Method for producing a gasket on a component and shaping tool for use in such a method

Abstract

The invention relates to a method for producing a gasket on a component using a shaping tool, wherein the material used for the gasket is a UV-curable sealing or gasket material, and wherein the shaping tool comprises an upper face and a lower face and at least one cavity which is open toward the lower face of the shaping tool and which is provided for filling with the gasket material, and wherein furthermore the shaping tool is made of a UV-transparent material at least in the region of the cavity, comprising the following steps in the order indicated: 1. introducing the gasket material into the cavity of the shaping tool; 2. placing the component onto the lower face of the tool provided with the gasket material; 3. pressing the component onto the tool; 4. curing the gasket material by way of UV irradiation; and 5. removing the tool from the component and the gasket joined thereto. The invention further relates to a shaping tool for use in such a method.

Claims

1. A method for producing a gasket on a component, comprising: a. providing a UV-curable gasket material; b. providing a shaping tool including an upper face and a lower face and at least one cavity which is open toward the lower face of the shaping tool and which is provided for filling with the gasket material, and wherein the shaping tool is made of a UV-transparent material at least in the region of the cavity; c. introducing the gasket material into the cavity of the shaping tool; d. placing the component onto the lower face of the tool provided with the gasket material; e. pressing the component onto the tool; f. curing the gasket material by way of UV irradiation; and g. removing the tool from the component and the gasket joined thereto, wherein steps c to g are performed in the indicated order and the gasket material is introduced into the cavity of the shaping tool by an automated robotic system.

2. A method for producing a gasket on a component, comprising: a. providing a UV-curable gasket material; b. providing a shaping tool including an upper face and a lower face and at least one cavity which is open toward the lower face of the shaping tool and which is provided for filling with the gasket material, and wherein the shaping tool is made of a UV-transparent material at least in the region of the cavity; c. introducing the gasket material into the cavity of the shaping tool; d. placing the component onto the lower face of the tool provided with the gasket material; e. pressing the component onto the tool; f. curing the gasket material by way of UV irradiation; and g. removing the tool from the component and the gasket joined thereto, wherein steps c to q are performed in the indicated order and the step of introducing the gasket material into the cavity of the shaping tool comprises screen printing the gasket material into the cavity.

3. The method according to claim 1, wherein the shaping tool is made of a flexible material at least in the region of the cavity.

4. The method according to claim 1, wherein the shaping tool is made of silicone.

5. The method according to claim 1, wherein the shaping tool is made of a flexible material at least in the region of the cavity and is made of non-flexible material in some regions other than the cavity.

6. The method according to claim 1, wherein the gasket material comprises a UV-curable polyacrylate- or polyisobutylene-based material.

7. The method according to claim 1, wherein curing of the gasket material is carried out in a UV chamber or by use of UV LED fields.

8. A method for producing a gasket on a component, comprising: a. providing a UV-curable gasket material; b. providing a shaping tool including an upper face and a lower face and at least one cavity which is open toward the lower face of the shaping tool and which is provided for filling with the gasket material, and wherein the shaping tool is made of a UV-transparent material at least in the region of the cavity; c. introducing the gasket material into the cavity of the shaping tool; d. placing the component onto the lower face of the tool provided with the gasket material; e. pressing the component onto the tool; f. curing the gasket material by way of UV irradiation; and g. removing the tool from the component and the gasket joined thereto, wherein steps c to g are performed in the indicated order and curing of the gasket material is carried out using UV LEDs which are applied directly onto the shaping tool.

9. The method according to claim 1, wherein the shaping tool cavity has an opening directed toward the lower face and through which opening the cavity can be filled with a gasket material, and wherein other than the cavity, the shaping tool has no supply conduit that is open toward an edge of the shaping tool for supplying gasket material to the cavity.

10. The shaping tool according to claim 9, wherein an unbroken inner surface defines the cavity and there is no fluid connection through the wall to supply gasket material to the cavity.

11. The shaping tool according to claim 9, wherein the tool is made of a flexible material at least in the region of the cavity.

12. The shaping tool according to claim 9, wherein the shaping tool is made of a flexible material at least in the region of the cavity and is made of a non-flexible material in other regions.

13. The shaping tool according to claim 9, wherein UV LEDs are applied directly onto the shaping tool.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The invention will be described in more detail hereafter based on exemplary embodiments and with reference to the accompanying drawings. In the drawings:

(2) FIG. 1: shows a schematic sectional illustration of one embodiment of the shaping tool according to the invention;

(3) FIG. 2: shows a schematic sectional illustration of an alternative embodiment of the shaping tool according to the invention; and

(4) FIG. 3: shows a schematic illustration of the sequence of the method steps of the method according to the invention.

(5) FIG. 1 shows a sectional illustration of a shaping tool denoted by numeral 10, which is made entirely of silicone. The tool 10 has an upper face 11 and a lower face 12 as well as a circular cavity 13, which is open toward the lower face 12 of the tool 10.

(6) FIG. 2 shows an alternative embodiment of a shaping tool denoted in the overall by numeral 14. The tool 14 comprises a ring 15 made of silicone, in which a cavity 13 is formed analogously to the exemplary embodiment shown in FIG. 1. The silicone ring 15 is UV-transparent. The cavity 13 is open toward the lower face 12 of the tool 14. The silicone ring 15 is embedded in a stabilization aid 16 made of steel, wherein the silicone ring 15 has lateral recesses 17 in which projections 18 of the stabilization aid 16 engage according to the principle of a tongue-and-groove joint, whereby a relative movement of the silicone ring 15 and the stabilization aid 16 is prevented.

(7) A ring made of UV LEDs 19 is arranged above the silicone ring 15, the LEDs emitting UV radiation in a wavelength range between 200 and 550 nm. A clamp 20 is guided across the UV LEDs and the central core of the stabilization aid 16 so as to fix the UV LEDs and the individual components of the tool 14, the clamp being fixed to the stabilization aid 16 in an edge region of the tool 14 by way of screws 21.

(8) The tool 14 shown only in a sectional view in FIG. 2 has an approximately square outer shape. The silicone ring 15 embedded in the stabilization aid is likewise guided in the shape of a square having rounded edges, and accordingly the cavity 13 also follows this shape. It goes without saying that both the tool 14 and the silicone ring 15, and the cavity 13 formed therein, can also have any other shape, for example that of a circle or an ellipse.

(9) FIG. 3 shows a schematic illustration of the sequence of the individual method steps for carrying out a method for producing a gasket on a component using a shaping tool according to FIGS. 1 and 2. A specific sequence of the method for using the tool 14 of FIG. 2 may be as follows: In a step 1, initially a polyacrylate-based sealing material is introduced into the cavity 13 of the shaping tool 14 using a screen printing method. For this purpose, the tool 14 is turned 180 in relation to the illustration in FIG. 2, so that the lower face 12 of the tool 14 is directed upward with the open cavity 13. The sealing material is applied through a suitably-prepared screen, pressed through the screen by way of a squeegee and introduced into the cavity 13. This method step is repeated until the cavity 13 is filled completely with the sealing material.

(10) According to method step 2, the component to be sealed, which is not shown in the figures, is then placed onto the lower face 12 of the tool 14 provided with the sealing material and, in accordance with method step 3, is pressed onto the tool 14.

(11) In the subsequent method step 4, the UV LEDs 19 provided on the tool 14 are switched on, and the sealing material is cured by way of UV irradiation. Due to the UV transmissibility of the silicone ring 15, the UV radiation can readily enter the region of the cavity 13 and initiates the curing mechanism in the sealing material there. The duration of irradiation depends on the amount of sealing compound to be cured. For sealing heights in the range of 0.2 to 1 mm, curing takes place within a few seconds.

(12) After curing has been completed, the tool 14 is removed from the component to be sealed and the gasket joined to the same in a last method step 5. This is readily possible due to the good release action of the silicone with respect to the polyacrylate-based sealing material.

(13) In principle, the method according to the invention makes higher process speeds possible than with the conventional injection molding method since the filling process and the curing process can be separated from each other. By eliminating the injection unit, moreover the tool and process costs can be lowered. Finally, it is possible to avoid inaccuracies in the geometry of the gasket to be produced, which necessarily occur in the injection molding method due to the injection pressure that is required and since the alignment between the tool and the component is not always optimal.