METHOD FOR COVERING A SCREW HEAD IN A SEALED MANNER

Abstract

A method for covering a screw head of a screw which penetrates through a workpiece surface in a sealed manner by means of a viscous coating material is disclosed. The method includes the steps of applying a first strip of the viscous coating material onto the workpiece surface at a first inclination relative to the workpiece surface, the first strip of the viscous coating material, after having been applied, at most partially covering the screw head; and applying a second strip of the viscous coating material to the workpiece surface at a second inclination relative to the workpiece surface, the second strip of the viscous coating material, after having been applied, overlapping the first strip in such a way that the screw head is fully covered, the first inclination and the second inclination being opposite one another. The invention furthermore relates to an application system.

Claims

1. A method for covering a screw head of a screw which penetrates through a workpiece surface with a viscous coating material, the method comprising the steps of: applying a first strip of the viscous coating material onto the workpiece surface at a first inclination relative to the workpiece surface, the first strip of the viscous coating material, after having been applied, at most partially covering the screw head; and applying a second strip of the viscous coating material to the workpiece surface at a second inclination, the second strip of the viscous coating material, after having been applied, overlapping the first strip in such a way that the screw head is fully covered; and wherein the first inclination and the second inclination are arranged opposite to one another.

2. The method according to claim 1, wherein the steps of applying further comprise continuously moving a nozzle adapted to spray the viscous coating material.

3. The method according to claim 2, wherein the application of the first strip and the application of the second strip are carried out with opposite application directions of the nozzle.

4. The method according to claim 1, wherein the application of the second strip takes place within at least one of a drying time of the viscous coating material and before a skin has formed on the first strip.

5. The method according to claim 1, wherein the workpiece comprises a battery housing including battery modules arranged in the battery housing.

6. The method according to claim 1, wherein the first inclination and the second inclination are each 5° from an orthogonal orientation relative to the workpiece surface.

7. The method according to claim 1, wherein the partial coverage during application of the first strip comprises at least one of at least 50% of the surface of the screw head and up to 60% of the surface of the screw head.

8. The method according to claim 1, wherein when applying the second strip, the overlap comprises at least 10% of the first strip.

9. The method according to claim 1, further comprising the steps of providing at least one of the viscous coating material and a two-component material as a viscous coating material.

10. The method according to claim 1, further comprising the steps of optically detecting the application by a camera, and correcting the application if it is detected that the application deviates from a desired path.

11. The method according to claim 1, further comprising the steps of defining an application path, the application path having a length, wherein a drying time of the viscous coating material and an application speed are taken into account when defining the application path.

12. An application system for covering a screw head of a screw which penetrates through a workpiece surface in a sealed manner by means of a viscous coating material, the system comprising: an application head adapted to apply the viscous coating material to the workpiece surface in a first strip under a first inclination with respect to the workpiece surface and in a second strip under a second inclination with respect to the workpiece surface, the first inclination and the second inclination being opposite to each other; and a controller arranged and configured to adjust the first inclination and the second inclination and to actuate the application head such that, when the first strip of the viscous coating material is applied, the screw head is at most partially covered and, when the viscous coating material is applied to the workpiece surface, the second strip of the viscous coating material overlaps the first strip after application in such a way that the screw head is completely covered.

13. The application system according to claim 12, wherein the application head comprises a nozzle and two ports, wherein the two ports are configured to be connected to different containers and are adapted to convey two components of a two-component material to the nozzle.

14. The application system according to any claim 12, wherein the controller 243 is further configured to relate the first inclination and the second inclination to a lot to the workpiece surface.

15. The application system according to claim 12, wherein the controller is configured to determine a length of the first strip as a function of a drying time of the viscous coating material and a speed of the application head.

Description

[0055] In the following, the invention is described in more detail with reference to examples of embodiments and the figures. Showing in:

[0056] FIG. 1a a schematic representation of an arrangement;

[0057] FIG. 1b, a further schematic representation of the arrangement according to FIG. 1a;

[0058] FIG. 1c, a schematic representation of an arrangement according to FIG. 1b with a coating;

[0059] FIG. 2a a schematic representation of an arrangement with an application system according to one embodiment;

[0060] FIG. 2b a further schematic representation of the arrangement in FIG. 2a;

[0061] FIG. 3a a schematic representation of an arrangement according to an embodiment example;

[0062] FIG. 3b a further schematic representation of the arrangement according to FIG. 3a;

[0063] FIG. 3c a further schematic representation of the arrangement according to FIG. 3b; and

[0064] FIG. 4 a flowchart for a process according to an embodiment.

[0065] In the following detailed description, reference is made to the accompanying drawings which form a part hereof and which are shown, by way of illustration, specific embodiments in which the invention may be carried out. It is understood that other embodiments may be used and structural or logical changes may be made without deviating from the concept of the present invention. Therefore, the following detailed description is not to be understood in a restrictive sense. It is further understood that the characteristics of the various embodiments described herein may be combined, unless specifically stated otherwise.

[0066] The aspects and embodiments are described by reference to the drawings, with the same reference signs generally referring to the same elements. The following description sets out a number of specific details to provide an in-depth understanding of one or more aspects of the invention. However, it may be obvious to a skilled person that one or more aspects or embodiments can be carried out with a lower degree of specific detail. In other cases, known structures and elements are shown in a schematic form to facilitate the description of one or more aspects or embodiments. It is understood that other embodiments may be used and structural or logical changes may be made without deviating from the concept of the present invention.

[0067] FIG. 2a shows a schematic representation of an arrangement 200 with an application system 201 according to an embodiment. The arrangement 200 shows a workpiece 203 with a screw 205 having a screw head 207. The screw head 207 substantially rests on a workpiece surface 209. However, in such a connection, it may happen that, for example, due to tolerances, the contact of the screw head 207 on the workpiece surface 209 does not occur completely and/or does not seal the screw 205 securely. In this case, moisture could penetrate through the workpiece 203. The workpiece 203 in this case is a housing of a battery. In a further embodiment, the workpiece 203 is a different housing, which is intended to protect against moisture in particular. The workpiece 203 may have a section to be sealed of, for example 11m in length, resulting from a plurality of individual sections which are arranged on an edge around the housing. For example, the battery may have a width of 1.2 m and a length of 2.3 m with a thickness of 15 cm. In further embodiments, the values may differ.

[0068] The application system 201 comprises a nozzle 211 and a controller 213. The nozzle 211 is configured to mix and spray a two-component material and thereby apply it to the workpiece 203. The controller 213 is adapted to control the nozzle 211 and to control a movement of the nozzle 211. In the embodiment shown, the application system 201 is movable. In another embodiment example, the nozzle 211 is movable and the controller 213 is not. The controller 213 can be centrally arranged and, in particular, integrated into a computer system.

[0069] The nozzle 211 may be a flat nozzle to produce a flat spray stream, a FlatStream. In particular, the nozzle 211 may have a 3 mm thick gap of 1 cm in length. Through this, a two-component material can be introduced at about 100 bar. The nozzle 211 has a screw-shaped mixing tube, a helix for mixing with, in particular, 24 turns, at the end of which there is a pressure of approx. 30 to 40 bar.

[0070] In FIG. 2a an orthogonal 215 to the workpiece surface 209 is drawn and a first inclination 217, which is at a first angle 219 to the orthogonal 215. In this case, the first angle 219 is 5°. In another embodiment, the first angle 219 is a different value, in particular more than 5° to the orthogonal 215. The application system 201 may apply a viscous coating material at the first angle 219, i.e. spray it laterally to the screw head 207. A first strip is formed, in particular during a forward movement of the nozzle 211.

[0071] FIG. 2b also shows, as described with respect to FIG. 2a, the arrangement 200 with the workpiece 203 and the application system 201. A viscous coating material 221 was applied as the first strip during the forward movement. The first strip of the viscous coating material 221 covers 50%. of the screw head 207. In another embodiment, the covering is more or less, in particular between 50% and 60% of the surface of the screw head 207.

[0072] The nozzle 211 is inclined in a second inclination 223, that is, arranged at a second angle 225 to the orthogonal with respect to the workpiece surface 209. The second angle 225 is also 5°.

[0073] In a further embodiment, the second angle 225 has a different value, in particular a different value than the first angle 219, and in particular a smaller value than the first angle 219. The second inclination 223 is arranged with respect to the orthogonal 215 with respect to the workpiece surface 209 on a side opposite to the first inclination 217, with respect to an application direction. Thus, when the viscous coating material 221 is applied for the second time, the rest of the screw head 207 can be completely covered.

[0074] In another embodiment example, the first angle is 219 and/or the second angle 225 is 0°. This is particularly dependent on component accessibility. For example, if an inclination of the nozzle 211 of 5° is not possible when applying the second strip, because components of the workpiece 203 are in the way, the application can also be carried out completely or partially at an angle of 0°. Regardless of the inclination when applying the first strip, the screw head 207 is at most partially covered when applying the first strip and the screw head 207 is completely covered by applying the second strip.

[0075] FIG. 3a shows a workpiece 301 with two screw heads 303. An arrow 305 is drawn to indicate a first direction along which the first path is to be coated.

[0076] FIG. 3b shows the state of the workpiece 301 with the two screw heads 303 as the first strip after the first application of the viscous coating material 221. The bolt heads 303 are half covered. Arrow 307 marks a second direction along which the second path is to be coated.

[0077] FIG. 3c shows the state of the workpiece 301 with the two screw heads 303 as second strip after the first application of the viscous coating material 221. The bolt heads 303 are completely covered. In particular, the viscous coating material 221 is applied uniformly in the area of the screw heads 303 as well as between the screw heads 303.

[0078] FIG. 4 shows a flow diagram 400 for a process according to an embodiment.

[0079] In a step 401, a viscous coating material 221 is provided. Here, a two-component material is provided, in particular in two separate containers, which are connected to the nozzle 211 by supply lines. The nozzle 211 comprises a screw structure that allows uniform mixing of the two components. In another embodiment, a viscous coating material 221 consisting of a component is used.

[0080] In a step 402, an application path is defined. Here, a path may be defined in the control system 213 via coordinates and/or vectors for the nozzle 211 of the application system 201. This may be done separately for each workpiece 203 to be coated. In another embodiment, the application path is determined by the control system 213 based on camera data, which comprises an evaluation of detected screw heads 303.

[0081] In all cases, by comparing the programmed first strip and the programmed second strip with camera data, a deviation from the respective strip can be detected and corrected during application, i.e., when the first web or the second web is run. In another embodiment, this is omitted. Tolerances can be selected to be larger, i.e., the application of the first strip and/or the application of the second strip can be made wider.

[0082] In one step, 403, the viscous coating material 221 is applied as the first strip with the first inclination 217. The screw heads 303 are at most partially covered by the viscous coating material 221 in particular 50% to 60%. The application direction is carried out in a forward movement of the nozzle 211.

[0083] In one step 404, the viscous coating material 221 is applied as a second strip with the second inclination 223. The screw heads 303 are completely covered by the viscous coating material 221. That is, the rest of the screw head 303, which is not covered by the first strip viscous coating material 221, is covered. In particular, the first strip overlaps with the second strip. The application direction is carried out in a backward movement of the nozzle 211, which runs opposite to the forward movement. In another embodiment, the order of the first strip and the order of the second strip are carried out in the same direction. In particular, the application in step 403 and the application in step 404 takes 30 seconds each. In another example, the time is different. This can be determined by the control system 213 based on the drying time of the viscous coating material 221 and the application speed, that is, the speed with which the nozzle 211 is movable. Thus, no skin has formed on the first path when the second path is sprayed over the first path and the first path and the second path can mix together.

[0084] The application in steps 403 and 404 can be detected and evaluated by a camera. Here, errors and tolerances can be reacted to. That is, the control system 213 can adjust the nozzle 211 accordingly, in order to achieve a compensation and to enable a similar order.

[0085] In a step 405, the tightness of the application is checked. For this purpose, an overpressure is applied to the workpiece 203 with the applied viscous coating material 221. If the pressure holds the same value for a predetermined time, the connection is tight. In another embodiment, a negative pressure is applied.

LIST OF REFERENCES

[0086] 101,205 screw [0087] 103 cover/lid [0088] 105, 207, 303 screw head [0089] 107 surface [0090] 109 coating material [0091] 111 air duct [0092] 200 arrangement [0093] 201 application system [0094] 203, 301 workpiece [0095] 209 workpiece surface [0096] 211 nozzle [0097] 213 control/controller [0098] 215 orthogonal [0099] 217 first inclination [0100] 219 first angle [0101] 221 coating material [0102] 223 second inclination [0103] 225 second angle [0104] 305, 307 arrow [0105] 400 flow diagram/flowchart [0106] 401-405 application/process step