EP0353404B1 - Oil cooler for combustion engines - Google Patents

Description

The invention relates to an oil cooler for internal combustion engines with a housing chamber through which the oil to be cooled flows and with a finned tube block through which a cooling liquid, in particular water, flows, according to the preamble of patent claim 1.

An oil cooler of this type is known from DE-A-34 40 064. Such oil cooler types have the advantage of a relatively high cooling capacity, but cannot be used everywhere because of the installation space required.

From FR-A-22 83 714 a heat exchanger is known which is provided with hairpin-shaped tubes which open into a common water tank. This design shows no oil cooler. There is also no provision for a fin-tube block through which water flows. Rather, it is a desublimator, the pipes of which are to be alternately flowed through by cold or hot oil. The pipe axes of the pipes provided there are each arranged in a common plane. The pipes are on top of each other and aligned with each other. The space requirement of such a heat exchanger would be far too large for use in an oil cooler for a motor vehicle.

Finally, from US-A-25 96 195 a heat exchanger is also known, which has tubes which are bent in a U-shape from a tube sheet, but which are for an evaporator or a condenser should be provided. The arrangement of the pipe bends provided there, some of which are inclined to one another, requires too much installation space and is therefore not suitable for an oil cooler of the type mentioned at the beginning.

The invention is therefore based on the object of designing an oil cooler of the type mentioned at the outset in such a way that, despite the small space requirement, it has a very high cooling capacity.

To solve this problem, the characterizing features of claim 1 are provided in an oil cooler of the type mentioned.

This configuration results in a very close arrangement of the pipes, so that a large throughput of coolant is made possible in the smallest space. This means that the available tube sheet surface for oil cooling is used intensively. In addition, due to the multiple deflection of the cooling water, intensive use of the cooling medium can be achieved. The cooling capacity is therefore high without special installation requirements having to be met.

Advantageous developments of the invention are characterized in the dependent claims. The features of claims 2 and 3 on the one hand allow the water to be guided in a very simple manner despite the thick tube packing and on the other hand the flow guidance for the oil to be cooled. Finally, the features of claims 5 and 6 ensure a simple design, which is particularly suitable for motor vehicle construction. The features of claim 7 result in addition to a streamlined deflection also a very stable water tank that can safely absorb the forces exerted by the oil pressure on the tube sheet.

Fig. 1

die perspektivische, teilweise aufgebrochene Ansicht eines Ölkühlers gemäß der Neuerung,

Fig. 2

den schematischen Schnitt längs der Ebenen II-II in Fig. 1,

Fig. 3

eine vergrößerte Detaildarstellung der Einzelheit III der Fig. 1 am Rand des Rippen-Rohrblockes,

Fig. 4

eine Abwandlung der Einzelheit III der Fig. 1,

Fig. 5

eine Draufsicht auf die offenen Enden der Rohrgabeln des Rippen-Rohrblockes der Fig. 1 und 2 bei abgenommenem Gehäusedeckel,

Fig. 6

die Ansicht auf die Rohrbögen der Ausführungen der Fig. 2 und

Fig. 7

die Ansicht des Rippenrohrblockes (2) der Fig. 5 und 6 in Richtung des Pfeiles VII der Fig. 6.

In the drawing, the invention is illustrated using an exemplary embodiment and is described below. Show it:

Fig. 1

the perspective, partially broken view of an oil cooler according to the innovation,

Fig. 2

the schematic section along the planes II-II in Fig. 1,

Fig. 3

2 shows an enlarged detailed view of detail III of FIG. 1 at the edge of the finned tube block,

Fig. 4

a modification of the detail III of FIG. 1,

Fig. 5

2 shows a top view of the open ends of the tube forks of the fin tube block of FIGS. 1 and 2 with the housing cover removed,

Fig. 6

the view of the pipe bends of the embodiments of FIGS. 2 and

Fig. 7

the view of the finned tube block (2) of FIGS. 5 and 6 in the direction of arrow VII of FIG. 6th

1 and 2, an oil cooler for motor vehicle engines is shown, which consists of a housing chamber (1) and a finned tube block (2) inserted into this housing chamber (1), which has only one tube plate (24) which is fixed is inserted between a mounting flange (41) of the housing chamber (1) and a mounting flange (40) of the attached water box (13). This type of training ensures that the media used for heat exchange (cooling water and oil) are sealed against the atmosphere. If a seal leaks, water or oil can only escape into the environment. A mixture of water and oil is impossible.

5 to 7, the open ends (12, 12 ') of tube forks (6, 6', 6˝) are held, in particular tightly soldered, in the area their parallel legs (7) are connected to ribs (8) running transversely to their longitudinal direction, each of which is pierced by the legs (7). The pipe forks (6, 6 ', 6˝) and the plurality of fins (8) form in a known manner a soldered finned tube block (2) which is flowed through by the oil to be cooled in the embodiment. This is achieved in that a partition (19) is provided between an inflow (20) in the underside of the housing chamber (1) and a drain (21) also provided on the underside of the housing chamber (1), which in the exemplary embodiment is firmly connected to the finned tube block (2) and lies close to the housing chamber wall. Oil that enters through the opening (20) in the direction of the arrow (25) is therefore deflected in the interior of the housing chamber (1) to the left of the partition (FIG. 2) in the direction of the arrow (26) and flows through the ribbed Pipe block is deflected downwards in the other chamber of the housing chamber (1) in the direction of the arrow (27) and can then, according to the Cooling, emerge from the opening (21) in the direction of the arrow (28). Of course, an inflow and outflow of the oil through the side walls of the housing chamber would also be possible.

The flow path of the water used to cool the oil initially goes in the direction of arrow (29) through the inlet port (22) into a first train (3) of pipe forks (6), the left leg ends of which, see FIGS. 2 and 5, each as Inflow openings serve for the water that flows in the direction of arrow (30) through the legs (7) of the pipe forks (6). This is achieved in that the water tank (13) in the embodiment with the first partition (14) between the open ends (12) and (12 ') of the pipe forks (6) and with further partitions (15) and (16) each again grips between the open ends of pipe forks, each with one leg in one of the chambers in the water tank (13) and with the other leg in the other chamber. The chambers (31, 32, 33) in the water tank (13) are vaulted; the partitions (14, 15, 16) also serve to support the tube sheet (24) against the water tank (13).

5 and 6 that two rows (17) and (18) of pipe forks are assigned to a train (3) or (4) and (5), the individual pipe forks (6, 6 ', 6˝) parallel to each other, but in each case in the different rows (17) and (18) are arranged so offset to each other that the open ends (12) of the first leg of the pipe forks in the row (18) in the middle plane between the open ends (12a, 12a ') of the first row (17) of pipe forks, so that the respectively assigned pipe bends (10, 10'; Fig. 6) offset from one another on the underside of the ribs Pipe block (2) are. The first partition (14) is, as can be seen from Fig. 5, designed so that it zigzags between the first open pipe ends (12 a, 12) and the second open pipe ends (12 a ', 12') two rows (17) and (18) of pipe forks run. The ends (12 ', 12a') open into the second chamber (31) separated from the first chamber in the water tank (13). There is therefore the deflection of the water flowing through in the direction of arrow (34) in the next train (4) and from there because of the arrangement of the partition (15) in the chamber (32) and then, because of the partition (16) in the outlet chamber (33). The cooling water is therefore deflected three times before it can leave the last chamber (33) in the water tank (13) in the direction of arrow (35). This results in an excellent utilization of the cooling capacity of the cooling water used, which can also flow through the oil cooler in sufficient quantity because of the double-flow arrangement. The cooling performance of the new oil cooler is therefore excellent. The space requirement is small.

The vertices (9) of all bends (10, 10 ') of the pipe forks (6, 6', 6˝) are (Fig. 7) in a common plane (11). All pipe forks (6, 6 ', 6˝) have the same dimensions. The production of the finned tube block (2), which is soldered in the usual way, is therefore extremely simple. The installation space is given simple geometric dimensions because of the compact design of the finned tube block (2).

3 and 4, a variant of the edge formation of the finned tube block (2) is shown. It can be seen that each of the ribs (8) can be provided with a raised edge (36) or (37) which, after soldering, results in a tight partition wall, which also contributes to the oil in the direction of the arrows (26 ) into the finned tube block (2) and exits the finned tube block in the direction of the arrows (27). Fig. 4 shows a variant in which in the edge (37) are impressions (38) which together form a rib which, after installation in the housing chamber (1), can contact the associated housing wall and thereby prevent it, that the oil to be cooled approximately between the housing wall of the housing chamber (1) and the from the edges (36) or (37) formed flow wall can flow through.

Claims (8)

1. Oil cooler for internal combustion engines with a housing chamber swept by oil to be cooled, and with a ribbed tube unit (2) swept by a cooling liquid, particularly water, and which consists of at least two sets (3, 4, 5) of tubes and of ribs (8) extending transversely to the tubes, in which arrangement there is associated with the open tube ends a water box (13) with partitions which engage between the open ends of the tubes of a set (3, 4, 5), characterized in that each set (3, 4, 5) consists of two rows (17, 18) of tube bifurcations (6, 6', 6"), the bends (10, 10') of which are situated offset relative to each other in such a manner that in each case a tube branch (7) of a row of tube bifurcations (17, 18) extends in the middle of the branches (7) of the other row of tube bifurcations, that the summits (9) of all bends (10, 10') of the tube bifurcations (6, 6', 6") are situated in a common plane (11), and that a single water box (13) associated with the open tube ends (12, 12') is provided with partitions (14, 15, 16) which extend in zig-zag fashion between the first tube branches (7a) of the second row of tube bifurcations (18) and the second tube branches (7b) of the first row of tube bifurcations (17).
2. Oil cooler according to claim 1, characterized in that three sets (3, 4, 5) with respectively two rows (17, 18) of tube bifurcations are provided.
3. Oil cooler according to either claim 1 or claim 2, characterized in that the sets (3, 4, 5) are mounted transversely to the flow direction of the oil, and in that, engaging between the bends (10, 10') of the tube bifurcations (6, 6') of two sets (3, 4), is a partition (19) which applies closely to the housing chamber (1).
4. Oil cooler according to claim 3, characterized in that the inflow and outflow openings (20, 21) for the oil are mounted on both sides of the partition (19).
5. Oil cooler according to claim 3, characterized in that the partition (19) is mounted rigidly on the ribbed tube unit (2).
6. Oil cooler according to one of claims 1 to 5, characterized in that all tube bifurcations (6, 6', 6") have the same dimensions,
7. Oil cooler according to claim 1, characterized in that the partitions (14, 15, 16) are parts of the walling of chambers (31, 32, 33) constructed vault-like, which are formed in the water box (13) to deflect the cooling liquid.
8. Oil cooler according to one of claims 1 to 7, characterized in that the ribbed tube unit (2) has a tube bottom (24) which is inserted between the sealingly jointly connected securing flanges (40, 41) of the water box (13) and of the housing chamber (1).

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