Heat exchange – Radiator core type – Deformed sheet forms passages between side-by-side tube means
Reexamination Certificate
1999-06-04
2001-01-09
Lazarus, Ira S. (Department: 3743)
Heat exchange
Radiator core type
Deformed sheet forms passages between side-by-side tube means
C165S175000, C165S176000
Reexamination Certificate
active
06170567
ABSTRACT:
TECHNICAL FIELD
The present invention relates to heat exchangers, for example, for use as air-cooled oil coolers, after coolers, inter coolers, radiators, etc.
BACKGROUND ART
Plate fin heat exchangers of the so-called drawn cup type which can be manufactured with a high efficiency are generally used as heat exchangers for use as air-cooled oil coolers or air-cooled after coolers for various industrial devices. The heat exchangers of this type comprise fluid channel members and fins which are arranged alternately in layers, the channel members being each composed of a pair of dishlike plates which are joined as opposed to each other. Each of the plates has at each of its opposite ends a header recessed portion which is shaped in the form of a cup by drawing and formed with a fluid passing hole in its bottom wall. The holes thus formed in the fluid channel members provide a header at each end of the heat exchanger.
In the case of the heat exchangers described, however, the plates are shaped by press work using a single kind of die, so that there arises a need to prepare another die anew when the length of the core portions, i.e., the length of the plates, is to be changed. Especially in the case of heat exchangers for industrial devices or apparatus which exchangers are fabricated in many kinds in a small quantity for each kind, it has been difficult to prepare plates of different lengths to meet the demands in view of the production cost of different dies.
In the case of the plate fin heat exchanger of the drawn cup type described, the cup-shaped header recessed portions of the plates have a reduced thickness smaller than the plate thickness owing to the drawing work, with the result that the headers become insufficient in pressure resistance, vibration resistance and corrosion resistance.
Conventional heat exchangers include those which comprise fluid channel members each formed by joining a pair of dishlike plates, or a dishlike plate and a flat plate, and annular header members each interposed between the corresponding ends of each pair of adjacent fluid channel members.
With such heat exchangers, the header members are superior to the header recessed portions of the plate fin heat exchanger of the drawn cup type in resistance to pressure, vibration and corrosion, whereas since the dishlike plates are similarly shaped by press work using a single kind of die, there arises a need to prepare another die anew when the length of the core portions, i.e., the length of the plates, is to be changed.
Heat exchangers are also available conventionally which comprise fluid channel members each composed of an intermediate plate having a channel forming slit and flat outer plates joined respectively to opposite sides of the intermediate plate, and annular header members each interposed between the corresponding ends of each pair of adjacent fluid channel members.
The heat exchangers of this type are inferior to plate fin heat exchangers of the drawn cup type in productivity, while there is a need to prepare another die anew when the length of the intermediate plates is to be changed. Additionally, if it is attempted to form a piping socket communication bore across two adjacent header members, for example, for connection to piping of increased diameter, the fluid channel member comprising three plates and having a relatively large thickness will offer resistance to the flow of fluid through the socket communication bore. It is therefore impossible to form the piping socket communication bore, consequently limiting the freedom to position the piping connection correspondingly.
An object of the present invention is to provide a heat exchanger which readily permits changes in the length of its core portions as demanded although comparable to plate fin heat exchangers of the drawn cup type in productivity and which comprises headers having high resistance to pressure, vibration and corrosion and is less likely to be limited in the freedom to position the piping connection.
DISCLOSURE OF THE INVENTION
The present invention provides a heat exchanger comprising a plurality of fluid channel members arranged one above another in parallel at a spacing and each composed of a pair of plates, each of the plates having a fluid passing hole at each of opposite lateral ends thereof and a channel portion extending over the entire length thereof between the end holes for forming a fluid channel, the pair of plates being joined with recessed surfaces of their channel portions opposed to each other to form the fluid channel member; and annular header members each interposed between each pair of adjacent fluid channel members at each of opposite lateral ends of the heat exchanger, each of the header members having upper and lower end faces each comprising a flat portion to be fitted to a flat portion of an edge of each plate defining the end hole thereof and a recessed portion to be fitted to a protuberant end face of the plate channel portion, the upper and lower end faces of each of the header members at each of the opposite lateral ends of the exchanger being joined to a peripheral edge portion of the plate immediately adjacent thereto and defining an opening formed by the end hole of the plate and an open end of the channel portion thereof for communication with the header member to form a header at each of the opposite lateral ends.
With the heat exchanger of the present invention, the plates and the header members are joined into an exchanger body, for example, by collective vacuum brazing, so that the heat exchanger is comparable to plate fin heat exchangers of the drawn cup type in productivity.
The plates of the heat exchanger each have a fluid passing hole at each of opposite lateral ends thereof and a channel portion extending over the entire length thereof between the end holes for forming a fluid channel, so that the length of the plates can be altered with extreme ease as demanded. The heat exchanger is therefore suited especially for use as heat exchangers for industrial devices which exchangers are to be fabricated in many kinds in a small quantity for each kind.
The annular header members for forming the header can be obtained, for example, by cutting a hollow extrudate having a relatively large thickness into blocks of predetermined size and forming a recessed portion partly in the cut end faces of the cut blocks. The header members are therefore easy to make and excellent in resistance to pressure, vibration and corrosion.
To be suitable, the material for the plates is a double-faced aluminum brazing sheet in view of bondability, whereas other metal may alternatively be used.
The annular header members can be obtained by cutting a hollow extrudate, for example, of aluminum (including an aluminum alloy, the same as hereinafter) having a relatively large thickness into blocks of predetermined size and forming a recessed portion partly in the cut end faces of the cut blocks. The header members are therefore easy to make and excellent in resistance to pressure, vibration and corrosion.
An outer fin, which is usually a corrugated fin, is interposed between each pair of adjacent fluid channel members of the heat exchanger. An inner fin, such as an offset fin or corrugated fin of the straight type, may further be inserted in the fluid channel of the fluid channel member. Side plates are disposed externally of the respective fluid channel members at opposite ends of the arrangement of channel members in layers with respect to the direction of arrangement, with a header member of the same shape as the header members interposed between each side plate and the channel member adjacent thereto at each lateral end of the exchanger. A piping socket is usually attached to each of these side plates. In this case, an outer fin is interposed also between each side plate and the fluid channel member adjacent thereto.
In the heat exchanger described, at least one of the opposite end holes of each plate is divided into front and rear portions by a striplike partition extending laterally, the channel portion of
Hasegawa Kaoru
Muramatsu Toshiaki
Nakada Keiichi
Armstrong, Westerman Hattori, McLeland & Naughton
Duong Tho
Lazarus Ira S.
Showa Aluminum Corporation
LandOfFree
Heat exchanger does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heat exchanger, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heat exchanger will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2498920