Finned tube heat exchanger

A heat exchanger comprising:

• a plurality of fin plates spaced at regular intervals, arranged in parallel with one another and adapted to allow air to flow therebetween, each fin plate having openings arranged in a longitudinal direction thereof and a leading edge arranged perpendicularly to the air flow;
• and
• a plurality of heat exchanger tubes extending through the openings of said fin plates in a direction perpendicular to the planes in which said fin plates lie and being adapted to allow a refrigerant fluid to pass therein,
• each of said fin plates having a plurality of strips projected from the surface of said fin plates and extending perpendicularly to a direction in which air is to flow between said fin plates,
• said strips comprising first to fifth rows of strips arranged between the openings, which are disposed adjacent to one another, along the longitudinal direction of said fin plates in a parallel relationship,
• said first row of strips being located near the leading edge of said fin plates and being formed of two louverlike strips in a form of a trapezoid having a long side located on the upper stream of the air flow, each of said second to fourth rows of strips being formed of one bridgelike strip in a form of a rectangle, said fifth row of strips being formed of two louverlike strips in a form of a trapezoid having a short side located on the upper stream of the air flow,
• each of said first and fifth rows of strips having the long side cut to be projected upwardly, each of said second to fourth rows of strips having four sides, two opposing sides, facing the air flow, being opened by cutting and the other two sides being provided with leg portions for connecting said second to fourth rows of strips with said fin plates,
• said first to fifth rows of strips having a projecting height of about 1.0 mm and a width of about 1.0 mm,
• said first and fifth rows of strips being slanted at an angle of about 35.degree. with respect to said fin plates,
• said first, second, fourth and fifth rows of strips being formed on the same side of said fin plates, and said third row of strips being formed on the other side of said fin plates,
• said third row of strips being located substantially on a line between the centers of adjacent openings formed in said fin plates, and said first and second rows of strips being disposed in a symmetric relationship with said fourth and fifth rows of strips with respect to the center line of the third row of strips.