US2575633A

US2575633A - Internal-combustion engine

Info

Publication number: US2575633A
Application number: US774542A
Authority: US
Inventors: Lugt Gerard Johan
Original assignee: Werkspoor NV
Current assignee: Werkspoor NV
Priority date: 1946-01-09
Filing date: 1947-09-17
Publication date: 1951-11-20
Anticipated expiration: 1968-11-20

Description

Nov. 20, 1951 G. J. LUGT 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 17, 1947 7 SheetsSheet 2 Nov. 20, 1951 LUGT 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 17, 1947 '7 Sheens-Sheet 3 FIGQ Nov. 20, 1951 J. LUGT INTERNAL-COMBUSTION ENGINE '7 Sheets-Sheet 4 Filed Sept. 17, 1947 M a? j I m l /J w u mu 4. m Z F m Nov, 20, 1951 I J LUGT 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 1'7, 1947 '7 Sheets-Sheet 5 NOV. 20, 1951 I G 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 17, 1947 1 '7 Sheets-Sheet 6 TF' W Nov. 20, 1951 7 Sheets-Sheet 7 Filed Sept. 17, 1947 Patented Nov. 20, 1951 UNIT- D 1 STATE PAT iNTEnNAmCOMBUsTIoN'ENGiNEf 1. p Grardflohan Lug't,'Amsterdam,Netherlandsyassignor to Werksp'oor N. -V.; a company of the Netherlands Application September 17, 1947, Serial Nb. 7.7;,542]

. I n vthel\let hferlan ds January 9, 1946 Section 1, Public Law 690; August 8, 1946 Patentexpires January 53,1966

. .Every internal combustion. engine comprises auxiliary'or controlling means which haveto be moved in correlation with. the movement .of. the piston(s) By .way; of: example, valves,; pumps (e. g -compressorsior fuel pumps) "and also indi- I cator'devices may be mentioned. Ina two-cycle engine of the longitudinal. scavenging .or unifiow type such a means may be, in particular the outletmeans in the cylindercover.,.. f i V Such-auxiliary and controlling means ,are usually drivenby meansof-a camshaft, or sometimes from the crosshead or. the crank shaft. From a constructionalpoint of viewthe devices required for this purpose arefcomplexandgespensive. According to the present invention, thejauxiliary and controlling means of .a cylinder which have to be moved in correlation with. the vrnoyementof thepistonare driven by an element that moves up and down in time with the piston in such a manner that this elementfand the piston pass: simultaneously through thedead centre; -a phase shifting mechanism being inserted; if necessary, between the auxiliary'or controlling means in question and the driving elementl' Preferably the driving element is the piston mechanism of a piston pump, particularly of "a scavenging air-pump. e l The above arrangement results in' theproduction-of simple, reliable and'relatively inexpensive constructions. I I

When the driving element in question and the piston pass simultaneously throughthe dead centre, the movement of: the-drivin element issymmetrical with respect to the dead centre of the I j. "13. can; (01.123540) mentwith respect to the driving. movement'has piston. This presentsithe advantagethat the movement .of the driving element with regard .to:-the movement of the piston isiindependent cfthe ,direction,;vof -rotation ,of. the crank shaft,

and consequently is thejsamei for both forwardf' and reverse rotation. Such a movementahowever, cannot be used assuch forthe movement of the outlet .valve of 1a. twpstroke engine having longitudinal scavengin fl0w.,;1 he anglepfrthe crank within which this valve {has to, open be fore the dead centreislarger than lthe angle within which it/ ha's .to close beyond .;the dead centre. This means that themove ne nt of the valve is not 'symmetrica-l with respect ,to the dead centre.

It does not seem diflicu lt toderive above mentioned symmetrical movement of ,the

Tri

.-.-.Accordi ng to..the.invention, the mechanism connecting,- the driving element to :the: auxiliary or controlling means driven by it containsato that effect at least :two elements which co-operate to give the required movement and one of which at least is :multiple with'function changing-parts or: is changeable in position, while a device isprovided which causes the said" changing of function or of positioninthe driving 'element=periodically. .1 w Inthe accompanying drawing: Fig. 1 is asectionalview'of the cylinder ore two'cycle internal-combustionengineof the uniflowor longitudinal type;"'-* f Fig. lais-asectionalviewof a two cyclein'ternal combustion 'engin'e showing "the cooperative relation of the driving meansjto'aiuel pump} a sectiontaken onthe linejll l llfi in Fig; '5 is aside view of another mbeq i entnf hi ani m; y I e v Big. 6 isa side view of a thirdembodim'ent, and

' Fi Tie a side viewofa; fourth embodiment. In Fig. l a cylinder,joffb l?ter; a. cyl inderliner "'l is shown, which is provided with scavenging ports 2, a cover being providedwith a number of 'outlet valves 3'. The pisfiQn. 4, iswrat her short, as

is usual with'this typeioi engine, and connected by'a' c'onnectingrod 5 toacranl; 6 ate crank vfshaft'l. I v ,4; A scavenging airpumpisfit ed next to the ens s l er end-con i t bf a Pum yl n erfi with a piston}, as.low as possible..in order. to permit .of lateral inspection. and sideward dismou'nting of the piston.4'.'; .Thefendof the piston section :takenfon the line II -II in 3 rod I is on a cross head II which moves along aguide I2.

Beneath the engine cylinder I and the pump cylinder 8 a lever I6 is pivoted upon the point I5. Its end is connected to the motor piston 4 by a connecting rod II, by which it is also driven. Further, the lever I6, in turn, drives the scavenging air pump through the medium of a connecting rod I8 applied to the cross head II.

The movement of the pump piston 9 will be not only in time with the motor piston 4, but even in entire conformity with the movement of the motor piston, only with a smaller stroke. The coupling of these two pistons forms a pantograph system.

A piston rod 22 connected to the pump piston 9 passes through a stufiing box in a cover 2I of the pump cylinder 8. A piston rod 22 forms the driving element for the auxiliary and controlling means.

The end of the rod 22 is provided with a cam body 23, against which a roller 24 is pressed. This roller 24 is mounted at the end of a leversystem 25, to which rocking levers 26 are connected, which levers control the valve rods 21 of the outlet valves 3. It will easily be seen that the shape of the cam 23 is such that at the end of the downward stroke of the motor piston 4 the outlet valves 3 open before the ports 2 open and that the outlet valves 3 remain open till the cylinder has been scavenged by air flowing through the ports 2 and the outlet valves 3. Adjustment can take place by varying the position of the cam 23 on the rod 22.

When it is required that the points of opening and closing of the valves or other elements are not symmetrical with respect to the dead centres, at phase-shifting mechanism must be applied in order to obtain the unsymmetrical movement required.

Furthermore the paper or registration drum 30 of the indicator mechanism is also driven from the rod 22, and a device for reversal and reduction of the movement is necessary. As such there is provided a shaft carrying cable drums 3I and 32 respectively of different diameters. on which the

cables

33 and 34 respectively are wound in opposite direction. The former cable is attached to the indicator, the latter to the rod 22.

When shifted diagrams are required (showing a phase-difierence of 90 with respect tothe engine), another device for transformation of movement is provided for that purpose (e. g. a crank mechanism with cranks at 90).

In the motor shown in the drawing, the starting valve device or its control device, the supercharging device (for introducing combustion air under pressure into the cylinder) and the fuel pump can be driven, controlled or regulated from the rod 22.

In Fig. let I have shown a fuel pump plunger a which is driven by a cam b on the piston rod 22 of the scavenging pump piston 9. The supply conduit for the fuel oil is indicated by reference character 0 and is connected to the fuel pump cylinder over a suction valve (1. When the pump plunger a has been retracted the oil will circulate from the supply conduit c to the pump cylinder and back to the return conduit e in order to keep the oil flowing constantly. The fuel injector is indicated by the reference character 1, and as a rule the injector f is not mounted on the corresponding motor cylinder I but on another cylinder of the same engine. It would be possible to have the injector f mounted on its own cylinder I but then a phase of shifting mechanism would be needed in order to obtain a longer injection period after the motor piston 4 has reached the outer dead center, which would complicate the design.

In Figs. 2, 3 and 4, a rod IIII forms the driving element. It may be, for example, the extended piston rod of a scavenging air pump driven by a balance from the cross head of an engine cylinder and consequently having a movement in the rhythm of the engine piston. The rod IOI carries a cross head I02 moving along the guide I03. and the cross head I02 carries a roller I04.

The outlet valve to be controlled is driven by a. rod I05, which is fitted to a lever I06 pivoting about a fixed point IB'I. It will be understood that When the roller I04 moves up and down along a cam-surface on the lever I06, this lever I06 pivots about its fixed point I0! and thus acts upon the rod I05. Care has to be taken, that the movement of the lever I06, when the roller I04 moves downward, is difierent from the movement of the lever when the roller I04 moves upward. This can be effected by an arrangement in which different cams on the lever I06 are in contact with the roller I04 when it moves upward and when it moves downward.

For this purpose the lever I06 is provided with a cam unit I08 comprising a set of cams I09 (three cams) and a set of cams III] (also three cams). The roller I04 consists of three coaxial discs of equal size co-operating with either the cams I09 or the cams H0. The position of the roller I04 is variable in axial direction in the cross head I02. When this roller I04 is in the position shown in Figs. 3 and 4, it co-operates with the cams I09, but when it shifts it co-operates with the cams III). Thi shifting is effected with the aid of an arm rocking lever I I I, which strikes an abutment H2 when the rod I0] moves downward. At the upper dead centre a shifting in the opposite direction has to be effected, and this can be done in the same manner by a rocking lever H3 co-operating with an abutment H4.

The position shown in Fig. 2 corresponds with the beginning of the opening of the outlet valve of the two-stroke engine. When the axis of the roller comes into the position indicated by the dotted line H5, the engine piston is at its lower dead centre and the movement reverses, the roller I04 now following the cam H0, so that the outlet valve is again closed when the axis of the roller is in the position indicated by the dotted line I I6.

The roller I04 is divided into separate discs (three, in the drawing) in order that a small axial shift may suflice. In position H5 the discs are in contact with both the cams I09 and the cams I I0, so that shifting can take place without shock. During the shifting at the lower dead centre an auxiliary roller (not shown) can be used in order to avoid contact between the roller I04 and the cams I09 and H0, so that shifting can take place without friction.

Of course the positions of the roller I04 and the cam I08 can be interchanged.

In the embodiment according to Fig. 5, as opposed to that of Figs. 2-4, the roller is immovably fitted in the cross head I02, but the cam is adjustable. For this purpose the lever I06 carries a single cam I20, which is adjustable with respect to the lever I 06, viz. by means of two links I2I and I22, pivoted at the points I23 and I24 respectively of the lever I06. The other extremities of the links I2Iand I22 are' pivoted'at the points""I25 andIZB' respectively of thecam." "At the downward stroke of*the rod*II'-the roller I04 pressesthe cam I20 against the fixed abutmentsl2! and I28 'ofthe -lever- 106. The cam I20 i moreover maintained in that position byatension spring I29, attached'to thejfree end of the'link I22.- The position and the shape of the cam Ilfl-aine such that' th'e rod' I05 is acted upon at-fthe correct mo'ment: Inthe' drawing the position corresponding with the initial opening of theoutlet valve isshown. It is to be noted that the links IZI- 'and I22 -arenot' understress', the-whole force being taken up by the abutments I21 and I28.

After the roller I04 has passed'the nose of-the cam and is consequently applied to the fixed *cam -I'I"9 'of the lever I06, the rod IOI'movesagain upward, and the' couple acting'on the cam I underthe influence of the pressure exerted'on =it by' the roller l04 is inverted, as-a resultof'which the cam' is moved upward intothe positionshown indott'ed linea i Consequently the roller I04 runs-upwards from the cam l-l9 alongacam surface of a shape or is closedz 1 The dotted line II5 mark the low'er dead centre. v In the embodiment of Fig.- 6-' the 'roller l04 forms a part of the lever I05, whereas the cross head I 02 is provided with the cam; The roller I04 '(which' may be multiple) is mounted in a yoke I pivoted at'a point I3I. A spring 132 maintains the shaft I33 of the roller I04 in contact with-a cam I34 on the lever I05.

When the-cross head-I02 moves downward, a I

cam; I35 touches the roller I04, as a result/of which the lever I 06'is-r'noved. The position illustrated corresponds with the beginning of this movement (opening 'of the outlet valve) 1 The lever- I06 carries another roller I36 which isalso: controlled by the cam I 35. cam I35 enters into contact with the roller I36, it loses contact with the roller I04, and when after having reached'the lower dead centre it again moves upward, the roller I 04 is pushed away and broughttothe position I 31 shown in dotted lines, so thatthe cam I35 i applied to the roller I 36 only. This means that the lever I06 quickly swings back, the dotted line IIB marking the 'pos'ition at which theclosing of the outlet valve takes place, and the positionof the cam within the path limited-by the dotted line I40 (beginning of the opening of the outlet valve) and the dotted line I4I (lower dead centre). The outlet valve (not shown) is controlled by a connecting rod I42. A lever I44 is fitted to this rod I42 at the pivot I43. The point I43 is conducted When this in i a circular path by means of a; link I45 pivoted at the fixed point I 45;the circle of which coincides as much asflpossible with the evolutevline described'by the point 443 iwhen -the lever I44 rolls or is evolved on a curved fixedttrack I41". Theoth'er end'of-the'lever .Ie4 (pivot I48) is connected'by means of a link I49=-to' a -pivot-I50at the extremity of the connectingnrod lfil moving upand down. 1=At the upper dead centres-ISIthis link occupies the position I4.9'eand the-pivot lc48 is atthe 'position- I48". The curved evolvingr'track I4! is pivoted at one endx-upona fixed pbintl52, while it rests at the'other end upon a two-sarm lever I53 pivoted at .the fixedz point1 I54: -At the lower deadtcentre the protruding"- pin I5 0 of. the rod IOI presses against theextremity 1550i the lever I 53,. as a sr'esult-of which-the latter :is put in the position shown inrdotted liness-andc-the guide I4 I; is "pressed downward, pivoting .upon the point -I 52, .into the position: shown in dotted lines against :the abutment I56: Consequently the point =-I 43 also drops; together: withthe pushing rod*I'42,l sothat in the upward stroke the closing ottheivalve comes earlier. Thetrack M Iis then again completely discharged and a springer-I51 causes the track I4Tand' the lever -I53-.to return totheir originalpositions. -1 This construction maybe variedrin manywa'ys. The track. I41 can be fixed :and themoving parts maynbesplaced inthe lever I444: The' p0inttI'43 may also-be guidedin' aright liner insteaduof pivoting uponpo'int I46, The abutment I58 may be provided with ia bufier-mechanismin orderto absorb the shock at-thelower dead zcentre. :zflhe principle of this latter construction is that no cams and rollers are used-but instead ofthese a. lever I44 rolls or evolves on-a curvedtrack I41, theposition 1of-1the track I4'I being different in the upward and downward movement ofthe connectingrod-IBI. :2-

.- I i What Iclaim is:- f- 5': I 1; A two-stroker'internal --combustion--. engine of :the uni-directional flow type,. comprising a :power cylinder closed-at one end, a reciprocatingpiston within the power cylinder, a lcranksshafizaconnecting rod and a crank 'operatively connecting the piston to the crank shaft, .said cylinder "being provided with outlet means in its closed .endand withair inlet ports inits wall-positioned rto-be uncovered by the piStOnrWhGIl it nearsits: inner dead :center, an air scavenger pump comprising a, pumpecylinder and-a reciprocating pump piston within r the r pump cylinder, the pump" cylinder being located adjacent the power cylinder; and the pump piston being provided with connecting rod mechanism aoperatively connected tothemoving piston systemvof the power cylinder and, also to the outlet means of I theflpower cylinder, the outlet passages of l the, air pump :being; in l .communication with .theairinlet ports inzthe wall of-the power cylinder; z =1 1 2. A two-stroke internalcombustionenginemf the uni-directional. flow type, comprising .azpower cylinder closed at one end, a reciproc'atingpiston within the power cylinder, a crankshaft, .a connecting rod and a crank operatively connecting the piston to the crank shaft,- said cylinder-being provided with outlet means in its closed end and with air inlet ports in its wall positioned to be uncovered by the pistonv when it nears its inner dead center, an indicator device mounted on the power cylinder, a pump comprising a pump cylinder and a reciprocating pump piston moving within the pump cylinder, the pump cylinder being located adjacent the power cylinder, the

7 pump piston being provided with connecting rod mechanism operatively connected to the moving piston system of the power cylinder and also to the movable part of the indicator device which has to be driven in phase with the power system.

3. A two-stroke internal combustion engine of the uni-directional flow type, comprising a power cylinder closed at one end, a reciprocating piston within the power cylinder, a crank shaft, a connecting rod and a crank operatively connecting the piston to the crank shaft, said cylinder being provided with outlet means in its closed end and with air inlet ports in its wall positioned to be uncovered by the piston when it nears its inner dead center, a fuel pump of the reciprocating type having its outlet communicating with a fuel injector, a second pump comprising a pump cylinder and a reciprocating pump piston moving within the said pump cylinder, the pump cylinder being located adjacent the power cylinder, the pump piston being provided with connecting rod mechanism operatively connected to the moving piston system of the power cylinder and also to the reciprocating driving member of the fuel pump.

4. A two-stroke internal combustion engine of the uni-directional flow type, comprising a power cylinder closed at one end, a reciprocating piston within the power cylinder, a crank shaft, a connecting rod and a crank operatively connecting the piston to the crank shaft, said cylinder being provided with outlet means in its closed end and with air inlet ports in its wall positioned to be uncovered by the piston when it nears its inner dead center, a pump comprising a pump cylinder and a reciprocating pump piston moving within the pump cylinder, the pump cylinder being located adjacent the power cylinder, the pump piston being provided with connecting rod mechanism operatively connected to the moving piston system of the power cylinder and also to the outlet means of the power cylinder and a phaseshifting device mounted between the connecting rod mechanism of the pump and the outlet means of the power cylinder.

5. A two-stroke internal combustion engine according to claim 4 wherein the phase-shifting device comprises cooperating means to transmit the driving movement from the said pump to the said outlet means, one of said cooperating means having two different active parts which cooperate one at a time with the other of said means, said active parts being periodically shiftable for cooperation with the other of said means.

6. A two-stroke internal combustion engine according to claim 4 wherein said phase-shifting device comprises a roller and a cam unit consisting of two cams in staggered relation with respect to one another in a direction at right angles to the direction of the movement, said roller and cam unit being adjustable in a transverse direction with respect to one another in such a manner that either one cam or the other cooperates with the roller.

7. A two-stroke internal combustion engine according to claim 6, in which with respect to the roller and the cam unit only, the one located in the driving element connected to the said pump is adjustable in a transverse direction by cooperation with abutment mechanisms near the ends of the stroke of the driving element.

8. A two-stroke internal combustion engine according to claim 4 wherein the phase-shifting device comprises a roller and a cam, one of which is movable in the plane of the relative movement from a working position to a, different working position, or from a working position to an inactive position, a second cam or roller being provided in the latter case, with which the roller or cam respectively, can cooperate when the first mentioned cam or roller occupies its inactive position.

9. A two-stroke internal combustion engine according to claim 4 wherein the phase-shifting device comprises a roller cooperating with a cam, the cam being movably fitted in its own plane by means of links, the movement being limited by an abutment in one working position in such a manner that when the relative movement of the roller reverses, or after it has been discharged from the pressure of said roller, the cam turns away, thus forming or disengaging a different shape cam surface to cooperate with the roller.

10. A two-stroke internal combustion engine according to claim 4 wherein the phase-shifting device comprises a roller cooperating with a cam, the roller being movably fitted in its own plane and supported in its working position by an abutment, a second stationary roller being provided to cooperate with the cam when the first mentioned roller passes to its inactive position under the influence of the cam reversing its relative movement.

11. A two stroke internal combustion engine according to claim 2 wherein the pump is an air scavenger pump, the outlet passages of which are in communication with the air inlet ports in the wall of the power cylinder.

12. A two stroke internal combustion engine according to claim 3 wherein the second pump is an air scavenger pump, the outlet passages of which are in communication with the inlet ports in the wall of the power cylinder.

13. A two stroke internal combustion engine according to claim 4 wherein the pump is an air scavenger pump, the outlet passages of which are in communication with the air inlet ports in the wall of the power cylinder.

GERARD J OHAN LUGT.

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

UNITED STATES PATENTS Bernard Oct. 24, 1933