US2477061A - Radial engine - Google Patents

Description

July 26, 1949. 0, E. |RV|NG 2,477,061

' RADIAL ENGINE Filed May 11, 1943 2 Sheet's-Sheet 1 2. 2re y,

July 26, 1949. o. E. lRvlNG 2,477,061

' RADIAL ENGINE Filed may 11, 1945 2 sheets-sheet 2 INVENToR. ORv/LLE E /RVl/VG.

Patented July 26, 1949 UNITED STATES PATENT OFFICE RADIAL ENGINE Orville E. Irving, San Francisco, Calif.

Application May 11, 1943, Serial No. 486,511

2 Claims. 1

This invention relates to radial engines and has for one of its objects the provision of an improved internal combustion radial engine that is adapted to produce more horse power per pound of weight than conventional radial engines heretofore made, and which engine is of relatively simple construction and utilizes many elements common to conventional radial engines.

Another object of the invention is the provision of an internal combustion four-cycle radial engine having an even number of cylinders that are adapted to be fired twice for each complete revolution of the drive shaft to which the power from the pistons during their power strokes is directly transmitted.

In most static four-cycle radial engines heretofore made an odd number of cylinders has been employed, such as nine, and the fuel has been ignited in every second cylinder around the engine as it rotates. Thus all cylinders' have been fired once during each two complete revolutions of the engine. With my engine an even number of cylinders is used and all cylinders are iired twice during each complete revolution of the engine, and the firing of the cylinders is in pairs instead of singly, the iiring pair being preferably axially aligned and at opposite sides of the drive lshaft to which they transmit their power on the power stroke. Thus my structure provides an engine that is balanced with`respect to torque forces developed during the power strokes of each pair of pistons in the firing cylinders, while the structure also makes possible greater horse power per pound of weight.

Other structure hereinafter described more in detail will show other objects and advantages of the invention.

In the drawings,

Fig. 1 is a semi-diagrammatic view of .an engine, part in section and part in elevation.

Fig. 2 is a fragmentary sectional view through one cylinder of the engine of Fig. 1 as seen from line 2-2 of Fig. 1.

Fig. 3 is a diagrammatic view of the central cam in one of the positions during driving thereof by the pistons.

It will clarify the description to explain that many of the elements of my engine are conventional or substantially so, such as the cylinder barrels, cylinder heads, poppet valves and valve actuating mechanism, crank case, and manner of mounting the ycylinders on the crank case. Also, the crank case may be of the type that has a nose section, power sections (carrying cylinders), mounting section (for securing.. to .usual engine 2 mounting ring), and super-charger, pumps, tachometer, gun synchronizers, eta). These various sections are well known in the art and are not all indicated in Fig. 2, it being understod that no claim is being made to any of such sections in themselves.

Eight equally spaced cylinders are indicated in Fig, 1 and are numbered I to 8, inclusive, cylinder I being the uppermost, and the others being numerically in order from 2 to 8 in a Iclockwise direction as seen in Fig. 1. The conventional cooling iins are not shown on the cyllnders for the sake of clarity in the drawings.

Each cylinder has a conventional head with the usual poppet valves 9, l0 therein, the valve 9 being the intake valve, and valve I0 beingthe exhaust valve.

Pistons I I to I8 are respectively in the cylinders I to 8, each piston having the conventional sealing rings thereon, and each being formed with bosses I9 (Fig. 2) in which a wrist pin i20 is supported. In the drawings an inner race 2| is supported on the wrist pin 20 centrally thereof, and roller bearings 22 rotatably support an outer annular race 23 thereon concentric with the axis of pin 20. The rollers 22 may be centrally grooved and inner race 2| may be formed with an annular ridge extending into the grooves in said rollers as seen in Fig. 2, if desired.

A central drive shaft 25 carries the main cam 26, the hub `28 of the latter being splined to the shaft as at 21.

Where the engine is used in an aircraft, the one end "29 of the shaft 25 may be the propeller shaft, unless it is found desirable to provide a gear connection between the propeller and shaft 29, while the other end 30 of shaft 25 may be for driving accessories such as a super-charger, pumps, etc., not shown.

For an eight cylinder engine, as shown in the drawing, the central cam is formed with four equally spaced lobes 3|, 32, 33, 34 (Figs. 1, 3), the peripheral outline of the cam being convexly curved at the outer ends of the lobes and concavely curved at the low points 35 between adjacent pairs of lobes. The lobes are identi-cal with each other in size Vand contour and the cam is symmetrical at opposite sides of a plane bisecting it through lobes extending oppositely from each other relative to the axis of the central shaft 25.

The cylinders I to 8 may be secured in the usual manner to a, conventional crank case 36 by means of bolts extending through mounting flanges 31 on said cylinders, and which crank 3 Y case is provided with the usual bearings rotatably supporting shaft 25 (Fig. 2). Y

The cam 26 is supported on shaft 25 in a position so that the outer race 23 in each of the pistons will roll onv the peripheral surface of the v cam. As each of the said races 23 is Virtually a roller, the term roller will be used hereafter to designate the said races.

eighthrof a revolution of cam 26 will complete the exhaust stroke ofl piston II and the Ynext eighth of Va revolution will complete the intake I stroke. After the intake stroke, the next eighth The rollers 23 are held in engagement with the'V peripheral vsurface ofthe cam 26 at all times by means of a pair of arms extending divergently from the Wrist pin in each cylinder to the wrist through its power, exhaust, intake and comprespins of a pair of other cylinders. For example,in

the eight cylinder engine of Fig. 1 there are, all told, eight arms. From the wrist pin of piston I I, a pair of arms 40 extend to the wrist pins of piston I4, I6, the latter being in the cylinders at opposite sides of the cylinder thatvr is opposite cylinder I. From the piston I2 a pair of arms-'4I extend divergently to the pistons I5, Il and from piston I3 arms 42 extend divergently to pistons I6, I8. As one end of arm 46 connects piston I I with piston I 4, a second arm 43 connects piston I4 with piston I1. Piston I5 is connected .with'piston `I2 by one c-f the arms 4|, therefore a second arm d4 connects piston I5 withA piston I6. By this ar-V rangement each piston is connected with those pistons oi the pair that are at opposite sides of the piston directly opposite thereto. i

rEhe peripheral contour of the cam 2.6 is such 1 that the arms connecting the pistons willihold all the rollers 23 against the said contouix-and whenv any one roller 23'` is positioned at the outer end oi one. ofthe cam lobes, the rollers inthe pistons directly connected thereto by a pair of the arms abovedescribed will be positioned at the low points onthe cam at the opposite sides of the lobe directly opposite. the one over which the roller is passing.

The compression, power, exhaust and intake strokes of theV pistons arecontrolled by the actuation 'of the valves, ignition, etc., in the usual manner. g

' The intake. andA exhaust valves S, I@ are, each held closed by a valve spring 5i). To eachzvalve is a rocker arm 5I Vcarrying a roller 52 at one end for actuating 'the valve.A The oppositeend of the rocker arm is connected by a push rod- 53 with a tappet 54 tl'iatcarries a. roller 55. A51 carried by shaft 2.5 actuate the tappetsrfor 'actuation o f the intake and exhaust valves yin proper order and timing. Spark plugs' 58 inthe cylinder heads are actuated in the conyentional manner for ring the cylinders. All these Vele-- ments are conventional, although the cams 56,'

51- are designed for opening and closing the valves in the eight cylinder engine herein illustrated, instead of being `for the ordinary nine cylinder engine. Y

In Fig. 3, the rollers 23 represent thoseindicated in Fig. 1 and the pistons to which they are connected are indicated thereon. Also'on each roller is indicated its stroke; for example, PV

means power stroke, Ex means exhaust stroke, I means intake stroke,V and "C means compression stroke. The central cam 261m Figj 3 has rotated clockwise one sixteenth of arevolution from the position in Fig. 1. 'I'his view being understood, the actual operation ofthe engine through the four cycles'of piston Il may readily be followed. A one-eighth revolution of cam g-lockwise from the position of the cam in Fig, 1 will complete theA power stroke of said piston,` or another sixteenth of such revolution of the cam Fig., 3:'wil1complete' such stroke- Cams 55,

Another sion strokes simultaneously with piston I I. When thel cylinder I (carrying piston II) is iired, the cylinder EiV (carrying piston I5) is also red. Thus these pistons move toward and away iromeach other simultaneously. It will be observed that the movement ofY piston II in its power stroke will cause outward movement of pistons I4, I6, the former being on its4 compression stroke'and the latter on` its exhaust; stroke;V while the. movement of piston I-5- in its power stroke causes.V outward movementot pistons; |18', 4 I2;v the former being on itsV compressionl stroke (fand diametrically oppo-V site' piston I4) whirlethe latter;willbe on its exhaust stroke (andi 'diametrically' opposite piston l5); This movement of pistons I4,` It by piston II is by reason: tif-'arms 4.6.' thatvr connect them. together with the power'i transmitted' through lobes 32, 33 of cam 12B", while thernovement of pistons-1:2, I6 isby-reason or arms 41,44, together with the power transm'lttedfthrough lobes-,351,- 3Q ofthe camj" u The remaining' twodiametrically opposite pistons I3, I1 areY respectively connectedtopistons l, i3 "(by' arms'flg, and |`2","l4 '(iby" armsitl, 43)

and. which VY pistons ISLA* H wardlyon inta-ke strokes'by reason of vtheV outiward-movement-'of'pistons I6, I 8 and' I2, I4. VEach' diametrically'oppositelpair `of cylinders is fired twice duringeaoh complete' revolutionoixtlie cam Y '26, and these, diametrically oppositepairs 'oiy pisf tons always have the; same stroke. *"Ihe. iring order of the cylinders of. theparticular engine inustrated irl Figs, 1,3 ijs-lil, 15j- 1.4, Isala, u g

Ycylinders are valways and I2, I 6.' lIwo opposite red simultaneously.

The shape oi cam 26, maybe slightlyv modified according .td thediameter. oi fthe rollers. 23, and ,desired stroke. of the pistonsA In1Figs.1 and 2v it will `be seen that. thelcylinders Yare slottedat @t topas's the cam lobes. The lpistons..t'henlselves are formed with brace andezude. members, as, at

6I (Fig. 2.)` and oneo' the, arms 4.6, 4I, 42, and

arms/,43 are. atene'. side/of the cam' 2.6, while the other of arms 49', 4h42 and arm lili are at the opposite side of said cam. ,'lhis'arrangement could be modified to provide, for Vpositioning all of the arms between apai-r` or spaced cam-s similar to cam 26, andfby providing a `pairof rollers in eachrpiston, `but it is, intended that such Amodi-.- cation shall come within the scope'of; the claims.

In Fig. 3 it will ble-seenY that as soon as the Vrollers 23- pass theouter; endso'fthe lobes ofthe cam on the power strokes of the pistons-the initial radially inward movement of the rollers delivers the maximum power tothe' cam, which power progressively Vbeson-res'less until the rollers are at the'rlow points4 between lobes. Thus' the timing of the firing Vis such as to take advantage of the full power of the powerstrokeslwhere there is the 'maximumvefciency in-transferfthereof to thecam.V f

The invention hereifnbefore described is iintended as illustrative of the invention and not restrictive thereof.

Having described my invention, I claim:

l. In a radial internal combustion engine having a rotatable central shaft, an even number of not less than eight equally spaced stationary eyh inders radially positioned around said shaft, a piton reciprocable within each cylinder, a cam fol lower carried by each piston and recprocable therewith, a cam on said shaft having radially extending equally spaced similar lobes equal to one-half the number of said cylinders, said cani followers being in engagement with the cam surfaces of said cam, the improvement that coinprises; a pair of arms extending divergently from each piston and past opposite sides of said shaft connecting each piston with a pair of diierent pistons that are equally spaced therefrom by intervening pistons and cylinders and which latter pair are spaced from each other by a single intervening piston and cylinder only.

2. In a radial internal combustion engine ha"m ing a rotatable central shaft, an even number of not less than eight equally spaced stationary cylinders radially positioned around said shaft, a piston reciprocable Within each cylinder, a cam follower carried by each piston and reciprocable therewith, a cam on said shaft having radially extending equally spaced similar lobes equal to one-half the number of said cylinders, said cam REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date Re. 16,630 Nordwick May 24, 1927 717,445 Nestius Dec. 30, 1902 1,594,045 C'amnez July 27, 1926 1,597,474 Nordwick et al Aug. 24, 1926 1,817,375 Imblum Aug. 4, 1931 1,830,046 White Nov. 3, 193i FOREIGN PATENTS Number Country Date 12,337 Great Britain 1909 706,391 France June 23, 1931

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