US2289097A

US2289097A - Heat exchanger for oil coolers

Info

Publication number: US2289097A
Application number: US392705A
Authority: US
Inventors: Howard F Brinen
Original assignee: Young Radiator Co
Current assignee: Young Radiator Co
Priority date: 1941-05-09
Filing date: 1941-05-09
Publication date: 1942-07-07
Anticipated expiration: 1959-07-07

Description

y 1942- H. F. B RINEN 2,289,097

HEAT EXGHANGER FOR OIL COOLERS Filed May 9, 1941 1N VEN TOR. H0m420 fi'Bem /Y BY as A 7' TOE/YE Y Patented July 7, 1942 HEAT EXCHANGER FOB OIL COOLERS I Howard F. Brlnen, Racine, Wis., assignor to Young Radiator Company, Racine, Wis., a company of Wisconsin Application May 9, 1941, Serial No. 392,705

3 Claims.

The present invention relates to means for controlling the temperature of internal combustion engine lubricating oil and is particularly adapted for use with aviation engines and is offered as an improvement over the design shown in a pending application John J. Hilt inventor, Serial No. 364,236, filed November 4, 1940.

An object of the present invention is to provide a conventional design having two headers and a number of preferably similar tubes forming operating connections therebetween and a multiplicity of closely spaced strip fins through which the tubes extend forming a unitary core.

Another object'of the present invention is to provide a conventional design having means whereby the lubricating oil is first passed through low resistance low heat transfer capacity tubes while at low temperature and then through a large number of high resistance tubes after the oil reaches a predetermined temperature.

The above objects are accomplished by providing a unitary core having a few front tubes of low heat transfer capacity and ofiering low resistance to the flow of oil therethrough and a large number of high resistance tubes in the rear and a partition between the front and rear tubes in one of the headers having a valve adapted to permit the oil when too viscous to pass through the high resistance tubes to pass through the low resistance tubes.

In my new design, I use tubes in the rear bank of tubes which are preferably similar to the front tubes but are provided with turbulence strips. In order to provide a high resistance path, I may provide a large number of very small tubes so hot oil will flow therethrough freely but the oil will not flow therethrough when chilled. Therefore it may be said that the lubricating-oil will be permitted to heat quickly after which it will pass through the rear bank of tubes and be effectively cooled.

Another object of the present invention is to position the low resistance tubes in a transverse row at the air entrance or front side of the device and arrange the'by-pass valve so when the oil will not pass through the high resistance tubes, it will raise the valve and be permittedto pass through these low resistance tubes.

A further object of the present invention is to provide means whereby the oil will be permitted to heat quickly because of the limited number of tubes through which it first passes and the limited cooling area exposed to the air but to percontact with the high resistancetubes and their portions of the fins.

A still further object of the present invention is to provide a device for the purpose which will be unitary, compact, light, neat in appearance and durable which can be manufactured at low cost.

Another object of the present invention is to provide an aperture in the valve partition whereby a predetermined volume of oil will be permitted to pass from the high resistance end of the header to the low resistance end of the header when the valve is closed; thus .to utilize the low resistance tubes and their portion of the fins to cooperate with the high resistance tubes in normally cooling the oil.

To these and other useful ends, my invention consists of parts, combinations of parts, or their equivalents and mode of operation, as hereinafter set forth and claimed and shown'in'th accompanying drawing in which:

Fig. 1 is a front view of my improved oil cooling device. a

Fig. 2 is a transverse sectional view of the device shown in Figure 1, taken on line 2-2 of this figure.

Fig. 3 is an end view of one of the high resistance tubes and the agitating means therein,

Fig. 4 is a longitudinal section through a fraction of one of the high resistance tubes, illustrating the agitating means therein.

Fig. 5 is a view of the agitating means before the body is zig-zagged as shown in Figure 4.

Fig. 6 is a sectional view of a modification taken on line 5-6 of Figure 7. a

Fig. 7 is a longitudinal sectional'v'iew of th modification shown in Figure 6.

As thus illustrated, my improved device co prises a lower header l0 and an upper header! i, the lower header being conventional and the upper header being equipped with a partition i2 arranged between the low resistance row of tubes and the high resistance bank of tubes.

Partition I2 is shaped as shown and provided with preferably a forwardly curved projection lz having an aperture l2 and an opening l3 formed with a seat as at I5 for a valve Hi, the valve having a stem l6 which is slidably mounted in a cap IT. as illustrated, the cap being screw threaded into an extension chamber l8 which is concentric with opening l3 and registering with member 82 I provide a spring is for holding the valve on its seat against a predetermined pressure.

mit the heated air to then come in heat exchange The headers are operatively connected together by means of preferably a front row of circular in cross section tubes 20 and a number of rows of circular in cross section tubes 2|.

Tubes 20 and 2i are provided with a multiplicity of closely spaced fins 22 through which the tubes extend and to which they are bonded in the usual manner. In designs of the class, it is customary to either form the header with separate tube plates which are removably secured to the header caps or the outer surface of the headers are provided with threaded apertures which register with the tubes for the reception of the expanding tool with which to expand the tube ends into the headers after which the apertures are closed preferably by means of pipe plugs. These methods are too well known to require further description or to require illustration in the present drawing.

Tubes 2i are provided with agitating strips which in their entireties are designated by reference character A. I have shown the preferred form of strip although many other well known designs may be used. Strips A are first formed from flat stock, as illustrated in Figure and then they are bent into the shape shown in Figure 4, the strips comprising connecting members 23 and spaced cross members 24 each having an opening 25, the ends of which are out free forming strips 26, the strips being bent outwardly as illustrated in Figure 4 so as to practically prevent a straight through path in the tubes.

When the strips are designed and bent as illustrated in Figure 4, very small straight through

openings

21 and 28 are provided but these openings are not very effective for the passage of oil because the oil is diverted violently back and forth by

members

23, 24 and 26, the oil being caused to violently impinge the walls of the tubes thus to increase the heat transfer capacity of the tubes and provide means whereby when the oil is quite thick or viscous, it will not readily pass through the tubes.

Clearly the resistance offered to the passage of chilled oil through tubes 2| may be sufilcient to cause a pressure which will lift valve ll so the oil will practically all pass through tubes 20 and since these tubes have a limited heat exchange area in contact with the blast of moving air through the core, as indicated by single pointed arrows, the oil will be permitted to heat quickly after which heat transfer will take place from the heated oil and heated air into the oil in tubes 2|. Thus the chilled stagnant oil in tubes 2| will be heated so in time valve II will be permitted to close and all of the oil forced through tubes 2| after which it, will be adequately cooled by the air blast and its contact with the fins and tubes.

In the present design, the headers form the upper and lower retainers of an air duct. I provide plates 3H0 which are secured to the ends of the headers having narrow flanges 3| which embrace the front and rear sides of the headers and protect the corners of the fins. ''hetse plates form the side members of the air In Figure 2 I have illustrated the direction of oil flow when the valve is closed by double pointed arrows.

It is generally the custom to force the blast of air between the fins and tubes by means of irontal pressure. It will be understood that my device may be used for cooling the oil on stationary engines by simply providing the device with an air moving fan similar to automobile radiators.

In Figures 6 and 7 I illustrate tubes 35 which are flattened and having therein an agitating strip comprising transverse members 36 having openings 31 therein and being connected together by means of connecting members 38, the strips being zig-zagged somewhat similar to that shown in Figure 4. This design of tube may be used in place of tubes 2| in Figure 2 and they may also be supplied as a substitute for tubes 2| wherein no agitating strips would be needed.

Aperture l2 permits some oil to pass through tubes 20 when valve I4 is closed. Thus when the valve is closed and the oil is hot, some of it will pass through tubes 20 and be cooled thereby.

Clearly many minor detail changes may be made in the present invention without departing from the spirit and scope of this invention as recited in the appended claims.

Having thus shown and described my invention, I claim:

1. A unitary oil temperature controlling device comprising spaced headers having inlet and outlet connections in their rear sides and being operatively connected together by a number of rows of tubes, a multiplicity of closely spaced strip fins through which said tubes extend, whereby a blast of air may be forced between said tubes and fins from the front thereof, at least one front row of tubes being adapted to offer little resistance to the flow of oil when chilled, the other tubes being adapted to offer great resistance to the flow of oil when chilled, a partition in one of said headers separating the low from the high resistance tubes and having a relief valve adapted to permit the oil to pass through the low resistance tubes when it cannot pass through the high resistance tubes, said rear bank of tubes having therein agitators adapted to prevent a free flow of oil therethrough.

2. A unitary oil temperature controlling device comprising two spaced headers having inlet and outlet connections in their rear sides and being operatively connected together by a number of rows of tubes, a multiplicity of closely spaced strip fins through which all of said tubes extend and in metallic contact therewith, whereby a blast of air may be forced between said tubes and fins from the front of the device toward the rear thereof, at least one row of tubes positioned at the front of the device being adapted to offer little resistance to the fiow of oil when chilled, the other tubes being adapted to offer great resistance to the fiow of oil when chilled, a partition in one of said headers separating the low from the high resistance tubes, a by-pass valve adapted to permit the oil to pass from the high resistance to the low resistance side of said partition when it cannot pass freely through the high resistance tubes.

3. A device as recited in claim 2 including: a relatively small permanently opened aperture adapted to permit free passage of oil directly from the high pressure to the low pressure side of the partition.

HOWARD F. BRINEN.