Heat exchanger accessory for electronic circuit cabinets

Claim 1

Dust-sealed heat exchanger to cool dust-free air cooling air, for association with, or assembly to an electronic circuit cabinet (0, 50) having first (4, 5) and second (7, 8) blower means for circulating air; first means (10a) defining a cooling air flow circuit in communication with ambient air and second means (10b) defining a dust-free air flow circuit in air flow communication with the interior of the cabinet, said air flow circuits being separated in dust-free sealed relation with respect to each other; comprising the combination of a package of essentially rectangular identically stacked plates (20), each having oppositely located edge portions projecting in a first direction and at right angles from the major plane of the plate to form side flanges (22, 23) and having a further side portion projecting from the major plane of the plate at a right angle to form an end flange (27); one (23) only of the side flanges being shorter than the other to form a cut-out or notch (26) adjacent the end flange (28); said plates being assembled in said package with adjacent plates being reversely oriented so that the cut-out or notch (26) of adjacent plates will be at respectively opposite end portions of the package of the plates; stiffening ribs (24, 28) formed at the marginal end portions of said flanges and extending in a plane parallel to the major plane of an adjacent plate, the stiffening ribs being bonded to a next adjacent plate at the side opposite said first direction thereof to provide dust-tight sealing engagement therewith; said package being applied to the cabinet with the plates extending at right angle to a wall thereof; a first manifold box (3) positioned at an end portion of said package of plates and retaining said first blower means (4, 5); a cooling air flow communication opening (2) communicating with ambient air formed in said first manifold; a second manifold box (6) positioned at the other end of the package of plates and retaining said second blower means (7, 8); a dust-free air flow communication opening (9) communicating with the interior of the cabinet, said package being oriented such that the plates which are open at the end portion and in air flow communication with the first manifold have their cut-outs or notches (26) facing ambient air, and adjacent plates, which are open at the end portions and in air flow communication with the second manifold have their cut-outs or notches facing the interior of the cabinet, the plates with their respectively differently positioned cut-outs or notches (26) separating said air flow circuits while providing for heat exchange through the thickness thereof; and a cover plate (30) closing off the flanges of the final plate of the package.