DE102007002492A1 - Plate type heat exchanger with a fixing surface and a heat exchange and/or cooling useful in production of electrical and electronic components has increased heat exchange efficiency - Google Patents

Abstract

Plate type heat exchanger with a fixing surface and a heat exchange and/or cooling surface. The fixing surface consists of a steel sheet 2,3,19) with corrugations or grooves and the heat exchange or cooling surface is a copper plate completely covering the corrugations or grooves, and welded to these by a laser weld seam (8-13). Independent claims are included for: (1) a cooling device for high capacity heat producing components (2) a method of producing the heat exchanger .

Description

The The invention relates to a plate-shaped heat exchanger with at least one mounting surface and a heat exchanger or cooling surface, one using heat exchangers constructed cooling device, and a method for production a heat exchanger.

From the utility model DE 202 00 484 U1 is a cooling device for components, in particular for electrical or electronic components known to be used in cabinets. Starting from air-cooled control cabinet coolers, whose cooling performance, however, remained inadequate for many high-performance components due to the air flow generated inside the cabinet and which previously had to be made relatively expensive, more intensive cooling in a small footprint is to be made possible.

The Principle of the cooling device according to the utility model is now in it, the heat loss of a high-performance component derive by contact cooling, without this one needed special forced ventilation inside the control cabinet. The heat sink according to the utility model is plate-shaped constructed and consists of a thermally conductive plate and an embedded therein, traversed by a cooling medium Heat exchanger. The thermally conductive plate was preferably made of aluminum and the cooling plate of a double plate made with two walls spaced apart, with channels in the space between the walls were formed in a groove-shaped depression, the run around meandering and flows through a cooling medium were.

In a particularly effective variant describes the utility model a heat exchanger equipped with copper pipes is, which are flowed through by a cooling medium. Preferably, these copper tubes are in a groove-like depression arranged over the entire length of the Cooling plate extends.

at This variant is in the embodiment of the utility model a cooling plate with transversely projecting at the edges Projections or webs shown in the corresponding trained groove edges of the groove-like depression engage. For attachment, a spring element is additionally provided, that between the bottom surface of the recess and this one facing side of the heat exchanger is arranged. Thereby can after the lateral insertion of the heat exchanger a Fixing the heat exchanger via the contact pressure the spring elements are effected.

The known device for utility model DE 202 00 484 Although compared to a cabinet cooler a smaller footprint, but it is relatively expensive to manufacture because of the required accuracy of fit in the undercuts for the interventions of the protruding at the edges of the cooling plate webs. In addition, this type of attachment is not gas and liquid tight, so that separate lines for the cooling medium are required. Here arise between the cooling lines unused dead space, whereby the overall efficiency (ratio of flow-through cooling surface to heat exchanger surface) is not optimal in the known cooling devices.

task The present invention is a heat exchanger and to develop a cooling device which is efficient Contact cooling with low space requirement and low production costs allows. The new heat exchanger should as possible a few items produced and formed gewichtsgarend so that even highly efficient lightweight components are produced can be used with a pressurized cooling or heat exchanger medium can be applied.

Further it is intended to specify a production method with which a pressure-tight, corrosion-resistant and weight-saving design for plate-shaped constructed heat exchanger can be realized.

These The object is achieved according to several embodiments explained in more detail. Show it:

1 Partial cross section through a heat exchanger constructed according to the invention

2 Perspective side view of a plate-shaped heat exchanger according to the invention

3 Partial cross section through a cooling device according to the invention

4 Perspective side view of a cooling device according to the invention

5 Process diagram for the production of a plate-shaped heat exchanger constructed according to the invention

To 1 the plate-shaped heat exchanger consists of a copper plate 1 , on both sides of each a steel sheet 2 . 3 with depressions 4 - 7 was applied. In the edge areas of the recesses are welds 8th - 13 arranged so that the interiors 14 - 17 the covered Ver depressions 4 - 7 are completely sealed. The interiors 14 - 17 can be filled with a pressurized heat exchanger medium. It is also possible connections for the supply and discharge lines in the wells 4 - 7 bring anywhere.

2 shows a perspective view of a heat exchanger according to the invention in a simplified representation. A copper plate 1 covers the recess 18 with a steel sheet 19 completely off, so after welding z. B. on the peripheral edge 20 the heat exchanger according to the invention is formed absolutely tight.

To initiate a print medium are connections 21 . 22 provided in the steel sheet in the area of the recess 18 can be attached with production technology simple means. The on the copper plate 1 and the steel sheet 19 indicated holes are used only for centering such. B. during pre-assembly. On the copper plate, various components can be attached, which are either cooled or heated. Also on the steel plate components can be attached directly, without the need for further aids.

The 3 and 4 show typical cooling devices for components from which z. B. continuously heat is to be dissipated. With similar devices components can be kept constant even at a certain temperature. In the steel sheets 23 . 24 are depressions 25 . 26 introduced in the form of beads, grooves or embossments. These recesses are formed as linear or annular channels, wherein the channels are straight, curved or alternating, sinusoidal or meandering. There are also several parallel channels possible.

From the back are the wells 25 . 26 with a copper plate 28 . 29 covered. On both sides of the recesses are circumferential welds 30 . 31 abgedeutet.

In 5 a process scheme is shown, after which at least one indentation of at least one depression in the steel sheet (s) takes place, forming an edge region of at least 1 mm in width.

After that becomes the recess with a copper sheet or a copper plate covered, which extends beyond the edge area. in the This can be followed by laser welding on the edge areas circulating around the recess, possibly pressure connections be introduced into the wells.

embodiments

• 1. Zunächst wird die Befestigungsfläche aus Edelstahl in eine Pressvorrichtung eingespannt und die Vertiefung mit Hilfe eines Prägewerkzeuges oder in einem Tiefziehvorgang hergestellt. Das eingesetzte Material bestand aus Edelstahl: 1.4571 X6CrNiMoTi17-12-2. Die Abmessungen der Befestigungsfläche betrugen: Länge 295 mm, Breite 62,5 mm, Dicke 1 mm. Länge der Vertiefung 260 mm, Breite der Vertiefung 28,5 mm, Tiefe 4 mm. Die Dicke des Edelstahlblechs kann im Bereich von 0,5 bis 2 mm, vorzugsweise bei 1 mm liegen. Die Wärmetauscher- bzw. Kühlfläche bestand aus einer Kupferplatte der Qualität Cu-DHP(SF-Cu) mit einer Dicke von 5 mm. Die Kupferplatte wurde so bemessen, dass die Vertiefung vollständig abgedeckt wurde und nur ein Randbereich mit der Befestigungsfläche überlappte.
• 2. In diesem Randbereich wurde mittels Laserschweißen eine Schweißverbindung wie folgt erzeugt: Die zu verbindenden Oberflächen wurden gesäubert, entfettet und durch Schleifen von der Oxidschicht befreit. Als Laser wurde ein Festkörperlaser eingesetzt mit den folgenden Parametern für Energieeintrag, Geschwindigkeit, Fokuslage, Schutzgas, Schutzgasmenge, Einstellung des Schutzgasrohres: Leistung P.: 2 KW Focus Z.: –0,5 mm Gesch. V.: 100 cm/min Schutzgas: 25 I Argon 4.6 Material: Stahlblech 1 mm 1.4571 und 5 mm Kupfer Cu DHP Material-Temperatur von ca.: 50°–60°C • Schutzgasdüse 8 Innendurchmesser • Leistungsrampen am Anfang auf den ersten 10 mm Leistung erhöhen, indem die Geschwindigkeit verringert wird • Leistungsrampen am Ende auf den letzten 10 mm Leistung verringern, indem die Geschwindigkeit erhöht wird. Brennweite 150 mm Während des Schweißens hatte die Probe eine Temperatur von ca. 50°C, die Eindringtiefe des Laserstrahls wurde im Beispiel auf 2 mm eingestellt. Vorzugsweise liegt der Bereich für die Einschweißtiefe bei 20 bis 50% bezogen auf die Dicke des Kupferbleches, das im vorliegenden Fall eine Dicke von 5 mm aufwies.
• 3. Anhand von metallographischen Untersuchungen wurde festgestellt, dass eine besonders günstige Schweißverbindung unter folgenden Voraussetzungen erhalten wurde: Mischungsverhältnis Kupfer zu Edelstahl 1: 2 bis 3 Temperierung der Proben vor dem Schweißen auf Temperaturen kleiner 100°C, vorzugsweise kleiner 60°C Unter diesen Voraussetzungen ist ein Optimum an mechanischer Festigkeit und Korrosions-Widerstand zu erreichen. Wichtige Faktoren sind hierbei: a) Geringe Korngrenzensprödigkeit b) Porenfreies, homogenes Schweißgefüge

The inventive method for producing a plate-shaped heat exchanger having at least one mounting surface and at least one heat exchanger surface or cooling surface is carried out as follows:

• 1. First, the mounting surface made of stainless steel is clamped in a pressing device and the recess produced by means of a stamping tool or in a deep drawing process. The material used was stainless steel: 1.4571 X6CrNiMoTi17-12-2. The dimensions of the mounting surface were: length 295 mm, width 62.5 mm, thickness 1 mm. Length of the recess 260 mm, width of the recess 28.5 mm, depth 4 mm. The thickness of the stainless steel sheet may be in the range of 0.5 to 2 mm, preferably 1 mm. The heat exchanger or cooling surface consisted of a copper plate of the quality Cu-DHP (SF-Cu) with a thickness of 5 mm. The copper plate was sized so that the well was completely covered and only one edge area overlapped with the mounting surface.
• 2. In this edge region, a welded joint was produced by means of laser welding as follows: The surfaces to be joined were cleaned, degreased and freed from the oxide layer by grinding. As a laser, a solid-state laser was used with the following parameters for energy input, speed, focus position, inert gas, inert gas, adjustment of the inert gas tube: Power P: 2 KW Focus Z .: -0.5 mm Gesch. V: 100 cm / min shielding gas: 25 l argon 4.6 material: sheet steel 1 mm 1.4571 and 5 mm copper Cu DHP material temperature of approx .: 50 ° -60 ° C • protective gas nozzle 8 inner diameter • power ramps at the beginning on the first 10 Increase power by decreasing speed • Decrease power ramps to the last 10mm at the end by increasing the speed. Focal length 150 mm During welding, the sample had a temperature of about 50 ° C, the penetration depth of the laser beam was set to 2 mm in the example. Preferably, the welding depth range is 20 to 50% based on the thickness of the copper sheet, which in the present case had a thickness of 5 mm.
• 3. On the basis of metallographic investigations, it was found that a particularly favorable welded joint under the following Vo Mixing ratio of copper to stainless steel 1: 2 to 3 Tempering of the samples before welding to temperatures below 100 ° C, preferably below 60 ° C Under these conditions, an optimum of mechanical strength and corrosion resistance can be achieved. Important factors are: a) Low grain boundary brittleness b) Non-porous, homogeneous weld structure

5

A

molding of at least one recess each in the steel sheet (s) a border area, at least 1 mm wide

B

Cover the wells with a Cu plate / plate until over the Rim area reaching

C

Laser welding, at the edge areas surrounding the recess, possibly introducing of pressure connections

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 20200484 U1 [0002]
• DE 20200484 U [0006]

Claims (10)

Plate-shaped heat exchanger with at least one mounting surface and a heat exchanger or cooling surface, characterized in that the mounting surface of at least one recess in the form of a bead, groove, etc. ( 4 . 5 . 6 . 18 ) Having steel sheet ( 2 . 3 . 19 ) and the heat exchanger or cooling surface of a copper plate ( 1 ), which completely covers the recess and with this over a circumferential around the edge of the recess weld ( 8th - 13 ) connected is. Heat exchanger according to claim 1, characterized in that that the weld formed as a laser weld is. Heat exchanger according to one of the preceding Claims, characterized in that the laser weld a mixed structure of copper to stainless steel in relation from 1 to 2 to 3.5. Heat exchanger according to one of the preceding Claims, characterized in that the through the recess formed cavity with a heat exchanger or cooling medium is filled. Heat exchanger according to one of the preceding Claims, characterized in that the heat exchanger or cooling medium is a pressurized medium, wherein the connections for an inlet and outlet of the Open the pressure medium in the recess of the steel sheet. Heat exchanger according to one of the preceding Claims, characterized in that on both sides of the heat exchanger or cooling surface depending on a mounting surface is arranged, each with at least one recess for the inclusion of the heat exchanger or cooling medium is equipped with the indentations of the between them arranged copper plate completely covered and over one each around the recess edge circumferential weld attached to this. Heat exchanger according to one of the preceding Claims, characterized in that each of the recesses is formed as a line or annular channel, wherein the channels straight, curved or alternating (sinusoidal, meandering) and the open channel side of the copper plate completely is covered, with the channel edges with a circumferential Welded seam sealingly connected to the copper plate. Cooling device for components, in particular for heat generating high performance components with at least one mounting surface and a cooling surface, characterized in that the fastening surface one with at least one recess in the form of beads, grooves or embossed steel sheet and the cooling surface consists of a copper plate that completely covers the depression and with this over a circulating on the edge of the depression Weld is connected, the heat-generating or dispensing parts (components) can be mounted directly on the copper plate are. Process for producing a plate-shaped construction Heat exchanger with at least one mounting surface and at least one heat exchanger or cooling surface, characterized in that the fastening surface a steel sheet, in the at least one recess as a line or annular channel with straight, curved or is formed in an alternating course, that the pits covered with a copper plate, several surrounding the recesses, narrow marginal areas arise, and that in the orbiting Narrow border areas a gas and liquid density Connection between steel sheet and copper plate by laser welding is produced. Process for producing a plate-shaped construction Heat exchanger according to the preceding claim, characterized characterized in that the penetration depth of the laser beam into the copper plate in the range of 20 to 50% based on the thickness of the copper plate lies.