Method and tool for the automated production and placement of double-sided self-adhesive adhesive pads

Abstract

A method for the automated production of an adhesive plate (1) from a double-sided self-adhesive material sheet (2) and placing the adhesive plate (1) on a workpiece (4) by means of a tool (3) which has a chamber (6) open on one side with chamber side walls (7), with a chamber base designed as a flat perforated plate (8) and with an opening edge (9) designed as a cutting contour, wherein the distance (D) between the flat perforated plate (8) and the opening edge (9) corresponds at most to the thickness (d) of the material sheet (2), comprises the following method steps: - providing a double-sided self-adhesive material sheet (2) held self-adhesively on a base (5); - lowering (11) the tool (3) onto the material sheet (2) until the opening edge (9) rests on the base (5) in order to cut out an adhesive plate (1);- Lifting (13) the tool (3) from the base (5) in order to detach the adhesive pad (1), which is now self-adhesively held to the flat perforated wall (8) and to the chamber side walls (7), from the base (5);- Moving (14) the tool (3) together with the adhesive pad (1) which is self-adhesively held to it, to a workpiece (4);- Lowering (15) the tool (3) onto the workpiece (4) until the adhesive pad (1) is in contact with the workpiece (4) or is less than its thickness (d) away from the workpiece (4);- Applying an overpressure (16) to the back of the flat perforated plate (8) in order to press the adhesive pad (1) which is in contact with the workpiece (4) further against the workpiece (4), whereby the adhesive pad (1) is held self-adhesively to the workpiece (4); and- lifting (17) the tool (3) from the workpiece (4) in order to detach the adhesive pad (1) held self-adhesively on the workpiece (4) from its self-adhesive contact with the perforated plate (8) and the side walls (7);

Description

[0001] The present invention relates to a method for the automated production of an adhesive plate, in particular a square one, from a double-sided self-adhesive material sheet and placing the cut-out adhesive plate on a workpiece, as well as a tool suitable for carrying out this method.

[0002] Today, the demand for higher-performance, more functional electronic devices continues to grow exponentially. The associated increase in power consumption and heat generation is increasingly impacting the overall performance and longevity of electronic devices. Efficient thermal management is therefore essential to maintain the optimal operating temperature of electronic devices, thereby ensuring their performance reliability and extending their service life.

[0003] Thermal interface materials (TIMs) play a critical role in heat transfer between two solid surfaces, especially between an electronic component and a heat sink. The following thermal interface materials are currently in use: Thermal paste (also known as thermal compound or thermal grease) is a viscous substance that fills microscopic voids between the surfaces of electronic components and heat sinks. The high thermal conductivity of thermal paste helps improve heat transfer by minimizing air gaps and increasing surface contact. Thermal paste is typically used where a thin, continuous layer of material is required for optimal cooling performance. Thermal pads are preformed from solid material and are available in various thicknesses and degrees of softness. These thermal pads provide mechanical fit and electrical insulation, as well as thermal conductivity, between two components. They are used where large gaps or non-uniform surfaces need to be filled. Thermal pads enable simple, mess-free installation and are often preferred for their ease of handling and reworkability. Thermally conductive gap fillers are specially formulated materials used to fill irregular gaps between electronic components and heat sinks. They are known for their high conformability and elasticity, allowing them to fill large gaps and surface variations. Thermally conductive gap fillers are typically soft, compliant, and available in various forms, such as dispensable gels or compressible pads. They are used where there are significant height differences or surface irregularities, requiring customization for optimal thermal management.

[0004] Each of these thermal interface materials offers different advantages depending on the specific requirements of the electronic application. The selection of the appropriate material depends on various factors, such as surface topography, gap spacing, reworkability requirements, and the desired level of thermal conductivity. Understanding the unique properties and applications of thermal paste, thermal pads, and thermally conductive gap fillers can help ensure efficient heat dissipation and reliable performance.

[0005] The invention is based on the object of producing small thermally conductive gap fillers in the form of thin, double-sided self-adhesive adhesive pads made of soft and sticky material and placing them on a workpiece, as well as providing a suitable tool for this purpose.

[0006] This object is achieved according to the invention by a method having the method steps of claim 1.

[0007] According to the invention, a double-sided self-adhesive sheet of material is provided which is held self-adhesively to a base (e.g., a plastic base). The sheet of material is formed from a material which, for example, has a kneading properties similar to modeling clay or cookie dough, and has a uniform material thickness. The adhesive pads must be cut out of the sheet of material to the desired dimensions and placed on a workpiece. However, lifting a thin, very soft, and sticky adhesive pad from the base represents a technical challenge due to the interplay of several factors. The inherent nature of the material—namely, its thinness, softness, and adhesive properties—complicates both the separation of an individual adhesive pad from the rest of the sheet of material and the subsequent lifting of the adhesive pad from the base.The sticky material sheet adheres to the substrate with such high adhesion forces that it is very difficult to remove the adhesive pad from the substrate.

[0008] In addition, the thinness of the material sheet means it can easily be deformed or destroyed by external removal forces. Therefore, careful and precise handling is required to prevent tearing or deformation of the adhesive pad, thus preserving the integrity and functionality of the material. The softness of the material increases the likelihood of deformation or wrinkling during removal of the adhesive pad from the substrate. The lack of structural rigidity makes it difficult to achieve a uniform and controlled removal of the adhesive pad, leading to inaccuracies and problems during removal.

[0009] Furthermore, the high tackiness or adhesiveness of the material exacerbates the bond between the material sheet and its substrate. The cohesive forces acting between them require a nuanced and specialized approach to ensure clean and precise separation of the adhesive pad without leaving any residue or damaging the material sheet or substrate.

[0010] According to the invention, a tool having a chamber open on one side with chamber side walls, a chamber floor designed as a perforated plate and an opening edge designed as a cutting contour is lowered onto the material sheet until the opening edge rests on the base and an adhesive pad is thereby cut out of the material sheet. The tool is lifted from the base in order to detach the adhesive pad, which is now self-adhesively held to the chamber side walls and the flat perforated wall, from the base. The tool, together with the adhesive pad held self-adhesively to it, is then moved to the workpiece (e.g. an electrical component or a heat sink) and lowered onto it until the adhesive pad is in contact with the workpiece or almost in contact, i.e. is less than its thickness away from the workpiece. Subsequently, an overpressure, e.g.Compressed air is applied to the back of the flat perforated plate to either press the adhesive pad still in contact with the workpiece further against the workpiece or to push the adhesive pad still removed from the workpiece out of the chamber and against the workpiece, thereby self-adhering the adhesive pad to the workpiece. Finally, the tool is lifted from the workpiece to detach the adhesive pad, which is self-adhering to the workpiece, from its self-adhering contact with the side walls and the perforated plate. As a result, the adhesive pad is placed on the workpiece and self-adhering to it.

[0011] The method according to the invention thus enables the placement of small self-adhesive adhesive pads, which are similarly sticky to modeling clay, (cookie) dough or plasticine and are really difficult to handle, as spacers on the workpiece and ultimately for thermal insulation.

[0012] Preferably, a vacuum is applied to the back of the flat perforated plate while the tool is being lifted from the base to further press or suction the adhesive pad against the flat perforated plate. This increases the holding force between the adhesive pad and the perforated plate, ensuring the adhesive pad is securely removed from the base.

[0013] In one process variant, a vacuum is applied to the back of the flat perforated plate while the tool is moving to increase the holding force. In another process variant, if the adhesive force with which the adhesive pad is held self-adhesively to the flat perforated plate is greater than the weight of the adhesive pad, no vacuum needs to be applied to the back of the flat perforated plate while the tool, including the adhesive pad, is moved toward the workpiece.

[0014] Optionally, a vacuum can be applied to the back of the flat perforated plate before the tool pierces the material sheet with its opening edge.

[0015] Preferably, the negative or positive pressure prevailing in the chamber is as uniform as possible across the entire opening cross-section of the chamber opening in order to suck in and eject the adhesive pad as plane-parallel as possible to the flat perforated plate. For this purpose, the perforated plate can, for example, have a sufficient number of holes evenly distributed across the opening cross-section of the chamber so that a uniform or gradient-free negative or positive pressure is generated in the chamber across the opening cross-section. The size, number, and position of the holes are selected so that the soft adhesive pad is not sucked into the holes. The holes can advantageously be arranged in a matrix.

[0016] The double-sided self-adhesive material sheet is preferably less than or equal to 2 mm thick, particularly preferably approximately 1 mm thick, and preferably formed from a thermally insulating, modeling clay-like or (cookie) dough-like sticky material, such as a silicone-based, thermally conductive gap filler (silicon-based thermal interface gap filler).

[0017] The invention also relates to a tool suitable for carrying out the method according to the invention having the features of claim 10.

[0018] For example, the tool may have a single port that can be connected to either a vacuum or a positive pressure source, or two parallel ports, one of which can be connected to a vacuum source and the other to a positive pressure source.

[0019] Preferably, the perforated plate has a plurality of holes, in particular of equal size, which can be arranged, for example, evenly distributed, in particular in matrix form, over the opening cross-section of the chamber.

[0020] Particularly advantageously, the tool can comprise a tool body and a detachably mounted tool attachment, which forms at least the opening edge. This eliminates the need to replace the entire tool; instead, a tool attachment with a worn opening edge can be cost-effectively replaced with a new tool attachment with the same, but sharp opening edge. Furthermore, for a different cutting contour, the entire tool does not need to be replaced; instead, only the tool attachment with a differently contoured opening edge needs to be replaced cost-effectively.

[0021] Further advantages and advantageous embodiments of the subject matter of the invention can be found in the description, the drawings, and the claims. Likewise, the features mentioned above and those listed below can be used individually or in combination in any desired manner. The embodiments shown and described are not to be understood as an exhaustive list, but merely as examples for describing the invention.

[0022] They show: Fig. 1a-1h show the process steps of the method according to the invention for the automated production and placement of double-sided self-adhesive adhesive pads by means of a tool; Fig. 2a, Fig. 2b that in Fig. 1 tool shown in a view from below ( Fig. 2a) and in a perspective partial view ( Fig. 2b); and Fig. 3a, Fig. 3b a modified tool in a side view (3a) and in a perspective view ( Fig. 3b).

[0023] Fig. 1 shows the method steps for the automated production of an adhesive plate 1 from a double-sided self-adhesive material sheet 2 by means of a tool 3 and for placing the adhesive plate 1 on a workpiece 4 by means of the tool 3. The material sheet 2 is held self-adhesively on a base 5 (e.g. made of plastic) and has a thickness d which is preferably less than or equal to 2 mm, preferably approximately 1 mm.

[0024] As in Fig. 2a, Fig. As shown in Figure 2b, the tool 3 has a chamber 6 that is open on one side, here downwards, with chamber side walls 7, a chamber base designed as a flat perforated plate 8, and an opening edge 9 designed as a cutting contour. The distance D between the flat perforated plate 8 and the opening edge 9 corresponds at most to the thickness d of the material sheet 2 and is preferably smaller than the thickness d. The perforated plate 8 has a plurality of holes 10, in particular of equal size, which can be arranged evenly across the opening cross-section of the chamber 6, for example.

[0025] The individual process steps for the automated production and placement of the adhesive plate 1 are as follows.

[0026] The double-sided self-adhesive material sheet 2, which is held self-adhesive on the base 5, is provided ( Fig. 1a).

[0027] The tool 3 is lowered onto the material sheet 2 (arrow 11) until the opening edge 9 rests on the base 5, whereby an adhesive plate 1 is cut out in the material sheet 2 ( Fig. 1b). The adhesive pad 1 is now also self-adhesively held to the flat perforated wall 8 and to the chamber side walls 7. Optionally, a vacuum 12 can be applied to the back of the flat perforated plate 8 ( Fig. 1c) to additionally press or suck the adhesive pad 1 against the flat perforated plate 8. The negative pressure 12 can also be applied before the opening edge 9 penetrates the material sheet 2.

[0028] The tool 3 is then lifted from the base 5 (arrow 13), whereby the adhesive plate 1 is detached from the base 5 because it is held self-adhesively on the flat perforated wall 8 and on the chamber side walls 7 ( Fig. 1d). Optionally, the negative pressure 12 can also be applied during the lifting of the tool 3 in order to increase the holding force of the adhesive plate 1 on the flat perforated plate 8.

[0029] The tool 3 together with the adhesive pad 1 held to it is now moved above the workpiece 4 (double arrow 14) ( Fig. 1e). The tool 3 is then lowered onto the workpiece 4 (arrow 15) until the adhesive pad 1 rests against the workpiece 4 ( Fig. 1f) or almost so, ie it is less than its thickness d away from the workpiece.

[0030] An overpressure 16 is applied to the back of the flat perforated plate 8, whereby either the adhesive plate 1 resting on the workpiece 4 is pressed away from the perforated plate 8 and against the workpiece 4 ( Fig. 1g) or the adhesive pad 1 still removed from the workpiece 4 is pressed out of the chamber 6 and against the workpiece 4 in order to hold the adhesive pad 1 self-adhesively to the workpiece 4.

[0031] Finally, the tool 3 is lifted off the workpiece 4 (17), whereby the adhesive plate 1, which is held self-adhesively on the workpiece 4, is detached from its self-adhesive attachment to the tool 3, i.e. from the perforated plate 8 and from the chamber side walls 7 ( Fig. 1h). As a result, the adhesive pad 1 is placed on the workpiece 4 and held there self-adhesively.

[0032] As in Fig. As shown in Figure 1, the tool 3 has a channel 18 extending to the rear of the flat perforated plate 8, which at the other end opens into a connection 19, here on the top. The connection 19 is connected either to a vacuum or to a positive pressure source (not shown) in order to generate the negative or positive pressure 12, 16 at the rear of the flat perforated plate 8.

[0033] From tool 3 of the Fig. 1 and Fig. 2 differs in Fig. 3a, Fig. Tool 3 shown in Figure 3b is distinguished by the fact that here the connection 19 is connected to a vacuum source, for example, via a 3 / 2-way valve (not shown). A further channel 20 opens laterally into the channel 18, with a connection 21, also located on top here, which is connected to a pressure source via the 3 / 2-way valve. By switching the 3 / 2-way valve, negative or positive pressure 12, 16 is generated on the rear side of the flat perforated plate 8.

[0034] As in Fig.3b, the tool 3 comprises a tool base body 22 and a tool attachment 23 detachably mounted thereon, which forms at least the opening edge 9. This makes it possible to replace a tool attachment 23 with a worn opening edge 9 with a new tool attachment 23 with the same, but sharp opening edge 9 or with a tool attachment 23 with a different cutting contour. As shown, the tool attachment 23 can be placed onto the tool base body 22 and detachably fixed thereto by means of a screw 24 or another solution known in the prior art.

Claims

[1] Method for the automated production of an adhesive plate (1) from a double-sided self-adhesive material sheet (2) and placing the adhesive plate (1) on a workpiece (4) by means of a tool (3) which has a chamber (6) open on one side with chamber side walls (7), with a chamber base designed as a flat perforated plate (8) and with an opening edge (9) designed as a cut-out contour, wherein the distance (D) between the flat perforated plate (8) and the opening edge (9) corresponds at most to the thickness (d) of the material sheet (2), with the following method steps: - Providing a double-sided self-adhesive material sheet (2) held self-adhesively on a base (5); - lowering (11) the tool (3) onto the material sheet (2) until the opening edge (9) rests on the base (5) in order to release an adhesive pad (1); - Lifting (13) the tool (3) from the base (5) in order to detach the adhesive plate (1), which is now held self-adhesively on the flat perforated wall (8) and on the chamber side walls (7), from the base (5); - moving (14) the tool (3) together with the adhesive pad (1) held thereon in a self-adhesive manner to a workpiece (4); - lowering (15) the tool (3) onto the workpiece (4) until the adhesive pad (1) rests against the workpiece (4) or is less than its thickness (d) away from the workpiece (4); - applying an overpressure (16) to the back of the flat perforated plate (8) in order to press the adhesive plate (1) resting on the workpiece (4) against the workpiece (4), whereby the adhesive plate (1) is held self-adhesively to the workpiece (4); and - Lifting (17) the tool (3) from the workpiece (4) in order to detach the adhesive pad (1) held self-adhesively on the workpiece (4) from its self-adhesive contact with the perforated plate (8) and the side walls (7). [2] Method according to claim 1, characterized by that during the lifting (13) of the tool (3) from the base (5) a negative pressure (12) is applied to the back of the flat perforated plate (8) in order to additionally press the adhesive plate (1) against the flat perforated plate (8). [3] Method according to claim 1 or 2, characterized by that during the movement (14) of the tool (3) towards the workpiece (4) a negative pressure (12) is applied to the back of the flat perforated plate (8). [4] Method according to claim 1 or 2, characterized by that the adhesive force with which the adhesive plate (1) is held self-adhesively to the flat perforated plate (8) is greater than the weight of the adhesive plate (1) and that, while the tool (3) together with the adhesive plate (1) is moved towards the workpiece (4), no negative pressure is applied to the back of the flat perforated plate (8). [5] Method according to one of the preceding claims, characterized bythat, before the opening edge (9) pierces the material sheet (2), a negative pressure (12) is applied to the back of the flat perforated plate (8). [6] Method according to one of the preceding claims, characterized by that the negative or positive pressure (12,16) prevailing in the chamber (6) is the same across the entire opening cross-section of the chamber (6). [7] Method according to one of the preceding claims, characterized by that the workpiece (4) is an electrical component or a heat sink. [8] Method according to one of the preceding claims, characterized by that the thickness (d) of the double-sided self-adhesive material sheet (2) is less than or equal to 2 mm, preferably approximately 1 mm. [9] Method according to one of the preceding claims, characterized by that the double-sided self-adhesive material sheet (2) is made of a thermally insulating, plasticine-like or dough-like sticky material. [10] Tool (3) for producing an adhesive pad (1) from a double-sided self-adhesive material sheet (2) and placing the adhesive pad (1) on a workpiece (4), with a chamber (6) open on one side, which has chamber side walls (7), a chamber bottom designed as a flat perforated plate (8) and an opening edge (9) designed as a cut-out contour, with a channel (18) which at one end reaches the rear of the flat perforated plate (8), and with at least one connection (19, 21) to which the channel (18) is connected at the other end. [11] Tool according to claim 10, characterized by a single connection (19) which can be connected to either a negative pressure or a positive pressure source. [12] Tool according to claim 10, characterized by two parallel connections (19, 21), one of which connection (19) can be connected to a negative pressure source and the other connection (20) can be connected to a positive pressure source (19). [13] Tool according to one of claims 10 to 12, characterized by that the perforated plate (8) has several holes (10), in particular of equal size. [14] Tool according to claim 13, characterized by that the holes (10) are distributed uniformly, in particular in matrix form, over the opening cross-section of the chamber (6). [15] Tool according to one of claims 10 to 14, characterized by that the tool (3) has a tool base body (22) and a tool attachment (23) detachably mounted thereon, which forms at least the opening edge (9).

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