US2467992A

US2467992A - Cooling means for engine cylinders

Info

Publication number: US2467992A
Application number: US609203A
Authority: US
Inventors: Jr James C Riple
Original assignee: Avco Manufacturing Corp
Current assignee: Avco Manufacturing Corp
Priority date: 1945-08-06
Filing date: 1945-08-06
Publication date: 1949-04-19
Anticipated expiration: 1966-04-19

Description

April 19, 1949 Filed Aug. 6, 1945 J. C. RIFLE, JR

COOLING MEANS FOR ENGINE CYLINDERS 2 Sheets-Sheet l five/2257 $17265 C J? COOLING MEANS FOR ENGINE CYLINDERS Filed Aug. 6, 1945- 4 ,2 Sheets-Sheet 2 Patented Apr. 19, 1949 COOLING MEANS FOR ENGINE CYLINDERS James C. Riple, Jr., Milwaukee, Wis., assignor to Avco Manufacturing Corporation, a corporation of Delaware Application August 6, 1945, Serial No. 609,203

Claims.

The invention relates to air cooled combustion engines.

in air cooled engines in which the cylinders are arranged in rows or lines, it is desirable to maintain the cylinders in closely spaced relation and to provide cooling-means which does not require an increase of the interspacing between the cylinders. It is also desirable to adequately cool the cylinder-heads in which the combustion chambers are formed as well as the cylinder barrels.

One object of the invention is to provide bafiies which coact with the fins of different areas on the cylinder-barrels and cylinder-heads for efiicient heat transfer from the cylinder-heads which are subjected to greater heat than the cylinders.

- Another object of the invention is to provide improved baffles which form ducts and fiues for efllciently cooling the cylinder-heads and the cylinder-barrels.

Other objects of the invention will appear from the detailed description.

The invention consists in the several features hereinafter set .forth and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a side elevation of a pair of cylinders and their baflles viewed from the intake side for air and embodying the invention, parts being shown in section.

Fig. 2 is a perspective view of a pair of baffles for one cylinder.

Fig. 3 is a side elevation of a cylinder and its bafiles Viewed from the outflow side for air.

Fig. 4 is a side elevation of a pair of bafiles provided with means for clamping them around a cylinder.

Fig. 5 is a section taken on line 5-5 of Fig. 1.

Fig. 6 is a section taken on line 66 of Fig. 1.

The invention is exemplified with a pair of cylinders, generally designated 10, of an internal combustion engine. The cylinders are arranged in line and it is to be understood that the invention is applicable to engines with any desirable number of cylinders. Each cylinder comprises a barrel II in which a piston operates and a cylinder-head H on the end of the cylinder and in which the usual combustion chamber is formed. The inlet and exhaust valves are mounted in the cylinder-head outwardly of the combustion chamber. A cap I6 is secured to the outer end of head I 4 and usually encloses the valve-operating mechanism,'as well understood in the art. The barrel II is provided. with continuously annular circumferential fins I! for conducting the heat from the barrel, and which are usually formed by cutting continuous grooves in its outer periphery and are relatively thin in cross-section. The head i4 is provided with circumferential fins [5, which are of non-symmetrical contour and are usually integrally cast with the head, and for efficiency are required to conduct more heat from the head produced by the combustion of fuel in the head adjacent the valves.

The invention includes a pair of complemental bafiles, generally designated 20, and disposed on diametrically opposite sides of each cylinder, and which are spaced apart to form an inlet passage a for air, and an outlet passage b. The baffles for each cylinder are separated and adapted to form, with the fins i2 on the barrel I l, transverse passages for directing air from the side at which air fiows to the cylinder around the barrel to the outlet side, to form, with fins I5 on head [4,

transverse passages for directing air from the.

inlet side around head M to the outlet side, and ducts or fiues for conducting air from areas around the outside of the baffle-members extending around the fins l2 on the barrel H, longitudinally of the cylinders to supplementally cool the fins I5 on the cylinder-head l4. The baffles for each cylinder are of similar construction, disposed on opposite sides thereof and their ends are spaced apart to form the longitudinally extendin inlet-passage a for air at one side of the cylinder and a longitudinally extendin diametrically opposite passage b for the outflow of air. These passages extend longitudinally of the cylinder for the flow of air toall portions to be cooled.

Each baffle comprises a substantially fiat sidewall 22 which is adapted to fit between contiguous sides of a pair of in-line cylinders and extends substantially the length of the cylinderbarrel II and head I4. Each bafile also comprises an inner arcuate wall 25 which extends longitudinally along the fins l2 on barrel H and around a side-portion of the cylinder-barrel and conforms to the outer periphery of fins l2, for directing air circumferentially between said fins from the inlet passage a to the outlet passage b between the bafiies. Each wall 25 substantially contacts the fins l2 to direct the air between said fins. Each arcuate wall 25 terminates in a bead 26 at the inlet passage a and is joined at its opposite end at the outlet passage b to a vertical wall 21.

The arcuate wardly from the side-wall 22 of the same baffle wall 25 of each baflie is spaced in-.

and a bottom-wall 29 extends between walls 22, and 21 to form a transverse duct 28 which has an open end at the side of the cylinder and at one side of the inlet passage a. Each duct 28 receives air from said open end and conducts it around the arcuate wall 25 to the end of the duct 28 at the side of the cylinder where the outlet passage b is located. The end-wall 2i and sidewall 22 of each bafiie are extended longitudinally of the cylinder to a top-end wall 30 which extends across the corner of said walls 22, 2'5 to form a flue 3! which receives air from duct 28. Topend wall 3!] extends between the fins IS on head 14, which are disposed at the outer end of the zone of said head, which is subjected to the greatest heat, to extend flue 3| for additional cooling of the portion of the head Hi which is subjected to the greatest heat. Air which flows through ducts 28 to fiues SI is confined longitudinally by the corner formed by end-wall 2i" and side-wall 22 so it will flow into the spaces between the fins E5 on head i l and escape therefrom through the outlet passage 22. A, curved flange 32 on each end-wall 2? is designed to provide the proper exit passageway for the air emerging from the grooves between fins it, thereby providing for maximum air flow at a given pressure differential.

Each side-wall 22 is secured by a screw 23 to the outer end of the cylinder. If desired, tie bolts 35 between lugs 34 secured on walls 38 of the baiiles may be used to secure baffles around the cylinder.

The operation is as follows: air flows through the inlet passage a between the bafiies to fins E2 on barrel ii and then circumferentially around opposite sides of the barrel on the inner side of arcuate walls 25, through the grooves between said fins to the outlet passage b between the baffles. This air cools the barrel. Air also flows from inlet passage a between the side-walls 22 and cylinder-head Hi to fins IE on head it and around and between said fins to the outlet passage 1) between the bafiies. Streams of air also pass into the transverse ducts 28 formed by arcuate walls 25, side-walls 22, bottom wall 29 and end-wall 2? into the fiues 3! which communicate with the fins IE on head It and the grooves between said fins. The flues 3! extend longitudinally of the fins it: on that portion of head I which is subjected to the greatest heat from the combustion chambers in the cylinders and terminate at the outer-most fin on said portion of the head. The streams of air passing into flues 3| flow through the spaces between fins 5 to the outlet passage 1). In this manner, the ducts 28 and lines 3| supplement the cooling of the portion of head M which is subjected to greatest heat for efficient cooling. The flanges 32 provide for the maximum fiow of air air emerging from the fiues 3|.

The construction described results in high efficiency in the transfer of heat units from head i i and barrel ii of the cylinder, is simple, and fully utilizes the interspace between adjacent cylinders so that it is not necessary to provide an increase of space between the cylinders for the accommodation of the baliies. The batlles are supported entirely from the cylinders, and may be readily applied thereto.

The invention is not to be understood as limited to the details described, since these may be modified within the scope of theappended claims without departing from the. spirit and scope of theinvention.

Having thus" described the invention, what I claim as new and desire to secure by Letters Patent is:

1. Cooling means for an air-cooled engine having a cylinder including a cylinder-barrel provided with a series of circumferential fins, and a cylinder-head provided with a series of circumferential fins, comprising: a pair of diametrically opposite complemental bafiies having between "rem longitudinal and diametrically opposite inlet and outflow passages for air and extending longitudinally for the flow of air transversely to and from both series of fins; each baffle including an outer side-wall extending longitudinally along the barrel and the head, an inner wall extending circumferentially around a portion of and longitudinally along the barrel, for directing an inner stream of air from the inlet passage around the fins on the barrel to the outlet passage, the outer wall being spaced from the inner wall, for directlng air transversely around the inner wall from the inlet passage, and a structure adjacent the outlet passage forming a flue extending longitudinally along the cylinder head which opens to the air on the outer side of the inner wall and for conducting said last named air to fins on the head and thence to the outlet passage;

2. Coolin means for an air-cooled engine hava cylinder including a cylinder-barrel provided with a series of circumferential fins, anda cylinder-head provided with a series of circumferential fins, comprising: a pair of diametrically opposite complemental baiiles having between them longitudinal and diametrically opposite inlet and outfiow passages for air and extending longitudinally for the flow of air transversely to and from both series of fins; each baille including an outer side-wall extending longitudinallyalong the barrel and the head, an arcuate inner wall extending circumferentially around a portion of and longitudinally along the barrel, for directing an inner stream of air from the inlet passage, around the fins on the barrel to the outlet passage, the outer wall being spaced from the inner wall, for directing air transversely around the.

inner wall from the inlet passage, and a structure adjacent the outlet passage forming a flue extending, longitudinally along the cylinder head, which opens to the air on the outer side of the inner wall and for conducting said last named air to fins on the head and thence to the outlet assage.

3. Cooling means for an air-cooled engine having a cylinder including a cylinder-barrel provided with a series of circumferential fins, and a cylinder-head provided with a series of circumferential fins, comprising: a pair of diametrically. opposite complemental baflies having between.

them longitudinal and diametrically oppositeinlet and outflow passages for air and extending longitudinally for the flow of air transversely" to and from both series of fins; each baffle including a substantially straight outer side-wall extending longitudinally along the'barrel and the head; an arcuate inner wall extending circumferentially-* around a portion of and longitudinally along the. barrel, for directing an inner stream of 'air'from: the inlet passage, around the'fins on the barrelt'o: the outlet passage, the outer wall being spaced from the inner wall for directing air transversely around the inner wall from the inlet passage, and a structure adjacent the outlet passage forming-e;- flue extending longitudinally along the cylinder" head, which opens to the air on the-'outer-si'de-off the inner'wall, and for conducting air tosaid' last named fins on the head and thence to the outlet passage.

4. Cooling means for an air-cooled engine havin a cylinder including a cylinder-barrel provided with a series of circumferential fins, and a cylinder-head provided with a series of circumferential fins, comprising: a pair of diametrically opposite complemental baflles having between them longitudinal and diametrically opposite inlet and outflow passages for air and extending longitudinally for the flow of air transversely to and from both series of fins; each bafile including an outer side-wall extending longitudinally along the barrel and the head, an inner wall extending circumferentially around a portion of and longitudinally along the barrel, for directing an inner stream of air from the inlet passage around the fins on the barrel to the outlet passage, the outer wall being spaced from the inner wall for directing air transversely around the inner wall from the inlet passage to the outlet passage, and a structure adjacent the outlet passage at one corner 01 the cylinder, forming a flue extending longitudinally along the cylinder head, which opens to the air on the outer side of the inner wall, and for conducting air to said last named air fins on the head and thence to the outlet passage.

5. Cooling means for an air-cooled engine having a cylinder, including a cylinder barrel provided with a series of circumferential fins, and a cylinder head provided with a series of circumferential fins of greater diameter than the fins on the barrel, comprising: a pair of diametrically opposite complemental baflles having between them longitudinal and diametrically opposite inlet and outflow passages for air extending for the flow of air transversely to and from both series of fins; each bafile including an outer side-wall extending longitudinally along the barrel and the head, an inner wall extending circumferentially around a portion of and longitudinally along the barrel, for directing an inner stream of air from the inlet passage around the fins on the barrel to the outlet passage, the outer wall being spaced from the inner wall for directing air transversely around the inner wall from the inlet passage, the inner wall extending to the inner fin on the head, for separating the air flowing around the fins on the barrel from the air on the outer side of the inner wall, and a structure adjacent the outlet passage, forming a flue extending longitudinally of the cylinder head, which opens to the air on the outer side of the inner Wall, for conducting ale to fins on the head and thence to the outlet passage.

JAMES C. RIPLE, J R.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS