DK150957B - HEAT TRANSMISSION ROLL AND PROCEDURE AND MACHINE FOR ITS MANUFACTURING - Google Patents

Abstract

The invention concerns a roll (12) comprising two superposed webs (6, 7) of material one (6) of which is formed with transverse ridges (10). At the ridge bases and tops are formed indentations (22). The other web (7) is provided with ribs (27) which are positioned in nesting relationship in the indentations, whereby the webs are secured to one another. The invention likewise concerns a method and a machine for manufacturing rolls of this kind.

Description

150,957th

in

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a roller for heat transfer and consisting of two coil-wrapped material webs wound around one core, one of which has transverse waves arranged at equal distances and the other material web has longitudinal ribs.

It is known to produce rollers for rotary heat exchangers by winding a plane and a corrugated web of metal foil, usually aluminum foil, to one another, whereby the two webs are joined to each other by means of a two-component or multicomponent binder 10. The winding takes place in such a way that the inner ends of the two webs are secured to a rotatably driven core sleeve. The smooth web is removed from a supply roller on a brake spindle. In this way, the webs are wound into a roll under a certain tensile stress 15 of the smooth web stock roll. As the torque of the core sleeve increases as the diameter of the wound roller increases, a situation will occur in which the traction of the smooth web due to the braking action of the supply roller causes the glue connection between the 20 smooth web and the waves in the corrugated web to break, one or more of the bonds becomes unrelated to the other windings. There is thus a risk that the entire roll may collapse when moved to a curing oven to cure the binder. Admittedly, after sufficient bursting of the adhesive bond, sufficient amounts of the binder may remain on the corrugated web's waveband and thus attach it to the smooth web, but the binder on the smooth web at the original attachment locations to lie in the space between the 30 peaks, causing the disadvantage that the flow cross-section of the air through the rotary roller of the heat exchanger is reduced.

Such rolls are found e.g. disclosed in German patent specification DE 2 029 399, which relates to a cross-flow heat exchanger 2 150957 (the angle between the two currents, however, differs somewhat from 90 °). The heat exchanger of this invention is flat, i.e. it does not form a wheel, and with this kind of heat exchanger there is no reason to design it as a wheel. There is no mechanical locking between the various layers included in the heat exchanger.

Another known construction is described in U.S. Pat. No. 3,901,309, wherein the ribs in a material web 22 are provided with indentations 22a formed to form channels 10 extending at a certain angle to the channels which forms the corrugation 22. The indentations do not intend, as in the present invention, to form a mechanical lock between the various webs which are included in the wheel. As is apparent from the text of the patent, it is intended that these webs should be fixed to one another by means of gluing. Another construction is disclosed in U.S. Pat. No. 3,931,854 which relates to a flat countercurrent heat exchanger which is clearly different from the assembly of the present invention in that it shows no heat exchanger wheel and has no mechanical locking between the various webs. etc. U.S. Patent No. 3,712,372 discloses a cross-flow heat exchanger with mutually perpendicular channels for the various media, also in this case there is no question of forming a heat exchanger wheel or providing a mechanical lock between the various webs. , which is included in the heat exchanger wheel. Swedish Patent Specification No. 423,750 discloses an assembly for transferring warnings between a gaseous medium and a liquid medium to be spaced apart. It is stated in claim 1 that the layers fall into pairs in pairs, but this is to form a narrow fluid passage. The grooves mentioned in claim 1 of this patent serve to stiffen the layers and cause flow resistance. This patent therefore belongs to a technique other than the present invention and does not intend to have a heat transfer between two media flowing through the same channel at different times. It does not deal with the construction of a wheel or the locking of the material webs relative to each other by means of a mechanical lock.

German Patent No. 2,243,653 relates to a conventional heat exchanger wheel, ie. state of the art in filing the present application, which has been discussed in detail above.

Swedish Patent No. 405,642 relates to a flat cross-current heat exchanger which is clearly different from the present invention. This patent does not cover heat exchanger wheels with mechanical locking etc.

Heat exchanger wheels of known construction are manufactured according to known and generally used technique in such a way that a 15-fold and a flat aluminum web are wound around each other and glued together at the top and bottom of the folded web. The manufacture of such wheels is cumbersome. The glue must be placed exactly on the tops of the folds, and these must not be stretched out during the winding. If the folded web is subjected to stretching forces, e.g. upon the winding of the next winding of the flat web, the top or bottom of the folded web can be displaced and come next to the bond. A small defect in the adhesive joint can cause the entire cast wheel to break.

25 In addition, when curing the wheel there is a risk that the glue will flow out and block the ducts in whole or in part.

The adhesive used in the prior art is epoxy or polyurethane adhesive. This causes major work-environment problems, as well as high demands on ventilation and protection of the workers.

4 150957

Another well-known problem of the prior art arises from the fact that the adhesive bond with aluminum in a humid environment has a poor long-term strength. After a time of use, the adhesive compound can come loose, even though it was flawless from the beginning.

5 A technical approach proposed to solve this problem is to place spokes in grooves milled into the wheels. Another approach is to cut the wheel into segments and mount these segments in self-supporting frames.

Both of these methods are expensive, impractical and involve 10 urational preparation.

The heat exchanger wheel of the present invention aims to eliminate the aforementioned disadvantages of the prior art by mechanically interlocking the two aluminum webs. No glue is required.

The invention aims to avoid the sizing operation altogether, while at the same time striving for a substantially larger heat transmission than in heat exchangers equipped with rollers of the prior art type.

This object is achieved according to the invention by a construction of 20 rolls according to the following claims. In addition, the invention comprises a method of making the roll according to the invention as well as a machine for carrying out the method, which method and machine are characterized in the following independent claims and subclaims.

The invention will be explained in more detail below with reference to the drawing, in which: FIG. 1 is a schematic side view of a machine according to the invention for producing rolls of two joined material webs; FIG. 2-4 are large-scale cross-sections of three different stations for forming one material web; 5 is a side view of the embodiment of FIG. 4; FIG. 6 and 7 are horizontal views of the roll-up station of the roller with its one end plate in different positions; 8 on a larger scale is a vertical longitudinal section through the winding station at the beginning of the winding; FIG. 9 shows the same at a later stage of the winding; FIG. 10 shows, on an even larger scale, a section through the outer edge of the rotatably driven end plate of the winding station; FIG. 11 is a perspective view of a portion of the roll; FIG. 12 is an enlarged cross-sectional view of a portion of the roller; FIG. 13 is a longitudinal sectional view of the roll along the line XIII-XIII of FIG. 12, and FIG. 14 shows the roller, viewed from the end surface, partly in section.

At the two ends of an elongated frame 1 are rotatably mounted two 15 spindles 2 and 3, each carrying a stock roll 4 and 5 respectively of a web of smooth aluminum foil 6 and 7 respectively. The frame 1 also carries a station 8 for corrugating the material web 6, a station 9 for producing impressions in the peaks and valleys of the waves 10 in the corrugated 20 web, and a station Ile for winding both lanes 6 and 7 into a roller 12.

The corrugation station 12 consists of two rotatably driven intermeshing gear-like rollers 13, 14, between which the web 6 is guided to form transverse waves 10 therein.

After the corrugation station 8 is the station 9 in which impressions are formed in the peaks and valleys of the waves 10. The station 9 consists of two toothed rollers 15,16 and two with peripherally extending beads 19, see fig. 5, which corresponds to 30 in the shape of recesses 20 at the top of teeth of tooth rolls 15 and 16, as the material passes the rolling gap formed between rollers 15 and 17 and 16 and 18, respectively, waves 10 are provided with depressions 22 in both peaks and valleys. .

6 150957

The impressions 22 in the peaks and valleys of the waves 10 are offset by a half pitch relative to each other, see fig. 13, for the internal flow area to be constant along the entire formed channel A.

5 After the station 9 is placed a support plate 23 on which the corrugated web 6 slides freely during the feeding. The web 6 further passes through a pair of guide or master rolls 24,25 before the winding station 11. These rollers 24,25 regulate e.g. the rotational speed of the rollers 13,14 in relation to the winding speed of the roll 12.

The smooth web 7 is fed from its supply roll 5. It runs through a pair of cooperating rollers 26 corresponding to the rollers 17, 18 which are provided with circumferentially extending rollers to provide the web 7 with rifles 27. These rifles 27 have the same division as the impressions 22 in the peaks and valleys of the waves 10. The web 7 then passes a heater 28 suitably consisting of two nozzles connected to a hot air source not shown. Before the web 7 reaches the winding station 11, it is controlled in the lateral direction by means of a control device 29 that the grooves 27 of the web 7 are laid down in the impressions 22 of the web 6, since the web 7 is heated, during cooling it will contract. a secure fixing of the rolls 12 incoming webs 6 and 7 is obtained relative to each other.

The winding station 11 includes two coaxial, rotatably mounted end plates 30 and 31. The distance between the end plates 30 and 31 in the working position is approximately equal to the width of the material webs 6.7. The width of the web 7 provided with grooves 27 should be insignificant, suitably 2 mm, 30 smaller than the width of the corrugated web 6. One end plate 30, with its shaft 32, is pivotally mounted in a bearing 33 on the rack 1 and is driven by a sprocket 34 on the outer end of shaft 32. On the opposite end of sprocket 34, shaft 32 is formed with a pin 35 on which For example, one end of a core sheath 36 may be slid onto which the webs 6 and 7 are to be wound. The core sleeve 36 can be clamped onto pin 35 by an expandable clamping sleeve 37 which is axially penetrated by a bolt 39 provided with a head 38 having an external thread engaging with the head 38. an internal thread in a rotatable but axially displaceable tension bush 40 inside the shaft 32.

The second end plate 31, with its shaft 41, is pivotally mounted in a bearing 42 at the outer end of an arm 43 pivotally about a vertical shaft 44 on the frame 1 by means of a handle 45. In the pivoted position, fig. 7, 8 and 9, 10 engages a pin 46 on the shaft 41 at the free end of the core sheath 36 (the left end of Figures 8 and 9).

The end plate 30 is provided on the side facing the end plate 31 with a round 47 of rubber or similar elastic material, which is secured by screws 48 along its inner and outer edges to the end plate 30. In addition, there is a displaceable bearing. large number of pistons 49, each having a head 50, located in a recess 51 in the end plate 30 within the round plate 47. With their free ends 52, the pistons 49 project from the back 53 53 of the end plate 30.

At the rotation of the end plates 30 and 31, towards the back 53 of the end plate 30 rolls a roller 54 pivotally mounted on a shaft 55 at the lower end of a guide rod 56 having a guide 57 which is vertically displaceable in a guide groove 58 in a stand 59 disposed over the bed 33. The guide rod 56 is connected to an arm 60 extending down into the gap 61 between the end plates 30, 31 and at the lower end of which is rotatably mounted a pressure roller 62 which is approximately level with roll 54.

30 After the arm 43, FIG. 6, is swung out and a core casing 36 with one end is shot on the pin 35 and by means of the clamp bushing 37 is clamped thereon, the ends of the material carriers 6 and 7 are secured by means of binder to the core casing 36. The machine drive is started and the winding of the core sheath 36 is initiated by its rotation and the end plates 301 s • 8 150957 and 31. The two webs 6 and 7 are laid on one another with the grooves 27 interfering with the recesses 22. As one winding after the other is applied to the core sheath 36, the pressure roller 62 which includes the arm 60 and the guide rod 56 is lifted with the roller 54. When the pistons 49, during the rotation of the end plate 30, the roll 54 passes, by the latter being pressed against the pivot 47, which is thereby slightly curved into the space 61 between the end plates 30 and 31. Thus, the most recently wound turns of the webs 6,7 are subjected to a side pressure and become 10 thereby being clamped between the end plates 30 and 31. This causes the traction of the shaft 32 to be transferred directly to these turns and the tensile stress in the groove 7 provided with a groove 27, which is held stretched by a brake on the spindle 3, is thus absorbed by the webs. 6.7 friction against end plates 15 and 30 The inner turns of the webs on the core casing 36 are thereby relieved. Thus, there is no risk of the already wound windings being pressed together.

After the roll 12 is wound and the outer winding 20 is connected to the next outer winding by means of binder, the heat 43 is again pivoted outward and the pressure on the clamping sleeve 37 is removed. The roll 12 can then be removed from the machine together with the core casing 36. A subsequent cooling of the roll 12 at room temperature causes the above-described fixing of the webs 6 and 7 relative to one another due to the contraction caused by the cooling of the rifles. 27 provided web 7. This fixation prevents the finished winding roll 12 from collapsing.

The grooves 27 and the depressions 22 cause the flow channels A of the medium flowing through the heat exchanger to receive it in FIG. 13. This form of the channels causes the area of the heat transferring surface to become larger and the flow through the channels A to be turbulent and not laminar. In a laminar flow which would occur if the channel's limiting surfaces were completely flat, the closest limiting surface seems to flow

Claims (8)

150957 media layer as an insulation which prevents the rest of the medium from coming into contact with this surface. The turbulent flow which will occur in the channels of the roll according to the invention causes a greater part of the flowing medium to come into intimate contact with the confining surfaces. This effect, as a result of the heat transfer surface of the channels A, due to the grooves 27, causes the heat transfer of the heat exchanger to increase considerably. The roller 54 next to the end plate 30 can be replaced with lugs carried by the guide rod 56. Alternatively, the second end plate 31 may also be provided with a ring 47 of elastic material. This towing shoe may be of such length and / or width that it depresses two or more pistons 49 simultaneously. Further, there are other ways of relieving the inner winding turns of the roller. An arrangement of pneumatic pistons can be envisaged, which transfers the draw directly to the outer winding of the roll. A heat transfer roller consisting of two about 20 core cores (36) wound on one another (6 and 7), one of them (6) having transverse waves (10) arranged equally spaced to form axial channels through the roller, and the second material web (7) has longitudinal grooves (27), characterized in that the waves (10) of the former web (6) are provided with impressions (22) with the same pitch both at the peaks and in the valleys. such as the grooves (27), in which indentations (22) the grooves on the second material web (7) intervene to form a mechanical lock between the two webs. A roller according to claim 1, characterized in that the indentations (22) in the peaks of the waves (10) are offset by a half pitch relative to the indentations (22) in the valleys. The method of making rolls according to claim 1 by winding on a rotary driven core sleeve (36) two material webs (6 and 7), one of which (6) has transverse waves (10) and the other (7). ) has longitudinal grooves (27), characterized in that at least one of the webs is guided so that the rifles (27) are inserted into the impression (22). Method according to claim 3, characterized in that the winding takes place between two end plates (30 and 31) rotating together with the core sheath (36), at least one of which is driven and that at least one of the material webs ( 6.7), suitably the web (6) provided with waves (10), during winding is clamped between the side plates (30 and 31) so as to be included therewith. Machine for carrying out the method according to claim 3 and having a winding station (11) to which are provided two material webs (6 and 7), one of which (6) has transverse waves (10), characterized in that: the machine includes members (26) which are adapted to produce longitudinal grooves (27) during the advance of the second web (7) and partly means (15-18) arranged for 20 under the first web (6). ) advancing to produce depressions (22) with the same pitch as the rifles (27) in both the peaks and valleys of the waves (10) in the web (6), and that the machine has means (29) arranged to control it. one or the other web (6,7) such that the grooves (27) in the one web (7) will engage the depressions (22) in the second web (6). Machine according to claim 5, characterized in that the means for producing the indentations (22) in the tops and parts of the waves (10) in the second material web (6) are formed by recesses (20) in the upper edges of the teeth (21). ) on a rotatably mounted toothed roller (16) and a peripheral bead (19) provided with a roller (18) parallel to the latter (16) so that the beads (19) on the latter roller (18) engage in the recesses (20) on the 35 toothed roller (16) during the rotation of the rollers, thereby forming a rolling gap for this material web (6). 150957 Machine according to claim 5, characterized by a rotatably driven end plate (30) having a shaft (32) on which one end can be pushed and clamped by a core casing (36), the opposite end of which is supported by a pin (46) on an opposed, rotatably mounted end plate (31), and by a means arranged to subject at least one of the webs (6,7) to a lateral pressure for clamping said web during the winding on the core sheath (36) the end plates (30 and 31), thereby including the web in the rotation of the end plates (30, 31). Machine according to claim 7, characterized in that a pressure roller (62) arranged to follow the position of the outermost winding of the roller (12) at all times is pivotally mounted on a movable arm (60) to and from the core sheath (36) along with a guide (57,58) together with a pressure means (54) adapted to give the outer winding a lateral pressure in the direction of the opposite end plate (31) and the driven shaft (32) end plate (30) has a portion (47) of rubber or similar elastic material, and that the thrust member (54) is constituted by a pressure roller (62) in its radial motion relative to the roller (12) as follows: roller (54) or the like, which is arranged to push said elastic portion (47) inwardly from the pressure roller (62).