WO2006010463A1

WO2006010463A1 - Plate heat exchanger

Info

Publication number: WO2006010463A1
Application number: PCT/EP2005/007509
Authority: WO
Inventors: Michael Seils; Hans Weitzenbürger; Monika Koschmann; Beate Rosner; Ewald Schneider
Original assignee: Deutz Aktiengesellschaft
Priority date: 2004-07-22
Filing date: 2005-07-12
Publication date: 2006-02-02
Also published as: ATE430296T1; EP1769207B1; EP1769207A1; DE502005007198D1; DE102004035448A1

Abstract

The invention relates to a plate heat exchanger (1) comprising a plurality of fluid guide channels (2) which are mounted in a parallel position with respect to each other through collecting channels (4a, 4b), wherein said guide channels (2) have a pair of plates (3a, 3b) which a mutually sealingly assembled by the edges thereof, distance pieces are provided in the collecting channels (4a, 4b) area between the plates (3a, 3b) inside the guide channels (2), spacers (6) are provided outside of said guide channels (2), the collecting channels (4a, 4b) are sealingly connectable to fluid channels (13) in a housing (12) and are closed on the opposite ends, the plate heat exchanger (1) is fixable to the housing (12) by means of screws (11), the plates (3a, 3b) are embodied in such a way that they dimensionally taper in the direction of the collecting channels (4a, 4b) and at least one screw (11) is provided near said collecting channels (4a, 4b) externally with respect to the plates (3a, 3b), respectively.

Description

Plate heat exchanger

DESCRIPTION

The invention relates to a plate heat exchanger, in particular for reciprocating internal combustion engines, with a number of guide channels for a fluid, which are connected in parallel to each other by collecting ducts, wherein the guide channels comprise a pair of plates which are sealingly ver¬ together at their edges , In the region of the collecting channels between the plates within the guide channels spacers and outside the guide channels spacers are provided and wherein the collecting ducts on fluid channels in a housing sealingly connectable bar and are sealed at the opposite end and the plate heat exchanger by means of screws on the housing can be fastened.

Such a plate heat exchanger is known from EP 0 470 200 B1. In this plate heat exchanger, the plates have a substantially rectangular shape in a plan view, which are rounded at the narrow sides. Within these narrow sides spacers and spacers are provided between the plates, which connect to the plates in the region of the collecting ducts End sheets. Both the end plates and the spacers and spacers completely fill the arcuate narrow sides of the plates and have through holes for screws, with which the plate heat exchanger on a Brennkraft¬ machine or a housing of an internal combustion engine anschraub¬ bar. If the plate heat exchanger is arranged on the internal combustion engine or on a housing in such a way that it flows through in the longitudinal direction, then the plates with spacers and spacers filling the full width of the heat exchanger form a broad barrier for the heat exchanger on its narrow side flowing liquid, so that even if the cover of the housing is laterally expanded, an unfavorable flow through the plate heat exchanger is given, the heat exchanger performance is impaired.

Furthermore, the plate heat exchanger is firmly clamped by the holes leading through the complete heat exchanger, which also lead through the plates forming the guide channels, to the housing or the internal combustion engine, so that thermal stresses can arise, which then increase the service life of the plate heat exchanger affect.

Furthermore, the screws must be sealed as they pass through the internal spaces of the plate heat exchanger.

Finally, it is expensive to produce the complete heat exchanger penetrating holes for the screws.

The object of the invention is to improve a generic plate heat exchanger to the effect that it provides a higher heat exchanger performance, in particular when it is hindurch¬ flows through. He should continue to be sealing, but not so rigidly arranged on the housing or the internal combustion engine that stresses arise. Finally, he should also be cheaper to manufacture.

The object of the invention is achieved in that the plates are rejuvenated in the direction of the collecting channels in their dimensions. Are formed and that in addition to the collecting channels außen¬ half of the plates at least one clamping screw is provided. As a result of this configuration, it is achieved that the plate regions surrounding the collecting channels are designed substantially narrower with spacers and the spacers, so that a good flow through in the longitudinal direction of the heat exchanger is possible. Both the rejuvenation of the plates contributes to the minimum dimension required for the collecting ducts and the arrangement of one or more screws outside the narrow side of the plates, which counteract only a small flow resistance of the liquid flowing through the plate heat exchanger.

Advantageously, the plate heat exchanger outside the sealed ends of the collecting ducts, ie on the opposite end of the connection to the fluid channels side, each a yoke plate, which is fastened by means of two screws on the housing. As a result, the plate heat exchanger is pressed sufficiently firmly against the housing or the internal combustion engine, but there is no forced operation, especially in the region of the sealing surfaces to the fluid channels, which could cause a distortion of the plate heat exchanger. The yoke plate can be placed externally both during installation on the plate heat exchanger, but it can also be attached to the plate heat exchanger, in particular soldered. The distance between the screw holes in the yoke plate is so far away from the sealing surfaces between the plate heat exchanger and the housing or the internal combustion engine that no Ver¬ adaptation is to be feared.

Instead of the yoke plate may each be provided on the housing facing the ends of the collecting channels a mounting plate and connected to the plate heat exchanger. This Befestigungs¬ plate serves to seal and the attachment of the heat exchanger to the housing. The mounting plates also have lateral Eyelets in which short screws are arranged. Even if the fastening plates are thus screwed to the housing and a certain forced fixing takes place, the plate heat exchanger arranged above and freely movable nevertheless has sufficient possibilities for stretching and deformation.

In a further embodiment of the invention, it is proposed that the plates, as seen in plan view, have substantially parallel outer edges, from which taper edges originate on both sides. Advantageously, the angle between the parallel outer walls and the tapering edges is approximately 20 to 30 °, in particular 25 °, and the tapering edges run into a radius between 18 and 28 mm, preferably 23 mm, around the axis of the collecting channels , As a result, a sufficient cross section for the collecting channels and also a sufficient compressive strength in the area of the collecting channels is achieved and nevertheless only one column of approximately 46 mm width directed counter to the liquid is produced, so that a sufficient flow cross section is provided laterally on both sides is made available, which only if long screws are provided, is impaired by these relatively thin screws. With short screws in connection with the fastening plates, there is no impairment whatsoever.

The plate heat exchanger has on the housing-side end of the collecting channels each a sealing plate when using yoke plates and long screws or a respective mounting plate, which can be brought into operative connection with at least one each mounted on the housing sealing ring. The sealing plates and the mounting plates are sealingly connected to the plate heat exchanger, preferably with this soldered. As a result, a sealing surface is provided which permits different expansions between the plate heat exchanger and the housing. In order to provide a simple assembly with little adjustment effort, it is proposed that the openings in the sealing plates adjoining the collecting channels are each smaller than the dimensions of the associated fluid channels in the housing, so that precise alignment of the opening in the sealing plate with the dimensions of the fluid channel is not important. Of course, it is clear to the person skilled in the art that the opening in the sealing plate is sufficiently large in order to ensure good flow through the plate heat exchanger. The dimensions of the fluid channel are therefore oversized for the amount of fluid passing through.

It has proven to be favorable and sufficient if the kreiszy¬ lindrisch shaped fluid channel has a diameter of 28 mm when a circular cylindrical opening in the sealing plate or a kreis¬ cylindrical cross section of the collecting channels have a diameter of 20 mm.

In a further embodiment of the invention, a bridge is provided outside the verschlos¬ senen ends of the collecting channels, which is secured by screws to the housing. The bridge is a one-piece fastening part, which rests preferably on the upper plate of Plat¬ tenwärmetauschers and can be particularly easily aligned, for example by appropriate design of the bridge with centering to the plate heat exchanger. Preferably, this bridge is attached to the housing with four screws, but it may optionally be sufficient to provide only two diagonally opposite screws on the collecting channels. The attachment of the plate heat exchanger with above the upper flap arranged yoke plates or the bridge also has the advantage that correspondingly long screws are used, which also have a corresponding large elongation. This large stretch provides high security against loosening the screws during normal operation. In an alternative embodiment, a spring element is provided outside the closed ends of the collecting ducts, which is supported on a lid covering the plate heat exchanger and presses the plate heat exchanger against the housing. This spring element can be provided centrally in the middle of the plate heat exchanger between the two collection channels. Preferably, however, two spring elements are provided which are each arranged in the region of the collecting channels between the uppermost plate of the plate heat exchanger and the lid. The one or more spring elements are preferably fixed to the plate heat exchanger or the cover by a suitable device, so that during assembly a defi¬ ned position is ensured. The length of the spring elements is dimensioned such that in the unloaded state, the fastening screws of the cover can be inserted straight into the corresponding threaded holes in the housing and exert at full Eindre¬ hen of these screws in the threaded holes, the spring elements such a pressure that the plate heat exchanger against ^• the housing is pressed. The screws, which are necessary in the attachment with yoke plates or bridge can basically be omitted when using the spring element düng, but it is vorgese¬ with these screws centering to attach to the housing, the centering cooperate laterally with the sealing plates and ensure a defined mounting position of Platten¬ heat exchanger.

Finally, in an alternative embodiment, a central fastening element which engages in the fluid channel can be used in each collecting channel. This fastening element is inserted through the collecting channel from the side facing away from the housing, wherein then of course at this point - ie in the uppermost plate - an opening is provided which is closed after installation with a sealing plug. The fastener may be formed as a hollow screw, which on a support flange of the bottom plate rests. Alternatively, the screw may extend through the entire collection channel and be supported on the outside of the top plate. In this embodiment, the otherwise required lid can be integrated into the hollow screw. For an unobstructed flow of oil between the collecting channels and the Kühl¬ spaces of the plate heat exchanger corresponding Übertrittsöff¬ openings are inserted into the hollow screw. This design has the advantage that - as in the attachment with at least one spring element - the flow around the plate heat exchanger with cooling water is further improved because no flow disturbing screws traverse the entire cooling water space. Also in this embodiment, it is provided with the correspondingly smaller-sized screws centering on the Ge housing to fasten, the centering laterally interact with the sealing plates and ensure a defined mounting position of the plate heat exchanger. This ensures that the banjo bolts can be easily mounted.

In a further embodiment, guide devices, for example in the form of catch plates, are attached to the plate heat exchanger, which are aligned with the flow channel from which the cooling liquid is supplied. These guide devices are designed so that they cause a particularly intensive and efficient flow through the plate heat exchanger with the liquid. In this case, the guide devices may be formed straight or laterally biased on the lid, so that the liquid supplied is inevitably passed through the plate heat exchanger. The length of the guide devices is optimized depending on the design.

For further explanation of the invention reference is made to the drawings, in which embodiments of the invention are shown in simplified form. Show it: 1 is a perspective view of a plate heat exchanger with screws inserted,

2 shows a partial section through a housing with cover of a combustion engine and side view of the plate heat exchanger,

3 shows a section through the lid and the housing with partial section through the plate heat exchanger according to the line A-

A in Fig. 2,

4 is a partial plan view of the lid with a dashed darge plate heat exchanger,

Fig. 5 is a partial plan view of the lid as shown in FIG. 4, wherein lateral guide devices are ange¬ introduced to the plate heat exchanger and

6 shows a section through the cover as in FIG. 3 with an alternative fastening

In FIGS. 1 to 4, as far as shown in detail, 1 generally designates a plate heat exchanger which has a larger number of guide channels designated by 2, which are composed of plates 3a and 3b. The guide channels 2 are connected to each other at the ends of the plates 3a and 3b by means of collecting channels 4a and 4b, so that the guide channels are shown connected in parallel to each other in terms of flow. Between the plates 3 a and 3 b 2 spacers 5 are inserted within the guide channels and spacers 6 are provided between the plates 3 a and 3 b outside the guide channels. The plates 3a and 3b, the spacers 5 and the spacers 6 are connected to each other soldered, so that results in a compact plate heat exchanger. The plates 3a and 3b have on the surfaces of the plates distributed nubs 7, which serve to increase the stability and the improvement of the heat transfer between the plate heat exchanger 1 flowing around the liquid and the plate heat exchanger 1 durch¬ flowing fluid. To the plate 3a which is fully visible in FIG. 1, a sealing plate 9 is soldered to the plate 3a in the region of the collecting channels 4a and 4b, a yoke plate 10 being soldered to the opposite side in the region of the collecting channels 4a and 4b. The yoke plate 10 has lateral eyelets which laterally project beyond the collecting channels 4a and 4b. Screws 11 are guided through the eyelets, which are screwed into a housing, not shown, of an internal combustion engine (not shown). A fluid channel 13 is formed in each case between the threaded holes in the housing 12 of the screws 11 and is connected to a fluid circuit, not shown, of the internal combustion engine. Around the fluid channels 13 around 12 grooves are incorporated in the housing, in which O-rings 14a and 14b are used. These O-rings 14a and 14b are in operative connection with the sealing plates 9, so that in conjunction with the bias of the screws 11, a tight connection of the collecting channels 4a and 4b to the fluid channels 13 results. In order to facilitate a simple alignment of the plate heat exchanger 1 on the housing 12, the cross sections of the fluid channels 13 are larger than the cross sections of the collecting channels 4a and 4b or of the openings in the sealing plates 9, so that assembly tolerances between the plate heat exchanger 1 and the housing 12 or different Deh¬ voltages can be compensated to each other.

On the end faces of the plate heat exchanger (see FIGS. 2 and 4) flow channels 15 are incorporated in the housing 12, through which a liquid is supplied and removed, which flows around the plate heat exchanger 1 on its outer surfaces. Narrow spacers within the guide channels and narrow spacers outside the guide result from the tapered edges denoted by 16, which are drawn together with respect to the outer edges 17 of the plates 3a and 3b to a small radius of the plates in the region of the collecting channels 4a and 4b Channels, so that only a relatively thin column of fluid from the flow channels 15 opposes and a favorable flow along the plate heat exchanger 1 is given. The screws 11 impede the flow only slightly, since there are passages between the screws and the spacers 6 (see FIG. 3, left side). For guiding the liquid between the flow channels 15 along the plate heat exchanger 1 and between the plates 3a and 3b, the plate heat exchanger is surrounded by a cover 18, which is sealingly connected to the housing 12.

Fig. 5 shows the same section as Fig. 4, here in addition to the plate heat exchanger 1 to the outer edges 17 side and / or upper guide devices 20 are mounted, which are aligned with the feeding flow channel 15 in. The guide devices 21 can - as shown - be formed straight or also create the side walls or the roof wall of the lid 18 under tension.

6 shows an alternative attachment method, wherein the plate heat exchanger 1 is pressed against the housing 12 by a spring element 19, which is arranged between the plate heat exchanger 1 and the upper part of the cover 18. LIST OF REFERENCE NUMBERS

1 plate heat exchanger

2 guide channels

3a, 3b plates

4a, 4b collection channels

5 spacers

6 spacers

7 pimples

9 sealing plates

10 yoke plates

11 screws

12 housing

13 fluid channels

14a, 14b O-rings

15 flow channels

16 rejuvenation edges

17 outer edges

18 lids

19 spring element

20 guide device

Claims

Plate heat exchanger A NSPR Ü CHE

1. Plate heat exchanger (1) with a number of guide channels (2) for a fluid which are connected in parallel to one another by collecting channels (4a, 4b), wherein the guide channels (2) comprise a pair of plates (3a, 3b) have at their edges sealingly connected to each other, wherein in the region of the collecting channels (4a, 4b) between the plates (3a, 3b) within the guide channels (2) spacers (5) and outside the guide channels (2) Abstands¬ wherein the collecting channels (4a, 4b) are sealingly connectable to fluid channels (13) in a housing (12) and closed at the opposite end, and the plate heat exchanger (1) is secured to the housing by means of screws (11). 12) is fastened, characterized in that the plates (3a, 3b) in the direction of the collecting channels (4a, 4b) are formed tapering in their dimensions and that in addition to the collecting channels (4a, 4b) outside of the plates (3a , 3b) at least one screw each Be (11) is provided.

2. Plate heat exchanger (1) according to claim 1, characterized in that outside the closed ends of the collecting channels (4a, 4b) each have a yoke plate (10) is provided, which is fastened by means of two screws (11) on the housing (12).

3. Plate heat exchanger (1) according to claim 1, characterized in that at the housing-side end of the Sam¬ melkanäle (4a, 4b) each have a mounting plate is provided, which mit¬ means of two screws on the housing (12) is attached.

4. Plate heat exchanger (1) according to one of claims 2 or 3, characterized in that the yoke plates (10) and the fastening plates are connected to the plate heat exchanger (1), preferably soldered.

5. plate heat exchanger (1) according to claim 1, characterized in that the plates (3a, 3b) in plan view ge see substantially parallel outer edges (17) auf¬ have, from which on both sides tapered edges (16) go out.

6. Plate heat exchanger (1) according to claims 1 or 5, characterized in that the angle between the parallel outer edges (17) and the Verjüngungsrändern (16) is about 20 to 30 °, in particular 25 °.

7. Plate heat exchanger (1) according to any one of claims 1, 5 or

6, characterized in that the tapering edges (16) in a

Radius of 18 to 28 mm, preferably 23 mm, about the axis of

Outflow collecting channels (4a, 4b).

8. Plate heat exchanger (1) according to any one of claims 1 or 2, characterized in that the plate heat exchanger (1) ge¬ on the housing side end of the collecting ducts (4a, 4b) each have a sealing plate (9) having at least one each on the housing (12) mounted sealing ring (O-rings 14a, 14b) can be brought into operative connection.

9. Plate heat exchanger (1) according to claim 8, characterized in that the sealing plates (9) at the Plattenwär¬ exchanger (1) sealingly attached, preferably are soldered thereto.

10. Plate heat exchanger (1) according to one of the preceding An¬ claims, characterized in that the to the collecting channels (4a, 4b) an¬ closing openings in the sealing plates (9) or the fastening plates are each smaller than the dimensions of zugeord - Neten fluid channels (13) or vice versa.

11. Plate heat exchanger (1) according to claim 10, characterized in that the collecting channels (4a, 4b) and / or the openings in the sealing plates (9) and the mounting plates are circular cylindrical with a diameter of about 20 mm and the fluid channels ( 13) are also formed at least at their the Plattenwärme¬ exchanger (1) facing the ends of a circular cylinder with a diameter of about 28 mm.

12. Plate heat exchanger (1) according to any one of claims 1 and 5 to 11, characterized in that outside the closed ends of the collecting channels (4a, 4b), a bridge is provided, which is fastened by means of screws (11) on the housing (12) ,

13. Plate heat exchanger (1) according to any one of claims 1 and 5 to 11, characterized in that outside the closed ends of the collecting ducts (4a, 4b) at least one spring element (20) is provided, which overlap at a plate heat exchanger supports the lid (18) and presses the plate heat exchanger (1) against the housing (12).

14. Plate heat exchanger (1) according to any one of claims 1 and 5 to 11, characterized in that in each collecting channel (4a, 4b) a central fastening element is inserted, which in each case in the FIu- idkanal (13) engages.

15. Plate heat exchanger (1) according to one of the preceding Ansprü¬ surface, characterized in that on the plate heat exchanger (1) guide devices (20) are mounted, which are aligned with the flow channel (15).