WO1998050751A1 - Device for protecting the radiator of a motor vehicle against projected particles - Google Patents

Abstract

A device is disclosed for protecting the radiator (1) of a motor vehicle against projected particles. The radiator (1) has spaced apart ribbed pipes (2 to 6) for conveying the cooling medium. According to the invention, the ribbed pipe walls, which in the assembled state of the radiator (1) are oriented in the direction of projected particles (arrow 19) and mechanically stressed, are only protected against particle blows by a plating which directly covers them and is mechanically joined thereto without any gap. This plating is preferably a mere material thickening (18) of the ribbed pipes, a bead (21) of elastic material applied on the ribbed pipes and/or a covering strip (23) clipped on the ribbed pipes, several covering strips (23) being appropriately designed as a grid (22).

Description

 Protection device against impinging particles for a radiator in a motor vehicle

The invention relates to a protective device against impinging particles for a radiator in a motor vehicle according to the preamble of claim 1.

Radiators in motor vehicles generally consist of a plurality of cooling tubes, which are arranged in parallel at intervals as web tubes and which are connected to one another by selected heat dissipation plates. Round tubes or flat tubes are used as media-carrying cooling tubes. Such coolers are used, for example, as heat exchangers in the engine cooling circuit or as condensers in an air conditioning system in the vehicle.

In order to obtain an effective cooling performance, such coolers are usually arranged in the front area of the vehicle at a location that can be easily flowed through by the wind. Such a cooling air flow can particles such. B. small gravel, with it, especially when overtaking, oncoming traffic and convoys on roads with insufficiently paved ground. To reduce the weight of the cooler and for a good heat exchange between the cooling air and the cooling medium, the cooling tube walls are dimensioned as thin as possible, so that the coolant-carrying web tubes can be mechanically damaged by such particles. Less critical damage to the surface coating can occur, but the thin-walled standpipes can also be leaked. This leads to a failure of the engine cooling system and the vehicle stopping in connection with costly repairs.

A number of proposals have already been made to reduce these well-known problems: Known generic protective devices for a motor vehicle radiator against impinging particles consist of differently designed protective grids which are arranged at a distance from a radiator. In addition to known, simple protective grilles as a grille, special protective grille designs are known. For example, a fine-mesh, flat wire mesh in an interchangeable frame in front of a vehicle cooler is known (DE 36 29 880 A1), with which contaminants in particular are to be kept away from the radiator fins. A fine-mesh wire mesh, however, clogs itself up with impurities and then disadvantageously hinders the air throughput through the cooler and considerably reduces the cooling capacity.

In a further known protective grille arrangement in front of a cooler (DE 39 16 920 A1), two protective grids with staggered mesh arrangements are attached in front of the cooler at a mutual distance, whereby a larger mesh diameter and thus an improved radiator flow should be possible with the same protective effect. However, such an arrangement with two protective grids held separately is complex and cost-intensive.

Another known protective device for radiators (DE-GB 93 12491), in particular for insects, consists of a grid-like arrangement of vertical, parallel metal strips which are attached at an angle of 45 ° with respect to the longitudinal direction of the vehicle. This means that impinging particles should no longer hit the radiator block directly, but should be deflected according to the angle of attack of the metal strips. However, the cooling air flow is deflected and reduced accordingly. This arrangement is therefore also complex and leads to a reduction in the cooling capacity.

In another known embodiment of a radiator grille at a distance in front of a radiator, a spiral wound from a flat metal strip is used (DE-OS 1 755 802). In addition, an embodiment of a radiator grille from a flexible band is known (DE 44 25 196 A1), which can be wound up and unwound automatically and cleaned in the process. This represents a very complex design, which is particularly ineligible for passenger cars for reasons of cost.

All of the above-mentioned radiator grilles have the common disadvantage that they are intended to protect the radiator surface, which is at risk from a particle impact, overall and globally. This requires a small mesh size for good protection, however, which leads to an unfavorable reduction in the cooling air flow. In addition, protective grids arranged separately at a distance from a radiator are complex to manufacture, require space and weight due to their required stability and brackets.

Protective grids are also known at air inlet openings of housings and encapsulations, in particular engine compartment encapsulations (DE 37 03 716 A1; DE 40 15 304 A1), the cross-sections of which contain cross-sectional profile shapes with undercuts and / or combinations of different materials in order to allow particles and Reduce foreign bodies. A spatial assignment to a vehicle radiator is not available here.

The object of the invention is to provide a protective device against impinging particles for a radiator in a motor vehicle, which does not or only slightly influences the cooling air flow with a good protective function and is simple and inexpensive to produce in a space-saving and weight-saving arrangement.

This object is achieved with the features of claim 1.

According to claim 1, in the installed state of the cooler directed in the direction of impinging particles and thus mechanically stressed web tube walls only armor covering this and connected with them without spacing as particle impact protection.

With the radiator protection device according to the invention, the previous principle of global protection of the entire radiator surface loaded by impinging particles is abandoned. This is based on the knowledge that the areas between the web tubes in any case represent throughflow openings and the end edges of heat dissipation plates oriented in the direction of flow, which point here in the direction of flow, are relatively insensitive to impinging particles. In addition, even more severe damage in the intermediate areas of web tubes cannot lead to a malfunction of the cooler, since cooling medium only flows in the web tubes. The web tubes, which are sensitive to damage, are provided with armor directly and without spacing directly in vulnerable areas, which ensures mechanical protection against impinging particles. Because this armor directly touches the endangered tube walls is assigned and for a good protective function only has to have the same or only a slightly larger width than the endangered web tube areas, the cooling air throughput is advantageously not or only slightly reduced by the protective device. Such a protective device is simple and inexpensive to manufacture and can be installed in a small space. In particular, such armor is to be attached directly to the bridge tube walls and therefore does not require any additional, separate, separate brackets from the cooler.

In a particularly simple to produce embodiment according to claim 2 it is proposed that the armor consists of a thickening of the material of the endangered tube walls compared to other tube walls. Previous manufacturing processes for web tubes, in particular continuous casting processes, can continue to be used, as can previous assembly processes. Due to the material thickening that is only used in a targeted manner at the endangered tube wall areas, the weight of the cooler is increased only slightly and is less than the weight of an arrangement consisting of a weight-optimized, thin-walled cooler with a separate protective grille device. The thickening of the material provides effective protection against denting and leakage due to impacting particles and also increases the stability of the standpipes and thus the entire cooler.

An alternative embodiment of armor, which can optionally be used in addition to the material thickening described above, consists of a caterpillar of elastic material applied to the web tube walls which are at risk of particle flight. This application is advantageously carried out automatically in the manufacture of the web tubes. Silicone, polyurethane or other similar materials can be used as the elastic material. An applied caterpillar can also protrude somewhat over an area at risk of impact, so that this area is not only covered but somewhat overlapped for very secure particle impact protection. With this measure, the cooler flow is influenced only slightly.

A thickening of material on only one side of a web tube may be difficult to recognize when installing a cooler. In order to avoid incorrect assembly of the web tubes with the material-thickened wall side to the direction away from the particle, it may be expedient, particularly in the case of flat tubes, to have both opposite narrow sides with material thickening. to be provided as armor. This prevents confusion between the side tubes.

In a further, alternative embodiment, the armor consists of covering tube rails arranged on and covered by the particle tube walls which are loaded and endangered by particle flight. These cover rails are expediently connected to form a lattice part, the cover rails being arranged in the lattice network at a distance from the web tube walls to be covered. The cover rails or the grid part can be clipped directly onto the web tubes or clipped into the spaces between them. The required clips can be molded directly onto the cover rails or the grid part or can be designed as separate clip pieces. The cover rails, or the lattice part and the clips can be made from sheet metal or preferably from plastic as plastic injection molded parts.

Similar to the above-described applied beads made of elastic material, the cover rails used here can also have a somewhat larger width than the web tube wall areas to be covered. Since the tube wall areas to be covered have only a small expansion, in particular in the case of flat tubes, in comparison to the entire cooler surface, an increase in the width of the cover rails by 20% to 30% compared to the width of the vulnerable tube walls only has an insignificant influence on the cooling air throughput.

In a specific, particularly preferred embodiment, the web tubes as flat tubes have an elongated, narrow and rectangular cross section, each with two opposite narrow sides and broad sides. In the web tubes, cooling medium-carrying longitudinal chambers are formed by several parallel webs lying between the broad sides. The narrow sides of the web tubes are the areas at risk of impact due to particle flight and are formed by the outer webs that support the armor. The armoring of these lateral outer webs consists, according to the above statements, of a material thickening and / or an applied bead of elastic material and / or of a direct covering by a cover rail or by a corresponding grid part. When using the protective device according to the invention, essentially all installation dimensions, assembly lines and brackets are retained as they are used for corresponding coolers without the protective device according to the invention.

Depending on the special design of a vehicle and the arrangement of a radiator, there may be areas at a radiator front that are more or less at risk from particle impact. The outlay for the protective device according to the invention can advantageously be reduced, if necessary, in that only heavily endangered cooler areas or web tube areas are covered by armor according to the invention.

Exemplary embodiments of the invention are explained in more detail with reference to a drawing.

Show it:

1 is a perspective view of a portion of a cooler with a protective device for a motor vehicle in a first embodiment,

Fig. 2 is a corresponding view of a second embodiment, and

Fig. 3 shows a corresponding view of a third embodiment.

In Fig. 1, a portion of a radiator 1 for a motor vehicle is shown with horizontal, parallel web tubes 2, 3, 4, 5, 6, which are connected by corrugated heat dissipation plates 7, 8, 9, 10.

The web tubes 2 to 6 are designed as flat tubes with an elongated, narrow, rectangular cross section, each with two opposite narrow sides 11, 12 and broad sides 13, 14. In the web tubes 2 to 6, parallel webs 15 run as a connection between the respective broad sides 13, 14, through which longitudinal chambers 16, here six longitudinal chambers 16, for guiding a cooling medium (arrow 20) are formed.

The outer webs 17, 18 which laterally delimit the web tubes 2 to 6 form the narrow sides 11, 12 and, as compared to the other wall areas of the web tubes 2 to 6, have a material thickening as armor. In the assembled operating position of the cooler 1, this is arranged in the front of a motor vehicle such that it is flown and flowed through with a flow of cooling air in the direction of the outer webs 18 and through the corrugation of the heat dissipation plates 7 to 11, as indicated by the arrow 19. The cooling air flow (arrow 19) carries particles, such as small stones, sand, etc. The material thickening as armor on the outer webs 18, which are directed against the particle flight, prevent damage, in particular leakage, of the web tubes 2 to 6. The material thickening and armouring of the outer webs 17 opposite the particle flight prevent the cooler from being twisted during assembly the web tubes 2 to 6, an unarmored outer web is arranged in the direction of particle flight. In addition to their protective function and armor, the material thickenings contribute to an increase in stability of the individual web tubes 2 to 6 and thus of the entire cooler 1.

FIG. 2 shows an alternative embodiment of a cooler 1, which essentially corresponds to the embodiment according to FIG. 1, so that the same parts are given the same reference numerals. Web tubes 2 to 6 are also used here, which are connected by corrugated heat dissipation plates 7 to 10. In the web tubes 2 to 6 15 longitudinal chambers 16 are formed by webs through which coolant flows during operation (arrow 20). The direction of installation of the cooler is indicated in connection with the direction of a particle flight (arrow 20).

In the embodiment of FIG. 2, additional armor is provided, a bead 21 made of elastic material, preferably made of silicone or polyurethane, being applied to the narrow sides 11 which are directed against the particle flight (arrow 20) or the outer webs 18. This application can take place in an automated production step together with the production of the web tubes 2 to 6. Impacting particles (arrow 20) cannot damage the web tubes 2 to 6 and in particular do not leak through this armor.

In a third embodiment according to FIG. 3, a partial area of a cooler 1 corresponding to FIG. 1 is again shown, which is additionally covered with armor by a grid part 22 in relation to a particle flight direction. The grid part 22 consists of horizontal and parallel cover rails 23 which are connected by vertical webs 25 and which, in the assembled state, the narrow sides 11 of the web tubes 2 to 6 or their outer webs 18 cover. The grid part 22 can be fastened to the web tubes 2 to 6 or in the spaces between them with molded clips 24 or possibly with separate clips 26 (alternatively shown in broken lines). The cover rails 23 can also be clipped onto the respective web tubes 2 to 6 individually without a lattice structure. The grid part 22 is produced as a plastic injection-molded part. A grille part 22 attached in this way to the cooler 1 provides effective protection against damage from particle flight and in particular prevents the tube tubes 2 to 6 from leaking. The protective effect can be increased in that the covering width of the cover rails 23 is chosen to be 20% to 30% larger is the width of the associated narrow sides 11 of the web tubes 2 to 6.

If necessary, it may be sufficient to use the armor shown in FIGS. 1 to 3 only on a cooler where there are particularly vulnerable places due to particle flight.

Claims

PATENTANS PRINT 1. Protection device against impacting particles for a cooler (1) in one Motor vehicle, wherein the radiator (1) has spacer tubes (2 to 6) carrying coolant, characterized in that the particles (arrow 20) directed and thereby mechanically loaded bridge tube walls only armor that directly covers them and is connected to them without spacing (18; 21; 23) as particle impact protection. 2. Protection device according to claim 1, characterized in that the armor consists of a material thickening (18) in comparison to other web walls. 3. Protection device according to claim 1 or claim 2, characterized in that the Armor consists of an applied bead (21) made of elastic material, preferably made of silicone or polyurethane. 4. Protection device according to claim 2 or claim 3, characterized in that the opposing particles pointing web tube walls (17) have a corresponding armor. 5. Protection device according to one of claims 1 to 3, characterized in that the Armor consists of cover rails (23) which are arranged on the mechanically loaded web walls and cover them. 6. Protection device according to claim 5, characterized in that the armor consists of a lattice part (22) which is mechanically loaded at intervals Has web tubes arranged and directly assigned cover rails (23). 7. Protection device according to claim 5 or claim 6, characterized in that the The grid part (22) and / or the cover rails (23) are attached to or in the spaces between the web tubes (2 to 6) with molded and / or separate clips (24; 26). 8. Protection device according to one of claims 3 to 7, characterized in that the The width of the armor (21; 23) covering the mechanically loaded web tube walls (18) is 20% to 30% larger than the width of these web tube walls (18). 9. Protection device according to one of claims 1 to 8, characterized in that the web tubes (2 to 6) as flat tubes have an elongated, narrow and rectangular cross section, each with two opposite narrow sides (11, 12) and broad sides (13, 14), that are formed by several parallel webs (15) between the broad sides (13, 14) coolant-guiding longitudinal chambers (16) in each of the web tubes (2 to 6), the narrow sides of the web tubes (2 to 6) by lateral, the outside Armor-bearing outer webs (18) are formed so that the web tubes (2 to 6) have a narrow side in the direction of travel of the motor vehicle opposite the particle flight direction (arrow 19), and that the broad sides (13, 14) of opposing web tubes (2 to 6) corrugated heat dissipation plates (7 to 10) are connected. 10. Protection device according to one of claims 1 to 8, characterized in that an armor (18; 21; 23) is only partially attached to cooler areas particularly at risk from a particle impact.