

Leinventil

11

valve unit

11a

valve housing

12

supply unit

12a

housing supply

13

Valve housing chamber

14

Do the washing up

15

coil carrier

16

hollow cylindrical section

17

surface

18

inner space

19

closure member

20

shaft

21

Bullet

22

valve opening

23

jet

24

hose connection

25

tube

26

glue channel

27

filter

28

glue channel

29

guide piece

30

magnetic holder

30a

plug

30b

plug

31

line feed

32

control line

33a

plug holder

33b

plug holder

34

power line

35

threaded extension

36a

wall

36b

wall

36c

wall

37

free space

38

locknut

39

potting compound

40

seals

41

cover part

42

filling channel

43

opening

44

Cartridge Heaters

45

temperature sensor

46

thread

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 102010034761 [0002]

Claims (10)

Valve for flowable media, in particular glue valve, with at least one electromagnet, with which a closing element ( 19 ) of the valve ( 10 ) is movable and with the targeted heat to the flowable medium, preferably hot glue, transferable, wherein the at least one electromagnet at least one coil ( 14 ), which on a coil carrier ( 15 ) is arranged, which the closure member ( 19 ) at least partially surrounds, characterized in that the entire coil carrier ( 19 ), but at least the area ( 16 ) of the bobbin carrier ( 15 ), on which immediately windings of the coil ( 14 ), made of an injection-moldable, ceramic material having a high thermal conductivity of at least 15 Wm ^-1 K ^-1 , more preferably of silicon nitride. Valve according to claim 1, characterized in that the ceramic material, preferably the silicon nitride, has a thermal conductivity of at least 25 Wm ^-1 K ^-1 . Valve according to claim 1 or 2, characterized in that the coil carrier ( 15 ) is an injection molded part injection-molded from the ceramic material. Valve according to one or more of the preceding claims, characterized in that the coil carrier ( 15 ) together with the at least one coil ( 14 ) in a particular at least partially hollow cylindrical chamber ( 13 ) within the valve housing ( 11a ), wherein at least one free space area ( 37 ) between at least one wall ( 36a . 36b . 36c ) the chamber ( 13 ) and the at least one coil ( 14 ) and / or the coil carrier ( 15 ) with a thermally conductive potting compound ( 39 ), preferably a potting compound ( 39 ) whose thermal conductivity value lies between 0.5 Wm ^-1 K ^-1 and 2.0 Wm ^-1 K ^-1 . Valve according to claim 4, characterized in that the chamber wall ( 36a . 36b . 36c ) forms a Gehäuseaußenwandung. Valve according to claim 4 or 5, characterized in that the valve has a filling channel ( 42 ) received from the chamber ( 13 ) to the outside of a housing wall ( 36b ) of the valve ( 10 ) is guided, and over the chamber from the outside with the potting compound ( 39 ) is fillable. Valve according to one or more of the preceding claims, characterized in that the potting compound ( 39 ) the coil carrier ( 13 ), the at least one coil ( 14 ) and the at least one chamber wall ( 36a . 36b . 36c ) inseparably connects with each other. Valve according to one or more of the preceding claims, characterized in that the valve ( 10 ) has two detachably interconnected modules, namely a valve unit ( 11 ), in which the closure member ( 19 ), which has at least one coil ( 14 ) and the coil carrier ( 15 ), and a supply unit ( 12 ), in which a connection ( 24 ) for a supply line ( 25 ) is arranged for the flowable medium, in particular a hose, and a supply for power and / or control lines. Valve according to claim 8, characterized in that the valve unit ( 11 ) a plug part ( 30b ), from the power and / or control lines ( 34 ) to at least one electrical component of the valve unit ( 11 ), preferably to the at least one coil ( 14 ), wherein the plug part ( 30b ) during assembly of the valve ( 10 ) in a suitable plug part ( 30a ) of the supply unit ( 12 ) is pluggable, from the power and / or control lines ( 32 ) to the feeder ( 31 ) of the supply unit ( 12 ) are guided. Method for producing a valve according to Claim 1, characterized by the following steps a) a coil carrier ( 15 ) is injection-molded from an injection-moldable, ceramic material having a high thermal conductivity of at least 15 Wm ^-1 K ^-1 , b) at least one coil ( 14 ) at least one electromagnet is placed on the injection-molded coil carrier ( 15 ), c) the coil carrier ( 15 ) together with the at least one coil ( 14 ) is placed in a chamber ( 13 ) of the valve housing ( 11a d) via a filling channel ( 42 ) issued by the Chamber ( 13 ) to the outside of a wall ( 36b ) of the valve housing ( 11a ), a free space between at least one of the chamber ( 13 ) limiting chamber wall ( 36a . 36b . 36c ) and the at least one coil ( 14 ) and / or the coil carrier ( 15 ) filled from the outside with a potting compound.

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