Application device for a viscous adhesive having a rotatable nozzle

Abstract

An application device for a viscous adhesive comprising a base body having a first inlet for a viscous adhesive; and a nozzle body which is rotatable about an axis with respect to the base body and which surrounds a portion of the base body radially on the outside with respect to the axis, wherein, via the interaction of a first dynamic seal with a separating agent chamber, in which a separating agent is stored, the introduction of humidity into the adhesive before it exits the nozzle opening is effectively prevented.

Claims

1. An application device for a viscous adhesive comprising: a base body having a first inlet for a viscous adhesive; and a nozzle body which is rotatable about an axis with respect to the base body and which surrounds a portion of the base body radially on the outside with respect to the axis; wherein the nozzle body has a nozzle channel which has a nozzle opening at a first end for discharging the adhesive from the application device and an inflow entry at a second end; wherein the nozzle body and the base body are aligned in such a way that adhesive can be conveyed into the inflow entry of the nozzle channel via an orifice of the first inlet; wherein a first dynamic seal covers the base body, which rests with an inner side against an outer wall of the base body and with an outer side against an inner wall of the nozzle body; wherein a separating agent chamber is formed which surrounds the base body in the circumferential direction and which is delimited radially inside by the outer wall of the base body and radially outside by the inner wall of the nozzle body; wherein a second inlet for a separating agent is formed in the base body, which is fluidically connected to the separating agent chamber for feeding the separating agent; wherein the first dynamic seal is formed in the direction of the axis between the separating agent chamber and the inflow entry of the nozzle channel of the nozzle body; and wherein an outlet is formed in the base body and is in fluid communication with the separating agent chamber.

2. An application device in accordance with claim 1 wherein the outlet runs parallel to the axis.

3. An application device in accordance with claim 1 wherein at least one of the first inlet and the second inlet runs parallel to the axis.

4. An application device in accordance with claim 1 wherein a second dynamic seal is formed on one side of the separating agent chamber which is opposite the side of the separating agent chamber facing the first dynamic seal.

5. A method for applying an adhesive to a surface to be bonded comprising the use of an application device in accordance with claim 1.

6. The method for applying an adhesive to a surface to be bonded in accordance to claim 5, wherein the adhesive is a polyurethane-based adhesive.

7. The method for applying an adhesive to a surface to be bonded in accordance to claim 5, wherein the surface comprises a windshield; the adhesive is fed into the nozzle channel via the first inlet and is conveyed out of the nozzle channel through a nozzle opening onto the windshield and a bead of adhesive is produced on the windshield by a movement of the application device relative to the windshield in a direction of movement; and the nozzle body is rotated relative to the base body of the application device in such a way that the nozzle opening is oriented opposite to the direction of movement.

8. The method for applying an adhesive to a surface to be bonded in accordance to claim 7, wherein the adhesive is a polyurethane-based adhesive.

9. The method for applying an adhesive to a surface to be bonded in accordance to claim 7, wherein the adhesive is a thixotropic, water-hardening adhesive.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a first cross section through an embodiment of an application device in accordance with the present invention.

(2) FIG. 2 shows a second cross section through the embodiment of the application device in accordance with the present invention shown in FIG. 1.

(3) FIG. 3 shows a detail of the embodiment of the application device in accordance with the present invention shown in FIG. 1.

(4) FIG. 4 shows the application of an adhesive to a windshield using an embodiment of an application device in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(5) For purposes of clarity and ease of reference, following is a description of various components shown in the drawings and their corresponding reference designations:

(6) 1 Application device

(7) 2 Base body

(8) 3 Axis

(9) 4 Nozzle body

(10) 5 First inlet

(11) 6 Second inlet

(12) 7 Outlet

(13) 8 Nozzle

(14) 9 Gear

(15) 10 Drive

(16) 11 Separating agent chamber

(17) 12 First dynamic seal

(18) 13 Nozzle channel

(19) 14 Nozzle opening

(20) 15 Outer wall

(21) 16 Bearing sleeve

(22) 17 Feed line extension

(23) 18 Orifice

(24) 19 Inflow entry

(25) 20 Inner side

(26) 21 Outer surface

(27) 22 Outer side

(28) 23 Inner wall

(29) 24 Feed line

(30) 25 Valve

(31) 26 Adhesive

(32) 27 Windshield

(33) 28 Direction of movement

(34) 29 Second dynamic seal

(35) 30 Surface

(36) 31 First end

(37) 32 Second end

(38) FIG. 1 is a first cross section through an example of an application device 1 for viscous adhesive. The application device 1 comprises a base body 2 and a nozzle body 4 rotatable about an axis 3 with respect to the base body 2. The base body 2 contains all the feed lines for the media necessary for operating the application device 1. In the present example, a one-component adhesive, in particular a polyurethane-based adhesive, is used, which is fed via a first inlet 5 through the base body 2 to the nozzle body 4. In the case of a two-component adhesive, the base body 2 has two first inlets 5 (not shown in this case), which guide the individual components of the adhesive to the nozzle body 4. In the present example, the first inlet 5 extends in the direction of the axis 3 centrally in the base body 2 and is aligned with the nozzle body 4. The base body 2 also has a second inlet 6, which also extends in the direction of the axis 3 and thus runs parallel to the first inlet 5. A separating agent, in particular a fat, is fed via the second inlet 6. Used separating agent is discharged via an outlet 7. The outlet 7 is aligned parallel to the axis 3.

(39) The nozzle body 4 has an exchangeable nozzle 8 which can be adapted to the application and which is easily exchangeable. The interface between the nozzle 8 and the rest of the nozzle body 4 is statically sealed and designed in such a way that no outside air can enter the nozzle channel 13. The nozzle body 4 has a nozzle channel 13 which also extends into and through the nozzle 8, via which the adhesive is guided to a nozzle opening 14 of the nozzle 8 and is discharged through it. The nozzle body 4 extends in the direction of the axis 3 over a portion of the base body 2 and surrounds this portion coaxially. The nozzle body 4 is connected to a gear wheel 9, which is part of a drive 10, by means of which the nozzle body 4 can be rotated relative to the base body 2 about the axis 3.

(40) The nozzle body 4 has a separating agent chamber 11 which can be rotated with the nozzle body 4. In operation, the separating agent chamber 11 is filled with the separating agent. For this purpose, the second inlet 6 opens into the separating agent chamber 11. Used separating agent can be removed again via the outlet 7, which is also connected to the separating agent chamber 11. In this case, it is possible to fill the separating agent chamber 11 before the start of operation of the application device 1 and to renew the filling of the separating agent chamber 11 discontinuously, in which fresh separating agent is pressed through the second inlet 6 into the separating agent chamber 11 and thus used separating agent is fed out of the separating agent chamber 11 into the outlet 7. Alternatively, during operation of the application device 1, separating agent can be continuously fed via the second inlet 6 into the separating agent chamber 11 and from this into the outlet 7. The outlet 7 is connected to a receptacle (not shown in this case) for used separating agent. Whether a continuous or discontinuous filling process of the separating agent chamber 11 takes place is decided in particular depending on the requirements of the adhesive and the application.

(41) The nozzle body 4 is sealed off from the base body 2 via a first dynamic seal 12. The first dynamic seal 12 is designed in particular as a rotary seal. The first dynamic seal 12 surrounds the base body 2, in this example in the region of a feed line extension 17, which includes a part of the first inlet 5. The nozzle channel 13 has a nozzle opening 14 at a first end 31 for discharging the adhesive from the application device 1 and an inflow entry 19 at a second end 32 which is opposite the first end 31, nozzle body 4 and the base body 2 are aligned in such a way that adhesive can be conveyed into the inflow entry 19 of the nozzle channel 14 via an orifice 18 of the first inlet 5 which is designed in this example in the feed line extension 17. Preferably, and in this example, the orifice 18 of the first inlet 5 and inflow entry 19 of the nozzle channel 13 are at least partially, preferably completely, overlapping in a plane perpendicular to the axis 3. The first dynamic seal 12 rests with an inner side 20 against an outer surface 21 of the base body 2 in the region of the feed line extension 17 and with an outer side 22 against an inner wall 23 of the nozzle body 4 (see FIG. 3 in detail). During operation, adhesive is conveyed through the first inlet 5 in the feed line extension 17 through the orifice 18 into the inflow entry 19 and thus into the nozzle channel 13.

(42) The first dynamic seal 12 is not completely tight due to the system design and would allow air with the corresponding humidity to penetrate through the first dynamic seal 12 into the nozzle channel 13 of the nozzle body 4, so that there could be an undesirable reaction with the adhesive. PU-based adhesives in particular are hygroscopic and harden in reaction with water.

(43) In order to restrict hardening to the adhesive discharged through the nozzle opening 14 and to prevent undesired hardening, the second inlet 6 opens into a separating agent chamber 11, so that separating agent can be fed into the separating agent chamber 11 via the second inlet 6. The first dynamic seal 12 is formed in the direction of the axis 3 between the separating agent chamber 11 and the nozzle channel 14 of the nozzle body 4. The separating agent chamber 11 is thus in the only region via which air can reach the transition from the first inlet 5 to the nozzle channel 13.

(44) The separating agent chamber 11 completely surrounds the base body 2 in the circumferential direction in relation to the axis 3 and is delimited radially on the inside by an outer wall 15 of the base body 2 and radially on the outside by an inner wall 23 of the nozzle body 4, so that the separating agent rests against the outer wall 15 of the base body 2. This prevents air from penetrating towards the first dynamic seal 12 and thus prevents air from penetrating into the nozzle channel 13. In this way, undesired hardening in the nozzle channel 13 can be prevented. In this case, the first dynamic seal 12 is the only seal that prevents air from penetrating into the nozzle channel 13. The separating agent chamber 11 rotates with the nozzle body 4 around the base body 2.

(45) The only interface is located between an orifice 18 of the first inlet 5 in the feed line extension 17 and a rotatable inflow entry 19 of the nozzle channel 13 (see also the detail drawing in FIG. 3), through which interface air can reach the adhesive before it exits the nozzle opening 14. The first dynamic seal 12 is formed in the direction of the axis 3 between the separating agent chamber 11 and the inflow entry 19 into the nozzle channel 13. Therefore, the dynamic seal 12, in cooperation with the separating agent chamber 11, ensures that no air comes into contact with the adhesive in the interior of the nozzle body 4.

(46) The nozzle body 4 is attached in a rotationally fixed manner to a bearing sleeve 16 which coaxially surrounds a portion of the base body 2 and which is mounted on the base body 2 via ball bearings 17. The gear 9 is non-rotatably fixed on the bearing sleeve 16. By actuating the gear 9, for example by means of a further gear meshing with it or also by means of a toothed rack as part of the drive 10, the bearing sleeve 16 and thereby the nozzle body 4 and thus the nozzle opening 14 are rotated relative to the base body 2. This makes it possible, for example when applying adhesive to a windshield, to rotate the nozzle body 4 in each case so that the nozzle opening 14 is optimally aligned with the application direction of the adhesive on the windshield.

(47) The application device 1 can be connected to a manipulator or robot arm as well as to a tripod.

(48) Furthermore, a second dynamic seal 29 is formed on one side of the separating agent chamber 11 which is opposite the side of the separating agent chamber 11 facing the first dynamic seal 12. The second dynamic seal 29 prevents the separating agent from escaping from the separating agent chamber 11 and at least slows down the contamination of the separating agent in the separating agent chamber 11. This makes it possible to use the separating agent in the separating agent chamber 11 for a longer period of time. Furthermore, by preventing air from entering the separating agent in the separating agent chamber 11, the accumulation of moisture in the separating agent is slowed down or reduced.

(49) FIG. 2 is a second cross section of the example of the application device 1. To avoid repetition, reference is made here to the description of the first cross section of FIG. 1 and only the further details are explained. FIG. 2 shows the feed line 24 for adhesive, via which the adhesive can be supplied to the first feed line 5 via a valve 25. The nozzle opening 14 has a triangular cross section, so that a bead of adhesive with a triangular cross section can be applied by the application device 1.

(50) FIG. 3 is an enlarged detail of the application device 1 with the first dynamic seal 12 surrounding the feed line extension 17. The first dynamic seal 12 rests with an inner side 20 against an outer surface 21 of the feed line extension 17 and with an outer side 22 against the inner wall 23 of the nozzle body 4.

(51) FIG. 4 shows, very schematically, an example of the application of adhesive 26 to a surface 30 of a windshield 27 by means of an application device 1. In this case, the application device 1 is moved in a direction of movement 28 relative to the windshield 27. The nozzle body 4 is rotated relative to the base body 2 in such a way that the nozzle opening 14 (not shown in this case) is oriented opposite to the direction of movement 28. In addition, the rotatability of the nozzle body 4 relative to the base body 2 allows for a seam closure to be achieved in which the end of the bead of adhesive 26 is connected to the beginning of the corresponding bead, for example if the windshield 27 is provided with adhesive 26 over the entire outer edge.

(52) The application device 1 allows the application of polyurethane-based adhesive to a surface, wherein, via the interaction of a first dynamic seal 12 with a separating agent chamber 11, in which a separating agent is stored, the introduction of humidity into the adhesive before it exits the nozzle opening 14 is effectively prevented. The outlay on equipment required for this purpose is low when using the formation of a first dynamic seal 12 and a separating chamber 11.