Patent GB-912301-A (GB)
Title: Improved method for the manufacture of heat exchangers
Inventor: SZOTS GEZA
IPC: B21D53/08
Filed: 1959-03-06
Abstract: 912,301. Making heat-exchangers. ALTALANOS GEPTERVEZO IRODA. March 6, 1959, No. 7811/59. Class 83 (2). In assembling heat-exchangers comprising parallel tubes 2, Fig. 1, and fins 1 spaced by rings 7, the fins and rings are threaded on to mandrels 6, Fig. 2, and the tubes or assembly bars are assembled in a carrier, the mandrels then being aligned with the tubes or bars and the fins and rings slid from the mandrels on to the tubes or bars. If assembly bars are used, a further step of transferring the fins and rings on to tubes is required. If the bars are not used, temporary stiffening rods may be inserted in the tubes. On the exchanger the aluminium fins, which are each about half of the length of the exchanger, are divided into groups by stiffeners 4 and end plates 3 extending the full length of the exchanger. A dispenser for discharging the rings 7 into apertures 16 in bars 15, Fig. 5, has a funnel to receive and guide the rings into annular grooves 11, Fig. 3, in a rotatable drum 10 from which they are stripped by channelmembers 14 leading to the apertures 16. The bars are moved past the members 14 to fill each of the apertures, which correspond in number to the number banks of tubes. A release-plate 34 beneath the bars 15 is moved to align its banks of holes 34a with the apertures and allow the rings to fall through the holes on to the mandrels, where they come to rest on a stiffener 4. Electrical contacts (Fig. 9, not shown) operated by the presence of the rings 7 in the bars 15, control a signal lamp. A divided table 35a, 35b, Fig. 10, with slots to receive guides 36, supports the fin 1, which is pushed on to the mandrels 6 by collars 37 as the table-sections are separated and the guides 36 lowered. Rings and fins are assembled alternately to form a group, and the operations repeated for the remaining batch of mandrels on the charger. The tubes 2 spaced by rods 22, Fig. 13, are assembled in a slotted table, and the assembly collected by the carrier 23, Fig. 15. Openings 24a in hangers 24 of the carrier which are rotatable on rods 26, receive the tubes. Hangers 25 hold the tubes in the openings 24a and the hangers are also rotatable about their longitudinal axes to receive and to release the rods. The rods 22 are removed and the assemblage of tubes transferred in the carrier to a press, Fig. 17, where the mandrels 6 are aligned with the tubes by means of adapters (Fig. 19, not shown) inserted in the tube-ends. A ram 33 maintains pressure on the mandrels, through levers connected by a rod 32 which passes through slots in the ends of a box 30 engaged by a ram 38. The box engages a frame 31 which forces the group of rings, fins and a stiffener 4 off the mandrels and on to the tubes, the hangers 24, 25 being turned about their axes to release the ends of the tubes and retracted from the spaces between the tubes by rotation of the rods 26. The discharged charger is replaced by a loaded charger, and so on until all the groups of fins and rings have been assembled on the tubes. An end-plate 3 opposite that supported by the carrier 23 is then positioned on the tubes and the assembly compressed by the box 30, Fig. 20. The ends of the tubes (Fig. 21, not shown) are then expanded in the end-plates 3 and their intermediate portions in the rings and fins. A cradle 28 on the press raises the assembled heat-exchanger. In a modification, Fig. 24, the fins &c. 46 are stripped from the mandrels on to rods 39 which are located in vertical slots 41 in the carrier-plates 40 and spaced by bars 43. The press-strokes are 1¢ times the width of the groups of fins &c. 46, which are pushed along the rods by arms 44 pivoted on their actuator 45 so as to retract from the groups on return strokes of the press. The first group pushes the plates 41 along the rods 39 to an opening 47 where they are withdrawn, the bars 43 being withdrawn through side-openings. The assembled groups are compressed before they are transferred to the tubes. Two assembling machines may be operated singly by an hydraulic trolley-borne press (not shown) including a safety device which prevents operation of the press-motor if the trolley is not anchored securely at the site of one of the machines.