EP4063026B1 - Application device - Google Patents

Description

The invention relates to an application device for applying a viscous medium, in particular hot melt adhesive, to a substrate, and comprises a base body and a plurality of application heads, which are arranged next to one another in a row along a transverse axis of the application device and are attached to the base body.

Such an application device is, for example, from DE 10 2013 101 637 A1 known. Application devices of this type are used in particular for an intermittent application of the medium in the form of dots or beads onto the substrate guided past the application device, for example in the form of a web material.

The application device described there has a large number of application heads, each of which includes a housing. The housings each have a nozzle chamber with a feed channel and an outlet nozzle for the viscous medium. Furthermore, a nozzle needle is provided which passes through the nozzle chamber and whose tip rests on a nozzle needle seat of the outlet nozzle in order to close it. By means of an actuating device, the nozzle needle can be displaced axially along an adjustment axis in order to open and close the outlet nozzle. The housing has a cylinder chamber in which a piston is guided in an axially displaceable manner. This piston-cylinder unit is designed as a double-acting pneumatic actuating cylinder and is part of the actuating device for adjusting the nozzle needle. The housing has a rectangular outer profile, transverse to the adjustment axis, so that several application heads can be arranged next to one another in a simple manner, with the application heads being able to rest against one another with side surfaces of the housing.

Two screws are provided to fasten the individual application heads. which are guided in the direction of the transverse axis on both sides of the cylinder chamber through fastening openings in the housing and are screwed into threaded holes in the base body. The screws are supported on a side facing away from the base body with a screw head against the housing in order to brace it against the base body.

The distance between the application nozzles of the individual application heads is determined on the one hand by the width of the piston or the width of the cylinder chamber in the direction of the transverse axis. On the other hand, the distance between the application nozzles is determined by the thickness of the screws or the screw heads for fastening the application heads.

The sizes of the effective piston surfaces of the piston and thus the width of the cylinder chambers are structurally specified to the forces required to close the outlet nozzle by means of the nozzle needle. Particularly when intermittently applying spots of the viscous medium at short intervals, the nozzle needle must be moved quickly, which requires large actuation forces. This requires large piston surfaces, which in the case of circular piston surfaces means that the distances between the application heads and thus the distances between the points that can be applied are relatively large in the direction of the transverse axis. In the DE 10 2013 101 637 A1 It is therefore proposed that the piston surface has a longitudinal extent in the direction of a longitudinal axis which is greater than a width extent in the direction of a transverse axis arranged transversely to the longitudinal axis. However, this requires complex production of the cylinder bores and pistons.

The document US2008110939 discloses an adhesive dispensing device comprising a dispensing module, a liquid delivery component, and a fastening system. The fastening system includes a stationary component and a fastener pivotally connected to the stationary component. The fastener is configured to apply a clamping force to the delivery module to connect the delivery module to the fluid delivery component.

The document EP 0 908 240 A2 discloses a device for dispensing an adhesive. A dispenser module is attached to a service block with mounting screws.

The object of the present invention is to provide an application device in which the distance between adjacent outlet nozzles of application heads can be reduced in a simple manner.

The object is achieved by an application device for applying a viscous medium, in particular hot melt adhesive, to a substrate, which comprises a base body and a plurality of application heads, which are arranged next to one another in a row along a transverse axis of the application device and are attached to the base body. The application heads each have at least one recess which, together with a recess in an adjacent application head, forms a fastening opening. Furthermore, there is a bolt in each of the fastening openings, which is fastened to the base body and is supported on a side of the application heads facing away from the base body against both application heads forming the respective fastening opening.

Due to this arrangement, not two fasteners, but only one fastener are required on the mutually facing sides of two adjacent application heads. This allows the width of the application heads to be reduced in the direction of the transverse axis compared to the known application heads from the prior art. In this way, the distance between applications of the viscous medium on the substrate can ultimately be reduced.

At least one of the bolts can be designed as a screw which is screwed into a threaded hole in the base body and has a screw head with which the screw is supported against the application heads on a side facing away from the base body. Each screw is thus axially supported with the screw head against the two application heads, which together form the fastening opening in which the screw sits.

Alternatively, it is also conceivable that the bolt is a threaded bolt that is screwed into a threaded hole in the base body and carries a nut on the side facing away from the base body, which is axially supported against the application heads. This means that there is no screw head provided, but rather a screw nut that is screwed onto the threaded bolt. The threaded bolt can also be firmly connected to the base body, for example by means of welding, soldering, gluing or similar.

The recesses can each be formed in a side surface of the housing of the application heads.

Two application heads arranged next to each other can have side walls facing one another, which can also be in contact with one another, whereby the Recesses are arranged in the mutually facing side walls.

The recesses can each be designed as a groove in one of the side surfaces of one of the application heads, the groove being open towards an adjacent application head. The mutually facing grooves of adjacent application heads thus together form a continuous channel-like opening. The individual grooves can have any cross-sectional design, for example in the shape of a segment of a circle, a semicircle or in the form of a polygon, such as triangular or rectangular.

The application heads can each have two recesses facing away from one another, so that they each form a fastening opening with a recess in an adjacent application head. This means that the application heads can be made narrower on two sides.

The fastening openings can be cylindrical. In one embodiment, the recesses can each be designed in a semi-cylindrical shape. It is also conceivable that the recesses have the shape of a circular segment in cross section, different from a semicircle, with those recesses that together form a fastening opening are each designed in cross section such that the circular segment-shaped cross sections together form a circular cross section.

The application heads can each have a fastening surface with which the application heads are held in contact with the base body. The base body can be heated so that heat transfer from the base body to the application head is ensured through the contact between the fastening surface and the base body.

The application device can further comprise end modules which are attached to the base body at the ends of the row of application heads.

The end modules can each have a recess which forms a fastening opening with one of the recesses of the adjacent application head.

The end modules can each be additionally attached to the base body. For example, they can have a fastening hole in which a fastening screw sits, which is screwed into a threaded hole on the base body.

Alternatively, it is also conceivable that instead of the fastening screw, a fastening bolt is provided in the form of a threaded bolt, which is screwed into a threaded hole in the base body and carries a nut on the side facing away from the base body, which is axially supported against the end module. This means that there is no screw head provided, but rather a screw nut that is screwed onto the threaded bolt. The threaded bolt can also be firmly connected to the base body, for example in a materially bonded manner.

In principle, the bolt, regardless of its design, can penetrate the fastening openings in a direction transverse to the transverse axis.

Figur 1

eine perspektivische Darstellung einer Auftragsvorrichtung mit einem Substrat in Form einer Trägerbahn, auf die viskoses Medium, z. B. Heißschmelzkleber aufgetragen wird,

Figur 2

eine Frontansicht zweier benachbarter Auftragsköpfe gemäß Figur 1,

Figur 3

eine Seitenansicht eines der Auftragsköpfe gemäß Figur 2 und

Figur 4

einen Längsschnitt des Auftragskopfs gemäß Figur 3.

An embodiment of an application device is explained in more detail below with reference to the drawings. This shows:

Figure 1

a perspective view of an application device with a substrate in the form of a carrier web onto which viscous medium, e.g. B. hot melt adhesive is applied,

Figure 2

a front view of two adjacent application heads Figure 1 ,

Figure 3

a side view of one of the application heads according to Figure 2 and

Figure 4

a longitudinal section of the application head Figure 3 .

Figure 1 shows a perspective view of an application device with a base body 1, which extends in the direction of a transverse axis Q. On the base body 1, a plurality of application heads 2 are arranged in a row next to one another along the transverse axis Q and attached to the base body 1. The individual application heads 2 are coated with viscous medium, in particular hot melt adhesive, via the base body 1. provided. For this purpose, supply channels (not shown) are arranged in the base body 1. In addition, the application heads 2 are supplied with compressed air via the base body 1 in order to operate them. For this purpose, a compressed air supply 3 is connected to the base body 1, with compressed air channels (not shown) in the base body 1 connecting the compressed air supply 3 to the application heads 2.

At the ends of the row of application heads 2, an end module 4, 5 is attached to the base body 1. The end modules 4, 5 are “blind modules” that are not used to apply viscous medium. They serve exclusively to attach the application heads to the ends of the row of application heads 2, as will be explained in more detail below.

The application device is arranged in such a way that, based on a vertical axis H, which runs perpendicular to the transverse axis Q, a carrier web 6 is moved under the application device in the direction of a transport direction T, with adhesive dots 7 and/or adhesive strips 8 passing through the carrier web 6 during the movement Application heads 2 are applied to the carrier web 6. The transport direction T runs parallel to a longitudinal axis L, which is arranged perpendicular to the transverse axis Q and the vertical axis H.

The Figure 2 shows a front view of two application heads 2, 2 ', which are arranged directly next to each other. The Figure 3 shows one of the two in Figure 2 shown application heads 2 in a side view. The two Figures 2 and 3 are described together below. The in Figure 2 Application head 2 shown on the left is described in more detail. Features of the in Figure 2 The application head 2 'shown on the right, which correspond to features of the left application head 2, is provided with the same reference numbers supplemented by an apostrophe.

The application head 2 has an in Figure 2 first side surface arranged on the left and an in Figure 2 second side surface 10 arranged on the right, both of which are arranged perpendicular to the transverse axis Q. The in Figure 2 The application head 2 shown on the left has its second side surface 10 in contact with the first side surface 9 'of the one shown on the right Application head 2'. In the row of application heads 2, 2 'according to Figure 1 are each a first side surface of an application head in contact with a second side surface of a further adjacent application head.

The application head 2 has a groove-shaped first recess 11 in the first side surface 9. A groove-shaped second recess 12 is arranged in the second side surface 10. In the exemplary embodiment shown, the recesses 11, 12 are semi-cylindrical in shape and extend parallel to the longitudinal axis L of the application device, i.e. transversely to the transverse axis Q. Alternatively, the recess 11, 12 can also have a different cross-sectional shape, such as in the shape of a segment of a circle or rectangular, as long as they are open to the immediately adjacent application head 2, 2 '. Thus form, as in Figure 2 shown, the second recess 12 of the application head 2 shown on the left together with the first recess 11 'of the application head 2' shown on the right together form a channel-like fastening opening 13 parallel to the longitudinal axis L, the fastening opening 13 being cylindrical.

As in Figure 3 As can be seen, a bolt in the form of a screw 14 sits in the fastening opening 13. The screw 14 has a threaded shaft 15 which is guided through the fastening opening 13 and is screwed into a threaded hole 17 in the base body 1. On a side facing away from the base body 1, the screw 14 has a screw head 16, which is axially clamped against clamping surfaces 18 of the two application heads 2 that form the fastening opening 13 and which point away from the base body 1. As a result of this tension, a fastening surface 19 of the two application heads 2 forming the fastening opening 13 is clamped against the base body 1 in contact. This serves in particular for the temperature transition between the heated base body 1 and a housing of the application head 2. As in Figure 1 As can be seen, 2 end modules 4, 5 are arranged at the ends of the row of application heads, which have a recess pointing towards the respective adjacent application head in order to form a fastening opening together with the recess of the application head. The end modules 4, 5 are additionally firmly connected to the base body 1 by fastening means not shown here.

Figure 4 shows a longitudinal section of the application head according to Figure 3 . The application head comprises a housing 20 in which a piston-cylinder unit is arranged. The piston-cylinder unit has a cylinder which is represented by a cylinder bore 21 within the housing 20. The term "cylinder bore" does not mean that it has to be a bore in the form of a circular cylinder with a circular cross section. The cylinder bore 21 can also have a cross section that is elongated, with the cylinder bore 21 having a greater extent, for example, in the direction of a longitudinal axis L than in the direction of a transverse axis Q, with the longitudinal axis L and the transverse axis Q perpendicular in the exemplary embodiment shown are arranged to each other and perpendicular to the vertical axis H. The cylinder bore 21 starts from a top side of the housing 20 and extends into the depth of the housing 20 in the direction of a vertical axis H.

The piston-cylinder unit is used to actuate a nozzle needle 22, which is axially adjustable within the housing 20 along the vertical axis H. An outlet nozzle 23 for the viscous medium, here for a hot melt adhesive, is also provided on the housing 20. The nozzle needle 22 serves to open and close the outlet nozzle 23.

The piston-cylinder unit represents an actuating device for the nozzle needle 22. The piston-cylinder unit further comprises a piston 24, which is adapted to the inner contour of the cylinder bore 21 and is guided in the cylinder bore 21 in an axially adjustable manner along the vertical axis H. Two sealing rings 25, 26 serve between the piston 24 and the inner surface of the cylinder bore 21 to seal the piston 24 from the cylinder bore 21. The piston 24 has an upper piston surface 27 and a lower piston surface 28, each of which can be acted upon by compressed air force. The piston-cylinder unit is therefore designed as a pneumatic actuating cylinder. In principle, however, it is also conceivable that it is a hydraulic actuating cylinder. To pressurize the piston surfaces 27, 28, an air inlet 29 is used to open the outlet nozzle 23 and an air inlet 30 is used to close the outlet nozzle 23, the air inlet 29 for opening being connected to a first cylinder space 31 for pressurizing the lower piston surface 27. The air inlet 30 for closing is connected to a second cylinder space 32, which serves to pressurize the upper piston surface 27.

The cylinder bore 21 is in the in Figure 4 illustrated orientation of the housing 20 is closed upwards by a cover 33, which is sealed in the cylinder bore 21 by means of sealing rings 34 and is fixed to the housing 20 by fastening screws (not shown). A spring element 35 is arranged in the cover 33, which is supported on the one hand against the cover 33 and on the other hand against the piston 24 and acts on the piston 24 in the direction of a closed position for closing the outlet nozzle 23. This ensures that the outlet nozzle 23 is closed even in the event of a pressure loss in the cylinder spaces 31, 32.

The nozzle needle 22 is firmly connected to the piston 24 and is axially displaced by it. Here, the nozzle needle 22 is guided through a needle channel 36 within the housing 20 and extends to the outlet nozzle 23, which is located on the side of the housing 20 facing away from the cover 33. The needle channel 36 is adjoined by a nozzle chamber 37, through which the nozzle needle 22 is also guided. The nozzle chamber 37 is connected via a feed channel 38 to an inlet 39 for viscous medium, here hot-melt adhesive, and is supplied with hot-melt adhesive via this. In a closed position of the piston 24 there is a tip 40 of the nozzle needle 22, as in Figure 4 shown, in contact with a nozzle needle seat 41 of the outlet nozzle 23, so that an outlet channel 42 of the outlet nozzle 23 is closed. In an open position of the piston 24, the nozzle needle 22 is opposite that in Figure 4 shown position axially shifted upwards, the tip 40 being lifted from the nozzle needle seat 41, so that the outlet channel 42 is connected to the nozzle chamber 37 and hot melt adhesive can be conveyed from the outlet channel 42.

Reference symbol list

1

Basic body

2, 2`

Order header

3

Compressed air supply

4

End module

5

End module

6

Carrier track

7

Glue dot

8th

Adhesive strips

9, 9`

first side surface

10, 10'

second side surface

11, 11'

first recess

12, 12'

second recess

13

Fastening breakthrough

14

screw

15

Threaded shaft

16

screw head

17

Threaded hole

18

clamping surface

19

mounting surface

20

Housing

21

Cylinder bore

22

nozzle needle

23

Exit nozzle

24

Pistons

25

sealing ring

26

sealing ring

27

upper piston surface

28

lower piston surface

29

Opening air inlet

30

Air inlet to close

31

first cylinder chamber

32

second cylinder chamber

33

Lid

34

sealing ring

35

Spring element

36

Needle channel

37

nozzle chamber

38

feed channel

39

inlet

40

Great

41

Nozzle needle seat

42

Exit channel

L

Longitudinal axis

H

vertical axis

Q

Transverse axis

T

Transport direction

Claims (13)

1. A dispenser for applying a viscous material, in particular hot melt adhesive, to a substrate, comprising:

   a base body (1), and

   a plurality of dispensing modules (2, 2') arranged side by side in series along a lateral axis (Q) of the dispenser and attached to the base body (1),

   characterized in

   that the dispensing modules (2, 2') each have at least one recess (11, 11', 12, 12') which, together with a recess (11, 11', 12, 12') of an adjacent dispensing module (2, 2'), forms a fastening aperture (13), and

   that in each of the fastening apertures (13) a bolt (14) is seated, the bolt is fastened to the base body (1) and is supported on a side of the dispensing modules (2, 2') facing away from the base body (1) against both dispensing modules (2, 2') forming the respective fastening aperture (13).
2. The dispenser according to claim 1,
   characterized in
   that each of the bolts is designed as a screw (14) which is screwed into a threaded bore (17) of the base body (1) and has a screw head (16) with which the screw (14) is supported against the dispensing modules (2, 2') on a side of the dispensing modules facing away from the base body (1).
3. The dispenser according to claim 1 or 2,
   characterized in
   that the recesses (11, 11', 12, 12') are each formed in a side surface (9, 9', 10, 10') of one of the dispensing modules (2, 2').
4. The dispenser according to one of claims 1 to 3,
   characterized in
   that two dispensing modules (2, 2') arranged next to one another have mutually facing side surfaces (9, 9', 10, 10'), the recesses (11, 11', 12, 12') being arranged in the mutually facing side surfaces (9, 9', 10, 10').
5. The dispenser according to claim 3 or 4,
   characterized in
   that the recesses (11, 11', 12, 12') are each formed as a groove in one of the side faces (9, 9', 10, 10') of one of the dispensing modules (2, 2'), the groove being open towards an adjacent dispensing module (2, 2').
6. The dispenser according to one of claims 1 to 5,
   characterized in
   that the dispensing modules (2, 2') each have two recesses (11, 11', 12, 12') which face away from one another.
7. The dispenser according to one of claims 1 to 6,
   characterized in
   that the fastening apertures (13) are cylindrical in shape.
8. The dispenser according to one of claims 1 to 7,
   characterized in
   that the recesses (11, 11', 12, 12') are semi-cylindrical in shape.
9. The dispenser according to one of claims 1 to 8,
   characterized in
   that the dispensing modules (2, 2') each have a fastening surface (19) with which the dispensing modules (2, 2') are held in contact with the base body (1).
10. The dispenser according to one of claims 1 to 9,
    characterized in
    that an end module (4, 5) is fastened to the base body (1) at each end of the row of dispensing modules (2, 2').
11. The dispenser according to one of claims 1 to 10,
    characterized in
    that the end modules (4, 5) each have a recess which forms a fastening aperture (13) with one of the recesses (11, 11', 12, 12') of the respective adjacent dispensing modules (2, 2').
12. The dispenser according to one of claims 1 to 11,
    characterized in
    that the end modules (4, 5) each have a fastening hole in which a fastening screw is seated, which is screwed into a threaded bore on the base body (1).
13. The dispenser according to one of claims 1 to 12,
    characterized in
    that the bolts (14) pass through the fastening apertures (13) in a direction transverse to the lateral axis (Q).

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