EP1754946B1 - Heat exchanger - Google Patents

Description

The present invention relates to a heat exchanger, and more particularly to a heat exchanger for an automotive air conditioning system.

In a parallel-current capacitor, poor compression of the capacitor components leads to various cosmetic defects during soldering of the capacitor components. These errors can lead to rejects or additional processing and rework, and can even lead to customer dissatisfaction and rejection of the product. Poor compression can result due to the natural deviation of the fin and tube height, which can be very difficult to control. In addition, thermal expansion in a brazing oven can cause press joints to expand and lose their effectiveness.

1. (1) Herausfallen von Lamellen - eine unvollständige Verpressung wird die Lamelle nicht ausreichend halten, um die Schwerkraft zu überwinden, wenn der Kondensator hergestellt wird, was bewirkt, dass die Lamelle aus ihrer Position fällt. Ein Herausfallen der Lamelle tritt auf, wenn die Lamelle aus ihrer Position zwischen zwei Rohren herausfällt.
2. (2) Aufstellen von Lamellen - eine unvollständige Verpressung wird die Lamelle nicht ausreichend halten, um die Kraft von Gebläsen, die nach oben blasen, um überschüssiges Flussmittel während der Verarbeitung zu entfernen, und/oder Ofengrenzen ("Vorhänge") zu überwinden, welche entlang der oberen Fläche des Kondensators entlang ziehen, wenn er von einer Ofenzone zu der nächsten passiert. Die Lamelle wird als ein Ergebnis nach oben gehoben. Der kosmetische Effekt dieses Fehlers ähnelt dem Herausfallen von Lamellen, aber die Lamelle befindet sich in entgegengesetzter Richtung außerhalb ihrer Position.
3. (3) Lamellenfenster - eine unvollständige Verpressung wird die Lamelle nicht ausreichend an Ort und Stelle halten, so dass der Spalt zwischen dem Sammelrohr und der Lamelle unverändert ist, wenn er durch den Ofen passiert. Lamellenfenster können auftreten, wenn das Lamellenende von Vorhängen im Ofen ergriffen und zurückgedrückt wird. Wenn das Lamellenfenster an der Ecke des Kerns auftritt, erfolgt dies üblicherweise aufgrund dieser Ursache.

Errors caused by incomplete compression include:

1. (1) lamella falling out - incomplete grouting will not keep the lamella sufficient to overcome gravity when the capacitor is made, causing the blade to fall out of position. Falling out of the lamella occurs when the lamella falls out of its position between two tubes.
2. (2) Setting up slats - incomplete compression will not sufficiently hold the slat to overcome the force of blowers blowing upwards to remove excess flux during processing and / or furnace boundaries ("curtains") along the top surface of the condenser as it passes from one furnace zone to the next. The slat is lifted up as a result. The cosmetic effect of this error is similar to lamella falling out, but the lamella is out of position in the opposite direction.
3. (3) Louvre windows - incomplete grouting will not sufficiently hold the fin in place so that the gap between the manifold and the fin is unchanged as it passes through the furnace. Louvre windows can occur when the lamella end is gripped and pushed back by curtains in the oven. When the louver window occurs at the corner of the core, it is usually due to this cause.

In addition to the above three errors, a kernel shift is another error that can occur. During the core cover displacement, the outer core cover shifts during installation of the solder frames, causing an undesirable cosmetic defect, although the performance of the capacitor is not affected. This typically occurs when the cover is hung on the crimping frame which holds the capacitor during the soldering process. Products with this error can not be reworked and can only be sorted out. A kernel shift shift occurs when the Cover slides along the slat along. It should be noted that the cover is not centered to the manifold and the blade below releases.

Dropping lamellae and setting up louvers are typical failure modes for certain types of capacitors. Incomplete compression can occur during the operation of the core structure, as previously mentioned, due to natural deviations of the lamellar and tube height. Where the core construction process can be controlled to minimum values, incomplete grouting may still result as a natural thermal expansion effect in the furnace.

To combat the effects of thermal expansion in the furnace (which can not be avoided), the core can be protected by placing a bar or rail under and along the blades that are typically affected. This rail serves as a preventive barrier that prevents slats from falling out, even if otherwise a loss of compression would cause the slat to fall out. However, this rail is ineffective against setting up the slats.

However, there are several disadvantages to the rail located under the corner fins, in particular: (a) if the core is not completely seated, the rail is ineffective; (b) if the rail is bent or deformed, it may damage the blade that should protect it; and (c) if the rail has not been properly treated, the slat that supports it may be soldered to the rail, causing the slat to be damaged.

To combat the effects of the curtains pulling the slat up or back to cause the slat or louver windows to be erected, a protective "cage" may be placed on top of the capacitor prior to soldering. This cage, which is essentially a Stainless steel wire mesh is fabricated to attach to the compression frame above the condenser without touching the condenser, protects the core from the furnace curtains, but allows sufficient airflow to allow good soldering, and is also light enough, so that it does not become a heat sink. However, this system will not prevent the blade from being set up by the flux fan.

Unfortunately, the cage has a fundamental disadvantage in that it adds an expense to the method in the form of a non-value enhancing manner. It is also subject to damage which makes it difficult to place it and creates a risk of destroying the furnace.

In order to prevent a core cover displacement, the effect of the covers hung on the press frame should be prevented. Keeping the frame clean and maintained helps, but is not a perfect solution to this effect. Additionally, although workers may be encouraged to inspect a product immediately after the frame has been installed and before the condenser is initiated into the process, if it is determined that a capacitor is incompletely inserted into the frame, a mallet may be used to put him in the right position; however, this approach is undesirable.

The major disadvantage in controlling core construction and blade fabrication to ensure uniform crimping and tube and fin height is that it is difficult or impossible to do so in a "preventative" manner. Typically, problems are discovered after the occurrence; even if the affected capacitors can be found, there is a high probability that they have already started the soldering process, after which they can not be recovered. Unfortunately, even a 100% verification of the capacitor is only minimally effective.

Keeping the frames clean to prevent a core cover displacement is a labor-intensive process and difficult to control since there is no assurance that all the frames will be cleaned at the proper intervals. In addition, the frame purity is limited in its effectiveness in preventing core depression. The practice of using a mallet to position a condenser is undesirable for reasons that are readily apparent from the observation of the method.

A device for holding the end elements in place is shown in FIG DE 198 14 827 A1 beschirieben- This device comprises a side plate which is fixed to the manifold by means of elements. However, this configuration does not allow condensate or other fluid to flow between the side plates and the manifold. Therefore, the condensate that forms on the side plate may accumulate and lead to corrosion of the heat exchanger.

Another device for holding the end elements in place is in the U.S. Patent 5,894,885 described. This device includes tailpipes fixed to collectors. This design involves additional costs and does not allow the condensate or other fluid to flow between the collectors and the tailpipes. Therefore, condensate that forms at the junction between the collectors and the tailpipes may accumulate and lead to corrosion of the heat exchanger.

JP2003004395 shows a heat exchanger with a holding device for an end member (140) with all features of the preamble of the independent claim.

Summary of the invention

Consequently, it is an object of the present invention to remove a fluid, for example a condensate, between end element (140) and collecting tube (10, 150). Another advantageous effect is the effects of natural deviation of lamellar and tube height and the thermal To overcome or compensate expansion of the furnace, while the outer Kemabdeckungen, which serve as protection for the outer fins held.

According to the invention, a collector for a heat exchanger comprises a collection tube, wherein the collection tube has a plurality of openings for tubes, and wherein each end of the collection tube has a plurality of projections for holding an end member.

Furthermore, the heat exchanger has a first header, a second header substantially aligned parallel to the first header, a plurality of tubes extending between the first and second header, and at least one end member adjacent to the plurality of tubes is disposed and extends between an end of the first manifold and an end of the second manifold, wherein each end of the manifold having a plurality of projections for holding the end member.

Heat exchangers according to the invention are used in motor vehicle heating and air conditioning systems. Such devices potentially include apparatus for providing hot fluid and cold fluid and a heat exchanger having a first header, a second header substantially aligned parallel to the first header, a plurality of tubes extending between the first and second header tubes second header, and an end member disposed adjacent to the plurality of tubes and extending between an end of the first header and an end of the second header, each end of the header having a plurality of protrusions for holding the end member.

Thus, a motor vehicle may include an automotive heating and air conditioning system having a heat exchanger having a first header, a second header substantially aligned parallel to the first header, a plurality of tubes extending between the first and second header, and at least one end member disposed adjacent to the plurality of tubes and extending between an end of the first header and an end of the second header, each end of the header having a plurality of protrusions for holding the end member.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments when taken in conjunction with the accompanying drawings.

Brief description of the drawings

• Figur 1 eine typische Anordnung eines Rahmens und eines Kondensators vor dem Löten zeigt.
• Figur 2A und Figur 2B eine typische Eckverbindung vor bzw. nach dem Löten zeigt.
• Figur 3 eine Seitenansicht einer Darstellung einer äußeren Rohrhalterung gemäß einem Ausführungsbeispiel der vorliegenden Erfindung ist
• Figur 4 eine Draufsicht auf ein Sammelrohr gemäß einem Ausführungsbeispiel der vorliegenden Erfindung ist.
• Figur 5 eine vergrößerte Ansicht des Bereichs B von Figur 4 ist, welche die Sammelrohröffnungen für Wärmetauscherrohre gemäß einem Ausführungsbeispiel der vorliegenden Erfindung zeigt.
• Figur 6 eine vergrößerte Ansicht des Bereichs C von Figur 4 ist, die ein Ende eines Sammelrohres gemäß einem Ausführungsbeispiel der vorliegenden Erfindung zeigt.
• Figur 7A eine vergrößerte Ansicht des Bereichs D von Figur 6 ist, die einen Vorsprung zum Halten eines Endelements gemäß einem Ausführungsbeispiel der vorliegenden Erfindung zeigt.
• Figur 7B eine beispielhafte, alternative Struktur bezüglich der Struktur, die in Figur 7A dargestellt ist, gemäß einem anderen Ausführungsbeispiel der vorliegenden Erfindung ist.
• Figur 7C eine beispielhafte, alternative Struktur bezüglich der Struktur, die in Figur 7A dargestellt ist, gemäß einem anderen Ausführungsbeispiel der vorliegenden Erfindung ist.
• Figur 7D eine beispielhafte, alternative Struktur bezüglich der Struktur, die in Figur 7A dargestellt ist, gemäß einem anderen Ausführungsbeispiel der vorliegenden Erfindung ist.
• Figur 8 eine Ansicht eines Endes eines Sammelrohres gemäß einem Ausführungsbeispiel der vorliegenden Erfindung ist.

An exemplary embodiment of the invention will be described in detail in the following and is illustrated in the drawings, in which:

• FIG. 1 shows a typical arrangement of a frame and a capacitor before soldering.
• FIG. 2A and FIG. 2B shows a typical corner joint before or after soldering.
• FIG. 3 a side view of a representation of an outer pipe support according to an embodiment of the present invention
• FIG. 4 a plan view of a manifold according to an embodiment of the present invention is.
• FIG. 5 an enlarged view of the area B of FIG. 4 which shows the manifold holes for heat exchanger tubes according to an embodiment of the present invention.
• FIG. 6 an enlarged view of the area C of FIG. 4 which is an end of a manifold according to an embodiment of the present invention.
• FIG. 7A an enlarged view of the area D of FIG. 6 which shows a projection for holding an end member according to an embodiment of the present invention.
• FIG. 7B an exemplary, alternative structure with respect to the structure, which in FIG. 7A is shown, according to another embodiment of the present invention.
• FIG. 7C an exemplary, alternative structure with respect to the structure, which in FIG. 7A is shown, according to another embodiment of the present invention.
• Figure 7D an exemplary, alternative structure with respect to the structure, which in FIG. 7A is shown, according to another embodiment of the present invention.
• FIG. 8 a view of one end of a manifold according to an embodiment of the present invention is.

Detailed Description of the Preferred Embodiments

In order to avoid the drawbacks discussed above, the outer core covers are held in such a way that shifting is impossible and that compression losses are minimized. In existing designs, there was no support for the outer sipe and core cover during manufacture, except by the one created by the squeeze frame.

In this regard shows FIG. 1 a typical arrangement of a frame 300 and capacitor 200 before soldering. The condenser 200 includes a manifold 230 at each end and a tube-fin matrix 240 between each manifold 230. The tube-fin matrix 240 includes heat exchanger tubes 250 and regions 260 between the tubes 250 for fins (not shown). The crimping points 210 are shown only for the purpose of effect. Typically there is compression along the length of the covers, but compression can also terminate about 50mm from the headers.

FIG. 2 shows a more detailed view of a corner joint 220 of the frame 300 and capacitor 200 of FIG. 1 , When the capacitor 200 and the frame 300 are placed in a brazing furnace, the frame members heat up and undergo thermal expansion. The direction of thermal expansion is in FIG. 1 indicated by the arrow X. The thermal expansion is a function of the material, the temperature change and the length of the expanding material. Long components are most affected by thermal expansion. In the case of the components of FIGS. 1 and 2 the core cover is farthest from the center of the manifold. Further, when the capacitor collecting pipe 230 is made of aluminum, and the frame 300 is made of stainless steel, the thermal expansion of the aluminum capacitor collecting pipes is 230 larger than that of the stainless steel frame 300. Thus, as the manifold 230 expands in the furnace, the outer core cover 270 is bent against the solder frame 300. Although the first active tube 255 is detected by the manifold 230 and is slightly closer to the center of the manifold. The outer core cover 270 is slid away from the end of the manifold 230 without support. Further, the resulting gap between the outermost active tube 255 and the core cover 270 is made larger than the height of the sipe (not shown), and the sipe loses its compression.

FIG. 3 FIG. 10 is a side view of a reproduction of the outer pipe support according to a preferred embodiment of the present invention. FIG. In the example of FIG. 3 For example, a condenser assembly 100 includes a manifold 10, heat exchanger tubes 120 forming louvered regions 130 (not shown), and an outer core cover or element 140. The capacitor assembly 100 is compressed by a soldering frame 300. In accordance with a preferred embodiment of the present invention, the manifold 10 has protrusions 30 to hold the outer core cover or member 140 in place during manufacture, including brazing. Therefore, since the outer core cover or member 140 is held in place, the first active tube 125 is also held in place and the manufacturing disadvantages previously described are minimized.

FIG. 4 shows a plan view of a manifold 10 according to a preferred embodiment of the present invention. The collecting tube 10 has openings 20 for heat exchange tubes, which are arranged along the longitudinal axis A of the collecting tube 10. The manifold 10 also has "fingers" or protrusions 30 at each end 40 of the manifold to hold the members 140 at the ends of the manifold. The elements 140 held by the projections may be end plates, unused Be pipes or other end elements, which are known from the heat exchanger theory. The projections 30 may be integral with the body of the manifold 10.

FIG. 5 shows a detailed view of the area B of FIG. 4 showing the openings for the heat exchanger tubes according to an embodiment of the present invention. As in the example of FIG. 5 As shown, the openings 20 for the heat exchanger tubes may be curved so that the openings 20 follow the curvature of the heat exchanger tubes 120. This configuration assists in connecting the manifold 10 and the heat exchange tubes 120 during soldering, and further assists in sealing the manifold 10 to the heat exchange tubes 120.

FIG. 6 shows a detailed view of a manifold end 40 according to an embodiment of the present invention. The collection tube end 40 has "fingers" or protrusions 30 to hold elements to the collection tube. The "fingers" or protrusions 30 form portions 35 for holding members 140. These portions 35 can be made smaller in size than the openings 20 for the heat exchanger tubes 120 so that the members 140 are held firmly in place during manufacture of the condenser become. Further, the header ends 40 may include a portion 50 that allows fluid, such as condensate, to flow between the members 140 and the header 10. In the example of FIG. 6 The region 50 is a planar region that provides a gap between the element 140 and the manifold 10. The region 50 may also be a groove in the manifold 10 or other configuration that provides a gap between the member 140 and the manifold 10.

By providing a region or gap between the element and the manifold, it becomes a fluid, such as condensate, for example. which collects on the manifold and the element allows to flow instead of collecting at the junction of the manifold and the element. This prevents or delays corrosion in the manifold. While the region 50 has been exemplified, present herein as a planar region, the region 50 may also be formed by one or more planar or curved surfaces or a combination of planar or curved surfaces intended to provide the surface or surfaces provide sufficient gap to allow a fluid to flow between the manifold and the element.

FIGS. 7A . 7B, 7C and 7D 12 show detailed views of exemplary "fingers" or protrusions 30 for holding an element at the end of a manifold 10 in accordance with further preferred embodiments of the present invention. In these other preferred embodiments, the "finger" or protrusion 30 creates a grip portion 39 for holding the member 140 in the manifold. In the exemplary embodiments shown in FIG FIG. 7A . Figure 7B, Figure 7C and Figure 7D have been provided, one or more surfaces 37 have been provided, which form a gap between an element 140 (not shown here for reasons of clarity) and the manifold 10 (not shown here in its entirety for reasons of clarity). As an example, while the surface 37 has been illustrated herein as a planar surface, the surface may also be formed by one or more planar or curved surfaces or a combination of planar and curved surfaces provided so that the surface or surfaces provide sufficient clearance to allow fluid to flow between the manifold and the element. Also, one or more areas 37 may be provided in addition to or instead of the area 50 discussed above.

FIG. 8 shows an end view of a manifold 10 according to another preferred embodiment of the present invention. In the example of FIG. 8 the collecting tube 10 has projections 30 for holding an element 140. The protrusions 30 form a slot or slots into which the element 140 is fitted so that the element 140 is held in place during fabrication. The manifold 10 also has openings for receiving heat exchanger tubes. In the example of FIG. 8 the first active tube 125 is shown in place in the manifold 10.

In the example of FIG. 8 the collection tube 10 is shown as a one-piece tube. However, the manifold 10 may also be formed of two or more pieces forming the manifold 10.

Due to the retention of the outer tube using "fingers" 30 that are integrated into the collection tube 10, the outer core cover or element 140 will not be pushed away by the collection tube 10 during expansion. Thus, the dominant factor in determining the separating distance due to thermal expansion is no longer the length of the collection tube 10, but rather the distance between the tubes 120. As a result, the effective separation distance that affects the outer fin is substantially reduced , and the lamella never loses its compression during the Lötkreislaufs. FIG. 3 shows a representation of this effective distance 160.

Advantages of the invention include its proven ability to eliminate the two major failure modes currently observed during capacitor fabrication: tube displacement and lamella falling out. It has also been demonstrated that lamellar windows and erection of lamellae due to the change decrease substantially. These improvements are realized by means of a minimal increase in tool and unit costs.

Another advantage is that this change can be easily integrated into existing tools without noticeably increasing the initial board. Another advantage is that the present invention allows condensate to collect at the end of the header to drain between the header and the retained member. As a result, premature corrosion of the capacitor can be avoided.

The foregoing description of preferred embodiments of the invention has been presented for purposes of illustration and description only. It is not intended to be exhaustive or to limit the invention to the particular form disclosed, and modifications and variations are possible and / or would be obvious in light of the above teachings, or may be acquired from practice of the invention. The embodiments have been chosen and described to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as contemplated for specific use. It is intended that the scope of the invention be determined by the claims appended hereto, and that the claims include all embodiments of the invention, including the disclosed embodiments and their equivalents.

Claims (6)

1. A heat exchanger having a tube-fin matrix having a manifold at each end of the tube-fin matrix, wherein each manifold (10) includes a plurality of apertures (20) for tubes (120, 125; 250, 255); wherein at least one end of the manifold (10) includes a plurality of projections (30) for retaining an end member, wherein the plurality of projections (30) at each end of the manifold (10) form an opening in the end of the manifold (10) and wherein at least one end of the manifold (10) includes at least one portion (50) that, in cooperation with the end member, allows a fluid to flow between the manifold (10) and the end member, characterized in that the portion (50) is arranged on the side of the end member (140) which is opposite the projections (30).
2. The heat exchanger according to claim 1, wherein the projections (30) form at least one semicircular opening at each end of the manifold (10).
3. The heat exchanger according to claim 1 or 2, wherein the at least one portion comprises a flat portion (50) that does not follow the curvature of the end member, or wherein the at least one portion comprises a plurality of flat portions (50) that do not follow the curvature of the end member.
4. The collector according to claim 1, 2 or 3, wherein the at least one portion comprises a curved surface.
5. The collector according to claim 1, 2 or 3, wherein the at least one portion comprises a combination of curved and flat surfaces (37).
6. The collector according to claim 1, 2 or 3, wherein the at least one portion comprises a notch in an opening in the end of the manifold (10).

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