AU726948B2 - Arrangement in a combustion engine with internal combustion - Google Patents

Abstract

A combustion engine (10) having internal combustion, comprises a number of engine cylinders (21), which are arranged in an annular series around a common middle drive shaft (11). Each cylinder includes a pair of pistons (44, 45) movable towards and away from each other and a common, intermediate working chamber (K) for each pair of pistons. Each piston (44, 45) is equipped with its piston rod (48, 49) with associated support roller (53) which forms a support against its respective "sine" - curve shaped cam guide device (12a, 12b), which controls movements of the piston relative to the associated cylinder. A least the one (44) of the two pistons (44, 45) in each cylinder (21) is regulatably adjustable axially in the cylinder especially for regulating the compression ratio in the common working chamber (K).

Description

The present invention relates to an arrangement in a combustion engine having internal combustion, comprising a plurality of engine cylinders, which are arranged in an annular series around a common central drive shaft and which have cylinder axes running parallel to the drive shaft, each cylinder including a pair of opposed pistons movable towards and away from each other and for each pair of pistons a common, intermediate work chamber, while each piston is equipped with its axially movable piston rod, the free outer end of which forms via a support roller a support against its curve-shaped, that is to say "sine"-like curve shaped, cam guide device, which is arranged at each of opposite ends of the cylinder and which guides movements of the piston relative to the associated cylinder.

SUBSTITUTE SHEET A SHEET From US 5 031 581 (1989) a solution is known correspondingly as indicated by way of introduction. More specifically it is proposed therein a four stroke combustion eng me having two separate cam guide devices. Each cam guide device cooperates with its respective set of pistons and with its respective associated set of support rollers according to a "sine"-like concept known per se.

In GB 2 019 487 a four cylinder two stroke engine is shown. The ignition occurs simultaneously in two of the four cylinders, that is to say in pairs of alternate cylinders. In the patent specification it is indicated that the contour of the cam can be designed so SUBSTITUTE SHEET 1;,.ifDLD SHEET that the pistons can be moved in a most favourable manner in connection with expansion of the combustion product. There is employed a desired level or steady contour for emptying or scavenging of exhaust before new fuel is introducec into the cylinder. In the drawings there is shown, in each of two mutually opposite cam grooves, a more or less rectilinear, local cam contour in mutual turning points lying directly opposite each other forming "sine"-like curve portions. More specifically the rectilinear cam contour is illustrated in only the one of two succeeding, turning points of the "sine"like curve forming "sine"-like curve portions, namely where the respective pistons occupy one after the other their most remote outer positions with exhaust and scavenging ports open to the maximum.

The present invention, which primarily relates to two cycle engines, but which can also be applied to four stroke engines, takes its starting point as to arrangement in the piston and cylinder arrangement according to the aforementioned US 5 031 581.

In FR-A-2 732 722 it is illustrated a two part driving shaft. Each drive shaft part is provided with a disc shaped cam guide device arranged in an inclined plane to the drive shaft axis to generate a mathematical sine-curve movement of the relevant one piston of each pair of opposed pistons. It is proposed to control the compression ratio by axially adjusting the relative distance between the drive shaft parts and accordingly the relative distance between each pair of opposed pistons. This axial adjustment is provided by axially movement of one drive shaft part in relation to the other drive shaft part, i.e. one drive shaft part is axially movable and the other drive shaft is axially immovable.

SUBSTITUTE SHEET tPliJ"NDE SHEU T 3a With the present invention the aim is to be able to regulate the compression ratio in cylinders of the engine in a similar way as suggested in FR-A-2 732 722, but with additional advantages. It is of especial interest tk provide an engine construction operating in a controlled, precise and reliable manner based on a constructional simple and reliable drive shaft structure.

It is a further aim of the present invention to employ a "sine"-like curve shaped, cam guide device instead of the disc shaped cam guide device suggested in FR-A-2 732 722. By the use of a "sine"-like curve shaped, cam guide device it is made possible to guide the associated pistons in a more advantageous manner to improve the total engine effect. More detailed the "sine"-like curve shaped, cam guide device enables incorporation of different local variations in each engine stroke in order to improve the total engine effect. It is, however, of utmost importance that the cam guide devices and their connection with the drive shaft have a favourable design and are sufficiently reliable in operation.

The arrangement according to the invention is characterised in that at least one of the cam guide devices is axially movable in relation to a one-piece drive shaft and is provided with a hydraulic mechanism, for separately adjusting the position of said at least one guide device, including regulation of the relative spacing between the pistons, said hydraulic mechanism includes an annular pressure oil chamber and a simulator piston, said simulator piston is partitioning said chamber into two sub-chambers, and each chamber is connected to a respective one of two pressure oil circuits.

SUBSTITUTE

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AM;iENDED SHEET By regulating the position solely for the one cam guide device the regulation arrangement is rendered especially simple and other significant advantages can be obt2.*ed in the general function of the engine, as will be described further below.

Alternatively, to regulating the position for only the one cam guide device, it is possible to regulate the position for each of the cam guide devices synchronously or individually, all according to the requirements for additional adjustment between the movements of the pistons in each piston pair.

According to the invention one is in a position to regulate the compression ratio in the working chamber between two pistons of the or each cylinder of the engine in a rather simple and reliable manner by means of said hydraulic mechanism.

SUBSTITUTE SHEET

AL

kahVDED SHEET K "N~T By the fact that the cam guide device is common to the one piston of each and all the cylinders there can be achieved effectively and in an accurately controlla4e manner corresponding regulation of the position for said one piston of each of the cylinders relative to its associated cylinder by means of one and the same pressure oil regulated cam guide device. This means that the position of said one of the guide means and accordingly the position of the related piston of each pair of pistons can be adjusted in controlled and reliable manner by means of a rather uncomplicated hydraulic mechanism, i.e. by means of pressurised oil.

SUBSTITUTE SHEET AMEiNDED SHEET According to the invention it is made possible to regulate the working volume between pistons of the cylinders as may be required, that is to say during use, and particularly during cold start of the engine and back to normal operation after the engine is run sufficiently warm.

A favourable constructional solution of the present invention is that a one-piece drive shaft is being used and that each cam guide device is rotative with the drive shaft and that at least one cam guide device is axially movable along the drive shaft. This means that the cam guide devices and the drive shaft can be realised in rather compact and dimentionally restricted construction.

A further favourable constructional solution of the present invention is that the pressure oil chamber is defined in an annular spacing between the drive shaft and the cam guide device, and that said piston is projecting from its cam guide device radially inwardly in said chamber.

It is also advantageous that the piston is passed through parallel to the axis of the drive shaft by a set of driving bolts, which allow a certain axial movement of the piston relative to the drive shaft, while the driving bolts are connected at their respective opposite ends to the drive shaft and connected to a carrying member fastened to the drive shaft.

SUBSTITUTE SHEET kINDED SHEE! It is especially interesting according to the invention to change the compression ratio in connection with the starting up of the engine, that is to say on cold s-art. It is furthermore interesting in addition to be able to change the compression ratio during operation in order thereby to obtain a most favourable compression ratio possible during normal operation. Consequently it can be of interest to change the compression ratio during operation of the engine for various reasons.

It is preferred according to the invention that the one piston of the cylinder, which is designed to regulate the position of in the associated cylinder, constitutes a piston which controls opening and closing of exhaust ports of the cylinder.

In practice said one piston of each cylinder controls opening and closing of one or more exhaust port(s) of the cylinder and the other piston of each cylinder controls opening and closing of one or more scavenging port(s).

Accordingly, at the same time as the compression ratio is regulated between the pistons, there is in addition achieved the possibility to regulate the opening and closing sequence of the associated exhaust ports.

Inter alia the flow-through passages of the exhaust ports can hereby be defined as required. Further the moment of opening and closing of the exhaust ports can be displaced in relation to normal operation.

SUBSTITUTE SHEETT A~3~'DED SI~{T Inter alia one can hereby achieve according to the invention a favourable separate control of the exhaust ports via the one group of pistons and separate, favourabit control of the scavenging air ports via the SUBSTITUTE SHEET b\C~SL;: AME!NDED

SHEET

other group of pistons via their respective separate cam guide devices.

Further features of the present invention will be evident from the following description having regard to the accompanying drawings, which show some practical embodiments and in which: Fig. 1 shows a vertical section of an engine according to the invention.

Fig. la and ib show in a corresponding segment of Fig. 1 vital parts of the engine and illustrate in Fig. la pistons of the engine in a position with maximum mutual spacing and in Fig. ib pistons of the engine in a position with minimal mutual spacing.

SUBSTITUTE SHEET AMENDELD SHEIEET 9 Fig. 2 shows schematically a first cross-section illustrated at one end of the cylinder of the engine in which there is shown a scavenging air intake.

Fig. 3 shows schematically a second cross-section illustrated at the other end of the cylinder of the engine, in which there is shown an exhaust outlet.

Fig. 4a shows schematically in a third cross-section, the middle portion of the engine cylinder, where the fuel is supplied and the ignition of the fuel occurs, illustrated in a first embodiment.

Fig. 4b shows in a cross-section, which corresponds to Fig. 4a, the middle portion of the cylinder according to a second embodiment.

Fig. 5a shows in longitudinal section a segment of the engine according to Fig. lb.

Fig. 5b shows a cam guide device with associated drive shaft, illustrated in longitudinal section with a segment of the engine according to Fig. lb.

Fig. 5c shows a cross head in side view.

Fig. 5d and 5e show the cross head according to Fig.

seen respectively from above and below.

Fig. 5f shows the piston rod seen in side view.

Fig. 5g shows the piston rod according to Fig. seen from above.

Fig. 5h shows a piston according to the invention in vertical section.

Fig. 6 8 show schematically illustrated and spread in the plane of the drawing a general pattern of movement for a first of two pistons associated with each cylinder, used in connection with a three cylinder engine, and illustrated in different angular positions relative to the rotarv movement of the drive shaft.

Fig. 6a shows schematically the principle for transferring motive forces between the roller of the piston rod and an associated obliquely extending portion of a "sine" plane.

A WEIN DEED S-7 Fig. 9 shows schematically illustrated and spread in the plane of the drawing a more detailed pattern of movement for two pistons of each cylinder, illustrated in different angular positions relative to the rotary movement of the drive shaft, illustrated in connection with a five cylinder engine.

Fig. 10 shows in a representation corresponding to Fig. 9, the pistons in respective positions relative to associated cylinders, in a subsequent working position.

Fig. 11 shows schematically a segment of a central portion of a "sine" plan for two associated pistons of each cylinder.

Fig. 12 shows a detailed curve contour for a "sine" plane for a first piston in each cylinder.

Fig. 13 shows a corresponding detailed curve contour for a "sine" plan for a second piston in each cylinder.

Fig. 14 shows a comparative compilation of the curve contours according to Fig. 12 and 13.

Fig. 15 shows in section and in longitudinal section an alternative construction of a cam guide device with associated pressure rollers arranged at the outer end of a piston rod.

Fig. 16 shows the same alternative solution, as illustrated in Fig. 15, shown in section in a direction radially outwards from the cam guide device.

Fig. 17 and 13 show in elevation and in horizontal section respectively the guiding of the head portion of the piston rod along a pair of control bars extending mutually in parallel.

In connection with Fig. 1 a two cycle combustion engine 10 having internal combustion shall generally be referred to herein. Especially there shall be described such a motor 10 adapted according to a so-called "sine" concept. In Fig. 1 there is illustrated in particular a Scombustion engine 10 according to the invention shown in cross-section and in a schematic manner.

AMENrDED SHEET Tn Fig. 1 there is shown a combustion engine having internal combustion, according to the invention, illstrtedin cross-section and in a schematic manner. As an embodiment there is shown a two cycle combustion engine 10, but as mentioned the solution can also be amnlied to a :ocur cycle engine, without the sreci fic embodiment of this be-,ia described herein.

According to the present inventiJon there is sl:eci-fically proposed a solution for changing the compression ratio ofthe engzine during use. The change of the comvression ratio will however also be able to have an 00 -Fuence on remainincr onerating odtoso the engine 0 00: as will be evident form the following descr-ition.

*:Go*:The following descrip=tion refers to different asmects 1n according to the invention which have direct or ind~rec+r significance for variJous functoso the engine and ertects following from this.

a Accordng t~o the invention an objective is inter alia :avourab. le control of the opening: and closing of exhaust zorts 25 and scavec;-an ito__-s 24 as will be described :urtnher .oel w.

Furrnhermore the aim -is combustion in a spDecially eZtined combustio;.n chamber K1, as will be described in Sdetail, below.

5 in he __ustrated embodi:ment a drive shaft is constructlonal v shown intefr fa drive stu=p shaftr .wr~c- -,:asses ax'a_-'lv anrd cezntrally truhthe engine eeThe drive sha'f I- is =-rvided with a first: head torion 2a roetgraal>. outwards, which constitzesa _frszcam guide device- The ,drive shaft: is rurtner t--rovided wvit.- a second head tortrion. 12b projecting eautaletlvoutwards, wnt'cnh conszitutes a second cam c=uide device.

Th'-e hea--d tortions! the cam guide devices 12a,12-b in1 t he i1llustrazed embodimenz are represented separately and are connected separately to the drive shaft I11 each with their f-asteninc means.

fiMENDED SHEET 12 The cam guide device 12a surrounds the drive shaft 11 at its one end lla and forms an end support against end surface lib of the drive shaft 11 via a fastening flange 12a' and is stationarily secured to the drive shaft via rastening screws 12a'' The cam guide device 12b surrounds a thickened portion 11c of the drive shaft 11 at its opposite end portion 1d. The cam guide device 12b is not, as is the cam guide device 12a directly secured to the drive shaft l1, but is on the other hand arranged axially displaceable a limited extent axially along the drive shaft 11, especially with the idea of being able to regulate the compression ratio in cylinders 21 of the engine 10 (only -he one of a number of cylinders is shown in Fig. 1) 1 5 End portion 11i (see Fig. 1 and 5a) of the drive share 11 forms a radially offset sleeve portion to which nere is fastened cup-shaped carrying member 13. The carrying memner 13 is provided with a fastening flange 13' n..ch with fastening screws 13'' is secured to end portion 3 C. c: e drive shaft 11. Between upper end surface 13a r -e carry:ng mem er 13 and an opposite shoulder surface Ie Cf the drive shaft 11 there is defined a pressure oil :hamber 13b. In the pressure oil chamber 13b there is siidably received a compression simulator 12b' in the form rf a pisCon-forming guide flange, which projects from the -nner side of the cam guide device radially inwards into :he pressure oil chamber 13b for sliding abutment against .ne outer surface cf the end portion lld.

In order to prevent mutual turning between the cam guide device 12b and the carrying member 13 and the drive shaft 11 the guide flange or simulator piston 12b' is passed through by a series of guide pins 12' which are anchored in their respective bores in the end surface 13a of the carrying member 13 and in the shoulder surface lie of the drive shaft S 11.

SUBSTITUTE SHEET AMENDED SHEET 13 The pressure oil chamber 13b is supplied pressure oil and is drained of pressure oil via transverse ducts llf and lig through end portion lid of the drive shaft 11.

An oil guide means 14, which is put axially inwards into mutually aligned axial bores in the end portion lid of the drive shaft II and in fastening flange 13' of the carrying member 13, provides for pressure oil and return oil to be led to and from the ducts llf and llg via separate guide ducts 14a and 14b and adjacent annular grooves 14a' and 14b' in the oil guide means 14.

Control of pressure oil and return oil to an from the pressure oil chamber 13b on opposite sides of the compression simulator piston 12b' of the cam guide device 12b takes place from a remotely disposed commercially conventional control arrangement, not shown further, in a manner not shown further.

The drive shaft 11 is, as shown in Fig. 1, connected ac opposice ends to equivalent drive shaft sleeves 15a and The sleeve 15a is fastened with fastening screws C -c che cam guide device 12a, while the sleeve 15b is fastened with fastening screws 15b' to the carrying member 3. The sleeves 15a and 15b are rotatably mounted in a respective one of two opposite main support bearings 16a,16b, which are fastened at opposite ends of the engine 0 in a respec:.-e end cover 17a and 17b.

As shown in Fig. 1, the end covers 17a and 17b are correspondingly fastened to an intermediate engine block 17 by means of fastening screws 17' Internally in the engine 10 a first lubricating oil chamber 17c is defined between the end cover 17a and the engine block 17 and a second lubricating oil chamber 17d between the end cover 17b and the engine block 17. There is shown an extra cap 17e attached to the end cover 17b and an external oil conduit 17f between the lubricating Soil chamber 17c and :ne oil cap 17e. Further there is Sillustrated a suct:-n strainer 17g connected to a lubricatinc oil conduit 17h which forms a communication SUBSTITUTE

SHEET

A~EI~DED SIWET 14 between the lubricating oil chamber 17d and an external lubricating oil arrangement (not shown further).

The oil guide means 14 is provided with a coverforming head portion 14c which is fastened to end cover 17b of the engine 10 with fastening screws 14c'. Th2cover-forming head portion 14c forms a sealing off relative to the lubricating oil chamber 17c endwise outside the support bearing 16b. Correspondingly there is fastened to the end cover 17a endwise outside the support bearing 16a a sealing cover 14d with associated sealing ring 14e.

The engine 10 is consequently generally constructed of a driven component, that is to say a rotatable component, and a dr:ving component, that is to say a nonrotating component. The driven component comprises drive shaft 11 of the engine and carrying member 13 of the drive shaft and drive shaft sleeves 15a,15b plus the cam guide zevices 12a and 12b, which are connected to the drive shart 11. The driving, non-rotating component comprises 20 cylin.ders 21 of the engine with associated pistons 44,45.

According to :he present invention there is ensured a reguiaticn of the compression ratio of the engine by effecting a reguiation internally, that is to say mutually between the parts of the driven component. More specifically the one cam guide device 12b is displaced axially backwards and forwards relative to the drive shaft 11, that is to say :..ithin the defined movement space in said pressure oil chamber 13a, which is determined by the guide flange 12b' and the part-chambers of the oil chamber 13a on opposite sides of the guide flange 12b'.

In practice it is a question of a regulation length of some few millimetres for smaller motors and of some centimetres for larger engines. The respective volume differences of the associated working chambers have however equivalent compression effects in the different T" engines.

A f 1E tED S'EET For instance a stepwise or stepless regulation of the compression ratios can be considered according to need, for examDle adapted with graduated control of the cam guide device 12b to respective positions relative to the drive shaft 11. The control can for example occur automatically by means of electronics known per se, based on different temperature sensing equipment, and the like.

Alternatively the control can occur by manual control via suitable regulation means, which are not shown further herein.

By effecting the regulation of the cam guide device 12b in connection with the driven component of the engine, one avoids influence on the general control of the arrangement of associated piston 44, piston rod 48, main 1 su-Dort wheel 53 and auxiliary wheel 55, that is to say influence on the mechanical connection between the driving comonent and the driven component is avoided.

On the other hand, with such a regulation of the cam rie device 12b, :here is obtained an axial regulation i-ternall In the driving component, in such a way that :he arranaement cf piston 44, piston rod 48, main support wheel 53 and auxiliary wheel 55 can be displaced collectively via zhe cam guide device 12b relative to the associated cylinder 21, independently of the concrete comDressicn regulation in practice.

In Fiq. 1 and ib there is indicated by a broken line a centre soace 44' between the piston heads of the pistons 44,45 at a normal ccmpression ratio when the cam guide device 12b occu:es the position illustrated in Fig. 1. By the full line there is indicated a centre space 44' between the pistcn heads of the pistons 44,45 when guide flanae 12b' of the cam guide device 12b is pushed to the maximum upwardly against the shoulder surface lie of the ciston rod !1.

The engine 10 is shown divided up into three stationary main components, that is to say a middle member, which constitutes the engine block 17 and two AMENDED SHEET 9 16 cover-forming housing members 17a,17b which are arranged at a respective one of the ends of the engine 10. The housing members 17b, 17c are consequently adapted to cover :heir respective cam guide devices 12a,12b, support wheels 53 and 55 and their associated bearings in respectiPe oiscon rods 48,49 at their respective end of the engine block 17. All the driving and driven components of the engine are consequently effectively enclosed in the engine and received in an oil bath in the associated lubricating oil chambers 17c and 17d.

In the engine block 17 in the illustrated embodiment, there is used in connection with a three cylinder engine, correspondingly designed with three peripherally separated engine cylinders 21. Only the one of the three cylinders S 21 -s shown in Fig. 1, la and lb.

The chree cylinders 21, which are placed around the drive shaft 11 with a mutual angular spacing of 1200, are descined according to the illustrated embodiment as searate cvlinder-forming insert members, which are pushed S into an associated bore in the engine block 17.

In each cyiinder/ cylinder member 21 there is inserted a sleeve-shaped cylinder bushing 23. In the bushing 23 there is designed, as shown further in Fig. la and Ib (see also Fig. 2 and an annular series of scavenging ports 24 at one end of the bushing 23 and an annular series of exnaust ports 25 at the other end of the bushing 23.

Equivalently -n wall 21a of the cylinder 21 there are arranged scavenging ports 26, which are radially aligned with scavenging ports 24 of the bushing 23, as is shown in Fic. 2, while exhaust ports 27, which are radially aligned with exhaust ports of the bushing 23, are equivalently designed in the cylinder wall 21a, as is shown in Fig. 3.

In Fia. 1 there is shown an annular inlet duct 28 for scavenging air, which surrounds the scavenging ports 26, S and a scavenging air intake 29 lying radially outside.

AMENDED

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C

C

As is shown in Fig. 2 the scavenging air ducts 28 extend at a significant oblique angle u relative to a radial plane A through the cylinder axis, specially adapted to out the scavenging air in a rotational path 38 internally -n the cylinder 21, as is shown by an arfbw B in Fig. 2.

There is further shown in Fig. 1 an annular exhaust outlet duct 30, which surrounds the exhaust ports 27, plus an exhaust outlet 31 emptying radially outwards.

In Fig. 3 there is shown an equivalent oblique run of the exhaust ports 27 at an angle v relative to the radial plane A through the cylinder axis, specially adapted to lead the exhaust gases from the rotational path 38 internally in the cylinder in an equivalent rotational oach outwards from :he cylinder 21, as is shown by an arrow C. The exhaust ports 27 are shown opening radially outwards to facilitate the outward flow of the exhaust gas from the cylinder :1 outwards towards the exhaust outlet duct In nhe convent:onally known manner the scavenging air is used to cush out exhaust gas from a preceding cocmustion phase in the cylinder, in addition to supplying fresh air for a subsequent combustion process in the cylinder. In this connection there is employed according to the invention n a manner known cer se a rotating air mass as shown by arrows 38 (see Fig. la and 4a) in working chamber K of the cylinder 21 in the compression stroke.

In Fit. la,lb and 4a there is shown a fuel injector or nozzle 32 received in a cavity 33 in the cylinder wall 21a. The injector/nozzle 32 has a pointed end 32' (see Fig. 4a) projecting through a bore 34 in the cylinder wall 21a. The bore 34 passes through the cylinder wail 21a at an oblique angle, -hich is not marked further in Fig. 4a, but which corresponds to the angle u, as shown in Fig. 2.

S 5 The pointed end 32' projects further through a bore 35 in i the bushing 23, in alignment with the bore 34. Mouth 36 S (see Fig. 4a) of the nozzle/injector 32 is arranged so r 3usH£ i<k S0HT C 18 that a jet 37 of fuel can be directed, as is shown in Fig.

4a, obliquely inwards in a rotating mass of air as shown by the arrows 38 in cylinder 21, just in front of a spark plug 39 (possibly ignition pin) arranged in a chamber zone S which forms a part of the combustion chamber K1 (se Fig.

lb).

In Fig. 4b there is shown an alternative construction of the solution as shown in Fig. 4a, there being employed in addition to a first fuel nozzle 32 and a first ignition arrangemen: 39 a second fuel nozzle 32a and a second ignition arrangement 39a in one and the same disc-formed combustion chamber Kl. Both the nozzles 32 and 32a are designed correspondingly as described with reference to Fig. 4a and both the ignition arrangements 39 and 39a are corresponding as described with reference to Fig. 4a. In :he nozzle 32a the associated components are designated with the reference designation in addition.

In the illustrated embodiment of Fig. 4b the nozzles 32,32a are shown mutually displaced an angular arc of 1800, S while the igniticn arrangements 39,39a are correspondingly shown mutually displaced an angular arc of 1800. In practice the relative spacings can be altered as required, that is to say with different mutual spacings, for instance depending upon the point of time of the mutual S ignition, and the like.

Further there is indicated in Fig. 1 a cooling water system for general cooling of the cylinder 21. The cooling water system comprises a cooling water intake not shown further having a first annular cooling water duct 41 and a second annular cooling water duct 42. The ducts 41,42 are mutually connected via an annular series of axially extending connecting ducts 43 (see Fig. The axially extending ducts 43 pass through the cylinder wall 21a in each intermediate zone 27a between the exhaust ports 27, so that these zones 27a especially can be prevented from superheating by being subjected locally to a flowing %ik through of cooling medium. The discharge of cooling water, i<< AMENDED

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which iJs not: shown further in Fig. 1, 4s connecte to the cooling water duct 42 remote rrocm the cooling water Intake, ~na manner niot snown ~rhr ntena~Y n the bushing 23 there are two axially movable Tpistons 44,45 movable towards and away :rom eacn other justby te resnective toto 44a,45a of the piston and by; thle skirt edae 44.b,45b Of the piston there is arranged a set of nizon -feathers a manner known ter Se. TLhe Cistons 44,45 are movable synchronously towards -t0 an wYfocahaher in a two cycle engine system.

7urzther-details of the tistons are shown in Fig. oThe inisto-n 44 is shown in the fcrm of a relatively thwallIed ca= having zop portion 44a and ski rt =ortion 44.

1ros the 'n-Cernal hollow spDace of the piston there IS is~ arrage a suttortr- disc 44c, thereafter follows a head me=er 48C for an associated =isson, rod 48, a suttocrt ring OS* 4d and a c.aron rng 44e.

:re ned memner 48c is -provided with a convexly =unded tpsur:ace 48c'I and ccncavely rounded of-f bottom :0 surface 48',w~the suttocrt disc 44c is designed with an zuIa~nz conc_=VeIy rounded Utter suttOrt_ surt1ace 44c' the support r :ng 44d is povided with a con-vexiL rosunded lower- support- surface 44d, The head member 48C i cansevcrunnI, adapz-ed to 1:e tiIlted about a theoretical axis %r Z 2C lciston otr.L by thIe sutt-ort surfaces 4 4 c d-d' .y ab0'trne'ent agal nst a shoulder -torzion 44ZF 0 -~~eralZ ~e ~st~ on r n- 4eProvides f Or h =-dc merner 4Sc -and thereby the pi'ston rod 48 having a certa=in dearee 0z and therebv a certain or 4t urn=in azout sald zheoretlical axis Of thepitn4 Thte -,emc e is -rovicded wi-:h a midd-le, 3LeveSha or:-icn 43c h-aving ri-b portions 48~ oo~e~t~~~lyoutwars wic form a locir.ng 3 nggeet ~t euvalenz caviTties (no: shown further) in~ena~~V iz-h associ-atec stofl rod 48 (e i.l and _1b) A:MEND ED. 3 -_JZT r In Fig. ia the pistons 44,45 are shown in their eauivalent, one outer position. This outer position, where here is a maximum spacing between the pistons 44,45, is desianated herein generally as a dead point Oa for the iston 44 and Ob for the piston In the said dead point positions Oa and Ob the piston 44 uncovers the scavenging ports 24, while the piston uncovers :he exhaust ports 25, opening and closing of the scavenging ports 24 being controlled by positions of the ciston 45 in the associated cylinder 21, while opening and closing of the exhaust ports 25 is controlled by positions of the Discon 44 in the associated cylinder 21. This control will be described in more detail in what follows having regard to Fig. 12-14.

in addition this control will be described with additional effects having regard to the afore-mentioned reoulation of the cam cuide device 12b along the drive When -he pistons 44,45 occupy their opposite outer 3 csi:tions, .here there is a minimal spacing between, as is shown in Fi,. lb, chese positions are usually designated as dead cpont posizzons. However according to the present invention :he pistons 44,45 are stationary, that is to say without or broadly speaking without axial movement relative to each other in and at these dead point ocsitions. In that :he pistons are held stationary not only in the dead pzcnt position, but also in adjacent portions of the respective "sine" plane, as will be described further below, a volumetrically more or less constant working chamber (combustion chamber) over a certain arcuate len=th can be ensured, that is to say over a considerably longer portion of the "sine" plane than nown nitherto.

Consequently :he pistons 44,45 are at rest or broadly speaking at rest over a portion of the "sine" plane, which is designated herein as a "dead portion" 4a for the opiston 44 and as a "dead portion" 4b for the piston

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21 Such dead Cortjons 4a and 4b are further illustrated in Fia. 12 and 13.

nsaid dead zortiofs there is defined in the working chamber K a so-called "tdead smace', which herein (for rSonsl wnich will be evident from what followsj is designate. as the combustionl chamber KI. The combustionl chamber K! 1s according to the invention mainly defined in and a= a transition -cortion be,_weei the c=moression -chase and e=an5ion phase of the two cycle engine, as will he described more detail in what follows.

Dur2gthe exoansion chase, that is to say from the position of the piston as Snown in Fi. lb to the -oosition of the :iston as snown -Jr Fig. l tne working chamber

K

is exan f rom a mum volume, shown by the combustion chamber Kl, gradually to a maximum volume, as shown in Fica. I a and a=t said dead -coin: Ca and Ob in Fig.12 and 1 3 thecmbsti-on onaMber KI beig radually excanded wit anoher- namer -K2 __whicoh the ex-oans ion and comcression Strokes of the csn544,45 taike plIace.

Ac ccr:n to4 the in-thn e combustion chamber

KI

Of ;s def-ne'd to a co-nsIderable dearee in said dead :rt-on/dead space. _n practice however the combustion can *also Con ;inue a b 7 cust su:de sald dead spDace, Some thin(7 whi ch will 1be e:Ilned _17 more tetail below.

c7 ncto-,t h chance of the comcression, ratio in tewor-kin c-namzer there can he a cuestion In the -os_7ti-n as snown in z~g 10 about different volumes in' tecrdton:aer K7 l according to which srouato is e::ectzed during -,se of -:ne engine. From 7_'-e 2 0 above tnere should 17n that case also be a question about ~i::~eft vlumes in te cc~slnc-a~er in the C-ost ~0I~n Snown ;n Kowev rie be aware of nh cston strokes for the indv:u.szn 44,,:5 b:eing precisely equally ln unaier all!-' alv conditions, recardless of the rat:."o Whichf must e-mrloved.

22 _kccortdfg to the inventicn the combustion chamb-er

K!

sdeF-,Ined to a considerable degree in said dead portion/ stace. In pract:Oe however the combustion can also cont-nue a bit Just ou~tie sadt dead space, somethig which will be explainecdi more detail below.

7Each ziston 44,45 is rii-yconnected to its res-mectilve pipe-shaped piston rod 48 and 49, which is guided in a rectili. ;:near movement via a so-called crosshead control SO. The cross-head control 50 is arranged tCartly in the engline block 17 and partly in the respective cover memner 77a and 17b a: the equivalent free outer end of the respective piston rod 4S,49. The cross-head control 0,which -is shown -i detail -In Fiz 5a, forms an axial 3 cuide for the niston rod 48 and 49 just within anrd just ouZSde the engine block 17.

With reference to Fiz. 5a thlere is a rotarv ;,in 51 *A J wnio -E as-tened at one end of the pipe-shaped piston rod and which zasses zhrouah piston rod 48 crosswise, S to say t.nrouah it.s czite hc lo w szace 52O a 4dle Cortio .1Z;7a C~ th_,e rotar pin 51, that- is to say ~enal iy sa2it hollocw szace 52, there ~s =otazablY 033mounted a mi caszcr 53, while on one end portion 51h of rotar p04- o the outwardly fac~na side 48a of the o* 25 tiston -rod 48 tnere is rot_=ta]:l mounted an auxiliary 3* n' L n castor 53 cowi-rses an inner nub) port-Of o 53a havin ,Il e bear-n z5t and an outer rim portio :Thre rimn ccr:on 5-3c Ls provided with a double curvedL, th-at to say Secto-r-Snaped rolle surfrace 53c' -0 The axlrycastor 55 haas a constru.ction corrstolt~E t t~main castocr 53 and comprrises an- inner trtin mddle rcle boearino S~ nd an ue rm 0o:o 0 5 i: b W all sec-zor-shamed roller surfa~ce ma~ castor 53 s adapted to bne rolled off along K- aroller su:c 4concavelY7 curved in cross -sect",On, whic ors a co: a so-calldIsnl curve 54' a

AMENDFDSHEET

shown in Fig. 6 8. 3y employing a ball sector-shaped roller surface 53c', which rolls along an equivalently curved guide surface 54 of the cam guide device 12a and 12b, an effective support abutment can be ensured between :he castor 53 and the guide surface 54 under varying working conditions, and possibly with a somewhat obliquely disposed castor and/or obliquely disposed piston rod 48 (49), such as this being able to be permitted in the pivotable mounting of the piston rod 48 in the piston 44, as shown in Fig. The "sine" curve 54' is designed in the cam guide device 12a and 12b of the drive shaft on a side facing eauivalently axially outwards from the intermediate linder's 21. The auxiliary castor 55 is adapted to be rolled off against and along an equivalent, other "sine" curve (not shown further) concaveiy curved in crosssection along a roller surface 56a in a roller path, which is desianed in the cam guide device 12a (and 12b) radially :0 -usz within the roller surface 54.

:n the embodiment illustrated in Fig. 5a the "sine" curve 54a' is placed radially outermost, while the "sine" curve 56a' is placed in the cam guide device 12a a distance radially within the "sine" curve 54a' S Alternatively the "sine" curve 54a' can be arranged radially within the "sine" curve 56a' (in a manner not shown further).

In each of the cam guide devices 12a and 12b there are designed a corresponding pair of "sine" curves 54a', 56a' in a manner not shown further and each "sine" curve can be provided with one or more "sine" planes as reauired.

In Fic. 1 scnematic reference is made to a cam guide device 12a and !Zb, while the details in the associated "sine" curves and "sine" planes are shown further in Fiq. 9 14.

L; L L The "sine" concept Generally the "sine" concept can be applied with an odd numbered number '1,3,5 etc.) of cylinders, while an even numbered etc.) number of "sine" planes is employed and vice versa.

In a case where there is employed in each of the cam guide devices 12a and 12b a single "sine" plane (having a "sine" top and a "sine" bottom), that is to say the "sine" Diane covers an angular arc of 3600, it is however immacerial whether an odd numbered or even numbered number of cylinders is employed. Correspondingly with a number of two (or more) "sine" planes there can for instance be employed a larger or smaller number of cylinders as reauired.

The said case with a single "sine" plane can be escecially of interest for use in engines running rapidly which are driven at soeeds over 2000 rpm.

According to :he "sine' concept the individual enc:ne can be internally I3 reared with resDec: to speed, all according to which nurmber of "sine" :ops and "sine" bottoms is to be employed at each 350° revolution of the drive shaft. In other words according to the "sine"- concept both engines can be built precisely in the revolutions per minute reaion which is relevant for the individual application.

Generally the series arranged cylinders of the engine, with associated pistons, of the illustrated embodiment are arranged in specific angular positions around the axis of =he drive shaft, for instance with mutually eaual intermediate spaces along the "sine" olane or along the series of "sine" planes the "sine" curve).

For examDle f=r a two cycle or four cycle engine numberina three cylinders (see Fig. there can be employed for each 360° revolution two "sine" tops and two S "sine" bottoms and four oblique surfaces lying between, that is to say two "sine" planes are arranged after each *I JI other in each cam guide device 12a,12b. Consequently in a four cycle motor four cycles can be obtained for each of the two pistons of the three cylinders with each revolution of the drive shaft/cam guide devices and four cycles for each of the two pistons of the three cylnders in a two cycle engine.

Correspondingly for a two cycle engine numbering five cylinders, as is shown in Fig. 9 and 10, there can be employed, for each 3600 revolution, a "sine" curve with two "sine" tops and two "sine" bottoms and four oblique surfaces lying between, that is to say two "sine" planes arranged after each other in each cam guide device 12a,12b, so that in a two cycle engine four cycles are obtained for each of the two pistons of the five cylinders with each revolution.

The support rollers of the pistons are plazed in the illustrated embodiment with equivalently equal angular intermediate spaces, that is to say in equivalent rotary ancular positions alona the "sine" curve, so that they 2 are subjected one a ter the other to equivalent piston movements in eauivalent positions along the respective "sine" clanes.

The engine cower is consequently transferred from the different pistons 44,45 one after the other via the 2 support rollers 53 in the axial direction for the drive shaft 11 via resoeci:ve "sine" curves each with their "sine" -lane, and the drive shaft 11 is thereby subjected to a compulsory rotation about its axis. This occurs by piston rods of the engine being moved parallel 33 to the longitudinal axis of the drive shaft and support rollers of the ciston rods being forcibly rolled off along the "sine" clanes. The engine power is thereby transferred in an axial direction from support rollers or the piston roas co the "sine" planes, which are forcibly rotated together with the drive shaft 11 about its axis.

In other words the transfer of motive power is obtained from an oscillating oiston movement to a rotational Li movmen orthe drive shaft, hemotive power being zransferred. directl7Y restecl:_ve support rollers of :nciscn ros tc "Sine" planes c, thie drive shaft.

7n 7ig. 6a thr I schematically illustrated a =u~oor- roller 53 on- an obliauely extending portion of a 'sne -cur-e 8a. -a~ial driving forces are shown from an associated =iston 44 havinag pistonl rod 48 in the fc= of an~ arrow -F a anrd equi,.alenll in- a radial plane decomposed .rotationai forces zran-rred to the"se -lae8 snown by an arrow:.

The rotational 7orceS can- he deduced from forula 2 rr=Fa. tan q ccordi ng to ceinvention one achieves inter alia byv means of a cartc=l1ar desig~n of the "sine" lane 0 .7T h acccding to thfe i=nenion, thLe expaunsion stroke ofth o~stns 4 ~-ckond agularly relative to the rozatonal arc or tde rive sna-f-: becoming larg~er than :h te compressionl szrcke or the cistons 44,45. in s =i o f ta 'different s-eecds oZ movement of the pistons in :tOsi ite direczf0ns of movement-, arela7tve~y more unliorm rer or ~mo tI~ :4e tthe drve shaftIIcn erz c e ensur-ed and -in addition a 'more uniform", that is to say more vibration-f- r nr of the engine.

7n Fig(. 6 8 -:iere is schematicall1Y shown the mode C_ Cmrz n of a t ree cvl-1 e enCi re 70 C)I Jn which only :n.e one tiJston 441i shown of thte two cooperating pistons 0 *II, -5 a planmar s-pread condition. alon an e* associated "sn"-curve 54' whicnh consists of two Lnutually1 succeeain= 'sine"l t=_anes, plus the associate- 0 mar c-astor 53 o: tne associated one ciston rod 48. in eacnh of teFicures C- 8 there is schematically shown the aSscciace~ one pitn44 in each or- tnhree cylinders 21 of :ne enne, a=n equi-,-alent arrancement being employed for tn."e pistcn 415 at o=poste end of the cylinders. For _he sake orc--: the cylinderZ 21 and the opposite ~RA~ iston45=-ve oee=n omitted from 6t G- a, only the :-stocn its =iston rod 48 and i-s main castor 53 being E E SHT 27 shown. ;Axial movements of the piston 44 are illustrated by an arrow 57, which marks the comfreslon stroke of the -Ciston 44, and an arrow 58, which, marKs the eoanrlon stroke of the 4Stjon 44.

The "1sie j-e cur 54' is shown withaloe rl path 54, which has a double "sine" plane-shiare contour annl wnichn generally guides the movement of the main castor 53i an axlal directiofl, in that it more or less constantly7 effects a dowriward-'Y, directed fore:o the 0 stol 4,4 ra the main castor 53 towards the roll o~ath in the e:=ansicn stroke and an unwardly directed force fom the roll ath 54 vi a the main castor 53 towards the =i-stofl 44 In the compression stroke. The auxiliary castor 5a (not shown further i~n Fig. 6 8) is received with_ a C7 sure fit relative toan umo,.er roll Path 54h, as is shown For i lustrative reasons the Said roll path- 56b is shown vert,:Icaly above the main castor 53 i-n Fg -,SO a oidct the maximum movement of the main Castor ~na xa ietnrelative to the roll path- 5,1.

:n ract~zCw i Ilb the auxiliarY castor 55 which conro.5 ne~osibilityfor movement Of temain castor 3~ ax ia e -iaz V e :o ts rol o II)atzh 54, a s is s ho wn i ai. Sa.

The auxiliar~r ca=stor 55 i41S nric-mally not active, but

W

1 1 conrol mo-vement of the t:iston 44 in an axial cnr e c t c n the nstances the main castor 53 has a 0999909 tendency ra4 :=elf~ .from t-he cam-t:oming roll path 54..Drn oreratzO litin of- the main castor 53 1 an unitenionl mnne reatve tO tne roll path 4 can herebY be a ode- h rol oath- 56 for the au_-lia_castorS s as shown in Fig,.5a.' norma.lly arranged in :-h :~xe fi:spacng rom che associated O-~t a 74=. 6 curve 4' is shown w ith a frtelvel v st-eep and relatively rectilinear ruInn7in! r 7R cur5 prt-on 60 an a su se-ent, more or less arcuate, I 0 ~crmn rans!on portiZon/dead portion 61 anld a s e cond r e I_=t iTeY mo re getL extend~ing, relative-LY A S WEET rectilinearly running curve portion 62 and a subsequent arcuate transition portion/dead portion 63. These curve contours are however not representative in detail of the curve contours which are employed according to the invention, examples of the correct curve contours being shown in more detail in Fig. 12 and 13.

The "sine" curve 54' and the "sine" plane 54 are shown in Fig. 6 8 with two tops 61 and two bottoms 63 and two cairs of curve portions 60,62. In Fig. 6 8 there are illustrated three pistons 44 and their respective main castor 53 hown in equivalent positions along an associated "sine" curve in mutually different, succeeding positions. It is evident from the drawing that the relatively short first curve portions 60 entail that at all times only one main castor 53 will be found on the one short curve cortion and two or roughly two main castors 53 on the two longer curve portions 62. In other words with the illustrated curve contour different forms of curve cortions can be employed for the compression 23 stroke relative no the form of the curve portions for the excansion stroke. Inter alia one can hereby ensure that che two main castors 53 at all times overlap the expansion stroke, while the third main castor 53 forms a part of the comDression stroke. In practice movement of the piston 44 s achieved with relatively greater speeds of movement in ihe axial direction in the compression stroke than in the expansion stroke. In themselves these different speeds of movement do not have a negative influence on the rotational movement of the drive shaft 11. On the contrary it means one is able to observe that more uniform and less vibration-inducinc movements in the engine can be obtained, with such an unsymmetrical design of the curve cortions C0,62 relative to each other.

Further there is obtained an increase of the time which is relatively placed for disposition in the exansion stroke relative to the time which is reserved for the compression stroke.

r O. In a practical construction according to Fig. 6 8 there is chosen in a 180° working sequence an arc length for the expansion stroke of about 105° and an equivalent arc length for the compression stroke of about 750. But actual arc lengths can for instance lie between 11C0 and when the expansion stroke is concerned and equivalently between 70° and 850 when the compression stroke is concerned.

On using for instance a set of three cylinders 21 associated with three pairs of pistons 44,45, as is described above, two tops 61 and two bottoms 63 are employed for each 360' revolution of the drive shaft 11, that is to say two expansion strokes per piston pair 44,45 per revolution.

On using for instance four pairs of pistons there can be correspondingly employed three tops and three bottoms, tha is to say three expansion strokes per piston pair per revolution.

In the embodiment according to Fig. 9 10 there is 4iscussed a five cvlinder enaine with five Dairs of cistons, associated with two tops and two bottoms, that is :o say with two expansion strokes per piston pair per revolution.

Tvoical cam cuide arrangement according to the invention In what follows there will be described with reference to Fig. 9 and 10 in more detail a preferred embodiment of the "sine" concept according to the invention in connection with a five cylinder, two cyclecombustion engine with two associated, mutually differing cam guide curves Sa and 8b, as shown in Fig. 9 and 10 and in Fig. 12 and 13.

In Fig. 14 there is schematically shown a midmost, theoretical cam cuide curve 8c, which shows the volume change of the working chamber K from a minimum, as shown in the combustion chamber K1 in the dead zones 4a and 4b, iAf to a maximum, as shown in the maximum working chamber K in the dead points Oa and Ob (see Fig. 9 10 and 12 14).

AMENDED SHEET 2 .ccording to the invention the curve Sb, as is il~u~rae~ n r~g.12 14, jc shown at the dead point 0-b an nc~eof otaton O 14 in front of the dead toinr 0a of the curv Ea.

SThe ~ietOlOf rotat4I On of the curves Ba and Sb, chat is co say the direction of rotation of the drive shaft is illustrated boy the arrow -7.

7n Fig. 9 and 10 there are schematically illustrated fve cylindCers 21-1, 2'1-2, 21-3, 21-4 and 21-5 and 1 0 Ibelonging tO two associated cu~Tes 8a and two curves 8b, 99shown s-cread in a schematically illustrating manner in one 9*and the same plane. The five cylinders 21-1, 21-2, 21-3, 21-4 and 21-5 are shown in resocectIve angular ositicls 0*with a muual angrular s-oace of 720, that is to say in :s =csit_4ons which are nromydistributed around the axis =1he rot-ary shaft11 7-m T Fig. 12 there s snown a Zirst. cure 8a, which covers an arc length of_ 1800 from a zosition- 00/3600 to a zosi:0n :100. A. co~oni~~ EBa (see Fig. 9) passes oer a 0 -rreszond-ng arc Ienatn of 1800 :crom -tosit.:on 180' oston G0. other words two succeeding curves Ba 9..-oreacn1 -0 revol':ti on of- the drive shaft.

The Curve B a sho-iws in position 00/3600 a fi:rst dead *oo-nt C a. From po0sition 0 to a S.~t 40 there ~s shown s c~ cm-nsition ortion whic-h corresponds to fi-st ar of a= commresslon stroke and from pocsit_ On o ZoSit-On an oziique-ly (upwardlyv) ex7tenc:ing: r _ort.On 2a, wnic,- corresponds to a main part o:hoe ccompression stroke and from nosition 59.20 to a nos- tzon 75' a seacnd tramSizton porticon 3a, which co-rres-oonds zo a :in-4sninc tart of tnhe comrression stroke hrear- fcm thle pjosition 750 to a posi t ion. 850 hre s sownl in ccnnectiQ withIn a second dead point a rectZ~nardead =crt-io2 a, which is shown passing over ar-?c Lengtn oc Cf FromL che Pcs::-_On- 850 to a position 95.81 there is shown a zransitlcn -ortcfl 5a, from the position 05.8' to a Aiviz!QDED SHEET positi on 1600 an obique downwardly extending, rectilinear Dort-ion Ga and from the position !60" to a -position !800 a transizion zortiol 7a. The r-re tortions 5a,6a, 7a :oaemher csnstijtte an extansic.- porlt-ion.

csj-tion 1800 is shownanew dead tontCaan thereafter the cam guide curve conctinues via a second coreson~ngcurv!e Ba, from teposition 1800 to the -tositiJon 36Q0, that iJs to say with two curves Ba which _ogezher exten. over an arc ±e~hof 3600.

7n 7j-. 13 there is shown an equivalent (mirror i4mage) curve contour for the remaining curve 8b, shown with a d~ead point Ob anrd succeed-iing curve -portion lb-7b.

There i4s shown the dead -point Ob in a poSiti4on 3460, p d q 0 9 p .9 *9 9 0 a.

C

0 -trhe curve =to_-oj lb between the -positions 3460 an-Ld te u~e or--ion Zb between the tositions 3' and -the curve tortion 31b bnetween the tposition-S 600 and -V :z 'e -or":o 10.1-b boetween the tos 4-tions 7550 and 9* 9 4* *0 *Oep 9

P.O.

0 te '~re cc-to-. b:etween the roi ins a 0 a nd 101i. SO the cu,=ve ~oton G dn .L46 0 an bet ween the positions 101.3 between the positions 14160 anMd 9* 9.

0@ 9 9

C.

thtLs to say wiztn the-s dead point Ob shown anew The m auide cont~inues W th a corresponding71 cl-Ire Sb 'cetzween 7-*e =.osj7ti:r,. IG'~ anrd 3460 (see Fig. The -irstz Sa k:Fic. 12) ccntrols enn (toiton:00240\and csi (position 205"/25 0 or The second cu: e Sb k 7ig. 1 3) contro l open-,ng (cos1t-jon- 146 0 /26Q =-ri ccslnC (r)os-ition f3050 7, In Fig. 14 there is shown a phase-displacement of 14° between the dead points Oa and Ob, in the illustrated, schematic comarison of the curves 8a and 8b. Curve 8b, as shown by broken lines in Fig. 14, is for comparativAe reasons shown in mirror image form relative to the curve 3a, which for its part is shown in full lines in Fig. 14.

By chain lines there is shown the midmost, theoretical curve 8c, which illustrates a curve contour approximately like or more like a mathematical "sine curve" contour.

In Fig. 9 and 10 there is shown the "sine" plane 8b in a position 14' in front of the position for the "sine" plane 8a. The five said cylinders 21-1, 21-2, 21-3, 21-4 and 21-5 are shown in successive positions relative to the associated "sine" plane and individually in successive working positions, as shown in the following diagram 1 and diacram 2.

_:acram 1 v.ith reference to Fia. 9 and Fia. 12 13.

2 N:>.u.der No. Angle Working Exhaust Scavenging Curve Position Posl:icn Ports Ports Zone 8a/8b 1-1 30/1830 cmnDression closed open* la/lb -2 "'5/255° ccmoression closed closed 4a/4b 21-3 1470/3270 expansion closed closed 6a/7b 1-4 :190/390 compression closed closed 2a/2b 21-5 :91/1010 excansion closed closed 5b/6a The scavenging ports 24 open in position 160°/340 0 and close In position 250/2050, that is to say the scavenging ports 24 are held open over an arc length of The exhaust ports 25 are held on the other hand open over an arc length of 390, that is to say over an arc length which is chase-displaced 14° relative to the arc lencth in which the scavenging ports are open (see Fig.

14) The scavenging ports 24 can consequently be open over an arc length of 20 (see the curve portions la 3a in Si Fig. 12 and the sinale hatched section A' in Fig. 14)

TC

Uoi~ 33 after the exhaust ports 25 are closed. This means that the compression chamber over the last-mentioned arc length of 200 can incer alia be supplied an excess of scavenging air, -hac is to say is overloaded with compressed air.

Diaaram 2 with reference to Fig. 10 and Fig. 12 13.

Cylinder Angle working Exhaust Scavenging Curve No. Position Position Ports Ports Zone 8a/Bb 21- 210/2010 comoression closed closed la/2b 21-2 930/2730 exuansion closed closed 21-3 1650/3450 expansion ooen* oOen 7a/7b 21- 2370/57° compression closed closed 2a/2b 21-5 3090/1290 expansion closed closed 6a/6b W* The exhaust porrs open in position 1460/3260 and close in position 1850/50, that is to say the exhaust ports are open over an arc length of 390° From Fig. 14 iz will be evident from the marked off, individual hatched sections B' that the exhaust ports can be held open over an arc length of 14° before the scavenging ports 24 open.

The said sections A' and B' show the axial dimensions fr :he exhaust ports 25 and the axial dimensions of the scavenging ports 24 in a respective outer portion of the working chamber K. The ports 24 and 25 can thereby be designed of equal height in each end of the working chamber K. The said height is shown in Fig. 12 -14 by X2.

In an angle zone of 5° (from position 750 to position see especially Fig. 13) of the "sine" plane 8b and in an angle zone of 100 (from position 750 to position 85c see especially Fig. 12) of curve 8a, the respective associated piston 44 and 45 is held pushed in to the maximum with a minimum spacing X of for instance 15 mm between the piston head 44a and the middle line of the wor.ing chamber.

With reference to Fig. 12 it must further be observed that over an arc length of 36.6 0 from position 5 9.2 0 to S position 95.8°, the spacing between the piston heads is AIMIENCED SHEET 34 changed relatively little. heszacIng from the piston hiead 44a to the middle line 44'; is changed from a minimum A s1 mm Uin the dead Zor-_ion 750 800) to a 20 mm szacing~) Cor-reszondinrgly hespacing from the piston head. to -;he middle line 44' is chanced from a minimum X is 15mm in the dead norcion 750 800 to a 25 mm s~acinST in psition 570 Fig. 11.

Over said arc lenath of 36.6 0 the volume in the combustion chamber KI is kept. approximately constant .etween the cistons 44,45.

Combined ef-fects of two nhase-dismtlaced "'sing" zolanes From Fig. 14 the contours of the resnective, two IScurves 8a,eb, which are shown schemacicall-y in mirror (9 imagre re'-wie to each ohrwill be evident. Curve 8b i .99shown re-, with a ffull I-Lne, while curve 8b is shown with broken Line, inM mirror maae about a middle axis between ne oszcs 44,45. -Ile curve 8c shows a theoraoa 2 dmosz cure between the curves 8a, Sb. Zt wJi. I e eviden.

-ham mrnmoso Curve Sc a contour-y which li~es more c_,ose~v to a slne curve co=tour th.an thle contIour-s of one urve 8ab idi;vidua,_L. Conseauencly, eveni one acts a rellative-v =.symme::rica_, contour in the curves 99 a, ab muzuall Iy, a -lat~velv syjmetriLcal contour of the midmost curve 8c =-an be achn4eved.

*09 ~~uel is i~etd At the close of-- the Comrression monase in curve zone anrd 3b the fueI Is lintec:ted n a jet with aflwit the rotati'nq scaven&gn curen t and is mi xed/atomised; effecZr!Ve.V ine -otatino= scavenging air current.

7a'~o =-Li tr-arter: 7mmec'4ate±\- after the =nJeC tzon of Fuel -ha- is tO say at7 the close o:oecommression o)hase eIectronica7lv, 51 A4 controlle-d icnitin is n'a in curve zone 3a and 3b.

Provision 'being m-,ade -For e-::ec:t.Jye rotati~on of the gas mixorure s cavenc-ng air fuel ina fuel cloud Past o1' AMi3~iDzo SHEET the ignition arrangement. According to the present invention one can aim with advantage at an ignition delay of 7 10% relative to the conventional ignition angle.

Comoustion phase In the illustrated embodiment the combustion starts immediately after ignition and is accomplished mainly over a limited region in which the pistons roughly occupy a maximum pushed in position, that is to say at the close of che curve zone 3a,3b, that is to say in a region where the oistons are subjected to minimal axial movement. The combustion proceeds mainly or to a significant extent where the pistons 44,45 are held at rest in the inner dead oortion 4a and 4b, that is to say over an arc length of and 5° rescectively. However the combustion continues as recuired a greater or smaller degree in the following -ransition -ortion 5a,5b and in the main expansion portion 5a,6b, depending upon the speed of rotation of the rotary shaft. As a consequence of the rotating fuel cloud in the =comustion chamber 1l in the dead portion 4a,4b and in -hat one can keep the flame front relatively short in t:e disc-shaced combustion chamber Kl, there can be ensurea in all instances fuel ignition for a main bulk of the fuel cloud in the combustion chamber Kl, that is to say within said dead ortion 4a,4b. In practice the combustion 2I chamber can be allowed to be expanded to the portion lust outside the dead portion 4a,4b with largely corresponding advantages in a defined volume of the working chamber K.

Soeed of rcmbusticn The speed of combustion is as known of an order of maanitude of 20 3 meters per second. 3y the application of a double set of fuel nozzles and a corresponding double set of ign=iion arrangements distributed over each quarter of the peripheral angle of the working chamber (see Fig.

4b) the combustion area can be effectively covered over N the whole of the disc-shaped combustion chamber K1. In -1.L -1L practice especially favourable combustion can thereby be achieved with relatively short flame lengths.

ODtimal combustion temDerature: As a result of the concentrated ignition/combustion zone 3a,3b which is defined in the chamber K just 2_ front of the combustion chamber K1 and the region immediately after the combustion chamber KI, that is to say in a coherent region 3a 5a and 3b 5b, where the pistons 44,45 are at rest or largely at rest, it is possible to increase the combustion temperature from usually about 1800 0 C to 3000 0 C. It is possible thereby to achieve an optimal (almost 100%) combustion of the fuel cloud even before the pistons 44,45 have commenced fully the expansion stroke, that is to say at the end of the urve portions Teramic ring Provision is made for a ceramic ring, that is to say a ceramic coating applied in an annular zone of the .or.ing chamber K corresponding to a combustion region (3a 2D 5a,3b,5b), so hat high temperatures can be employed escecialv in the comoustion chamber Kl, but also in the ollowing portion Sa,5b of the combustion region. The ceramic ring which is shown with a dimension as indicated by a broken line 70 in Fig. 12 14, comprises the whole combustion chamber K1 and is in addition extended further cutwards in the combustion chamber over a distance 13.

Introductory Excansion Stroke After at least considerable portions of the fuel are consumed in the afore-mentioned combustion region (3a 5a, 3b,5b) and one has just started the expansion stroke there are aenerallv optimal motive forces. More specifically this means that by way of the cam guide along :he curves Sa and Sb there is obtained an optimal driving moment immediately the exoansion stroke commences in the transition region 5a,5b and increases towards a maximum in the transition region 5a,5b. The driving moment is AN i ,maintained largely constant in the continuation of the AMENDED SHEET r expansion stroke (in the region 6a,6b) and at least in the beginning of this region, as a consequence of possible after burn of fuel in this region in spite of the volumetric expansion which occurs gradually in the chamber K as the expansion stroke croceeds forward through This.

Expansion Phase According to the illustrated embodiment the compression phase takes place relative to the curves 8a,Sb under angles of inclination of between about 250 and about 36° in the respective two curves 8a and 8b, that is to say with a mean angle (see Fig. 14) of about 30°. If desired the angles of inclination (and the mean angle) can for instance be increased to about 450 or more as required. The expansion phase takes place correspondingly in the illustrated embodiment at between about 22' and 270 in the two curves 3a and Eb, that is to say while at a mean angle see Fig. 14) of about 24°.

As a result of the relatively steep (mean) curve contour cf 30° in the compression phase and the relatively 2 =enter czzr.our In the expansion phase, there is achieved a carticlar y favourable increase of the durability in time cf the expansion stroke relative to the durability of the compression stroke.

According to -he invention one can by means of said unsymmetrical relationship between the speed of movement in the compression stroke and the speed of movement in tme expansion stroke, dislDace the start of the combustion process in the comoression phase closer up to the inner dead point and thereby time-displace a larger part of the combustion process to the beginning of the expansion chase, without this having negative consequences for the combustion. Conseauently there can be achieved a better control and a more effective utilisation of the motive force of the fuel 2cmbustion in the expansion phase than hitherto. Inter alia there can be displaced an otherwise S ossibly occurring, uncontrolled combustion from the compression phase over the dead point to the expansion

C

PA T A AMENDED

SHEET

38 ohase and thereby convert such pressure points", which involve uncontrolled combustion in the compression phase, to useful work in the expansion phase.

By extending the expansion phase at the expens of the compression phase a relatively higher piston movement is obtained in the compression phase than in the expansion chase. This has an influence on each set of pistons of the combustion engine in every single working cycle.

Rotation effect in :he working chamber There is established rotation of the gases in the working chamber by ejecting exhaust gases via obliquely disposed exhaust ports 25 (see Fig. 2) followed by the iniection of scavenging air via the obliquely disposed scavenging air ports 24 (see Fig. There is set up :hereby a rotating, that is to say helical gas flow path (see arrow 38 in cylinder 21 -1 in Fig. 9) which is maintained over the whole working cycle. The rotational effect is reactivated in the course of the working cycle, 0 cnha is co say during the injection, ignition and combustion phases.

There is conseauently supplied a new rotational effect to the gas flow 38 during transit in the working cycle by fuel injection via the nozzle 36 and subsequent fuel ignition via the ignition arrangement 39, the attendant zombusticn producing a direction fixed flame front with an associated pressure wave front roughly coinciding with the gas flow 38 already established. The rotational effect is consequently maintained during the whole compression stroke and is reactivated during transit by injectng fuel -:ia an obliquely disposed nozzle jet 37, as shown in Fig. via a corresponding obliquely disposed nozzle mouth 36. Additional rotational effects are obtained in the combustion phase.

A still additional increase of the rotational effect can be obtained according to the construction as shown in Fig. 4b by the application of an extra (second) fuel L, D E D SHEI ft e nozzle 37a, whc is disposed angularly di solaced relati4ve the -first f uel nozzle 37, amd by the application Of al" extra igni tjon arrangrement 39a, which iLs disposed angcUlarly displaced relative rto the first: Jicnitiorn arrangement 39. When the exhauslt =oors 25 open again, On the terinationl of. working -c-le, the exhaust Z-as Is exhaustea with a high speed Of movement, that is to say with a high rotational speed, duringz exhaustion of exhaust Clas via the said obliauelY disposed exhaust ports. Further :0 the rotational effect for the exhaust cases is maintaime.

.immediate.Ly the ob-I-qely disposed scavenging ports 24 0*Cm oe.n, So tnaz tn residlues ofL the exhaust gases are 4....scavenged with.- a rotational effect Outwardly from the worKIMng ch1amber K at the close of the e~ansio= phase a.7-r the hbe(=jr~inq of t-he compression phase. Thereafter the roatonleffect. -S MaiM7taJned, after closina of the ehaust,-t the scavenging -ports being Continued 'to b held ooen! over a s-LamficanTt arc, lenc~rth.

ReaatO teC=mreSSilo rZ 4 o of he enaime rln ~ccorningto th.:e inMventi~n itIS =oss-bet rg t ~the volume b:etween =istons 44,,15 of the cvll-nder 21 by recul atn th uulspacing between the pCistons 44,45.

7, s herebv possi--le to directlyv recplate the compression.

rat~ Z tM cyinv 21 as reciired, for instzance durg .4 Onerati on of thincn y means ofa0:l eulto Z e CrzI C anated ing to the "1s ine" -concemrt.

44*t ~s soeC~-".Vnerstn according to thre znvntin t chngee compressjon ratio.; jn coninectionl withi 7-rncu :ne engine, :nat is to say or, cold starrelt~e t amost faoraO2C ooession ratio ZpOSSIb ou~n uua oerat:jzn. B'ut it: can also be o-f _Jerest 7t= 'nanCre tne com-pressIon ratr-'o aurinc trt~ o a~U R A other ScCnst:r uc:4== solut:ln- Zor such a reaulatiOnl a acordina to te;vnif sbased on pressulre 0Gil controlled e :eu.tn enIu.Atralev there can conzrSHEET A~EDD HE be emloyed for instance electron ically-controlled regulating r4ue, ino s not shown Further herein, for recu'a~inO-I the comnressioni ratio.

Alte~a~ve'/ -here can be employed a corresponding regulat~ncz :OSility also for the piston 45 by replacing the cam guide device 12a with a cam guide device 0 .orresnondingly as shown for the cam guide device 12b.

7t is at=raren7t according to the invention that it is -mossihle to recnatae the position of both pistons 44,45 in associated cylinder via their resmective cam guide arranenl with their respective separate possibilitV of rerul atiJon, ina mu:ually needet mann.

tis also aptarenz that theregulation o-ff the *OO zoiton c: the -pistz-ns in the cylinder can be effec .z.ed C.5 svncnrno5 to oe two 'OstOc 44,45 or individually as C..nc sI -f r Z_- 15and !6 there is shown solnemat4Cally a-, alternative sltoofcertain details in a camgud devi ce, as t s rezerred to herein by the reference P0numeral 177a, and. coz an associated -iszon rod, as shown by ne eferncenimer-= 14 as well as a pair of nressure C..soneres, as shown by- the raffrence numerals 153 and 155.

7h cam =La:ie ev ,-ce !12a: CCC. z ne constructi -on accordin to Fig. 1 the cam guide device 12a -4s shown having a relatively space-demanding desi-oi w_ t' a=ssoci-Mted casters 53 and 55 arranaed at the s~ne r eacnot'er direction of the camn g uicde device 12a na s z5o sa-,v' with-- the one caster 53 rrnd Ll~ cusi e a mair g caster 55 and with t-he associated Tsi-inel grooves 54,55c illustrated correSoontncICv ra IlV sezarated on each of their radial :n healzernative constructz7ion accordiet i.1 and 16 teCam cu-lie device -112a is shown with associated 7ressure son'_eres 73 55 arranged I n succession in the !~\axial direczion c: t he cam guide device 112a, that is to say with_- asphee on, eacr. res-mective side of an indivi- C)EDE SHEET e, S9 6 4 6~ 9 a a 0 *06 9 @0 *a 9 9

S

.9 0 dual, common nrojecticn, illustrated in the form of an i-trmediaze annular flange 112. The annul ar flange 112 4 s shown with an upoer "sine" cu-ve ]=orMiJng "sine' c~roove 154 ]for auitinoz an _:pper pressure sphere 1_3, which Forms the main sumnort sphere of the ciston -rod 148, and a lower siet, cur-,e forming "sine" groove !55a for guiding a lower pressure sphere 153, which forms the auxiliarv su==Ort sphere of tens piston rod 148. The grooves 154 and 155a have, as shown in Fig. 157, a laterally concavely rounded form corresponding to the spneri cal contour of the szheres i-53,75. The annular f lance 112 41s snown having a relatively r~a11thickn5ss, but the small thick-nes s can b:e comtmensated for as to strength 4i that the annular flange 112 has in the periopheral di-ection a sef-einoan 13 "ine u~econtour, such as inodicated by the oblJcrely extending section of the annul~ar f lanne illustrated in.

16.:n Fig. 153 the annular ]fflange 2.22 is shown seamentaIv in= sect-on, while in- Ficr. !G there is shown in oross-sect-'on a cer'onerally locally defiLned s eaent of -h te a-znular f~ance L.12, seen from the i-nner sid~e of the aninular fi",ae There can be e=-!oved a largely corresponding design of-' the adr-et±nc etails in both cam guide devices, enat is to say also Ji the cam =uicde device not shown frther ccrresucontin= to the lower cam auide devi ce according= to Fig. 1.

The ncisc ro:d 148: Accodingto Fig. a pine-shazed, relatively volIum inous z.ist7-on rod 48 _4s shown, ,h i> 1n t he alenaie ewcoa±nent accordin-g to _Fig. !15 and 16 there ilstrteda =I±mmer, comoact, rot-shaped pistoro 28 haavin= aC-shaped head portion 1.48a witn two mutually_ ontosite Sonhere hcolders 2.48b,248c for a respeczilve =ressure sohr The npiston rot. 2.48 can -n a manner not shown futhe be Crovited with external screw threads which cooperate w::nh Intern:al screw threads in the head portion, so ta 0 a a.

0' 0*SO a..

COOS

S

9 9 a.

90 9 0@ Ik.3~E P 42 the piston rod and thereby the associated sphere holder 148b can be adjusted into desired axial positions relative to the head portion 148a. This can inter alia facilitate =he mountina of the sphere holder 148b and its associated sohere 153 relative to the annular flange 112.

In Fig. 16 the annular flange 112 is shown with a minimum thickness at obliquely extending portions of the annular flange, while the annular flange 112 can have in a manner not shown further a greater thickness at the peaks and vallevs of the "sine" -curve, so that a uniform or largely uniform distance can be ensured between the spheres 153,154 along the whole periphery of the annular flange.

By the reference numeral 100 there is referred to herein a lubricating oil intake, which internally in the C-shaoed head portion 148a branches off into a first duct 101 to a lubricating oil outlet 102 in the upper sphere holder 148b and into a second duct 103 to a lubricating oil outlet 104 in the lower sphere holder 148c.

:he cressure scheres 153,155 :nstead of -he casters 53,55 shown according to Fig.

which are mounted in ball bearings, pressure spheres 153,155 are shown according to Fig. 15 and 16. The crsssure spheres 153,155 are mainly adapted to be rolled relatively rectilinearly along the associated "sine" grooves 154,155a, but can in addition be permitted to be rolled sideways to a certain degree in the respective groove as required. The spheres 153 and 155 are designed identically, so that the sphere holders 148a,148b and their associated sphere beds can also be designed mutually identically and so that the "sine" curves 154,155a can also be designed mutually identically.

The cressure spheres 153,155 are shown hollow and shell-shaped wich a relatively low wall thickness. There /3 are obtained hereby pressure spheres of low weight and small volume, and in addition there is achieved a certain Az,:E: D SHEET 43 elasticitv in the sohere for locally relieving extreme pressure forces which arise in the sphere )er se.

In Fi'a. 77 and 18 a pDair of auide rods 105,106 are shown which pass zthrougrh internal guide grooves 107,108 along opposite sides of the head porzion 148a of tlb: piston rod 148.

HIC SEE T

Claims (9)

1. Arrangement in a combustion engine (10) having internal combustion, comprising a number of engine cylinders which are arranged in an annular series around a common middle drive shaft (11) and which have cylinder axes running parallel to the drive shaft, each cylinder including a pair of pistons (44,45) movable towards and away from each other and a common, inter- mediate working chamber for each pair of pistons, while each piston (44,45) is equipped with its respective axially movable piston rod (48,49), the free outer end of which forms via a support roller (53) support against its respective curve-shaped, that is to say "sine" curve shaped, cam guide device (12a,12b), which is arranged at each of opposite ends of the cylinder (21) and which controls movements of the piston relative to the associated cylinder, characterised in that at least the one (44) of the two pistons (44,45) in each cylinder is regulatably adjustable axially in the cylinder for regulating the relative spacing between the pistons, especially for regulating the compression ratio i) in the common working chamber between the pistons.

2. Arrangement in accordance with claim 1, characterised in that the position of the piston (44,45) in the cylinder (21) is adapted to be determined via the associated cam guide device (12a,12b) of the piston by means of a separately regulatable control arrangement (13b).

3. Arrangement in accordance with claim 2, characterised in that the said one cam guide device (12b) is axially displaceable along the drive shaft (11) in a sliding abutment on this, and is adjustable within a limited WO 98/49436 PCT/NO98/00126 length of the drive shaft (11) by means of said separately regulatable control arrangement (13b).

4. Arrangement in accordance with claim 3, characterised in that the control arrangement (13b) is regulatable by means of pressure oil.

Arrangement in accordance with claim 4, characterised in that the control arrangement comprises an annular pressure oil chamber (13b), which is defined between the drive shaft (11) and the cam guide device (12b), and a piston- forming compression simulator which projects from the cam guide device (12b) radially inwardly into the pressure oil chamber (13a) and partitions this into two part-chambers, that is to say one on each side of the compression simulator, the part-chambers communicating with their respective, mutually adapted pressure oil circuits.

6. Arrangement in accordance with one of the claims 1 5, characterised in that the cam guide device (12b) is fast connected for rotation with the drive shaft (11), the compression simulator (12b') being passed through parallel to the axis of the drive shaft (11) by a set of driving bolts which allow a certain axial movement of the compression simulator (12b') relative to the drive shaft (11), while the driving bolts are connected at their respective opposite ends to the drive shaft (11) and connected to a carrying member (13) fastened to the drive shaft (11).

7. Arrangement in accordance with claim 6, characterised in that the drive shaft (11) is axially extended at its outer end with a radially graduated end portion, which is WO 98/49436 PCT/N098/00126 46 rigidly connected to the carrying member (13) in the form of a cup-shaped end part, the pressure oil chamber (13b) being localised between the drive shaft (11) and the cup-shaped carrying member (13).

8. Arrangement in accordance with claim 6 or 7, characterised in that an oil guide means which projects axially through an axial bore in the cup-shaped carrier member (13) and further inwardly into an axial bore in the drive shaft (11) aligned with that is provided with a pair of internal, axially extending pressure oil ducts (14a,14b), which empty radially outwards into their respective associated pressure oil rings (14a',14b') which communi- cate with a pressure oil duct (llf,llg) to respective part-chambers of the pressure oil chamber (13b).

9. Arrangement in accordance with one of the claims 1 8, characterised in that one piston (44) of the cylinder which is in question to regulate the position of in the associated cylinder, constitutes a piston which controls opening and closing of exhaust ports (24) of the cylinder.