Hitachi, Ltd.

Sumiyoshi Takeda

Toshio Hatada

Takao Senshu

Akira Arai

Atsushi Matsuzaki

Fumio Harada

Yutaka Imaizumi

Hajime Futawatari

Kensaku Oguni

Hiromu Yasuda

Masaaki Itoh

Hideyuki Kimura

Minetoshi Izushi

Tatsuya Sugiyama

Minoru Sato

Naoki Shikazono

A heat exchanger composed by overlapping a plurality of heat exchanger units each of which is formed by inserting a plurality of fins over one or a plurality of heat transfer tubes. The fins are worked so that a pair of opposed fins of the overlapped heat exchanger units are brought into contact with each other at one or more points. This heat exchanger constitutes an air conditioner when the heat exchanger units are overlapped in a direction of gravity.

Heat exchanger and air conditioner using same

In a cross finned tube heat exchanger including a multiplicity of side-by-side fin plates, and a plurality of heat transfer tubes extending through the fin plates at least in one row to provide a serpentine flow passage for a heat transfer medium which exchanges heat with another heat transfer medium flowing across the surfaces of the fin plates, a multiplicity of stepped louvers are formed on the wall of each fin plate between the adjacent heat transfer tubes of the same row. The stepped louvers each extending in a direction at right angles to the direction of air flow across the surfaces of the fin plates include at least one tilting rise wall and may differ from one another in shape depending on their positions. The stepped louvers on each fin plate may be arranged in the form of waves or uniform in height with respect to the direction in which each fin plate extends. The adjacent stepped louvers have edges varying in vertical positions.

Heat exchanger

A cross-fin tube type heat exchanger having a large number of parallel fins and a plurality of heat transfer tubes extended through and fixed to the fins, so that heat may be exchanged between a first heat exchanging medium flowing through the heat transfer tubes and a second heat exchanging medium flowing along the surfaces of the fin, across the walls of the heat transfer tubes and through the fins. In the portions of each fin between adjacent heat transfer tubes of the same row, formed are a number of slits perpendicular to the direction of flow of the second heat exchanging medium. Each elongated section defined between each pair of adjacent slits is bent along its breadthwise bisector line and is raised in the form of a bridge to constitute an upwardly convexed louver element. The upwardly convexed louver element may have a cross section with an obtuse apex angle, or may have an arcuate cross section. The successive louver elements are arrayed in the direction of flow of the second heat exchanging medium in a manner of corrugation, or alternately staggered in the heightwise direction so that the edges of adjacent louver elements may be staggered in the heightwise direction. The fins having louver elements thus constructed cause a turbulency of the flow of the second heat exchanging medium to effectively prevent boundary layers of the latter from growing, thereby to ensure a higher efficiency of the heat exchange. Also increased stiffness or rigidity of the fin is obtained thanks to the provision of upwardly convexed louver elements.

Cross-fin tube type heat exchanger

Growing community of inventors

Shimizu, Japan

Sumiyoshi Takeda