DK141345B - Heat exchange roller with an outer sheath and an inner sheath. - Google Patents

Description

/ fv OD PUBLICATION 141345 F 26 B 13/18 DENMARK, i ,,, ntc |, F c 13 / So • (21) Application No. 2188/67 (22) Filed on 25 · Apr. 19 ^ 7 (23) Le bed 25 apr. 1967 (44) Application made and __ „, _ Q.

the presentation of the letter was announced. February 1 900 DIRECTORATE OF THE PATENT AND TRADEMARKET (30) Priority begwetfre «ton

Apr 28 1966, 5777/660 SE

(71) Scandinavian appliance industry, Aktiebolaget Saiap, 6 Koepmansgatan, TTalkenberg, SE.

(72) Inventor: Karl Axel Bertil £ arreby, 6 Koepmansgatan, Falkenberg, SE.

(74) Full during the proceedings:

Larsen & Birkeholm Patent Office A / s.

(54) Heat exchanging roller with an outer sheath and an inner sheath.

The invention relates to a roller of the kind specified in the preamble of claim 1.

In such known rollers, where the helical metal rail is attached to the inner sheath, it is important that the contact to the outer sheath is good. Thus, the heat transfer effect is highly dependent on this contact. However, when the outer sheath is interchangeable and when it is also possible at the same time to adjust the position of the outer sheath, it is difficult to maintain or ensure good contact between the metal rail and the outer sheath. The result of poor contact between these two machine elements will be, partly that the resulting clearance will cause leakage of the heat transfer medium, whereby the flow and heat transfer will be uneven, and partly that the metal rail will not act as heat or cooling ribs, whereby the actual heat transfer area is reduced.

The object of the invention is therefore to provide a structure, thereby ensuring a good contact between the metal rail and the outer sheath. The roller is thus peculiar to the measures specified in claim 1. Hereby, a suitable resilient suspension of the metal rail can be obtained, which makes it possible to replace the outer casing with another outer casing and further to adjust the position of the outer casing without disturbing the contact of the metal rail.

According to the invention, the rail may consist of a strip of steel, suitably spring steel. This results in a good resilient and heat transferring effect at once.

According to the invention, the support layer may consist of fiberglass reinforced resin, suitably of polyester or rubber. This results in a good and robust construction.

25

An advantageous embodiment of the roller is characterized by that of claim 4. In this way, the support layer can be made more resilient, thereby increasing the safety of obtaining the correct position.

30

Finally, according to the invention, the outer casing may be provided at its interior with a helical groove for receiving the radially outer edge of the guide rail. Thereby, the seal between the outer casing and the rail is increased, ensuring a smoother heat transfer. Admittedly, a roller structure with a helical groove of this kind is known from the specification of U.S. Patent Nos. 234-1519. However, the roller known therefrom is not of the present kind, since its outer casing is not interchangeable. When this measure thus known has not hitherto been used in form 3

U136S

connection with rollers of the present kind is probably due to the fact that it has not been possible to manufacture the machine elements with the necessary tolerances. The technique according to the present invention makes it possible to transfer the known technique to rollers with interchangeable outer sheath.

The invention is explained in more detail with reference to the drawing,. wherein FIG. 1 shows an embodiment of a roller according to the invention, partially cut in longitudinal section; FIG. 2 is an end view of the roller; FIG. 3 is a partial longitudinal section through one end of the roller during assembly; FIG. 4 is a partial sectional side view of a roller according to another embodiment of the invention; FIG. 5 shows, on a larger scale, a portion of this roller, 25 in longitudinal section, and fig. 6 is a perspective view of the outer casing showing the arrangement of the guide rail on the helical member.

30

The roller shown in the drawing is intended to be designed as a cooling roller with an outer diameter of e.g. 500 mm and with water as a cooling medium.

4 141345

The outer casing 1 and inner casing 2 of the roller are thought to be formed of a rather thin plate, with a thickness of e.g. 4-6 mm, rolled to cylinder shape with a welded length seam. The seam is sanded after welding, so that the sheaths 1 and 2 become evenly exterior. Optionally, the sheath after welding may undergo a rolling operation. Conveniently by welding, the inner sheath 2 is secured by welding the shaft pin 3 of the roller, by means of spokes 4, so that the inside of the inner sheath becomes accessible between them. The shaft pins 3 are provided with a bore 5 with which they communicate with the annular space 6 between the sheaths 1 and 2 by means of pipes 7, which also serve as spokes.

In the gap 6 between the sheaths 1 and 2, at both ends of the roller are inserted two spring rings 8 and 9, which are provided with a transverse slit and which have different diameters. These rings are made of steel or similar material. The largest spring ring 8 has an outside diameter which is only slightly smaller than the inner diameter of the outer sheath 1. The smallest spring ring 9 has an inner diameter which only slightly exceeds the outer diameter of the inner sheath 2. The radially facing surfaces 10 and 11 of the spring rings 8 and 9rs, respectively, are tapered so that the axial inner end of the rings becomes thicker than their outer end. In the space between the spring rings 8 and 9 there is inserted a sealing ring 12, whose radially outer and inner surfaces are tapered with a conicity corresponding to the conicity of the surfaces 10 and 11 of the spring rings 8 and 9. The ring 12 is provided with a plurality of bores 133 whose shaft line 50 is parallel to the longitudinal axis of the roller. Through the bores 13 pass with plenty of clearance bolts 15 with head 14, which bolts are screwed into a nut ring 16. Between the nut ring 16 and the spring rings 8 and 9, an annular sealing 17 of rubber or another suitable elastic material is arranged.

141345 5

Externally around the inner sheath 2, according to FIG. 1 and 2, a support layer 18 is provided of a suitable and quite strong and also heat insulating material. Such a material is e.g. fiberglass reinforced, e.g. polyester plastics. This is wound into a ribbon around the inner sheath to form a fairly smooth, cylindrical sheath. Around this plastic sheath, a high-end strip of steel, suitably spring steel, is wound so that it extends helically from one end to the other end. This guide rail 19 is given an outside diameter that exceeds the inner diameter of the outer sheath 1 somewhat, e.g. 1-3 mm. In addition, in the gap between adjacent windings and the guide rail, fiberglass-reinforced plastic is placed so that the rail with its radially seen inner edge 20 is housed in the support layer 18.

In the composition of the roller, the outer sheath 1 is displaced over the inner sheath 2, see fig. 3 as the windings of the guide rail 19 are bent slightly resiliently to the side. After the outer sheath is displaced to its exact position on the inner sheath 2, FIG.

1, in which position the guide rail 19 is pressed against the inside of the outer sheath 1 with a certain spring tension, the bolts 15 are tightened. This causes the rings 8 and 9 to expand towards the outer casing 1 and the inner cap 2, respectively, while providing the necessary sealing: at the ends of the roller by compressing the sealing rings 17. The refrigerant flows, as indicated by arrows in FIG. 1, through one shaft pin 3, in a helical path through the gap 6 between the support layer 18 and the outer sheath 1 and out through the opposite shaft pin 3 · The channel limited by the support layer 18, the guide rail 19 and the outer sheath 1 can be given a small cross section , which is why the flow rate of the refrigerant can be made quite large. Because of this and the good contact between the guide rail 19 and the outer sheath 1, the heat output to the refrigerant becomes good.

When replacing the outer sheath 1, it is pulled off in the same direction as it is inserted into the inner sheath 2.

35 6 141346

According to FIG. 4-6, the support layer 18 may consist of helical members 21. These members 21 may be made of mutually arranged rings or, as shown in FIG. 6, of a helically wound hose placed 5 on the inner sheath 2. The guide rail 19 supports with its radially inner edge 20 in a groove 22 in the helical member 21 or the hose. Conveniently, the groove 22 is reinforced with a generally un-shaped metal rail 23. In its radially outer edge 24, the rail 19 10 is inserted into a helical groove 25 on the inside of the outer casing 1.

When mounting one proceeds thus, see in this connection especially fig. 6, first the guide rail 19 is screwed into the outer 15 'sheath 1, and then the helical hose 26 is screwed in such a way that the rail 19 with its radially lower edge engages the groove in the hose. Conveniently, the hose 26 is not under internal pressure when mounted but is slack, so that the inner sheath 2 can be easily inserted. Through an inlet valve 27, FIG. 5, the hose 26's inner 28 is filled with a pressure medium, e.g. compressed air or a hydraulic medium, e.g. water or oil. Thereby, the groove 22 with the reinforcing rail 23 is pressed against the radially inner edge 20 of the guide rail 19 and this is pressed on its side with its radially outer edge 24 against the outer sheath 1 so that it receives good internal support. This printing also provides good sealing at both the outer edge 24 and the inner edge 20 of the rail 19, so that the medium flowing through the gap 6 is forced to follow the helical path formed by the guide rail 30 19 between the sheaths 1 and 2.

There is no leakage between the different turns of the track. In order to ensure correct position on the helical turns of the hose 26 on the inner sheath 2, fastening screws 29 with nuts 30 can be applied to the inner end of the screws 35. Alternatively, it is also possible to use the spring rings 9 to obtain such support for the ends of the helical member 21 at the ends of the roller that all turns are held in position on the inner sheath 2, if one end of the roller is to be mounted only after filling with the pressure medium 5 . In this case, the fastening screws 29 can be saved and the seal thereby improved.

The embodiments shown and described are exemplary, and the various parts of the roller can be constructively altered in a number of ways within the scope of the claims. In the drawings, the roller is shown to be provided with only one guide rail 19. However, several such can be discussed, so that several channels extend in a helical path within the outer sheath 1.

Instead of steel or metal, the guide rail 19 may be formed with a strip of resilient plastic, e.g. polythene.

The support layer 18 may also be formed of rubber. The invention can, of course, also be adapted with heat rollers, whereby the heat transfer medium can be hot water or steam. For the helical members 21, car tire grade rubber may be selected or with a hardness somewhat greater than such quality, e.g. 70 ° shore.

Furthermore, some plastic can be conceived, which in many cases can advantageously be fiberglass reinforced. The helical member (s) need not be hollow.

However, such a design facilitates mounting as the slack members are easier to insert into place.