EP2301678A1 - Device with bar-form nozzle assembly and method for dispensing an adhesive material - Google Patents

Abstract

The device has a bar-shaped nozzle arrangement with a nozzle body (30) supported with respect to another nozzle body (21). One of the nozzle bodies (30) is provided in upper and lower positions in two conditions. Each hollow needle (24) fits in a corresponding valve seat (31) of the former body such that nozzle openings (32) lying below the seat are closed. Each needle releases the seat such that an adhesive discharges from an adhesive supply towards an operating zone by an adhesive longitudinal channel, outlet holes (23), passage channels (25) of the needles through the seat and the openings.

Description

The invention relates to devices with bar-shaped nozzle arrangement and corresponding method for dispensing an adhesive.

In particular, the present invention relates to an apparatus for applying a flowable moisture-curing medium (e.g., adhesive or sealant) to a workpiece. In particular, it is about the use of 1-component PUR (polyurethane) adhesive.

In numerous industrial machining processes adhesives, sealants and similar flowable media are used, which are applied or sprayed onto a workpiece in liquid form.

For economic reasons, the devices for this must be suitable for different applications or workpieces of different sizes to be bonded or sealed.

In part, there are devices having a series of nozzles, for example, in a common comb-like arrangement. Some of these nozzles can be closed with a slider or piston to adjust the application width. This type of device has the advantage that only those nozzles are actuated, which are actually required due to the dimensions of the workpiece. The other nozzles remain closed.

There are also approaches with a series of nozzles, all of which can be operated individually.

For a number of industrial applications but the cost of such devices is too large. This is especially the case when it comes to order widths of more than 1 meter to allow. The costs of prior art devices go up significantly with the order width. If one assumes a nozzle spacing of e.g. 10mm out, then with a job width of 1 meter approximately 100 nozzles in a row next to each other must be arranged. It is obvious that the juxtaposition of 100 individually controllable nozzles is complicated and expensive.

Another aspect is the robustness of such a device. When it comes to the gluing of large elements, e.g. Wood composite elements is, then the device must be designed to be robust.

Often, for the gluing of large elements, e.g. Wood composite elements, moisture-curing adhesive, e.g. PUR 1-component adhesive used. In order to prevent the moisture-curing adhesive from hardening in the nozzles, special measures must be taken.

The corresponding adhesives cure as soon as they come into contact with moisture. These adhesives are sometimes referred to as moisture-curing cold glue or moisture-curing adhesive. Once these adhesives come in contact with moisture, begins to use the crosslinking process, which ultimately leads to the curing of the adhesive. Once the adhesive has cured, it can no longer be converted into the liquid form, as is the case with hot glue, for example.

Unfortunately, however, such moisture-curing adhesives are difficult to handle. Particularly critical is the cleaning of valves, nozzles and tools as the adhesive begins to harden after it has absorbed moisture.

Known devices have some drawbacks that occur especially when processing media that are moisture-curing. In addition to the high design overhead, leaks, dehydration and inaccurate or inefficient application of the flowable medium must be cited.

There are devices that are equipped with several nozzles in one housing. By a common slide or piston, a part of the nozzles can be separated from the supply of the medium. But even here the design effort is relatively large.

Often, membrane-based application systems are used to deliver or apply such moisture-curing adhesives, as the diaphragm valves provide good sealing between the adhesive and the air. However, the membrane-based application systems have a number of disadvantages. Among other things, the diaphragm valves tolerate no pressures that are above 20 bar. In addition, the life (calculated in number of valve strokes) is relatively low and the diaphragm valves are expensive. Such solutions are therefore not suitable for large job widths and for devices that need to be very robust.

Especially when processing moisture-curing media has been shown that it comes with an individual or group-wise shutdown of individual nozzles for premature curing of the medium. Thereby supply lines, the nozzle mechanism or the nozzle openings are dirty or even completely blocked. Depending on the medium that was used, the cleaning effort can be enormous. During such cleaning, the device is necessarily out of service, which has an impact on the economy. In the mentioned membrane-based application systems, the frequent change of diaphragm valves is added.

However, there has been a long-felt need to provide application systems for moisture-curing media that provide a 1-meter or more application width. In addition, such an order system should be robust, easy to maintain, clean and inexpensive to purchase.

Against this background, the object was to provide a device for applying a flowable, moisture-curing medium having an application width of 1 meter and more and which is preferably adaptable adaptable to different large workpieces or application conditions and the mentioned disadvantages of premature curing or avoiding soiling as much as possible.

In addition, the task is to create a corresponding method.

The object is achieved by a device according to claim 1.

A first device according to the invention is characterized in that it comprises a bar-shaped nozzle arrangement, which is arranged horizontally above a working zone. The nozzle assembly includes a first nozzle body having an adhesive longitudinal channel which extends over a total length parallel to a longitudinal axis which corresponds approximately to an application width of the device. In the lower part of the nozzle body m output holes are provided, which penetrate into the adhesive longitudinal passage and which are arranged in a row parallel to the longitudinal axis. The number m is an integer> 10. Preferably, this number is> 50. An adhesive feed is provided which is fluidically connected to the adhesive longitudinal channel. A second Nozzle body is supported relative to the first nozzle body so as to be able to move up and down with respect to the first nozzle body. On the second nozzle body are provided m valve seats and m below the valve seats located nozzle openings, which are arranged in a row parallel to the longitudinal axis. Furthermore, m hollow needles are provided. Each hollow needle has a through-channel and a needle tip, and one hollow needle each is fluidically connected to one of the m output holes so that adhesive can penetrate from the adhesive longitudinal channel into the through-channels. In a first state, the second nozzle body is in an upper position and each of the hollow needles sits with its respective needle tip in a corresponding valve seat of the second nozzle body. Thus, the nozzle openings located below the valve seats are closed. In a second state, the second nozzle body is in a down position and each of the hollow needles releases the corresponding valve seat with its respective needle tip to allow adhesive from the adhesive feed through the glue longitudinal channel, through the m exit holes and through channels of the m hollow needles through the valve seats and the m corresponding nozzle openings can escape in the direction of working zone.

In the subclaims further advantageous embodiments of the invention are listed.

pictures

In the following, further details and advantages of the invention will be described in detail by means of embodiments and partly with reference to the drawing. All figures are schematic and not to scale, and corresponding structural elements are given the same reference numerals in the different figures, even if they are designed differently in detail. The same reference numerals in the following mean the same or equivalent components.

Show it:

Fig. 1

a perspective view of a first embodiment of the invention;

Fig. 2

a schematic perspective view of a second embodiment of the invention;

Fig. 3

a section through a nozzle body of another embodiment of the invention;

Fig. 4

a schematic plan view of a part of another embodiment of the invention;

Fig. 5

a section through a nozzle body of another embodiment of the invention.

Detailed description of the embodiments

• sehr gute Adhäsionseigenschaften;
• geringes Einlaufen/Schrumpfen des Klebstoffs;
• Beständig gegen Mineralöle;
• Klebstofffilm mit wesentlich höherer mechanischer Festigkeit als PUR Heissleim;
• Kälte- und wärmebeständiger als PUR Heissleim, sowie ausgezeichnete Flexibilität auch bei niedrigen Temperaturen;
• Besonders gut für Flächenverklebungen und Keilverzinkungen im Holzbau geeignet;
• Minimale Auftragstärken von 0,1 bis 0,2 mm sind möglich. Demzufolge ergibt sich ein geringerer Klebstoffverbrauch als bei Heissleim.

In the present invention, mainly PUR 1-component adhesive is used, since this adhesive offers numerous advantages in comparison, for example, with hot-melt adhesives, as illustrated by way of example below:

• very good adhesion properties;
• low shrinkage / shrinkage of the adhesive;
• Resistant to mineral oils;
• Adhesive film with much higher mechanical strength than PUR hotmelt;
• More resistant to cold and heat than PUR hotmelt, as well as excellent flexibility even at low temperatures;
• Particularly suitable for surface bonding and finger-jointing in timber construction;
• Minimum application thicknesses of 0.1 to 0.2 mm are possible. As a result, there is less adhesive consumption than hot glue.

The invention can also be used for other moisture-curing adhesives.

In the following, the principle of the invention with reference to a first Embodiment described. In Fig. 1 a device 10 is shown with bar-shaped nozzle assembly 20, which is arranged horizontally above a working zone A. The nozzle assembly 20 comprises a first nozzle body 21 with adhesive longitudinal channel 22 which extends over a total length L parallel to a longitudinal axis LA, which corresponds approximately to an application width AB of the device 10, as in Fig. 4 can be seen. In the lower region U of the nozzle body 21 are m output holes 23 which penetrate into the adhesive longitudinal channel 22 and which are arranged in a row parallel to the longitudinal axis LA. Details are the exemplary embodiment of Fig. 3 refer to. m is an integer greater than 10 and preferably greater than 50.

Typically, a device 10 according to the invention comprises between 5 and 10 exit holes 23 per 10 cm length (viewed in the direction of the longitudinal axis LA).

There is an adhesive supply 40 fluidly connected to the adhesive longitudinal channel 22 in order to be able to supply adhesive, for example, from a tank 41. A second nozzle body 30 is supported relative to the first nozzle body 21 so as to be able to perform an up and down movement P with respect to the first nozzle body 21 (see FIG Fig. 3 ).

At the second nozzle body 30 are m valve seats 31 and m below the valve seats 31 located nozzle openings 32 are provided, which are arranged in a row parallel to the longitudinal axis LA. The device comprises m hollow needles 24, each hollow needle 24 having a passageway 25 and a needle tip 26, as in FIG Fig. 3 can be seen. Each of the m output holes 23 has a respective hollow needle 24 fluidically connected so that adhesive can penetrate from the adhesive longitudinal channel 21 into the through channels 25.

In a first state, the second nozzle body 30 is in an upper position and each of the hollow needles 24 is seated with its respective needle tip 26 in a corresponding valve seat 31 of the second Nozzle body 30. Thus, the lying below the valve seats 31 nozzle openings 32 are closed.

In a second state, the second nozzle body 30 is in a lower position and each of the hollow needles 24 releases the corresponding valve seat 31 with its respective needle tip 26, thereby allowing adhesive from the adhesive feed 40 through the adhesive longitudinal channel 21, through the m exit holes 23 and through channels 25 of the m hollow needles 24, can escape through the m valve seats 31 and the m corresponding nozzle openings 32 in the direction of working zone A.

In Fig. 2 is indicated that several adhesive webs KR, beads or threads parallel to each other from the nozzle openings 32 exit. For the sake of clarity, only four adhesive webs KR are shown here. The adhesive webs KR, caterpillars or threads are distributed over a workpiece W (in this case a large format plate) which moves below the bar-shaped nozzle arrangement 20. The direction of movement is in Fig. 2 indicated by the arrow V.

In Fig. 3 an embodiment of the device 10 can be seen, in which the second nozzle body 30 comprises a chamber 33 for receiving a barrier liquid S. The barrier liquid S prevents the curing of the adhesive. This chamber 33 surrounds a region of the first nozzle body 21, in which the hollow needles 24 are arranged on the first nozzle body 21, since leaks and leakage of adhesive can occur here.

In Fig. 5 a further embodiment of the device 10 can be seen, in which the second nozzle body 30 comprises a chamber 33 for receiving a barrier liquid S. The barrier liquid S, which in Figure 5 is shown, prevents the curing of the adhesive. This chamber 33 surrounds a region of the first nozzle body 21, in which the hollow needles 24 are arranged on the first nozzle body 21, since leaks and leakage of adhesive can occur here.

The chambers 33, 34 filled with barrier liquid S are preferably provided where seals or sealing rings 35 or 36 are seated. In the Figures 3 and 5 ensure the seals or sealing rings 35, 36 together with the filled with sealing liquid S chambers 33, 34 for a good seal. It comes here neither to the leakage of adhesive nor to the curing of the adhesive.

Preferably, a liquid is used as the sealing liquid S, which is adapted to the adhesive so that the adhesive does not harden on contact with the barrier liquid S. Preferably, the barrier liquid S comprises a plasticizer.

A further chamber (not shown) may also be arranged in the region of the needle tip 26 in the various embodiments.

In Fig. 3 an embodiment of the device 10 can be seen, in which in an upper region of the first nozzle body 21 at least one movable locking needle 27 is arranged. This locking pin 27 penetrates through an overhead hole 28 in the adhesive longitudinal channel 22 a. By means of a closing movement P1, it can be displaced downwards in order to close the exit hole 23 of the adhesive longitudinal channel 22 from the inside with a lower needle area 29.

Another chamber 34 may be arranged in the various embodiments in the region of the locking needle 27, as in Fig. 3 shown.

In Fig. 3 an embodiment of the device 10 can be seen, in which the movable locking needle 27 is resiliently mounted so that it automatically returns to the execution of the shutter movement P1 in an upper starting position. In the upper starting position, the exit hole 23 is open. For resilient mounting, for example, a spring may be provided on the locking pin 27.

In Fig. 3 For example, an embodiment of the device 10 can be seen, in which an adjusting mechanism 60 is provided to act on one or more movable locking pins 27 to cause the closing movement P1 of one or more movable locking pins 27 by this action. For example, the adjustment mechanism 60 may be made similar to a camshaft of an engine.

A preferred embodiment has a block adjustment mechanism 60 to act on a plurality of juxtaposed movable locking pins 27 together. Through this joint action, a block-by-block closing movement P1 of the plurality of adjacent movable locking needles 27 can be triggered so as to be able to set the effectively effective application width AB of the device 10.

In a preferred embodiment, the apparatus 10 has a gantry structure with a working zone A adapted to move workpieces W to be glued below the nozzle assembly 20. Three portal solutions are in the FIGS. 1, 2 and 3 shown.

In a further preferred embodiment, the device 10 comprises means for predetermining a defined dry air flow in the region of the nozzle openings 32. In Fig. 5 a corresponding embodiment of the device 10 can be seen. In order to be able to specify a defined dry air flow, 30 or baffles 37 are arranged in the lower region of the second nozzle body, the dry air through a dry air chamber 38 pass out next to the nozzle openings 32 or let flow past. The lips or baffles 37 are preferably arranged in the lower region of the second nozzle body 30 such that a small air opening 39 results on the circumference of each nozzle opening 32.

In a further preferred embodiment, the in Fig. 5 is shown, the device 10 has a nozzle body 42 which can be screwed into a nozzle seat with internal thread. The nozzle seat is located in The lower portion of the second nozzle body 30. The nozzle chamber Z is located in the interior of the nozzle body 42. Such a nozzle body 42 can be replaced if necessary.

Corresponding details may be, for example, the European patent application EP 09 159 657.7 entitled "MULTIPLE DRY AIR VALVE DEVICE AND METHOD FOR DISPENSING AN ADHESIVE". The device 10 can also be used with a climate chamber according to the German utility model DE202008015257.7 be equipped. The utility model is entitled: "APPARATUS FOR APPLYING A MOISTURE-DISPOSING ADHESIVE".

These measures prevent the exiting adhesive from curing immediately after emergence. It can also be prevented that over time adhesive deposits form around the nozzle openings 32, which can affect the application pattern or which can lead to contamination of the workpiece W.

In the various embodiments, the apparatus 10 includes a drive unit configured to perform the up and down movement P of the second nozzle body 30 with respect to the first nozzle body 21. Actuators or adjusting elements are preferably used as a drive unit. The actuators may e.g. work hydraulically or pneumatically.

In the various embodiments, the device 10 preferably includes a controller 100 (see FIG Fig. 1 ), which causes an upward movement of the second nozzle body 30 with respect to the first nozzle body 21 to release the m nozzle openings 32 so that adhesive can escape. Instead of a controller 100, the movement can also be carried out manually.

In a particularly preferred embodiment (see Fig. 3 ), the hollow needles 24 are designed so that the passage channel 25 has at least one side outlet A1 in the lower region, so that adhesive from the Through passage 25 can enter into a nozzle chamber Z above the valve seat 31.

In the various embodiments, the device 10 preferably includes a controller 100 (see FIG Fig. 1 ), which causes a downward movement of the second nozzle body 30 with respect to the first nozzle body 21 to close the m nozzle openings 32, so that no adhesive can escape. Instead of a controller 100, the movement can also be carried out manually.

Preferably, a controller 100 is provided which controls all (movement) processes.

The device 10 is preferably designed for dispensing moisture-curing adhesive (preferably 1K-PUR).

Particularly advantageous is an application of the device 10 for gluing large format plates W, as in the FIGS. 1, 2 and 4 indicated.

The technical measures described, the maintenance costs compared to conventional devices is significantly lower. The cost per nozzle opening 32 are significantly lower than in conventional approaches. Nevertheless or because of this, the device 10 operates particularly reliably

Claims (14)

Device (10) with bar-shaped nozzle arrangement (20), which is arranged horizontally above a working zone (A), wherein the nozzle arrangement (20) comprises: - A first nozzle body (21) with adhesive longitudinal channel (22) extending over an overall length (L) parallel to a longitudinal axis (LA), which corresponds approximately to an application width (AB) of the device (10), wherein in the lower region (U) of the nozzle body (21) are m exit holes (23) penetrating into the adhesive longitudinal channel (22) and arranged in a row parallel to the longitudinal axis (LA), where m is an integer> 10, an adhesive feed (40) fluidly connected to the adhesive longitudinal channel (22), a second nozzle body (30) mounted relative to the first nozzle body (21) so as to be able to perform an up and down movement (P) with respect to the first nozzle body (21), 30) are provided with valve seats (31) and m below the valve seats (31) lying nozzle openings (32) which are arranged in a row parallel to the longitudinal axis (LA) - M hollow needles (24), wherein each hollow needle (24) has a passage channel (25) and a needle tip (26) and wherein each of the m output holes (23) each have a hollow needle (24) fluidly connected so that the adhesive the adhesive longitudinal channel (21) can penetrate into the through channels (25), wherein in a first state, the second nozzle body (30) is in an upper position and each of the hollow needles (24) with its respective needle tip (26) seats in a corresponding valve seat (31) of the second nozzle body (30) and thus below In a second state, the second nozzle body (30) is in a lower position and each of the hollow needles (24) releases with its respective needle tip (26) the corresponding valve seat (31) thus adhesive from the adhesive feed (40) through the adhesive longitudinal channel (21), through the m output holes (23) and the Passage channels (25) of the m hollow needles (24) through the m valve seats (31) and the m corresponding nozzle openings (32) in the direction of working zone (A) can escape. Device (10) according to claim 1, characterized in that the second nozzle body (30) comprises a chamber (33) for receiving a barrier liquid, said chamber (33) surrounding a portion of the first nozzle body (21) in which the hollow needles ( 24) are arranged on the first nozzle body (21). Device (10) according to claim 1 or 2, characterized in that in an upper region of the first nozzle body (21) at least one movable locking needle (27) is arranged, which penetrates through an overhead hole (28) in the adhesive longitudinal channel (22) and which can be displaced downwards by a closing movement (P1) in order to close with a lower needle area (29) the starting hole (23) of the adhesive longitudinal channel (22). Apparatus (10) according to claim 3, characterized in that the movable locking needle (27) is resiliently mounted so that it automatically returns to the execution of the shutter movement (P1) in an upper initial position and wherein in the upper initial position, the output hole (23). is open. Device (10) according to claim 3 or 4, characterized in that it comprises an adjusting mechanism (60) for acting on one or more movable locking pins (27) in order to prevent, by this action, the closing movement (P1) of one or more movable locking pins (27). 27). A device (10) according to claim 3 or 4, characterized in that it comprises a block displacement mechanism (60) for acting on a plurality of juxtaposed movable locking pins (27) to effect blockwise locking movement (P1) of said plurality adjacent movable locking pins (27) cause, so as to adjust the effective effective application width (AB) of the device (10) can. Device (10) according to any one of the preceding claims, characterized in that it has a gantry structure with a work zone (A) adapted to move workpieces (W) to be glued below the nozzle assembly (20). Device (10) according to one of the preceding claims, characterized in that it comprises a drive unit which is designed to perform the up and down movement (P) of the second nozzle body (30) with respect to the first nozzle body (21). Apparatus (10) according to claim 8, characterized in that it comprises a controller (100) which triggers an upward movement of the second nozzle body (30) with respect to the first nozzle body (21) to release the m nozzle orifices (32) therewith Glue can escape. Apparatus (10) according to claim 7, characterized in that it comprises a controller (100) which triggers a movement of the second nozzle body (30) with respect to the first nozzle body (21) to close the m nozzle openings (32), so that no adhesive can escape. Device (10) according to any one of the preceding claims, characterized in that it comprises a nozzle body (42) with an internal nozzle chamber (Z) which can be screwed into an opening of the second nozzle body (30). Device (10) according to one of the preceding claims, characterized in that on the second nozzle body (30) lips or baffles (37) are mounted in order to allow dry air to flow out in the region of the nozzle openings (32). Device (10) according to one of the preceding claims, characterized in that it is designed for dispensing moisture-curing adhesive. Device (10) according to one of the preceding claims, characterized in that it is designed for gluing large format plates (W).

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