Abstract: A loose assembly of parts which are not secured is moved from a pallet on a conveyor to a banding station. The assembly may vary in size and a machine readable tag on the pallet bears the size information. A transfer apparatus reads the tag and adjusts a clamp size to fit the assembly. An elevator lifts the assembly from the pallet to the clamp and guide fingers hold the assembly together during the transit. The clamp is suspended from an overhead trolley which carries the clamp and assembly to the banding station where the assembly is released. A lift cylinder on the trolley raises the clamp to clear the assembly and the clamp is then returned to its position above the conveyor, lowered, and adjusted to receive another assembly.

Abstract: A machine with counter-rotating rotors moves heat exchanger plates two at a time with vacuum assist through paths which converge in a vertical mating plane. Arcuate guides engage the plate ends to control the plate path. The rotors are servomotor controlled to synchronously index the rotor in increments separated by dwell periods. After assembly the merged pairs drop between spaced guides into an assembly fixture. At a subsequent brazing operation each plate pair becomes a tube for carrying refrigerant.

Abstract: A method and apparatus for assembling heat exchanger elements includes a pallet comprising a frame and a plurality of blocks slidably aligned on each side of the frame with opposed pairs of blocks slotted to receive pairs of plates dropped into the pallet. Lead screws driven by servomotors and engaging the blocks position the blocks at the loading station and control the block spacing (determined at each station by the screw pitch) to allow plate insertion or to allow insertion of fin elements between the plates. To quickly move the pallet into the station auxiliary lead screws connected to the main screws engage the blocks of the pallet outside the loading station to assert positive controlled advancement force on the pallet.

Abstract: An apparatus for assembling heat exchanger elements includes a pallet comprising a frame and a plurality of blocks slidably aligned on each side of the frame with opposed pairs of blocks slotted to receive pairs of plates dropped into the pallet. Lead screws driven by servomotors and engaging the blocks position the blocks at the loading station and control the block spacing (determined at each station by the screw pitch) to allow plate insertion or to allow insertion of fin elements between the plates. To quickly move the pallet into the station auxiliary lead screws connected to the main screws engage the blocks of the pallet outside the loading station to assert positive controlled advancement force on the pallet.

Abstract: A method and apparatus for assembling heat exchanger elements includes a pallet comprising a frame and a plurality of blocks slidably aligned on each side of the frame with opposed pairs of blocks slotted to receive pairs of plates dropped into the pallet. Lead screws driven by servomotors and engaging the blocks position the blocks at the loading station and control the block spacing (determine at each station by the screw pitch) to allow plate insertion or to allow insertion of fin elements between the plates. To quickly move the pallet into the station auxiliary lead screws connected to the main screws engage the blocks of the pallet outside the loading station to assert positive controlled advancement force on the pallet.

Abstract: Serpentine heat exchanger tubes are formed with spaces smaller than the fins which must fit in the spaces, the tubes are elastically spread apart so that tubes can be inserted, and the tubes are then allowed to contract to grip the elements for good contact and to help maintain the assembly until a brazing operation. A machine for inserting the fins has spreader blades for insertion into the tube spaces remote from the tube bends, and including sets of blades which then are moved toward the bends to fully dilate the spaces to permit easy insertion of the fins.

Abstract: A continuously fed tube is momentarily halted at a cutting station and quickly cut by a rotating knife. The tube is continuously advanced from driving rollers to idler rollers and passes through interemdiate pinch rollers which are cam controlled in synchronism with the cutting process to bow the tube at a rate which causes the tube portion at the cutting station to briefly stop during cutting. The cutter includes a planetary gear set having a carrier rotatable about a central axis which carries a knife for rotation about another axis while it revolves about the central axis. The knife makes many rotations per carrier revolution but is in position to cut the tube during one of the rotations.

Abstract: A continuously fed tube is momentarily halted at a cutting station and quickly cut by a rotating knife. The tube is continuously advanced from driving rollers to idler rollers and passes through intermediate pinch rollers which are cam controlled in synchronism with the cutting process to bow the tube at a rate which causes the tube portion at the cutting station to briefly stop during cutting. The cutter includes a planetary gear set having a carrier rotatable about a central axis which carries a knife for rotation about another axis while it revolves about the central axis. The knife makes many rotations per carrier revolution but is in position to cut the tube during one of the rotations.

Abstract: A tube and center heat exchanger has header and tank assemblies formed of just two plates stacked and bonded together. One plate has apertures for receiving the tube ends, and the second plate is formed with a plurality of tank defining indentations in an interface thereof that interconnect selected ones of the tube ends to thereby connect all the tubes to define a serpentine flow path through the heat exchanger. The header and tank plates are stamped from flat sheet stock of braze clad aluminum, the necessary perforations, clinch tabs and indentations are formed and the plates are stacked and clinched into header and tank assemblies. The tube and center elements are assembled and the tube ends are inserted into the header and tank assemblies. The whole heat exchanger is then brazed to form the bonding between the plates as well as the other elements.

Abstract: A method and apparatus for assembling heat exchanger elements includes a pallet comprising a frame and a plurality of blocks slidably aligned on each side of the frame with opposed pairs of blocks slotted to receive pairs of plates dropped into the pallet. Lead screws driven by servomotors and engaging the blocks position the blocks at the loading station and control the block spacing (determined at each station by the screw pitch) to allow plate insertion or to allow insertion of fin elements between the plates. To quickly move the pallet into the station auxiliary lead screws connected to the main screws engage the blocks of the pallet outside the loading station to assert positive controlled advancement force on the pallet.

Abstract: A method for assembling heat exchanger plate pairs by snap fitting with counter-rotating rotors move heat exchanger plates two at a time through paths which converge in a vertical mating plane. Arcuate guides engage the plate ends to control the plate path. The rotors are servomotor controlled to synchronously index the rotor in increments separated by dwell periods. After assembly the merged pairs drop between spaced guides into an assembly fixture. At a subsequent brazing operation each plate pair becomes a tube for carrying refrigerant.

Abstract: Pairs of standard plates and special plates are assembled and inserted into a fixture along with side plates and intervening fins at respective assembly stations along a conveyor in accordance with a programmed order of insertion. The fixture separates elements already in place by a variable amount as needed to accommodate the insertion of each additional element. The insertion of fins is coordinated with the manufacture of the fins for direct insertion upon formation.

Abstract: Method and apparatus therefor for forming an inner tube and turbulator for a concentric tube heat exchanger from a stock length of tube comprising the steps of simultaneously mechanically forming a bell-shaped sealing and outer tube attaching section in the ends of the tube while also sealing the ends, applying hydraulic pressure to the interior of the tube to form outwardly projecting turbulator bumps in the tube at places located about and along the length thereof, and increasing the mechanical forming force with increasing hydraforming force so that the latter opposes the former and only their net force acts on the bell-shaped sections to maintain the sealing during the hydraforming to prevent coining of these sections.