US2445483A - Method and means of producing power - Google Patents

Description

y 1948. E. JACOBSEN 2,445,483

METHOD AND MEANS OF PRODUCING POWER Filed Sept. 24, 1945 6 Sheets-Sheet 1 INVENTOR. [ow/N Jbcaass/v 4 Adam E. JACOBSEN METHOD AND MEANS OF PRODUCING POWER July 20, 1948.

Filed Sept. 24, 1945 6 Sheets-Sheet 2 5 INVENTOR.

fbw/N ficaasz-N.

9mm $4 M July 20, 1948. E. JACOBSEN 2,445,433

METHOD AND MEANS OF PRODUCING POWER Filed Sept. 24, 1945 6 Sheets-Sheet 3 5 JNVENTOR. v .fbw/N .Zcamstfl y 1948- E. JACOBSEN METHOD AND MEANS OF PRODUCING POWER- Filed Sept. 24, 1945 r 6 Sheets-Sheet 4 INVENTOR. f ON/Y'Y Jim/z $2M? m m Irr/ July 20, 1948. JACQBSEN 2,445,483

METHOD AND MEANS OF PRODUCING POWER Filed Sept. 24, 1945 e Sheets-Sheet 6 22 (E CYLINDER. v w Q A AXIS CRANK PIN 22 Z w (E HOKI'Z. POWER. SHAFT [N V EN TOR. few/N Jirrosss/v.

Patented July 20, 1948 METHOD AND MEANS OF PRODUCING POWER Edwin Jacobson, Altadena', Calif.

Application September 24, 1945, Serial No. 618,212

Claims.

This invention relates to internal combustion engines, and particularly pertains to a method and means of producing power.

The standard type of reciprocating internal combustion engine is designed of necessity on the principle that the power stroke begins in the interval when the'crank throw of the engine pistonpasses over top dead-center. It is obvious that when combustion takes place within the cylinder with the piston on top dead center the moment of torque force around the crankshaft axis will be zero, and thus the explosive force incident to. combustion will not be converted into tangential torque force around the axis of the crankshaft. This condition results in a definite power loss aside from the fact that considerable strain and. wear is set up in the engine structure. Various attempts have been made to correct this fault in reciprocal engine design, such as is disclosed in my U. S. Letters Patent No. 2,314,789, issued to me March 23, 1943, and in my co-pending application entitled Internal combustion engines, Serial No. 527,977, filed by me in the United States Patent'Oflice March 24, 1944. In my solution of the problem, as disclosed in the aforementioned patent and application, I have provided a structure in which the piston and crank throw therefor will not be concurrently on top dead-center, but that the crank throw will be several degrees beyond its dead-center position when the piston is at its uppermost end of the stroke. Such an arrangement prevents power loss at the time the piston is at its uppermost. position and is starting its firingv stroke. This arrangement also tends to insure that a maximum proportion of the power cycle of the engine will be occupied in transmitting the explosive power into tangential force. It is desirable to provide an internal combustion engine having all of the foregoing advantages, and which insures that the crankshaftwill be so balanced as to maintain the complete cycle of engine operation in the first harmonicphase without setting up vibrations and disturbances in the second harmonic phase, thus insuring that a high power reciprocating engine will function to. produce a maximum amount of power with a minimum amount of vibration, and thus reducing the amount of stress and wear set up in the engine. It'is the principal object of the present invention, therefor, to provide an internal combustion engine of the reciprocating type where one-hundred percent or the, totalforce acting on the piston is converted to tangential force, or useful work, during the combustion portion of the power stroke, and which further insures thatany. tende. ency for the piston and crank units to. concurrently reach a zero moment will be obviated? by means which prevent a rigid and positive dead center action to occur either in the crankshaft or with relation to the reciprocating piston.

The present invention contemplates the provision of an engine having a cylinder withiir' which a piston reciprocates, which engineis pro-= means for complete balance of the reciprocating parts in the first harmonic phase, and to insurethe transmittal of maximum driving torque from the piston to the poweroutput shaft.

The invention is illustrated'by way of examplein the accompanying drawings in which:

Figure 1 is a view in side elevation'showing a complete engine with which the present invention is concerned.

Fig. 2 is an enlarged view in transverse section through the engine as seen on the line 22 'of Fig. 1 and shows the crankshaft construction and mounting, the counterbalance therefor, and'th'edriving connection with the power output shaft;

Fig; 3 is a fragmentary View in section and elevation as seen on the line 33 of Fig. Z and shows'the construction of one complete cylinder unit including the piston, crankshaft, and the crankshaft mounting.

Fig. 4 is a view in diagram showing the piston of the engine on absolute dead-center and'indieating the relationship of the crankshaft and the powerv output shaft at that instant.

Fig. 5 is a view similar to Fig. 4 showing the piston, the crankshaft, and its mounting directly after firing. This view also shows the manner in which the crankshaft support adapts itself to the initial firing impulse prior to the timezittakes for the power stroke to be transmittedito but it shows the'piston andthe crankshaft on" bottom dead-center, and thus 180 beyond its position when at top dead-center.

Fig. 8 is a graph showing the engine performance of an engine at full throttle selected for the purpose of demonstrating the present invention.

Fig. 9 is a view in diagram illustrating the relative movement of the axes of the crankshaft during one revolution of the crankshaft.

Referring more particularly to the drawing, l indicates a cylinder block which is mounted upon a crankcase H. The cylinder block carries a desired number of cylinders I2 within each of which a piston l3 reciprocates. The cylinder heads include an intake port 14 and an exhaust port IS. The intake port is here shown as connected with a carburetor and heater unit I6.- The intake gas is controlled by the usual tappet valve II actuated by a timing shaft l8 having timing cams l9 thereon. The piston I3 is provided with a connecting rod 23 pivotally attached to the piston by a wrist-pin 2| and attached to the crank-pin 22 of. a crankshaft 23. By reference to-Fig. 30f, the drawing, it will be seen that the crankshafts are individual units, one provided for each-piston. They are also mounted for individual movement both in rotation around their axesv and also when they and their axes move bodily in theplane ofthe longitudinal axis of the cylinder 13. Each ofthe crankshafts 23 have crank-arms 24 between whichthe crank-pin 22 is mounted. The crankshaft 23 is a composite shaft structure having sections 23 which are concentric with the rotating axis of the engine, and sections 23 which are eccentric to the rotating axis of the engine. The eccentric sections 23? are journaled in bearings 25 which are carried at the, upper ends of vertical oscillating arms 26. As shown in Fig. 3 of thedraw-ings the eccentric crankshaft sections 23 are formed directly with theouter faces of the crank arms 24. Thus, the crank-arms 24 and the connecting crank-pin 22 gyrate around the eccentric axesof the crank shaft sections 23 and between the vertical arms 26. The lower ends of the arms 26 are formed with bearing members which receive bearing bushings 28. Disposed at opposite ends vof the bearings 27 are supporting journals longitudinally aligned with the axes'of the bearings 23 to receive a'pivot shaft. 30, around the axis of which the vertical arms 26 oscillate, as will be hereinafter described. The journals 29 are tied together by an intermediate web'3l and are fastened by cap screvvsv 32 to the upper face of a' resilient accumulator plate 33. The accumulator plate 33 is of a width substantially agreeing with the [overall length of the pivot shaft 33. By reference to Fig. 2 it will be seen that the plate 33 is substantially rectangular, and that in a plane normal to the axis of the pivot shaft 30 its lower face tapers upwardly andv outwardly from the point of mounting of the journals 29 to the edge thereof. This point of mounting is substantially midway .betweenthe edges of the plate 33. The plate 33 has been selected to have a desired resilience so that under conditions to be hereinafter explained it will deflect downwardly under the influence of force applied from the crankshaft through the arms 26. Mounted over the outer edges of the accumulator plate 33, and which edges are parallel tothe axis of the shaft 30 are rocker bars 34. These-bars are slotted to receive an edge of the plate, after which they are secured in position by screws 35. Complementary socket clamps 36 partially embrace the rocker bars 34 and are held in position by bolts 31 which are fastened through of the axes of the concentric crankshaft section 23 and the eccentric crank section 23. As pre- 4 flanges 33 extending inwardly from the walls of the crank-case. The inner edges of the socket clamps 36 are relieved, as indicated at 39, to permit flexure of the accumulator plate 33 as the rocker bars 34 rotate On their axes. The clamping sockets 36 are braced rigidly by a transverse brace member 46 which is disposed below the clamps 36 and through which the bolts 31 extend. This brace member is formedvwith'l central openings 46' to accommodate the heads of the cap screws 32 when the accumulator plate 33 is deflected. A drain pan 4| is secured to the bottom of the crank-case and houses the previously described structure.

The individual crankshaft units are intended to drive a common output power shaft 42. This shaft is mounted in suitable bearings 43 formed within the crank-case H. The power output shaft 42 is fitted with a plurality of gears 44, one of the gears being provided for each of the crank units. In mesh with each of the gears 44 is a gear 45. The gears 45 are secured to bolting flanges formed integral with the concentric sections 23 of the crankshaft. The engine is designed to permit separate migratory movement viously explained, the eccentric crankshaft section 23 is mounted upon the upper end of vertical crank arms 26 which oscillate around the hori- Zontal axis of the shaft 30. The concentric crankshaft sections 23 of each crankshaft unit are mounted upon radius arms 48. These arms are mounted at one end upon the power output shaft 42 around the axis of which they pivot. The

free ends of these arms are mounted upon the concentric sections 23 of the crankshaft, so that as the arms 46 oscillate the crankshaft sections 23 will swing on an arc concentric with the axis of the power output shaft 42. This will insure that the gears 44 and 45 will remain in constant mesh at all times. It is intended that the axes of the crankshaft sections 23 shall travel along an arcuate path which is tangent to the vertical center of a complementary engine cylinder I2,

and that when the concentric sections 23 of a crankshaft unit are in the horizontal plane with the axis of the power output shaft 42 the engine piston 13 will be on top dead-center. At such a time the axes of the eccentric shaft sections 23 will be in substantially the same vertical plane as the axes of the concentric crankshaft sections 23. Thus, at this particular time the axis .of the pivot shaft 30 and the eccentric crankshaft sections 23 and the axes of the concentric crankshaft sections 23 of a particular unit will lie in substantially the same vertical plane as the vertical axis of a complementary engine cylinder,

while the axes of the concentric crankshaft sec These counterweights balance the rotating por-" tions of the reciprocatin parts of the connectin rods. The crankshaft mass and the arms as a whole balance the reciprocating inertia forces of the engine.

1 operation of the-' present invention it?- is understdod that the engine is constructed: and asisembled as shown: in thedraw-ings; It should be" pointedout that due to the fact that the crank shaft i's'ineffect aapluralityof-' separate units-in divid'uallt functioning while heir-re in' constant drivlhg connection with: a com mon ower output shaft-the present engine-noes not require comfo'r'manceat f-u1l throttle'isdisclosedi In the-em gine-cardshown-in Fig 8 it will-be seen that igni.-- tion takes place at approximately thirty-five-degrees from top dead-center, as indicated by the point S; and that the portion or the curve lying along the zero crank angle represents theperiod whemtheipiston l'-3- ismovingto its topdead -cen-- ter'posi tion; as indicat'edlin Fig; 4- of the drawings; It is-to be: understood that the solid line on-the chart shown in- Fig; 8; which extends upwardly froma pressure calibration of'500 to-900 and then along the'power cu'rve tioapproximately 300, represents normal engine performance;

the usuallower curve'but" from the pressure cali-- bration'offiOQ to 600- and then returning to 300'. Here it will" be seen that at a pressure of 500' pounds persquare: inch the crank turns approximately degrees; during-which time the pressure per square inch rises to 600 pounds. It maintains this" pressure until* the cza-nlr has moved" to'an angle of? the orderof 50". During this time the engine parts, are in nootionfrom dead-centerto approximately 50 while the accumulator plate" 33is deflected; as-shown'in Fig: 5 of the drawing.

It will be understo0dthat when the fuel was{ ignitediatthe point S, as marked=on-the indicator card's'hown Fig; 8; anclbeing near the end' of the compression cycle, thepistonwill continueto rise until it reaches top dead-centeri- Normally",- the -vpressure rises to' its' peak in-a relatively-short angular movement of the crankshaft. present instance the dead-center load elim-i nated as a relativelyhighpressure; here indi cated at HOW-pounds; is-maintained over approxi mate]? 50= degreesof crank-pin travel In order to'- understand theexact operation otanengine embodying the present invention; =Tef== gramdisclbseddnFig. 9; Here it will be seen that when the piston is on topdead=center, as indicated in'--Fig; 4= of the drawing, the center lines oftheoscillating arms 26 and the radius arms'lt will' intez sect atright" angles to each other,v and at-the' pointofintersec'tion the axes of the crankshaftsectionsis w ill occur; The center of the-- oscillating arms 26 will also he in the same plane with-the=center of the engine cylinder; At this time the center of the eccentric: crankshaft-sections 23 will be" spaced. upwardly from: the: axis ofl'the' concentric crankshaft sections 23*. The axis-of the ecc'entric crankshaft section-23 is the fixed axisfor the crank-epinl'l, an-d'when the en-' gin'e is'on' to'p-dead-cente-r thecra-n'kpin 22' will ofcourse'lie in' thesanie vertical-plane as the pivotpin" 3!? and the intermediatecrank axes;- It is to be understoo'd thait the normal operation ofaf-ourcycle engin'e theaccumulator plate 33 M11 Witlr the present-invention the performance isindicated by the flex only during: that pofition or the power stroke shown: on the: indicator card byiwdottcd lines at appnoxihiately 600i pounds" pressure and: the eX treme pressures? indicated in soliti lines from 600 a tOQO'OilJOIIHds will be eli'minatedc 'Ihec'onditiom of" the engine parts at this time as showen in Fig-.filoi the drawing-Sis When however, the crank throw: moves toarr angle of-fromato deg-rees on its" power stroke the tensionstrength of the accumulator late-33 M11 balance out the forceand restore the plate 33 toits normal positiom of" equilibri u Itw-illbe appreciated thatduring the time th'e' accumul-athn plate 33 flexes: downwanliy the:- cranksha-ft structure swings vertically on theanc described from the axis of the power output shaft 42 and that when the accumulator plate 33 is-irestored 'toequilibrium the crankshaft unit-will'move-upwardlyon the arc described trom the axi or the power output shaft 42. Fur the1- more", it should be p'oin'ted out that this-axis is tangent to the vertical center line of the enginecylind'er. On the scavenging cycle of one cy1-in=-- d'er'- the equilibrium of the accumulator plato 3-3 is not d-isturb'edt- At that time the-crankshaft and its pins move in the manner specifically-shown iitFigzof the drawings; where it will besee'r-l that as the-crankshaft moves from dead-center to one quarter stroke it will rotate around the axis of theeccentric crankshaft section. However si-; multaneously therewith the axis of the concentric crankshaftsection must also-move, and-since the axis of the eccentric crankshaft section is con fined to horizontal travel along the-arc ofthe oscillating arms 2 6 and the axis oftheconcentric crankshaft section is confined to w travel ver ticall'y along-- the" arc of the-radiusarm 45- the axis ofthe-eccentric crankshaft section will moveto-thepoin-t X, from-its dead centerpoint W, and: at that time the "axisof the concentric shaft will move tothe point--WJ Simultaneously therewith the crank pin 22 Will-move'fi0mthepoint w to the point X. As the crank continues to rotate the axis of the eccentric crankshaft will move" backalongj the arc as 1 established by the oscillat ing arm' 2 5" tothepoint W, and'the axis ofthe concentric crankshaft will havemoved upwardlyalong the-arc defined by the radius arm 45 tothe 'point' Y, which-will be on dead-centerof the cylinder. At thistime the crank-pin 2?2'wil1 have traversed"one-halfofitsrevolution and will be at thepoint Y; As the crankshaft continues torotate inthe direction of the arrow a; a indi=-- cated in' Fig. 9; the axis of'the concentric crank-- shaftsection 23 will be compelled to move down w-ardly along the-arc defined by. theradius arm 46- while the axis of the eccentric crankshaft-sec tion- 23 -wil1 move downwardly along the radius 0f the-"oscillating arm Ziy 't'o the point Z. When: the point Z is reachedthecrank-pin 22 willheat the pointZ"; and asthe crankshafitmoves the crank -pin 22-- to itsoriginal dead-center position at- W" the eccentric crankshaft section=23 will move down alone thearc of theradius arm 45 to its original position at W, and theaxis ottheconcentric crankshaft section 123 will return:

ag ain teats-lowermost positional", V

The foregoing description traces the orbit of the"cranl :}pin- 22* when it is on its scavenging stroke} This has been done because-it is'muchsimpler to descrilde the relative movement of the concentric crankshaft sections- 23* and the eccentric crankshaft sections 23. It should be po'inted out; however; thatdue-to the fact that the pivot-shaft am carrying the os'cillati'ngarms =26 are mountedupon the accumulator plates-33 atapproximately the GOO-pound calibration on the indicator card, shown in Fig- 8 and which is illustrated in Fig. of the drawing, will cause all of a crankshaft unit 23 to move downwardly bodily on approximately dead-centerv as controlled by the vertical swinging movement of the radius arm 46. If we assume, by way of example, and with reference to the diagram shown in Fig. 9, that the amount of downward deflection is represented between the points V and W, then the crank-pin 22 will move downwardly more rapidly for a portion of its travel as represented along the GOO-pound calibration in Fig. 8. When the crankpin has traversed approximately 50 degrees the force of the deflected accumulator plate 33 will begin to balance out the force of the explosion in the cylinder, and at approximately the 500-pound calibration on the indicator chart the parts will be restored to the position indicated in Fig. 6 of the drawing, at which time the accumulatorplate .33 will again be in equilibrium and will continue to be so throughout the remainder of the power stroke and through the complete scavenging and induction stroke.

In briefly reviewing this operation it will be seen that the fuel is ignitedat the point S designated on the indicator chart in Fig. 8, and which is near the conclusion of the compression cycle of the engine. Thus, when the piston is at top dead-center the moment about the crankshaft axis is zero. As the pressure of the burning gases rises sufficiently the piston l3, connecting rod 20, crankshaft 23, and the radius arms 46 move as a unit about the axis of the power output shaft 42. Hence, the distance from the center of the shaft 42 and the center of the crankshaft section 23 becomes the instantaneous moment arm, and the entire-force acting upon the piston I3 will at that time be applied tangent to a circle described by the axis of crankshaft section 23 as it moves around the axis of the power output shaft 42.

When this takes place rotation will be imparted to the power output shaft 42 incident to the movement. By reference to Fig. 6 of the drawing it will be seen that the accumulator plate 33 has returned to its normal unfiexed position. This takes place approximately when the crankshaft has rotated 55 degrees beyond top dead-center. When this curve is plotted on the indicator card shown in Fig. 8 it will be observed that the point corresponds to a pressure of the order of 490 pounds per square inch. It will be noted that when the piston is at its top dead-center that one-hundred percent of the explosive force acting thereagainst is applicable as tangential force. This is entirely contrary to the performance of a conventional internal combustion engine, since as shown by solid lines on the indicator chart in Fig. 8 the tangential force for this position is zero. 1

It will be recognized that due to the relationship of the concentric crank axes to the eccentric crank axes and their floating supports, the crankshaft mass and arms 46 will move in a direction opposite to the piston movement. The product of the mass of the crankshaft and its acceleration will equal the product of the piston reciprocating mass and its acceleration. This insures one hundred percent balance of the first harmonic phase within the entire cycle of 360 degrees.

If a conventional type crankshaft is used with the accumulator plate mounting it is possible to balance out one-half of the first harmonic phase while obtaining the other novel advantages in operation, as previously explained.

In the foregoing explanation of the present invention all of the conditions described are full throttle conditions or when suflicient resistance to the rotation of the crankshaft is set up to overcome the inherent resistance of the accumulator plate and to force the plate to flex. It will therefore be evident that a high degree of engine efilciency will be obtained when the engine operates at half throttle.

It will thus be seen that by the use of an engine of the construction here disclosed and by practising the method of operating the same, a reciprocating type internal combustion engine is provided in which maximum substantially uniform torque is obtained, thus making it possible to produce a smoothrunning engine, the parts of which will not wear readily, and in the performance of which a high percentage of the explosive force applied to the piston is converted into useful work.

It will also be recognized from a study of Fig. 8 of the drawing that the explosive force of the engineis damped during its initial period and takes place under conditions which are not those of the usual high compression type of engine, thereby insuring an engine that runs smoothly and within which maximum engine efficiency is obtained with a minimum wear and vibrationv of engine parts, and thu a minimum strain thereon.

While I have shown the preferred form of my invention and method for practising the same, it is to be understood that various changes might be made in the combination, construction and arrangement of parts, as well as variations in the steps of the method, by those skilled in the art, without departing from the spirit of the invention as claimed.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a reciprocating type internal combustion engine having a cylinder, reciprocating piston, crankshaft, and connecting rod, the method of damping out the maximum explosive force exerted on a piston at top dead-center, which consists in supporting the. crankshaft by resilient means having a predetermined resistance value to said explosive force.

2. ,An internal combustion engine comprising a cylinder, a piston reciprocating therein in response to explosive force,-a crankshaft unit, a connecting rodbetween the crankshaft and the piston, a power output shaft parallel to the crankshaft, driving means between the crankshaft and.

the power output shaft, radius arms connecting the power output shaft and the crankshaft whereby the two shafts are held at a fixed radial length 7 concentric and eccentric crankshaft sections, the axes of which are. offset with relation to each.

other and both of which axes lie in a plane common to that of the crank-pin, a power output shaft parallel to the crankshaft, a radius arm pivotally mounted upon the power output shaft and" rotatably holding the concentric portion of the crankshaft at its outerend, the arc of the axis of the concentric crankshaft section being tangent to the longitudinal center line of the cylinder, an oscillating arm rotatably engaging the eccentric shaft section and extending downwardly beneath the crankshaft, a pivot shaft for the lower end of said oscillating arm, said shaft being parallel to the crankshaft and intersecting the longitudinal center line of the cylinder, the radial length of said arm being such as to dispose the axis of the eccentric shaft section above the axis of the concentric shaft section when the piston is on top dead-center, and constantly meshed driving gears, one carried upon the power output shaft and the other carried by the concentric crankshaft section.

4. The structure of claim 3 including a resilient support for said pivot shaft of the oscillating arm whereby the crankshaft unit may move downward bodily around the axis of the power output shaft as controlled by the radius arm until the explosive force within the cylinder is overcome by the inherent resiliency of the resilient supporting means.

5. The structure of claim 3 including a resilient support for said pivot shaft of the oscillating arm REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,604,625 Wickersham Oct. 26, 1926 1,687,425 Briggs Oct. 9, 1928 2,380,778 Murdock July 31, 1945 FOREIGN PATENTS Number Country Date 845,222 France Aug. 16, 1939

Images