DE102004051227A1 - Thermoplastic plastic air or coolant heat transfer component for motor vehicle has an oil based coating to resist oxidation - Google Patents

Abstract

An oxidation protection coating covers some or all areas of the component. Coatings are based on a semi- or completely synthetic oil(8) or an oil containing material. The component comprises a ribbed block and has at least one inlet chamber and at least one outlet chamber for a fluid medium. Inlet and/or outlet chambers are made of thermoplastic plastic. Coatings are applied to the inward and/or outward facing surface of the inlet chamber and/or the outlet chamber. Coating application may occur either after molding the component, during the molding stage or by spraying into an open tool so that it covers the plastic during molding. An independent claim is included for a method for applying an oxidation resistant coating of oil(8) or oil containing material, preferably by painting, spraying or dipping, onto a plastic component, in particular the inlet and/or outlet chamber of a heat transfer unit.

Description

The Invention relates to a device, in particular a heat exchanger, in particular a charge air cooler or coolant radiator, in particular for motor vehicles.

Out the Shell Lexicon "Internal combustion engines, Supplement of ATZ and MTZ ", Episode 33, is a charge air cooler known. It consists of a finned tube block, which with a charge air inlet chamber and a charge air outlet chamber is connected. This can be hot charge air from an internal combustion engine of the motor vehicle through flat tubes of the finned tube block. Furthermore leads the hot charge air over between the ribs associated with the flat tubes, which are exposed to ambient air, a large part the heat to the ambient air.

Warmer air has a lower density and thus contains less oxygen, the for the combustion process is necessary. Hot air means less Power. Thus, it is advantageous, the temperature of the charge air to reduce combustion to provide more oxygen. At This position will be frequent a charge air cooler used to a higher Achieve efficiency in combustion. As a result, can achieves a higher engine output with the same or even lower fuel consumption become. Furthermore, it is possible by the use of intercoolers, the Reduce pollutant content in the exhaust gas.

in the Course of the sharper Expectant emissions regulations will also be the thermal requirements to the components of intercoolers constantly increased. So far used materials for the collection chambers, for example polyphenylene sulfide or especially Polyamide can these thermal conditions at correspondingly high internal pressure not always withstand. In particular, occur at high temperatures Oxidations on, which can ultimately lead to the destruction of the cooler. A use of metallic collecting chambers, that could cope with the burdens, or of very high quality specialty plastics, divorces in the Rule for one or more of the following reasons. So are for a production a component in the intended function frequently further mechanical processing steps and elaborate alloys or the like necessary. These are optional also associated with a comparatively strong weight gain, in the automotive field with regard to low fuel consumption just not the desired one Requirement profile corresponds. In addition, economic considerations due to their usually very high costs a role.

adversely on an above-mentioned charge air cooler made of conventional plastic materials is therefore that, in the known configuration, it requires the future required, especially the thermal requirements is not equal.

at Coolant coolers are also used plastic components. Such are, for example, the water tanks of coolant coolers or radiators, casing of thermostats or water pumps or pipes or groups of Pipes. Such plastic components that carry coolant Kings Kings by the coolant age yourself. This process is known as hydrolysis.

Of the Invention is therefore the object of a device with coolant leading or Air leading Components, in particular heat exchangers, such as intercoolers, Coolant cooler or for example, the water boxes of Coolant coolers or radiators, Housing of Thermostats or water pumps or pipes or groups of pipes, of the type mentioned in such a way that these components are economical to manufacture and at the same time the thermal To fit in requirements.

These The object is achieved with the features of claim 1.

The Invention is based on the consideration, that the components concerned for the intended application in an economical and simple way protected before mostly thermally induced oxidation should be. For such a design can also from a stability point of view comparatively inexpensive conventional thermoplastic Plastic materials, which are usually ductile than by themselves made of high temperature resistant special plastics. This usual Materials are easier to process, and those for processing necessary tools are subject to less wear, which also causes the tool life increases and thus costs, for example for repair and replacement, be reduced. The use of metals is often associated with elaborate post-processing steps, such as welding, Turning, milling, grinding and / or polishing, and often with a not insignificant weight increase connected. For these reasons is straight instead of using a metal as the base material the use of a comparatively light material, namely plastic, intended.

For a simple oxidation protection and an upgrade for use in the temperature range of 220 ° C to 260 or 320 ° C provided as the base material plastic, a corresponding coating of the same desired. For effective protection, the coating should be quickly and uniformly applied and have good wetting and adhesion properties on the plastic. For oils are particularly suitable. These can be due to their consistency particularly easy to apply to the surface to be coated of the plastic and penetrate in porous structures of the plastic in the cavities. This ensures reliable shielding from the environment. They prevent the direct contact of atmospheric oxygen with the plastic, which could otherwise lead to undesirable oxidation reactions.

According to the invention, it is provided that an air leader or coolant leader Part, such as the inlet chamber and / or the outlet chamber for a to be cooled Medium, or another coolant leader Part made of a thermoplastic material, at least in some areas with an oxidation protection coating from oil or from an oily one Cloth is provided.

When Base material is a common plastic for the reasons mentioned above, preferably Polyphthalamide (PPA) or polyamide (PA), especially as PA 6 or used as PA 66.

For an improvement The strength properties of the base material is the plastic used expediently strengthened. Therefore, the plastic are preferably reinforcing materials, in particular Glass and / or carbon fibers, added.

Around a depending on the application area specific oil coating for the plastic to ensure, are as oil or in oily Substance advantageously mineral, synthetic or vegetable oils used. So can used in the choice of coating oil oils be anyway, for example, in the automotive field on the to be coated surface would arrive. This can be dispensed with a foreign coating. Furthermore may also be due to wear of various sealing systems or also by so-called blowby vapors in crankshaft venting usually in the intercooler penetrating oil possibly partially used oily Supplement protective layer.

For one The protection against oxidation is especially matched to the field of application from oil or from an oily one Fabric preferably on the inwardly and / or outwardly directed area the inlet chamber and / or the outlet chamber before.

In favor of a particularly effective oxidation protection of the plastic becomes the oil or the oily one Substance expediently especially evenly the one to protect area a plastic component of the device, in particular to the inlet chamber and / or the outlet chamber of a heat exchanger, applied. To is at the same time economic Aspects preferably a common one Surface coating process such as painting, spraying or diving provided. This will be the surface protection also applied particularly environmentally friendly.

Around the intended as a base material plastic reliably before harmful To protect oxidations, The oxidation-inhibiting oil is suitably so early as possible on the to be protected surface applied. For a particularly good and lasting protective effect, the oil is preferably directly after the forming process, in particular after injection molding, applied to the plastic provided as the base material. In particular, polyamides are then due to their porous structure especially for the oil receptive.

According to one Variant becomes the oil during the shaping processing, in particular during the injection molding, applied to the plastic material. Preferably, the oil is in a open injection mold introduced, particularly preferably sprayed, so that the oil or a part of the oil while of injection molding on the surface the plastic material passes. The injected part then has one at least slightly oily surface.

use finds a device described above expediently as a heat exchanger, preferably as intercooler, in order to prevent oxidation of the chamber surface at high temperatures of the charge air. Alternatively, advantageously, the use of the device comes as coolant cooler in Consideration.

The advantages achieved by the invention are in particular that a component can be produced by applying an oxidation protective coating of oil on a conventional plastic in a particularly simple, economical and ecological way, the oxidation from atmospheric oxygen, especially in the temperature range from 220 ° C to 320 ° C is protected. Especially the choice of a low-priced and readily available plastic with comparatively low weight as a base material and its unaufwendige and reliably Coating with a suitable oil, which may already be used in this area or frequently enters this area, predestines the material produced in this way, especially for components in the region of a heat exchanger, in particular a charge air cooler of a motor vehicle. Thus, a heat exchanger, in particular a charge air cooler, from an economic point of view compatible and executed in accordance with thermal requirements.

One embodiment The invention will be explained in more detail below with reference to a drawing. In this demonstrate:

1 a spatial representation of a collection chamber of a charge air cooler, and

2 a sectional view of the collection chamber after 1 ,

Same Parts are provided with the same reference numerals in all figures.

One embodiment The invention will be explained with reference to a charge air cooler. However, according to the invention others, like the above components instead conceivable be.

1 shows a spatial representation of a collection chamber 1 a charge air cooler, not shown. This collection chamber 1 , Which represents a charge air inlet chamber, consists in the embodiment of a plastic material in the form of reinforced with glass fibers polyamide. The charge air chamber serves to hot charge air 2 to lead from an internal combustion engine of a motor vehicle to a finned tube block, not shown, and evenly distributed to the tubes. In a similar or identical embodiment, it could also be designed as a charge air outlet chamber. A finned tube block for heat exchangers is well known and will therefore not be further described here.

The collection chamber 1 has a connection 4 on, which is connected to a supply in the direction of the internal combustion engine, and a tube bottom to-circuit surface 6 which, in direct contact or provided with a seal, communicates with a tube bottom of the finned tube block.

2 shows a sectional view through the collection chamber 1 according to 1 in which it can be seen that the in the embodiment outwardly directed plastic surface of the collecting chamber 1 with a coating of oil 8th is provided. This can vary depending on the plastic and oil used 8th an oxidation-resistant collection chamber 1 , Especially at temperatures of 220 ° C to 300 ° C can be achieved.

For oxidation protection coating of the collection chamber 1 with the oil 8th common surface coating methods can be used. Preferably, the protective coating is carried out by painting, spraying or dipping the surface in question with or in oil 8th ,

1

plenum

2

charge air

4

connection

6

Tube sheet pad

8th

oil

Claims (11)

Device for guiding air or coolant with at least one component made of a thermoplastic material, wherein the component of the thermoplastic material at least partially with an oxidation protection coating of particular semi or fully synthetic oil ( 8th ) or made of an oily substance. Apparatus according to claim 1, in particular intercooler or coolant radiator, for motor vehicles, with a finned tube block and at least one inlet chamber and at least one outlet chamber for a medium in which the inlet chamber and / or the outlet chamber consists of a thermoplastic material and at least partially with an oxidation protective coating of oil ( 8th ) or made of an oily substance. Apparatus according to claim 1 or 2, wherein the plastic material as polyphthalamide (PPA) or polyamide (PA), in particular as PA 6 or as PA 66, is present. Apparatus according to claim 3, wherein the plastic Reinforcing materials, in particular glass and / or carbon fibers are added. Device according to one of the preceding claims, in which as oil ( 8th ) or in the oil-containing substance mineral, synthetic or vegetable oils are used. Device according to one of the preceding claims, wherein the oxidation protection coating of oil ( 8th ) or of an oil-containing substance on the inwardly and / or outwardly directed surface of the inlet chamber and / or the outlet chamber is present. Method of applying an oxidation protection coating of oil ( 8th ) or from an oily substance to a plastic component of a device, in particular according to one of the preceding claims, in particular to the inlet chamber and / or the outlet chamber of a heat exchanger, wherein the protective coating by painting, spraying or dipping. Process according to claim 7, in which the oil ( 8th ) is applied to the plastic material directly after the molding process, especially after injection molding. The method of claim 7, wherein the oil is during the shaping processing, in particular during the injection molding, is applied to the plastic material. The method of claim 9, wherein the oil is in a open injection mold introduced, in particular sprayed will, so the oil or part of the oil while of injection molding on the surface the plastic material passes. Use of a device according to one of the preceding claims 1 to 6 as a heat exchanger, especially as a charge air cooler or as a coolant cooler.