US1670666A - Air-cooling means for internal-combustion engines - Google Patents

Description

May 22, 1928.

A. G. M. MICHELL AIR COOLING MEANS FOR INTERNAL COMBUSTION ENGINES Filed Sent. 20. 1927 2 Sheets-Sheet l May 22, 192s. 1,670,666

A. G. M. MICHELL AIR COOLING MEANS FOR INTERNAL COMBUSTION ENGINES Filed Sept. 20.l 1927 2 Sheets-Sheet 2 Patented May 22, 1928.

UNITED STATES PATENT OFFICE.

ANTHONY GEORGE MALDON MICHELL, OF MELBOURNE, VICTORIA, AUSTRALIA., AS- l SIGNOR To cRANKLEss ENGINES LIMITED, E MELBOURNE, AUSTRALIA.

.AIR-COOLING MEANS FOR INTERNAL-COMBUSTION ENGINES.

Application filed September 20, 1927, Serial No. 220,762, and in Great Britain July 27, 1926.

The object of the present invention is the provision .of more effective and efficient alroooling means for the cylinders of internal f combustion engines of the type in which the result of its own passage through the air when mounted in a flying-machine or other vehicle, but the invention is also in part ap plicable to stationary engines.

It is in many cases desirable to arrange the working cylinders of crankless engines at the rear as well as the front of the main case of the engine, or sometimes at the rear only. It is to the cooling of such rear cylinders that the present invention, which consists in improved cooling apparatus, Yis particularly directed.

According to the present invention, the air meeting the front (or Windward end) of the engine and being thereby deflected outwardly is intercepted by an annular series of baf fles 0r a collector plate of such shape and arrangement that parallel' air streams are formed, such parallel streams being subsequently intercepted by an annular series of baffles at the leeward end of the engine and of such shape and arrangement that the parallel air streams are diverted inwardly upon and over the vrear cylinders. The baffles may be arranged in stepped annular formation. The baflle or collector plate may be of annular or cylindrical shape, its` rear being apertured centrally. A fan may be provided at or near the exit. from said collector or baffle plate.

In theaccompanying drawings, the inven* tion is shown in. Figs. 1 to 3, 5, 7 and 8, as

applied to engines of flying machines; Figs.'

1 to 3 and 5 being diagrammatic, while Figs. 7 and 8 are longitudinal and end views re! spectively of a practical form of construction of an' engine and the -cooling device as shown diagrammatically, in Fig. 2. Fig. 4 is a diagrammatic view showing the application of the invention to a stationary engine. Fig. 6 is a diagrammatic view of a. crankless engine for flying machines without the cooling device.

In each of the Figures 1, 2, '3, 5 and 6, the engine shown by way of illustration, is a crankless engine a'daptedto be propelled together with its support, through the air by means of a propeller P mounted at the front of the engine.

Figures 1, 3, 5 and 6 represent single-end ed engines, that is to say engines having their working cylinders C mounted only on the rear ends of their castings or bodies B.

For convenience of explanation of the improved cooling apparatus the engine will be regarded as at rest, as is the case of theV crankless engine in Figure 4, and the air as moving in the direction shown by the arrows a and so that the air has thus the same motion relative to the engine as if the latter were travelling forward in still air.

In an engine unprovided with the cooling apparatus which forms the subject of the present invention, air streams meeting the front or Windward end ofthe body B tend to be deflected laterally away from the engine, as indicated in Figure 6, and `to diverge more and more as they progress to- Wards the rear, as shown at a', a, in that figure. The air surrounding the cylinders C is in consequence either stagnant, or, at the most, disturbed only by secondary eddies e eas indicated in Figure 6, and. has consequently little cooling effect.

According 'to the present invention, and as shown in Figures 1, 2, 3, 4 and 7, air is intercepted by an angular' series of baffles L1 arranged around the front circumference of the body B. Alternatively, a cylindrical baf-l lie or collector K may be provided for the same purpose yas shown in Figure 5.

The baffles are of stream-line forms and are designed to deflect the air with as little loss of energy as possible into paths 7) b approximately parallel to the axis of the yengine, a second annular series of baffles lL2 is arranged, these being located so as to deflect the airstreams b I) inwardly over and between 'the cylinders and designed, like the bafHes L1, to deflect the air with the least possible loss of energy.

In the double-ended engine shown in Figure 2, in which cylinders C1 are mounted at the front end as well as the cylinders C2 at the rear end of the engine body B, the air streams aa are deflected outwards partly by the front cylinders, which they serve to cool, and partly by the front of the body B, as in the arrangement illustrated in Figure 1.

The series of front bafflesL1 is therefore distributed over a greater axial distance than in Figure 1 so as to intercept as far as possible ,y the variousl streams diverging from both the body B and the cylinders C1. In other respects the construction and effects in the arrangement of Figure 2 are similar to those of Figure 1. In both the single and double-ended constructions, annularl or sectional baffles F may be added, continued by cylindrical extensions outside the leeward louvres, as indicated in Figs. 2 and 7, to intercept additional air and/or to concentrate the flow of air about the cylinder heads.

The construction shown in Figure 3 is precisely the same as that of Figure 1, except that a fan G isfmountcd at the rear end of the engine, upon, or co-axially'with, and driven by the engine shaft so as to receive the airstream issuing from between the cylinders, and by its propelling or tractive action upon the air, increase the fiow and cooling effect of the current. In order to prevent air from being drawn directly into the inlet of the fan G without passing over and cooling the cylinders C an annular baie H may be fitted,

thisbafile beingalso continued outside the leeward louvres, as shown.

A practical mode of construction' of the baffles above described and their attachment to the engine, is illustrated in Figs. 7 and 8. According to these figures the baffles L1 and L2 are continuous rings, of stream like section, preferably of a light alloy, smoothly machined, arranged concentrically and attached to one another and to the-engine by oblique radial bracket-arms M,L M2.

The annular baffle F, is preferably spun from sheet metal and being concentric ywith the baffles L2 may also be attached withv them to the engine by the arms M2.

In the double-ended engine representedin Figure ,4, and operating as a stationary engine, the fan G alone produces the propelling effect upon the cooling-air. In order to prevent the fan from drawing. air directly into its inlet Without such air passing between the bafiies L1 and L2 and over the cylinders, the bailcs are surrounded by a cylindrical baiiie or collector J. The construction and eect of the cooling means in this case are similar to those shown in Figure 2 except for the addition ofthe fan G, and the increased length of the cylindrical portion of the baille J in 4 Figure 4 as compared with the baille F in Figure 2. It is to be understood that these modifications are also applicable to a doubleended engine when fitted with a propeller, as shown in Figure 2, and used as the engine of a flying machine.

The sets of baffles L1 and L2 are prefer-I the leeward end of the engine to intercept said parallel air streams and divert them inf wardly upon and over the rear cylinders.

2. The combinationv with an internal combustion engine, in which the working cylinders are cooled by a current of air iowing parallel to the axis of the engine, 0f a series of annular baffles arranged in stepped formation for deiecting said current of air inwardly upon and between the engine cylinders situated at the leeward end of the en-I gine.

ternal combustion cra-nkless engine, of a series of annular bales arranged around the Windward end of the engine, a series of annular bafiies arrangedvaround the leeward end of the engine, and a centrally apertured annular baffle surrounding the leeward bales.

Dated this 24th day of August, 1927. e. ANTHNY GEORGE MALDON MlCl-IILI..y

3. The combination with an air-cooled ini

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