METHOD FOR PRODUCING A HYBRID COMPONENT

Abstract

A method for producing a hybrid component may include placing a metallic insert part into an injection mould, at least one of over-moulding and back-injecting the metallic insert part with a plastic mass, and pretreating a surface of the metallic insert part that is to be at least one of over-moulded and back-injected prior to the at least one of over-moulding and back-injecting. The metallic insert part may be placed into the injection mould such that the metallic insert part protrudes from the plastic mass on at least one side. A material accumulation may be disposed on a transition region from the metallic insert part to the plastic mass.

Claims

1. A method for producing a hybrid component, comprising: placing a metallic insert part into an injection mould; at least one of over-moulding and back-injecting the metallic insert part with a plastic mass; pretreating a surface of the metallic insert part that is to be at least one of over-moulded and back-injected prior to the at least one of over-moulding and back-injecting; wherein the metallic insert part is placed into the injection mould such that the metallic insert part protrudes from the plastic mass on at least one side; and wherein a material accumulation is disposed on a transition region from the metallic insert part to the plastic mass.

2. The method according to claim 1, wherein pretreating the surface of the metallic insert part includes at least one of cleaning and degreasing the surface to be at least one of over-moulded and back-injected.

3. The method according to claim 1, wherein the metallic insert part is configured as at least one of a casting, a ceramic part, an aluminium part, a sintered part, and a sheet metal part.

4. The method according to claim 1, wherein at least one of the plastic mass and the material accumulation includes a thermosetting plastic.

5. The method according to claim 1, wherein pretreating the surface of the metallic insert part includes roughening the surface to be at least one of over-moulded and back-injected.

6. The method according to claim 1, wherein the metallic insert part is at least one of pickled, ground, polished, blasted and chrome-plated on the surface to be at least one of over-moulded and back-injected prior to the at least one of over-moulding and back-injecting.

7. The method according to claim 1, wherein pretreating the surface of the metallic insert part includes plasma-treating and subsequently coating the surface to be at least one of over-moulded and back-injected.

8. The method according to claim 1, wherein the surface to be at least one of over-moulded and back-injected includes a plurality of honeycomb-like recesses with a depth of 0.1 mm to 0.3 mm.

9. The method according to claim 1, wherein the metallic insert part includes a plurality of cut-outs.

10. The method according to claim 1, wherein the metallic insert part protrudes from the plastic mass at an angle of 60° to 90°.

11. A hybrid component, produced according to the method of claim 1.

12. The hybrid component according to claim 11, wherein: the hybrid component is a cylinder head cover; and the metallic insert part is a guide for a pump tappet.

13. The method according to claim 1, wherein the metallic insert part is a non-hollow component.

14. The method according to claim 1, wherein the metallic insert part is a hollow component.

15. The method according to claim 1, wherein the surface to be at least one of over-moulded and back-injected includes a plurality of cut-outs.

16. The method according to claim 1, wherein pretreating the surface of the metallic insert part includes: plasma-treating the surface to be at least one of over-moulded and back-injected; and after plasma-treating the surface, coating the surface to be at least one of over-moulded and back-injected with a DLC coat.

17. A method for producing a hybrid component, comprising: placing a metallic insert part into an injection mould; pretreating a surface of the metallic insert part; at least one of over-moulding and back-injecting at least the treated surface of the metallic insert part with a plastic mass; wherein placing the metallic insert part into the injection mould includes arranging the metallic insert part in the injection mould such that, after the at least one of over-moulding and back-injecting, the metallic insert part protrudes from the plastic mass on at least one side; and wherein at least one of over-moulding and back-injecting the metallic insert part includes forming a material accumulation in a transition region from the metallic insert part to the plastic mass.

18. The method according to claim 17, wherein the material accumulation is integrally formed with the plastic mass.

19. The method according to claim 17, wherein: the surface of the metallic insert part includes at least one cut-out; and at least one of over-moulding and back-injecting the metallic insert part further includes connecting the metallic insert part and the plastic mass via passing at least a portion of the plastic mass through the at least one cut-out of the treated surface.

20. The method according to claim 17, wherein at least one of over-moulding and back-injecting the metallic insert part further includes forming another material accumulation in the transition region on an opposite side of the plastic mass from the material accumulation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] There it shows, in each case schematically,

[0021] FIG. 1 shows a sectional representation through a hybrid component according to the invention produced in accordance with a method according to the invention,

[0022] FIG. 2 shows a sectional representation through an internal combustion engine in the region of a cylinder head cover formed as hybrid component according to the invention in accordance with the method according to the invention.

DETAILED DESCRIPTION

[0023] According to FIGS. 1 and 2, a hybrid component 1 according to the invention is shown, which according to FIG. 2 is formed as cylinder head cover 2. The hybrid component 1 according to the invention has at least one coated or uncoated insert part 3 made of metal, which according to FIG. 2 is formed as guide 4 for a pump tappet 5. The pump tappet 5 is moved during the operation of an internal combustion engine 10 equipped with the cylinder head cover 2 according to the invention by way of a rotating cam 11. The cam 11 is non-rotatably connected to a shaft 12, for example a camshaft.

[0024] The hybrid component 1 according to the invention, respectively the cylinder head cover 2, is produced as follows:

[0025] Initially, the insert part 3, according to FIG. 2 the guide 4, is pre-treated, for example roughened on a surface 6 to be over-moulded or back-injected prior to the over-moulding or back-injecting. Following this, the insert part 3, respectively the guide 4, is placed into the injection mould in such a manner that it protrudes on at least one side from a plastic mass 7 to be produced or injected during the injection moulding process. At a transition region 8 from the insert part 3 or the guide 4 to the plastic mass 7, a material accumulation 9 is now provided, which enlarges the surface 6 to be over-moulded or back-injected, i.e. a contact area with the plastic mass 7. By way of this, a tightness and also a strength of the connection can be increased in particular.

[0026] The insert part 3 or the guide 4 is cleaned and/or degreased on the surface 6 to be over-moulded or back-injected prior to the over-moulding or back-injecting. This can take place for example by means of a plasma treatment or a chemical treatment. For example a casting, a ceramic part, an aluminium part, a sintered part or a sheet metal part can be used as metallic insert part 3. In particular, the metallic insert part 3 can be formed solid (see FIG. 1) or as a hollow part (see FIG. 2). Usually, a thermosetting plastic is used as plastic mass 7 for the plastic injection moulding process.

[0027] The metallic insert part 3 can comprise cut-outs 13 on the surface to be over-moulded or back-injected and/or during the further course, wherein via the cut-outs 13 further attachment parts can be connected to the insert part 3. When the cut-outs 13 are provided or arranged in the region of the surface 6 to be over-moulded or back-injected, the plastic mass 7 can pass through the respective cut-out 13 during the injection moulding process and create a particularly stable connection.

[0028] Prior to the over-moulding or back-injecting in the injection mould, the surface 6 to be over-moulded or back-injected is roughened for example in order to thereby enlarge the surface 6 as a whole and achieve higher adhesion forces and a better sealing.

[0029] The cleaning of the surface 6 to be over-moulded or back-injected can be achieved for example by a grinding, polishing, blasting, plasma treating or pickling or chrome-plating. A chrome-plating offers the advantage to generate an increased roughness at the same time, as a result of which the mechanical interlocking is improved. A chrome-plating additionally increases the hardness and durability, prevents corrosion, creates an aesthetic appearance, facilitates cleaning operations on these parts and can additionally be applied to different plastic products which pursue a smooth/shining surface. Particularly a plasma-treating and a coating taking place in the same machine, for example by means of a DLC coat, without any contact with the atmosphere in the meantime, can reduce the risk of an oxidising of the surface, in particular in the case of aluminium insert parts, while on the surface 6 to be over-moulded or back-injected honeycomb-like recesses (not shown) with a depth T between 0.1 and 0.3 mm can also be provided, which bring about a better interlocking with the plastic mass 7. The insert part 3, respectively the guide 4, protrudes from the plastic mass 7 at an angle α between 60° and 90°.

[0030] By way of the method according to the invention with the material accumulations 9 provided according to the invention, the contact area between the metallic insert part 3, respectively the guide 4 (see FIG. 2) and the plastic mass 7 of the hybrid component 1, respectively the cylinder head cover 2, can be enlarged and thereby the tightness increased. A firmer anchorage of the metallic insert part 3 in the plastic mass 7 can also be achieved. Here, the plastic mass 7 and the material accumulation 8 are formed in one piece, provided that the material accumulation 9 is produced simultaneously with the plastic mass 7 during the injection moulding process. Purely theoretically it is also conceivable that initially the metallic insert part 3 is over-moulded or back-injected with the plastic mass 7 on the surfaces 6 to be over-moulded or back-injected and subsequently, in a further injection moulding operation, the material accumulations 9 are moulded on. Preferentially, this takes place however in a common operating step.

[0031] Particularly in the case of a cylinder head cover 2, as is shown according to FIG. 2, it is possible to firmly and tightly connect a metallic insert part 3 provided as guide 4 for a pump tappet 5 with the plastic mass 7 by way of the material accumulations 9 in the transition region 8. The plastic mass 7 is an integral part with the material accumulations 9, i.e. produced from one casting. To date, a guide of the pump tappets 5 has only been possible in metallic cylinder head covers since the sealing effect or strength of the anchorage required for this purpose was not possible with cylinder head covers injection moulded from plastic. The sealing between connected metal part and plastic cover is important for environmental protection reasons and for reducing the fire hazard, since leaking oil can ignite on a hot component, for example on an exhaust manifold. The particular challenge of a mounting for an injection pump are the high forces that have to be transmitted and the higher risk of leakage as a consequence of a connection weakness connected with this. In addition, an oil-contaminated engine compartment results from an oil leakage which can be attributable to the manufacturer of the cylinder head cover.

[0032] Here, the material accumulations 9 can be provided on both sides, as a result of which a significant enlargement of the surface 6 to be over-moulded or back-injected and thus of the surface 6 serving as contact area for the plastic mass 7 or the material accumulations 9 of the plastic mass 7 can be created.