DE102015011241A1 - Heat exchanger for a cooling circuit - Google Patents

Abstract

The invention relates to a heat exchanger for a coolant flowed through by coolant, in particular for a coolant flow through an internal combustion engine of a motor vehicle, which heat exchanger is designed in a U-flow design, in which a plurality of axially parallel heat exchanger tubes (1) on opposite end faces in a Connection water box (3) and in a Umlenkwasserkasten (5) open, wherein the coolant flows from an inlet-side part box (7) of the connection water box (3) over a first half of the heat exchanger tubes (1) in the Umlenkwasserkasten (5) and from there in opposite flow direction via a second half of the heat exchanger tubes (1) in an outlet-side part box (9) of the connection water box (3) can be guided, and wherein the inlet-side part box (7) and the outlet-side part box (9) by means of a separating element (11) from each fluid-tight separated d. According to the invention, a loose bearing (17) is arranged between the two sub-boxes (7, 9) of the connection water box (3), by means of which the two sub-boxes (7, 9) in the longitudinal direction (y) of the heat exchanger tubes (1) independently of each other via clearances (.DELTA.y1 , Δy2) are displaceable, specifically to compensate for operational expansion of the length of the heat exchanger tubes (1).

Description

The invention relates to a heat exchanger for a cooling circuit through which coolant flows, in particular for a coolant flow through an internal combustion engine of a motor vehicle, according to the preamble of claim 1.

Such a heat exchanger can be integrated as a coolant radiator in an engine cooling circuit of a motor vehicle and is installed as such in a vehicle front end. The coolant radiator is flowed through by the wind, whereby the cooling water flowing through the coolant radiator is cooled.

From the DE 10 2006 060 603 A1 a generic heat exchanger is known, which is designed in a U-flow design, in which a plurality of axially parallel arranged heat exchanger tubes open at opposite end faces in a connection water box and in a Umlenkwasserkasten. In the cooling mode, the coolant is passed from an inlet-side part box of the connection water box over a first half of the heat exchanger tubes in the Umlenkwasserkasten and from there in opposite direction of flow over a second half of the heat exchanger tubes in an exit-side part box of the connection water box. The inlet-side sub-box and the outlet-side sub-box of the connection water box are decoupled from each other by means of a separating element fluid-tight.

Due to the swelling during driving flow or by regulating volume flow control valves in the engine cooling circuit, the heat exchanger tubes are subjected to thermal strains. In particular, the above U-flow construction thereby leads to a high thermal cycling of the tubes and a reduced component strength. Quickly controlling temperature control elements (energized thermostats, electromechanical control valves, etc.) can additionally have a negative effect on the service life of the component.

In the heat exchanger of the U-flow type, the hot heat exchanger tubes, with a correspondingly long length extension, adjoin colder heat exchanger tubes with a smaller length extension. Due to the rigidity of the water boxes, this leads to damaging mechanical stresses in the heat exchanger tubes.

The object of the invention is to provide a heat exchanger in which damage due to operational thermal pressure-train alternating stresses is avoided in a simple manner.

The object is solved by the features of claim 1. Preferred embodiments of the invention are disclosed in the subclaims.

The invention is based on the idea that, in departure from the prior art, the length expansions of the heat exchanger tubes should be allowed, whereby a thermal stress build-up in the heat exchanger can be avoided from the outset. Against this background, a movable bearing is arranged according to the characterizing part of claim 1 between the two sub-boxes of the connection water box. With the help of the floating bearing, the two sub-boxes can move independently of each other in the longitudinal direction of the heat exchanger tubes. In this way, a compensation of operational expansion of the heat exchanger tubes takes place, without resulting in train-pressure cycles of the heat exchanger tubes. The introduction of the floating bearing is preferably provided on the inlet / outlet side. Basically, the other side offers itself. In this case, however, technical measures must still be taken to transfer / forward the volume flow. This is not required on the inlet side due to the divider.

Thus, it is achieved by constructive measures that the hot heat exchanger tubes are mechanically separated from each other in the first half of the cold heat exchanger tubes in the second half. This is realized in that the inlet side and outlet side partial boxes of the connection water box are no longer rigidly connected to each other, but rather are connected to each other adjustable by means of the movable bearing.

Preferably, the floating bearing can be made rigid transversely to the longitudinal direction, that is, in particular in the vertical direction. This means that in the transverse direction no or only a greatly reduced clearance for the two sub-boxes is provided.

In the installed position, the heat exchanger can be part of a cooling package structure, which is composed of a number of individual components. By way of example, the cooling package structure can have a fan and a condenser, which can be mounted on the heat exchanger (main water cooler) or similar components. In this case, it is preferred if the floating bearing, the power transferring the two sub-boxes, viewed in the vertical direction together. This can be done in the installed position, a power transmission in the vehicle vertical direction between the two sub-boxes.

By way of example, the movable bearing can have a linkage, in particular a pivoting lever. The linkage can be pivoted at articulation points on the inlet-side sub-box and on the outlet-side sub-box. The articulation points of the linkage or the pivot lever define a lever longitudinal axis or a lever action direction. Preferably, the longitudinal axis of the lever extends in a non-coolant-flowed construction position in alignment in the vehicle vertical direction. To compensate for operational linear expansion of the pivot lever can shift the entry-side sub-box and / or the exit-side sub-box to the above-mentioned clearance with slight pivotal movement.

In an alternative embodiment, the movable bearing can be designed as a spring element. The spring element may be realized as an elastomeric bearing or as a rubber-metal bearing, which is designed in the longitudinal direction of the heat exchanger with a reduced bearing stiffness and transverse thereto with an increased bearing stiffness.

In a further alternative embodiment, the loose bearing may be formed as a rail guide, which is constructed of rail parts, which is fastened in each case to the inlet-side sub-box and the outlet-side sub-box. The facing rail parts may be telescopically adjustable in the longitudinal direction of the heat exchanger tubes. In contrast, the two rail parts can be performed largely free of play in the transverse direction.

The advantageous embodiments and / or further developments of the invention explained above and / or reproduced in the dependent claims can be used individually or else in any desired combination with one another, for example in the case of clear dependencies or incompatible alternatives.

The invention and its advantageous embodiments and further developments and advantages thereof are explained in more detail below with reference to drawings.

Show it:

1 in a schematic diagram of a heat exchanger in the U-flow design;

2 a detailed view of the heat exchanger, in which a floating bearing between the outlet-side part box and the inlet-side part box is indicated; and

3 and 4 each views according to the 2 with variants of the floating bearing.

In the 1 a heat exchanger is shown, which can be used as an example in a main engine radiator in an engine cooling circuit of a motor vehicle. In the installation position, the main water cooler is installed in the front of the vehicle and can be flown by the wind during driving. The 1 as well as the others 2 to 4 are made with a view to a simple understanding of the invention. Therefore, the figures are only roughly simplified representations that do not reflect a realistic construction of the main water cooler.

So is in the 1 the main water cooler with a plurality of axially parallel arranged heat exchanger tubes 1 built, which at their opposite end faces in each case in a connection water box 3 and in a diversion water box 5 lead. The Indian 1 shown main water cooler is designed in a U-flow design, in which the connection water box 3 in an entry-side upper part box 7 and in an exit-side lower part box 9 is divided. The two partial boxes 7 . 9 are over partitions 11 fluid-tightly decoupled from each other and a height offset .DELTA.a ( 2 or 3 ) spaced apart. The inlet-side sub-box 7 the connection water box 3 has an inlet nozzle 13 on, via which the coolant from an internal combustion engine in the inlet-side sub-box 7 and further over a first half of the heat exchanger tubes 1 in the deflection water box 5 to be led. In the Umlenkwasserkasten 5 there is a U-shaped flow deflection, wherein the coolant in the opposite direction of flow through the lower second half of the heat exchanger tubes 1 in the lower, outlet-side sub-box 9 the connection water box 3 is returned. From there, the cooled coolant flows through a drain port 15 back into the coolant channels of the internal combustion engine.

Like from the 1 As can be seen, the two sub-boxes are 7 . 9 the connection water box 3 not rigidly interconnected, but rather a floating bearing 17 that in the 2 is shown enlarged. Consequently, the floating bearing has 17 a pivot lever 19 on, at upper and lower pivot points 19 at the entry-side sub-box 7 and at the exit-side sub-box 9 is articulated. In the illustrated construction not flowed through by coolant, the pivot lever 19 vertically aligned, in such a way that the two points of articulation 21 , which define the course of a lever action direction or a lever longitudinal axis, in the vehicle vertical direction z are in alignment on top of each other.

In cooling mode, the upper half of the heat exchanger tubes 1 compared to the lower half of the heat exchanger tubes 1 heated much more, causing. the heat exchanger tubes 1 of the upper half and the heat exchanger tubes 1 the lower half are subjected to different length expansions. To compensate for these different length expansions of the heat exchanger tubes 1 can the inlet and outlet part boxes 7 . 9 in the 2 under slight pivotal movement S of the pivot lever 19 displaced by indicated freedoms Δy ₁ , Δy ₂ , without causing pressure-cycle alternation stresses of the heat exchanger tubes 1 comes.

Due to the alignment of the pivot lever in the vertical direction z 19 are the two partial boxes 7 . 9 , viewed in the vehicle vertical direction z, still connected to each other in a force-transmitting manner. That means that the floating bearing 17 in the vertical direction z is inoperative. In this way has the floating bearing 17 does not result in deterioration of the dimensional stability / strength of the main water cooler and the cooler package structure in which, for example, a fan and a condenser are mounted on the main water cooler.

In the 3 is an alternative embodiment of the floating bearing 17 between the two sub-boxes 7 . 9 shown. As a result, the floating bearing is 17 designed as an elastomeric bearing, which on the facing partitions 11 the partial boxes 7 . 9 is connected. The elastomeric bearing 17 is designed so that it is in the vehicle transverse direction, that is, the longitudinal direction y of the heat exchanger tubes 1 Has a reduced bearing stiffness and transverse thereto, that is in the vehicle longitudinal direction and in the vehicle vertical direction z has increased bearing stiffness.

In contrast, in the 4 the floating bearing 17 not designed as an elastomeric bearing, but rather as a rail guide with two mutually telescopically connected rail parts 23 . 25 educated. The rail parts 23 . 25 are each at the facing partitions 11 the partial boxes 7 . 9 tethered. In cooling mode, the two rail parts 23 . 25 the rail guide 17 freely adjustable in the vehicle transverse direction via the clearances Δy ₁ , Δy ₂ . The rail guide 17 is designed so that the two rail parts 23 . 25 are stored substantially free of play in the vehicle longitudinal direction and in the vehicle vertical direction.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006060603 A1 [0003]

Claims (7)

Heat exchanger for a cooling circuit through which coolant flows, in particular for a coolant flow-through cooling circuit of an internal combustion engine of a motor vehicle, which heat exchanger is designed in a U-flow design, in which a plurality of axially parallel heat exchanger tubes ( 1 ) on opposite ends into a connection water box ( 3 ) and in a Umlenkwasserkasten ( 5 ), wherein the coolant from an inlet-side sub-box ( 7 ) of the connection water box ( 3 ) over a first half of the heat exchanger tubes ( 1 ) in the Umlenkwasserkasten ( 5 ) flows and from there in the opposite direction of flow over a second half of the heat exchanger tubes ( 1 ) in a exit-side sub-box ( 9 ) of the connection water box ( 3 ) is feasible, and wherein the entry-side sub-box ( 7 ) and the exit-side sub-box ( 9 ) by means of a separating element ( 11 ) are separated from each other in a fluid-tight manner, characterized in that between the two sub-boxes ( 7 . 9 ) of the connection water box ( 3 ) a floating bearing ( 17 ) is arranged, by means of which the two sub-boxes ( 7 . 9 ) in the longitudinal direction (y) of the heat exchanger tubes ( 1 ) can be displaced independently of one another via free passages (Δy ₁ , Δy ₂ ), specifically to compensate for operational expansion of the length of the heat exchanger tubes ( 1 ). Heat exchanger according to claim 1, characterized in that the floating bearing ( 17 ) is executed transversely to the longitudinal direction (y), in particular in the vertical direction (z), that is, no or only a reduced clearance for the sub-boxes ( 7 . 9 ). Heat exchanger according to claim 2, characterized in that the floating bearing ( 17 ) the two sub-boxes ( 7 . 9 ) in the vertical direction (z) connects to each other in a force-transmitting manner. Heat exchanger according to one of claims 1, 2 or 3, characterized in that the floating bearing ( 17 ) a linkage, in particular a pivoting lever ( 19 ), which at articulation points ( 21 ) on the entry-side sub-box ( 7 ) and at the exit-side sub-box ( 9 ) of the connection water box ( 3 ) is articulated. Heat exchanger according to claim 4, characterized in that the articulation points ( 21 ) are arranged in alignment in the vertical direction (z), and / or that with slight pivoting movement (S) of the rod ( 19 ) the entry and / or exit sub-box ( 7 . 9 ) is displaceable by the clearance (Δy ₁ , Δy ₂ ). Heat exchanger according to claim 1 to 3, characterized in that the floating bearing ( 17 ) is a spring element, in particular an elastomeric bearing or a rubber-metal bearing, which in the longitudinal direction (y) of the heat exchanger tubes ( 1 ) has a reduced bearing stiffness and transversely to an increased bearing stiffness. Heat exchanger according to one of claims 1 to 3, characterized in that the floating bearing ( 17 ) is formed as a rail guide, which at each of the sub-boxes ( 7 . 9 ) cooperating rail parts ( 23 . 25 ), which in the longitudinal direction (y) of the heat exchanger tubes ( 1 ) to each other telescopically adjustable and in the transverse direction (z, x) are guided without play.

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