Device for applying a viscous material

Abstract

A device for applying a viscous material has: an application tube, which delimits an application duct running in a longitudinal direction from a material inlet opening to a material outlet opening; and a housing, which accommodates at least part of the application tube and has a material supply connection for the viscous material. The application tube has a first tube section, which is fixed on the housing and has the material inlet opening, and a second tube section, which adjoins the first tube section and has the material outlet opening at a free end. A joint connects the first tube section and the second tube section, and a drive device deflects the free end of the second tube section in a transverse direction running transversely to the longitudinal direction.

Claims

1. An apparatus for application of a viscous material, the apparatus comprising: an application tube bounding an application duct running in a longitudinal direction from a material inlet opening to a material outlet opening; a housing that receives the application tube at least partly and that has a material feed port for the viscous material, wherein the application tube has a first tube portion disposed fixed to the housing and provided with the material inlet opening and a second tube portion adjoining the first tube portion and provided at a free end with the material outlet opening; a joint connecting the first tube portion and the second tube portion; and a drive device for deflection of the free end of the second tube portion in a transverse direction oriented transversely relative to the longitudinal direction; wherein the drive device is provided with at least one boom that is joined to the second tube portion and that juts out radially as well as with at least two actuating elements comprising tappets that can be moved by means of respectively one positioning element for urging the at least one boom at various urging points; and wherein the positioning element comprises a pneumatic cylinder, a piezo element, or a moving coil.

2. The apparatus according to claim 1, wherein the joint is a ball joint, a cardan joint or a joint with an elastic connector joining the first tube portion with the second tube portion.

3. The apparatus according to claim 1, wherein the drive device is provided with at least three actuating elements.

4. The apparatus according to claim 1, wherein the actuating elements and the urging points are respectively disposed at constant angular spacings relative to one another and to a longitudinal central axis of the application tube.

5. The apparatus according to claim 1, wherein the tappets are capable of moving forward and back and resting on the at least one boom at the urging points.

6. The apparatus according to claim 5, wherein a restoring spring is associated with each tappet for urging of the at least one boom with a restoring force, which is directed toward the tappet.

7. The apparatus according to claim 1, wherein the positioning elements are moving coils.

8. The apparatus according to claim 1, wherein the drive device has a number of booms, corresponding to a number of actuating elements, in the form of boom arms, that jut out radially at an angular spacing relative to one another.

9. The apparatus according to claim 1, further comprising a needle valve for closing of the application tube, wherein the needle valve has a valve seat disposed in the first tube portion.

10. The apparatus according to claim 9, wherein the needle valve has a needle comprising a prolongation that extends into the second tube portion.

Description

(1) The invention will be explained in more detail hereinafter on the basis of an exemplary embodiment illustrated schematically in the drawing, wherein

(2) FIGS. 1 to 3 show an apparatus for application of a viscous material in three different sectional diagrams, wherein the section planes of FIG. 2 and FIG. 3 are perpendicular to one another and include an angle of 45 with the section plane of FIG. 1.

(3) The material application apparatus 10 illustrated in the drawing is used for the application of viscous material such as adhesive or sealing compound onto a workpiece, such as a body part of a motor vehicle, for example. It has a housing 12, in which an application tube 14 is received, which extends in a longitudinal direction 16. The application tube 14 has, disposed fixed to the housing, a first tube portion 18, which has a material inlet opening 20, as well as, joined flexibly to the first tube portion 18 by means of a ball joint 22, a second tube portion 24, which, at its free end 26 turned away from the first tube portion 18, has a material outlet opening 28. Between the material inlet opening 20 and the material outlet opening 28, an application duct 30 for the viscous material extends, which is bounded by an application tube 14 and into which this material is introduced via a material feed port 32 in the housing 12 through the material inlet opening 20.

(4) In order to be able to swivel the second tube portion 24 relative to the first tube portion 18 on the ball joint 22 with deflection of the free end 26 relative to the longitudinal central axis of the application tube 14 in a transverse direction 34 oriented transversely relative to the longitudinal direction 16, a drive device 36 is provided, which has four booms in the form of boom arms 38, which are disposed in cruciform manner at equal angular spacings relative to one another, which are joined to the second tube portion 24 and which jut out radially. Each of the boom arms 38 is urged on its surface, by a tappet 42 resting loosely thereon, at an urging point 40 disposed at a spacing from the second tube portion 24. All urging points 40 are disposed at the same spacing from the second tube portion 24. For movement of the tappets 42, the drive device 36 has, merely indicated in the drawing, four moving coils (voice coils) 44, which are disposed in the housing 12 and each of which is intended to urge one of the tappets 42 for accomplishment of a forward and back motion. Upon an appropriate activation of the moving coils 44, in which the tappets 42 are moved successively in turn downward for urging of the boom arms 38 onto the urging points 40, an approximately circular movement of the free end 26 and thus of the material outlet opening 28 can be achieved. Restoring springs, which act from underneath against the boom arms 38, may be disposed in the housing 12, opposite the tappets 42.

(5) For closing of the application duct 30, a needle valve 46 is provided, the needle 48 of which is seated in a closed position on a valve seat 50 in the first tube portion 18. This valve seat 50 is disposed just above the ball joint 22. A typical value for the spacing of the valve seat 50 from the ball joint 22 is then one to two cm, whereas a typical value for the length of the second tube portion 24 is three to five cm. In addition, the needle 48 has a prolongation 52 of smaller diameter that extends through the ball joint into the second tube portion 24 and that is disposed at sufficient spacing from the second tube portion 24 even during a deflection of the second tube portion 24 by means of swiveling around the ball joint 22 relative to the first tube portion 18. The prolongation 52 acts as a displacement member, in order to minimize the quantity of residual material remaining in the region of the application tube 14 situated between the valve seat 50 and the material outlet opening 28 after the closing of the needle valve 46.

(6) The first tube portion 18 and the second tube portion 24 may each be designed in one piece or, as shown in the exemplary embodiment, be composed of several components. In particular, the first tube portion 18, as illustrated in the drawing, may have a bush, which is disposed at a spacing from the ball joint 22 and in which the material inlet opening 20 is disposed.

(7) In summary, the following may be asserted: The invention relates to an apparatus 10 for application of a viscous material with an application tube 14 bounding an application duct 30 running in a longitudinal direction 16 from a material inlet opening 20 to a material outlet opening 28 and with a housing 12 that receives the application tube 14 at least partly and that has a material feed port 32 for the viscous material, wherein the application tube 14 has a first tube portion 18 disposed fixed to the housing and provided with the material inlet opening 20 and a second tube portion 24 adjoining the first tube portion 18 and provided at a free end 26 with the material outlet opening 28. According to the invention, a flexible joint 22 connecting the first tube portion 18 and the second tube portion 24 is provided, as is a drive unit 36 for deflection of the free end 26 of the second tube portion 24 in a transverse direction 34 oriented transversely relative to the longitudinal direction 16.