GB2044916A

GB2044916A - A heat exchange device for vehicles

Info

Publication number: GB2044916A
Application number: GB8007831A
Authority: GB
Original assignee: Daimler Benz AG
Current assignee: Daimler Benz AG
Priority date: 1979-03-08
Filing date: 1980-03-07
Publication date: 1980-10-22
Also published as: FR2450944B1; FR2450944A1; IT8048083A0; IT1126969B; GB2044916B; SE8001816L; DE2909047A1; SE439802B; DE2909047C2

Abstract

A heat exchange device for vehicles (in particular an oil cooler arrangement in which the oil is cooled by water drawn from the vehicle engine cooling system) includes a first oil cooling heat exchanger 11, and an auxiliary oil cooling heat exchanger 15 connected in parallel thereto. A portion of the oil supplied at 17 to the exchanger 11 can be diverted via a by-pass passage 16 selectively closeable by means not shown, through a connection 18 into the auxiliary heat exchanger 15. When the by-pass passage 16 is open the flow of oil is divided, substantially equally, between the two heat exchangers 11, 15. The arrangement can include an oil filter 38 and the inlet 41 thereto from the heat exchanger 15 is closed when the by-pass 16 is closed. <IMAGE>

Description

SPECIFICATION A heat exchanger device for vehicles The invention relates to a heat exchanger device for vehicles, including a heatexchangerforheatex- change between oil and water.

In the case of conventional heat exchangers of this type, which are usually known as oil coolers, the entire quantity of oil to be cooled flows through the heat exchanger. Accordingly, there is a relatively high resistance to throughflow. This influences the cooling effect. Should it prove that the cooling effect is not adequate, then the oil cooler must be enlarged at considerable expense, and at the same time considerable space is required. Fitment to the vehicle at a later date is extremely difficult and gives rise to high costs, since the entire available oil cooler then has to be replaced by a new larger or differently designed oil cooler. Naturally, a part of the considerable expense is, above all, the high cost of installation.

The invention is based on the problem of providing a heat exchanger device for vehicles which makes it possible for the oil cooler to be of compact construction and, with minimum complication and according to requirements, to augment and enhance the cooling device and at the same time achieve an increased cooling effect, in fact both in the manufacture of new vehicles and also, for relatively low cost, in the improvement of already used vehicles.

According to the present invention there is provided a heat exchange device for vehicles, including a first heat exchanger for heat exchange between oil and water, the exchanger being provided with an oil feed having oil inlet and outlet connectors for the oil, the device including at least one auxiliary heat exchanger connected in parallel to said first heat exchanger and a by-pass passage branching from the oil feed, the passage through which by-pass passage or the outlet from which, is selectively closeable, so that when closed, only the first heat exchanger is effective or by means of which, a part of oil supplied by the oil feed can be diverted before it passes through the first heat exchanger to pass through said auxiliary heat exchanger which has an inlet feed connector connected to the by-pass passage.

This design makes it possible, with simple means and thus little expenditure, to have selectively single heat exchange operation or multi-heat exchange operation. In the latter case, one or a plurality of heat exchangers are connected in parallel with the existing heat exchanger, in fact in each case with outlet-end connection to the by-pass passage. The heat exchanger including the by-pass passage is at the same time compact and small. The fitment of at least one auxiliary heat exchanger or a plurality of auxiliary heat exchangers is possible in all manner of locations on the vehicle, in fact in the minimum of space. Any available space can be utilised for the purpose. Both series manufacture as well as, in particular, the improvement of existing vehicles by adding one or more auxiliary heat exchangers becomes possible without any problem.Fitment involves the minimum expense of labour and materials. Since by reason of the by-pass passage, for example only about half the quantity of oil fed to the heat exchanger device for cooling passes through the first heat exchanger while the other half is diverted into the by-pass passage, the throughflow resistance in the oil cooler is considerably reduced.

This has a positive effect on the cooling performance.

An embodiment of the invention will now be described by way of example hereinafter with reference to the accompanying drawings, in which: Figure lisa diagrammatic side view of a part of an oil cooling device for vehicles; Figure 2 is a diagrammatic front view of an oil cooler of the cooling device; Figure 3 is a diagrammatic side view in the direction of the arrow Ill of the oil cooler in Figure 2, and Figures 45 and 6 are in each case sections taken along the lines IV-IV or V-V or VI-VI in Figure 2.

The oil cooling device 10 shown diagrammatically in Figure 1 is intended particularlyfor vehicles in order to cool their lubricating oil, operating oil or other pressurised oil. The cooling takes place in conventional manner by means of heat exchange with water, for example cooling water, which is drawn off from the normal engine cooling system and passed through the oil cooling device transversely with respect to the flow of oil.

The oil cooling device 10 has an oil cooler 11,the details of which are not shown in greater detail, particularly with regard to cooling plates 12 (shown in Figure 2) and the water supply and discharge arrangements. The cooling plates 12 can for example be constructed as flat nests of tubes. The oil cooler 11 is provided with a bottom oil inlet connector 13 on one side and oil outlet connector 14 on the other side. The two connectors 13 and 14 are integrally cast into the housing when the latter is cast.

As shown in Figure 1, at least one further oil cooler in the form of an auxiliary cooler 15 is connected in parallel with the oil cooler 11. For connection of the auxiliary cooler 15 to the oil cooler 11, this latter is constructed in the manner described hereinafter.

The oil cooler 11 has a by-pass pipe 16 which quite generally branches off the oil feed to the oil cooler 11 which is indicated by the arrow 17. When the auxiliary cooler 15 is not connected, in other words during single cooler operation, the passage through, or outlet from, the by-pass pipe 16 is closed. In the case of the multi-cooler operation illustrated, a part, for example more or less half, the quantity of oil fed in the direction of the arrow 17 is, before it passes through the oil cooler 11, capable of being diverted via the by-pass pipe 16 to the parallel connected auxiliary cooler 15. For this purpose, the auxiliary cooler 15 is provided with a feed connector 18 which is connected to the by-pass 16 in a manner to be described hereinafter.

The by-pass pipe 16 is constituted for example by a pipe 19 which extends as an independent liquid carrying pipe outside the heat exchange parts of the oil cooler 11, i.e. outside of and past the cooling plates 12.

In the region of the oil inlet connector 13, connection and branching of the by-pass pipe 16 occurs as follows. As Figure 4 in particular shows, the by-pass pipe 16 has a branch pipe 20 which is an integral component of the oil inlet connector 13 of the oil cooler 11. The branch pipe 20 is produced together with, i.e. is in other words integrally cast with, the oil connector, when the latter is cast. The branch pipe 20 branches off the service pipe 21 of the oil inlet connector 13. Branching occurs at an angle to the service pipe 21. The angle of inclination between branch pipe 20 and service pipe 21 is substantially the same as the branching angle at which the other inlet pipe 22 which is fed by the service pipe 21 and the introduces the rest of the flow of supplied oil into the oil cooler 11.This angle of inclination is for example an obtuse angle and amounts for example to 135". As Figure 4 shows in particular, the throughflow cross-section of the by-pass pipe 16 is of the same size as that of the branch pipe 20. Furthermore, the throughflow cross-section of the inlet pipe 22 is more or less the same size as that of the service pipe 21. It can furthermore be seen that the through flow cross-section of the branch pipe 20 and by-pass pipe 16 is markedly smaller than that of the service pipe 21 and inlet pipe 22.In consequence, of the oil which is fed to the oil cooler 11 to be cooled, only about half the flow passes through the service pipe 21 and inlet pipe 22 and actually enters the oil cooler 11 to be cooled, passing through the oil cooler (arrow 23), while the other more or less half the quantity of oil is branched off, as indicated by the arrow 24, from the service pipe 21 through the branch pipe 20 and into the by-pass pipe 16. If, as is not shown, the by-pass pipe 16 is closed on the throughflow side or at the outlet side, then it is ineffectual. Then the entire quantity of oil introduced at 17 to be cooled passes through the oil cooler 11.

As shown particularly in Figures 5 and 6, the by-pass pipe 16 has its own outlet pipe 25 with, adjacent thereto, an outlet connector 26 which ends at an outlet orifice 27. The outlet connector 26 is inclined in relation to the outlet pipe 25 at the same angle as, on the inlet side, the branch pipe 20 is inclined in relation to the service pipe 21. The outlet pipe 25 and outlet connector 26 are both component parts which are integral with each other. In a region of the oil outlet connector 14 of the oil cooler, they are integrally cast therewith, whereby, in the direction of flow according to arrow 28 of the oil cooled in the oil cooler 11, they are located alongside the outlet pipe 29 of the oil outlet connector 14. The outlet orifice 30 of the outlet pipe 29 lies in a common plane with the outlet orifice 27 of the outlet connector 26.The outlet connector 26 and outlet pipe 29, like the outlet orifice 27 and outlet orifice 30, are divided from one another by a dividing partition 31. Common to both orifices 27 and 30 and thus to the outlet connector 26 and outlet pipe 29 is a connecting flange 32 on the oil outlet connector 14.

The pipe line 19 containing the by-pass pipe 16 is connected for example by integral casting to the branch pipe 20 at one end and to the outlet pipe 25 at the other. Oil diverted via the by-pass pipe 16 leaves the by-pass pipe 16 in the region of the oil outlet connector 14 of the oil cooler 11, in fact through the outlet pipe 25 and outlet connector 26 in the direction of the arrow 34.

As shown in Figure 1, there is connected to the connecting flange 33 of the oil inlet connector 13 a feed pipe 35 which supplies to the oil inlet connector 13 the oil which is to be cooled and which emanates from the oil pump.

Connected to the connecting flange 32 of the oil outlet connector 14 is for example a connection 36 with a branch 37 of an oil filter 38. The branch 37 communicates with the feed connector 18 of the auxiliary cooler 15 via a pipe 39. The return connector 40 of the auxiliary cooler 15 is connected to a return pipe 41 which leads back again to the oil filter 38, of which the diagrammatically indicated by-pass valve 42 is then opened. The oil filter 38 has an outlet 43 through which the oil cooled in the oil cooler 11 and auxiliary cooler 15 and subsequently cleaned in the oil filter 38 is carried away out of the oil filter 38 after which it is fed back again to the engine (not shown).

If it is not intended that the auxiliary cooler 15 be incorporated into the oil circuit of the oil cooler 11, the by-pass pipe 15 is closed for example at the outlet end, in the region ofthe branch 37. Furthermore, the connection leading from the return pipe 41 back to the oil filter 38 is likewise closed. It will be appreciated that during such operation conditions, additional oil coolers can nevertheless be accommodated at other places around the vehicle. If the auxiliary cooler 15 is connected according to Figure 1, then approximately one half of the oil which is to be cooled will be cooled in the oil cooler 11 while the other half is cooled in the auxiliary cooler 15. The latter can thereby be integrated into the engine or need not be disposed on the engine, but located as an auxiliary cooler. It can be located in all manner of locations on a vehicle, always in the minimum of space. It is advantageous that by reason of the by-pass pipe 16 and the branch, approximately half the quantity of the oil to be cooled is passed to the auxiliary cooler 15 so that the throughflow resistance is considerably reduced. In the final analysis, this leads to higher cooling efficiency per cooler.

Naturally, it is also of advantage that with the design described, one or a plurality of auxiliary coolers 15 can be installed subsequently at any time and at the minimum of cost. Improvement therefore merely requires the connection of the auxiliary cooler 15, but otherwise no other cost-intensive operations or accessories.

Claims

1. A heat exchange device for vehicles, including a first heat exchange for heat exchange between oil and water, the exchanger being provided with an oil feed having oil inlet and outlet connectors forthe oil, the device including at least one auxiliary heat exchanger connected in parallel to said first heat exchanger and a by-pass passage branching from the oil feed, the passage through which by-pass passage, or the outlet from which, is selectively closeable so that, when closed, only the first heat exchanger is effective or by means of which, a part of oil supplied by the oil feed can be diverted before it passes through the first heat exchanger to pass through said auxiliary heat exchanger which has an inlet feed connector connected to the by-pass passage.

2. A device according to claim 1 wherein the by-pass passage branches from the oil inlet connector of said first heat exchanger.

3. A device according to claim 1 or2, wherein the by-pass passage has a branch pipe which is an integral component part of the oil inlet connector of the first heat exchanger.

4. A device according to claim 3 wherein the branch pipe is integrally cast with the oil inlet connector.

5. A device according to claim 3 or 4 wherein in relation to the axis of a service pipe adapted to feed oil to said oil inlet connector said branch pipe extends substantially at the same angle as an inlet pipe, through which oil supplied in use, through the service pipe passes into said first heat exchanger.

6. A device according to claim 5, wherein said angle of inclination amounts in each case to about 135".

7. A device according to claim 5 or 6 wherein the throughflow cross-section of the branch pipe and of the by-pass passage, is smaller than that of said service pipe and said inlet pipe.

8. A device according to any one of claims 5,6 or 7, wherein the throughflow cross-section of the inlet pipe is substantially the same size as that of the service pipe.

9. A device according to any one of claims 3 to 8, wherein the throughflow cross-section of the bypass passage is substantially the same size as that of the branch pipe.

10. A device according to any on6 of claims 1 to 9, wherein the by-pass passage has an outlet pipe with an adjacent outlet connector, both of which are integral components the one with the other and are disposed in the region of the oil outlet connector of said first heat exchanger.

11. A device according to claim 10, wherein said outlet pipe and the outlet connector are disposed, in the outflow direction, beside an outlet pipe of said oil outlet connector of the first heat exchanger.

12. A device according to claim 11, wherein an outlet orifice of the outlet connector of the by-pass passage lies in a common plane with the outlet orifice of the outlet pipe of the first heat exchanger and is divided therefrom by a separating wall dividing the outlet connector of the by-pass passage from the outlet pipe of the first heat exchanger, the oil outlet connector having a connecting flange common to both orifices.

13. A device according to any one of claims 1 to 12, wherein the by-pass passage is formed by a pipe line which extends outside of the first heat exchanger as an independent pipe.

14. A device according to claim 13, wherein the said pipe line is connected, at one end to the branch pipe and at the other end to the outlet pipe of the by-pass passage.

15. A device according to claim 14 wherein said pipe line is integrally cast to said branch pipe and outlet pipe.

16. A heat exchange device for vehicles substantially as described herein with reference to, and as illustrated in, the accompanying drawings.