WO1998003794A1

WO1998003794A1 - Rotary assembly

Info

Publication number: WO1998003794A1
Application number: PCT/HU1997/000039
Authority: WO
Inventors: Ferenc ADORJÁN
Original assignee: Adorjan Ferenc
Priority date: 1996-07-19
Filing date: 1997-07-17
Publication date: 1998-01-29
Also published as: HUP9601972A2; HUP9601972A3; HU9601972D0; AU3631397A

Abstract

A rotary assembly consisting of a housing (10) with a cavity (13a) that is bounded by the first and the second planar walls (11, 12) as well as by a curved, closed surface (13) in-between, with inlet (14) and outlet (15) openings connecting to the cavity, the rotatably mounted shaft (20) with an axis perpendicular to the planes of planar walls is furnished by a slot (22), parallel and symmetrical to the axis of the shaft and limited within the section of the shaft inside the parallel walls of the cavity and with one or more vanes (30) fitted into the slot which divide the cavity into two or more sub-sections. The inventive idea will be carried out by means of the following technical measure. The end surfaces (31, 32) of the vane (vanes) toward the curved surface (13) of the cavity are defined by rounded curves in cross section parallel to the planar walls of the cavity, while in any such cross section the curved surface (13) of the cavity follows a non-circular curve, having a primary internal fitting point which lies on the rotational axis (21) of the shaft (20) and this non-circular curve is determined such a way that the rounded end surfaces (31, 32) of the vane (30) are in fluid-tight contact along two opposite generatrices (13c, 13d) with the curved surface of the cavity regardless the angular position of the shaft, the shaft and the internal curved surface of the cavity are also in a permanent fluid-tight contact at least along a single fixed generatrix (13e) or a range of generatrices of the curved surface; while the inlet (14) and the outlet (15) openings are on the two sides of this contact range (13e).

Description

Rotary assembly

The different types of sliding vane rotary pumps used foi liquid or gaseous substances, as well as die oil-sealed vacuum pumps have been widely applied and lather well known foi long tune Typically, they aie built with internal cavities bounded b\ cylindπcal and pianai sui faces and then shaft is positioned eccentπcally The vanes that aie fitted into appiopπate slots of the shaft are forced to touch die cylindπcal surface of the cavity by using springs or by centπfugal foice The traditional such assembhes share the disadvantages that a substantial friction aπses along die contact hues of die vanes with the internal surface of the cavity, while causing direct limitation on die head (pressure drop) of die pump In case of the pumps with vanes positioned

by centπfugal force, a minimum rotational speed is also lequned befoie the pump would woik

A further limitation for such pumps (or hydraulic motors) is that in case of opeiating with mcompiessible fluids the volume m the slots of the shaft between 01 behmd the vanes (spπng space) changes during the operation of the assembly which requues passageways 01 loose fitting of the vanes into the slots, which deteπorates die volumetπc efficιenc^* All such kind of pumps generate a oie or less oscillating fluid flow diat oscillation can onh be lowered by inci easing the number of vanes that causes friction penalty

Some of the above descπbed disadvantages aie ehmuiated by construction descnbed in die US patent No 5.006.0 '^•i 3 The essence of this is diat the cioss section of the internal curved surface of the pump cavity follows a given function (in fact the Pascal s limacon cun e with the eccentricity parameter of 0,5) and there is a single vane dirough the slot of the .shaft. The main limitation of this coustmction is that the proposed surface geometry does not ensure the exact continuous contact between both ends of die vane and the curved surface, unless the vane is iiifiiiitely thin. The oscillation of the pump flow is not eliminated at all. These conditions pose

serious limitations for the applicability of such pumps (e.g. for precision applications).

There exists at least one known proposal to apply the eccentric rotary assembly with sliding vanes as an internal combustion engine: e. g. the equipment as described in the US patent No. 4,909,208. This coustmction. however, has die potential shortcomings both from point of view of increased friction due to the spring supported vanes and from difficulties in sealing the combustion chamber. These problems are anticipated, since the sudden pressure peak following the ignition could push the vane easily into the slot, creating a free escape gap for the hot gases, unless the vane springs are extremely stiff.

The current invention is aiming at eliminating the above described shortcomings of the known sliding vane rotaiy assembhes by introducing such a general geometrical solution that ensures the reliable close contact between the vane and the internal surface of the cavity regardless of die rotational speed and widiout creating substantial friction forces. Under some special conditions die proposed equipment produces (or in case of a hydraulic motor, it requires) oscillation free fluid flow with constant rotational speed of its shaft. When he proposed arrangement is applied as die compression and expansion units of an internal combustion engine,

the resulted equipment is free from many difficulties that arise in case of the formerly proposed rotary combustion engines.

The solution proposed in the cuπent invention is based on the geometrical discernment that the locus of die endpoints of a straight section which rotates 180 degrees in the plane around a fixed pomt such a way diat said pomt stays on die section widiout bemg fixed to any given point of the section, obviously exists and can easily be created Any plane curve that has been

deπved such a way s aie die common featuie that at least one of the cords m any given direction wluch go tluough the selected fixed pomt (die coid centre) has the same length as the onginal section (Note that foi convex curves - and only diose aie relevant from the pomt of view of the invention - dieie is only one single coid of die curve in any direction ) Later on, we

will refei the curves that belong to this very generally defined plane curve family as equicord curves Thus, die / (φ) functional form of such curves m (/ ,φ) polai co-ordmates centred at the

coid centie. satisfy the equation

r(φ) = 2c - r(φ + π)

wheie 2c is the length of the coids which he on the coid centre (the angle is measured m ladians) It is obvious that any of such closed curves can freely be defined within an angle range of φ e[0,Λ"] and die ot ei half of the curve comes fiom the above equation This option allows

extie ely high fieedom in ci eating specific forms of such curves A great vaπety of different plane curves, even curve families satisfy the above equicoid condition, from among diose the best known is the Pascal's hmacon curve (with some lestπctious on its paiameters)

The above outlined geometπcal featuies of the equicord curves got matenahsation m the ventiou by discerning that a single, πgid vane can only touch by bodi of its rounded ends the internal curved suiface of the assembly cavity - legardless of its angular position - if the cross section of the cavity is deπved from an equicoid curve and the totational axis goes through the equicoid point It can be proven that if in cioss section perpendicular to the rotational axis the ends of the vane follow cuculai convex aics then the cioss section of die required shape of die cavity has to coπespoud to the outei paiallel of an equicoid curve at the distance of the rounding radius of the vane. We obtained such a way a generic geometry for a rotary assembly, assuming appropriate shaft geometry.

Corresponding to the objectives of the invention, the rotary assembly - consisting of a housing with a cavity that is bounded by the first and die second planar walls, as well as by a

curved, closed surface in-between, with inlet and outlet openings connecting to the cavity, the rotatably mounted shaft with an axis perpendicular to the planes of planar walls, fiirnished by a slot parallel and symmetrical to the axis of the shaft and limited to die section of die shaft inside the parallel walls of the cavity; with one or more vanes fitted into the slot which divide the cavity into two or more sub-sections, - is designed such a way that the end surfaces of the vane (vanes) toward the curved surface of the cavity follow rounded curves in cross section parallel to die pianai walls of the cavity, while in any such cross section of die curved surface of the cavity follows a non-circular curve, having a primary internal fitting point which lies on die rotational axis of the shaft and this non-circular cui"ve is deteπnined such a way that die rounded end surfaces of the vane are in fluid-tight contact along two opposite generatrices with the curved surface of the cavity regardless the angular position of the shaft; the shaft and the internal curved surface of the cavity are also in a permanent fluid-tight contact at least along a single fixed generatrix or a range of generatrices of the curved surface; while the inlet and die outlet openings are on the two sides of this contact range.

A preferred embodiment of the rotary assembly is characterised by identical circularly

rounded end surfaces of the vane and the cross section of the curved surface of the cavity follows a geometrical curve which is an outer parallel of an equicord curve (.satisfying the

equation r(φ)=2c-r(φ-π) in polar co-ordinate system centred at the primary fitting point of me

curve) at the distance of the rounding radius of the vane. It is also a piefeπed case when the vane is a sohd, single piece component

In some othei pieferred embodiments of the rotary assembly there are at least two

separate cavities neai to each othei widi separate vanes m them (twin cavity arrangement).

In case of a piefeπed twin cavity arrangement the vanes aie fitted mto die slots of the same shaft that tiaveises both cavities

A fuithei twin cavity aπangemeut is chaiacteπsed with identical cavities, with vanes in diem peipeiidiculai to each othei in piojectiou to a plane peipendiculai to the shaft axis and the mlets of the cavities divide fiom a common inlet, as well as the outlets of the cavities meige mto a common outlet

In case of anothei piefeπed dual cavity anangement the outlet of the first cavity m its housmg is connected to the inlet of the second cavity and theie is a movable valve body in the connecting channel that opeiates m a synchionised way with the single shaft or the shafts that

encompass the sliding vanes, and theie exists - piefeiabh at one side of the valve - a fuel injection nozzle and an igniting equipment

The invention exhibits seveial advantageous featuies Peihaps the most significant such featui e is that it is possible to ci eate a pump from it that is applicable foi carrying gaseous, hquid or mixed fluids and which is chaiacteπsed by high volumetπc efficiency, high head, low energy loss tlirough friction between the cavity wall and the vane, which not only improves its energy efficiency but also mci eases the lifetime of the assembly The same 01 a similar assembly can also be applied as a hydiauhc motor having analogous beneficial quahties

It is a geneial advantageous pecuhaπty of the invention that the constraints on the shape of the curved sui face of the cavity allow extiemely high vaπabihty and contmuous parametei adjustment that opens a broad range of options for the designers to optimise the equipment to satisfy a wide range of specific requirements.

It is of high significance that in case of the dual cavity arrangement with perpendicular

vanes, the sum of the volumetric flow rate of the two chambers will be constant (oscillation free) if the shape of the internal cavities are deteraiined suitably. This is a characteristic case of satisfying an extra condition by designing the shape of the internal cavity. When such an assembly is used in hydraulic motor mode with mcompressible fluid then it will also create

constant torque at any angular position of the shaft.

The lack of oscillation in the flow rate together with the high volumetric efficiency opens a new. wide rauge of applicability ranging fiom precision measuring and analytical equipment to hydraulic transmissions.

By adding appropriate auxiliary devices to it, such as fuel injection and ignition devices, it is possible to create a rotary internal combustion enguie which could presumabl be tuned to produce extraordinary efficiency with a wide rauge of different fuels.

It is an additional remarkable advantage of the invention diat it consists of a small number of parts which can be manufactured and assembled by using commonly applied

technology.

It is further notable advantage that by combining several such assembhes into a hydrauhc or pneumatic circuit many useful applications can be obtained, such as multistage torque converter, differential driving mechanism etc. In many of such combinations there is no need for expensive additional equipment (e.g. clutch), it shows, however, remarkable improvements in comparison to the traditional solutions. In the followings the mvention wdl be descπbed by usmg figures that present explanatory sketches and sketches of different pieferred embodiments The brief description of figures is

Figure 1 Side view cioss section of a basic arrangement of the rotary assembly

Figure 2 Sketch of a possible geometry for deriving the cross section of the

shape of die internal cavity Figure 3 I he geometiy of the touching pomt between the cavity surface and the lounded end surfaces of die vane Figure 4 Section view of die oscillation free pump or hydrauhc motor

(coπesponds to die IN-IV plane as shown m Fig ) Figure 5 Section coπespondmg to N-V plane in Fig 4

Figure 6 Hydiauhc driving cucuit built fiom oscillation free pump and hydrauhc motoi m active state Figure 7 The same cucuit as m Fig 6 m neutial state

Figuie 8 Hydiauhc diffeiential driving

Figure 9 Scheme of a multistage toique converter budt from oscillation free assemblies Figure 10 Internal combustion engine built from two rotary assembhes m the moment of valve opening Figure 11 The same engine m the moment of valve closmg

Fig 1 shows a generic aπangement of the rotary assembly with its housmg 10, its first pianai wall 1 1 and its specially curved surface 13 enclosing the cavity 13a The inlet 14 and the outlet I S openings aie connecting to the cavity 13a The position of die shaft 20 within the cavity 13a of the housmg 10 is well shown The slot 22 traversmg the shaft 20 holds the (m this

typical case smgle piece) vane 30 havmg the lounded end surfaces 31,32 The rotary shaft 20 is connected to the planar walls 1 1.12 of the housing 10 by appropriate bearing such a way that the projection of the primary fitting points of die curved surface of the housing should fall onto the

rotational axis 21 of the shaft.

As it can be observed in Fig. 1, the surface of the shaft 20 and the curved surface 13 of die housing 10 has connecting generatrices at the point 13e. Along these generatrices which are

parallel to the rotational axis 21 of the shaft 20 the two surfaces are in fluid tight contact. The same fluid tight contact is maintained at the points 13c and 13d where die generatrices of the rounded end surfaces 3 1.32 of the vane 30 and the curved surface 13 of the housing 10 are in contact. The inlet 14 and the outlet 15 are always separated fiom each other by at least one of

the generatrices 1 c and 13d during the rotation of the shaft 20.

It is also clear form Fig. 1 diat die inlet 14 and the outlet 15 openings are situated on the two sides of the connecting generatrix 13e of the surface 13 and the surface of the shaft 20. The inlet 14 and the outlet 15 openings extend down to the zenith 13f and nadir 13g generatrices of die curved surface 13. respectively. These generatrices are defined by the touching lines between the vane 30 and the surface 1 when the vane 30 is in upright position (perpendicular to the plain deteπnined by the axis 1 and generatrix 13e). Should die inlet 14 and the outlet openings extend further than the generatrices 13f and 13g, die full separation of the input and the output

volumes could not be maintained.

It is necessaiy to note here that when the assembly is designed for using with incompressible fluid the extension of the inlet 14 and outlet 15 openings to die zenith 13f and the nadir 13g generatrices is a necessaiy requirement. The inlet 14 and outlet 1 openings have to be created such a way that the curved surface 13 of the housing 10 should go continuously around die openings to control the motion of the vane while the shaft 20 rotates around. The inlet 14 and outlet 15 openings can be designed partially or fully on the planar walls 1 1,12 of the housing by taking into account die above described limitations.

During the pump operational mode of die assembly shown in Fig. 1. the shaft 20 rotates

in the direction as indicated by the arrow and the vane 30 rotates with it while its rounded end surfaces 31,32 follow the curved surface 13 of the cavity 13a of the housing 10. At the moment when die end surface 31 of the vane 30 reaches the generatrix 13e of the 13 surface, die space above die vane is in connection with the volumes linked to the inlet opening 14 (suction or low

pressure side); while the space below the vane 30 is in connection widi the volumes linked to die outlet opening 15 (high pressure side). The two sides are separated by the section of the vane 30 outside die slot 21 of the shaft 20 in the direction of the end surface 32, as well as the connecting generatrix 13d. Later on but until the vane 30 would reach the upright (90 degree) position die

separating surfaces remain the same, since the connection between the rounded surface 31 of the vane at the generatrix 13c is broken, assuming that the inlet opening extends from the generatrix 13e to the zenith hue 13f. During this phase the volume of the suction side increases and the volume of the high pressure side decreases continuously. At the moment when the vane 30

reaches the upright position, when the end surface 1 touches the surface 13 along the zenith generatrix 13f, the volume on the right side of the vane 30 is cut away from the suction side and for a moment there is a confined volume between the generatrices 13f and 13g. As the shaft 20 rotates further the confined volume will be connected to the high pressure side (assuming that the outlet opening 1 extends to the generatrix 13g) and die role of separation is taken over by the generatrix 13c and the end section of the vane 30 toward its end surface 31. As the vane moves the suction side expands further continuously and die formerly confined volume on the right side of the vane 30 is being displaced continuously toward the high pressure side. During a full rotation of the shaft 20. the above process takes place two times. Fig 2 piesents a geometrical sketch of the cross section of the internals of the assembly

(perpendiculai to the lotatioual axis of the shaft) showing as the symmetry ue 30a of the vane

30, which goes tluough the primary fitting pomt "O", and as die arched contoui lines 31 and 32 of the vane are m contact with the 13b bounding curve (corresponding to the surface 13 m Fig

1 ) on the opposite sides of point "O", legardless the angular position of the vane The thin curve

133 is the equicoid cuι^*ve fiom which the bounding curve 13b has been deπved The actual shape of the cui"ves coπespoud to the shape of the cavity of the twin aπangement designed to piovide constant flow, as described below

Fig 3 shows in an eulaiged scale how the bounding curve 13b can be derived from the equicoid curve 133 when the end surfaces 31,32 of the vane 30 are circular arches in cross section with ladius R This deπvation is necessaiy. since the equicoid curve 133 could secure the exact connection between the vane and the curved surface of the cavity only if the thickness of die vane is zeio Thus, taking mto account the leal measuies of the vane 30 we need to substitute die original curve 133 by die outei paiallel curve at the distance of R An arbitrary pomt of this paiallel can be obtained (as it is well known) rf we take the outer normal vector of the point "E^" of the onginal curve and measure the distance "R" to it, obtaining pomt "X" These points geneiate die bounding curve 13b Note diat if the symmetry hue 30.ι of the cross section of the vane goes tluough pomt "E" then the touchiug pomt between die cross section of the lounded end surface of the vane and the bounding curve 13b is at "X" If the rounding of the end surfaces of the vane 30 aie non-cucular oi non -symmetric then the deπvation of the bounding curve fiom the equicoid curve is still possible but diffeient and more complicated

Figuies 4 and 5 pieseut a lotary assembly havmg two internal cavities 13a and 131a

within its housmg 10. which aie identical in shape and size In dns twin or dual construction the

vane 30 in the cavity 13a and the vane 301 in the cavity 13 1a aie also identical and they are fitted into the slots of the same shaft 20. It is important that in perpendicular projection in the

direction of the rotational axis 21 of the shaft 20 die angle α between the two vanes 30, 301 is

90 degree. At this variant of the assembly the inlet 16 of the assembly is connected to bodi of the

cavities 13a and 131a through die openings 14 and the exit openings 15 of the cavities 13a and

131a merge into the common outlet 17.

Since this arrangement is mostly useful when it operates with some incompressible fluid the inlet openings 14 and the outlet openings 15 should extend fiom die vicinity of the generatrix

13e up to the zenith 13f and down to the nadir 13g generatrices, respectively. The inlet 14 and the outlet 1 openings of the cavities 13a and 13 1 a may extend partly or fully over the planar walls 1 1.12 and 12a of die cavities assuming that they do not exteud over die plain determined by the zenith 13f and the nadir 13g generatrices.

It is of high importance that the curved surfaces of the cavities of the twin assembly can be chosen such a way that when the assembly is applied as a pump with some incompressible fluid, then the volume of the displaced fluid will be strictly proportional to rotational angle of the

shaft 20 (up to the accuracy of the 13 surface of the cavities and the other internal components). If this twin arrangement operates in hydraulic motor (turbine) mode then the rotational angle of the shaft 20 will be proportional to volume of the transmitted fluid. In other words, we obtained a pulsation -free rotary pump or hydraulic motor. Such pumps and hydrauhc motors are well

applicable in every case when well controlled volumetric flow or rotation with significant pressure drop or torque is required. From among the great variety of possible applications a few is described below.

hi Figs. 6 and 7 a hydrauhc circuit is presented which consists of two twin rotary

assemblies: a pump 71 and a motor 72. Excluding the high pressure line 76 and the low pressure line 77, die other auxiliaiy elements of the circuit are application dependent, thus optional. It

follows from the facts described above that the rotation of the .shaft of the motor 72 is proportional to the rotation of the shaft of the pump 71 and die transmission ratio is determined by die volume ratios (and secondarily the slip) of the two assembhes.

The buffer volume 73 may be connected to any point in the circuit and it is required only

if the circuit is closed and the heat expansion of the working fluid significantly differs from that of the solid components. If some extent of elasticity is beneficial fiom the point of view of the application then it should be connected to the high pressure line 76.

When the circuit is completed with the three-way two-positiou routing valve 74 and die shorting line 78, then in the state corresponding to Fig. 6 the torque transmission will take place, while in the state as shown in Fig. 7 the pump runs in idle mode. In the working state of the circuit the routing valve 74 leads the fluid fiom the outlet of the pump dirough the high pressure

hue 76 toward the inlet of the motor 72. while the shorting line 78 is closed. In idling mode the high pressure line 76 is closed and the fluid from the outlet of the pump is directly recycled dirough the shorting line 78 toward its inlet. If the routing valve is of overlapping type then in its middle state a fraction of the fluid flow will go toward the line 76 while the other part of the fluid goes dirough the hue 78, ensuring a smooth transition of the circuit from one state to the other.

By adding a further shorting line 79 to the circuit that contains die check valve 75, one

obtains a free wheel driving arrangement. Whenever due to either some outer force or its inertia the shaft of the motor 72 would rotate faster than it is determined by die transmission ratio of the circuit, the check valve 75 opens letting through the excess flow produced by the motor 72

in pump mode. If the flow through the check valve 75 can be controlled from outside dien the overrun of the shaft of the motor 72 can be controlled or braked. In the state of the circuit corresponding to Fig. 7, when die pump 71 is idling, the full range braking of the shaft of the motor 72 can be realised.

Fig. 8 presents a hydrauhc circuitry containing three twin chamber rotary assemblies;: one 71 working in pump mode and die odier two 72, 72a working in motor mode. The high pressure line 76 branches symmetrically into the lines 76a and 76b, which lead to the inlets of the

hydrauhc motors 72 and 72a. The outlets of die motors 72 and 72a merge into the low pressure line 77, connected to the inlet of the pump 71. The torque produced on die shafts of the two driven motors 72.72a is equal to each other and is proportional to the pressure difference between the high pressure 76 and die low pressure 77 lines. The sum of the rotations of the shafts of the two driven motors 72,72a is proportional to the rotations of the driving pump 71. In summaiy, the behaviour of this cucuit very well corresponds to die classical planetary gear differential driving mechanism.

When the circuit in Fig. 8 is completed with the routing valve 74a. the overrun

controlling check valves 75a and 75b, and the buffer volume 73, then the features as described above can be added to the circuit.

We obtain a rather specific kind of differential driving mechanism by adding the valve 81 to the circuit. The function of this valve is to balance the flow difference between the branches 76a and 76b through a negative feedback. (The details of such a valve do not belong to this invention.) The advantage of applying such a flow balancing valve 81 is that it solves die inherent shortcoming of the mechanical differential drives, the twirling that occurs when the

braking torque on one of die shafts of the motors 72,72a is much lower than on the other shaft. The flow balancing valve tends to decrease the flow rate in the branch passing a higher volumetric flow (and as a result decreasmg the torque on the shaft of that motor) while increases the flow rate in the other branch, causing a higher torque on the shaft of the motor on this side.

Such a feature can be created with the mechanical differential drives only in a very comphcated way though it is very beneficial for most vehicle drives.

A further feature of this kind of hydrauhc differential drive is that - in contrary to the traditional mechanical drives - it causes no trouble at all to drive more than two motors in differential mode by creating multiple branches. If a circuit with stepwise binary branching is apphed, the flow balancing valve can also be applied. Such a driving mechanism could especially be advantageous for vehicles designed for heavy terrain with four or more driven wheels.

If one modifies the circuit shown in Fig. 8 such a way diat it will contain on its driving side multiple pumps like 71. so that they are mounted on a single shaft, then a multiple stage torque converter is obtained which is well suitable for automatic control. Such a scheme is shown in Fig. 9. containmg three driving side pumps, 71, 71a and 71b. The common shaft 91 of the pumps can be driven e.g. by an internal combustion engine. The driven side as shown in Fig. 9 is a differential driving circuit - corresponding to Fig. 8 - diough it could be any .sub-circuitry containmg some hydraulic motors. The outlets of the pumps 71 , 71a. and 71b are connected to the volume 92 which leads die fluid further tluough the high pressure line 96. The role of the volume 92 is no more than ensuring a low resistance connection between its inlets and its outlet. The fluid returning fiom the driven side enters the volume 93 mat divides it toward the inlets of the driving pumps 71. 71a, and 71b. The transmission ratio between die shafts of the driving and the driven side can be changed in this hydraulic circuit by using the routing valves 74b, 74c, and 74d. When all the three routing valves are in idling state (as the state of the valve 74c in Fig. 9), then die whole transmission circuit is in idle (neutral) state. When the pump having the smallest

volume (e.g. the pump 71 b with the valve 74d) is switched on then the transmission provides the highest transmission ratio, analogue to the lowest gear with mechanical transmissions. When this pump switched off and the pump next in volume (e.g. pump 71a) is switched on simultaneously, men die second transmission ratio can be set. The next transmission ratio can be obtained for example keeping the pump 71a on and switching on the pump 71b, as well. The lowest

transmission ratio - corresponding to the highest gear - is set when all the pumps 71, 71a, and

71b are in on state. It is a notable feature of this circuit that it does not require any kind of clutch for switching fiom one state to the other, assuming that the routing valves have such intermediate position when both of the controlled branches are partially open.

The number of different transmission ratios of such a circuit depends on the number of pumps in the circuit and the relative volume ratios of the pumps. When the volume ratios are well chosen then with two pumps (71, 71a) three transmission ratios can be obtained, widi diree pumps (71. 71 a, and 71 b) seven and with four pumps 16 different ratios can be obtained.

If one out of the driving side pumps 71, 71 a, and 71b is connected into die circuit in opposite way compared to the others (i.e. its inlet is connected to volume 92 and its outlet to volume 93 ) then a reverse stage of the transmission is created. If the reversed pump has the

smallest volume (e.g. 71b) men it can be turned on also in the forward stages of die transmission, thus increasing the number of different forward stages. In tihis way the transmission can have one reverse and six forward stages.

In Figures 10 and 1 1 the principle and the operation of an internal combustion engine is presented. The construction shown here consists of two rotary assembhes; both are analogue to one shown in Fig. 1. and are situated in the housings 10 and 100, respectively. The assembly in the housing 100 with its shaft 201, vane 301. and its cavity 131a serves as the combu^ion

chamber, while the assembly in the housing 10 with its shaft 20, vane 30, and its cavity 13a serves as the compressor. The outlet 15 of the compressor cavity 13a and die inlet 141 of the combustion cavity 13 1a are connected to each odier through die passage channel 18 that can be

closed and opened by the valve body 40. which is movably mounted to the housing 10 and/or the housing 100. It seems advantageous if this valve body has a disc like shape.

One can also notice in Fig. 10 that there are the fuel injectiou nozzle 50 and the ignition

equipment (spark plug) 60 in the passage channel 1 . in diis case both are on me side of die cavity 131a. The synchronised rotation of the shafts 20 and 201, as well as die valve body 40 is ensured by appropriate gearing, which is not shown in the drawings. The detailes of this gearing, as well as of the necessaiy synchronising tools for the fuel injection and the ignition devices do not belong to the circle covered by the invention, since many traditional solutions are available for the task.

The shafts 20 and 201. as well as the shaft of the valve 40 should rotate exactly at the same speed, keeping their relative rotational angles fixed. These relative angles has to be determined such a way that right after the moment when the edge of the vane 301 of die combustion chamber 13 1 a has left the rim of the connecting passageway 18, die opening 41 of the valve body 40 opens to let dirough the compressed air fiom die cavity 13.a toward die expanding volume of the combustion cavity 13 1a. In this veiy moment die vane 30 in die housmg 10 is approaching the rim of the outlet opening 17, but it does uot reach it yet. Fig. 10 represents this position of the vanes 30. 301 and the valve 40.

As the shafts rotate further and a part of the compressed air has already flown into the

combustion chamber, the fuel injection nozzle injects the necessary amount of fuel into the combustion chamber 1 l a. Right before the edge of the vane 30 would pass the rim the outlet

opening 17, the valve body 40 closes the passageway 18, confining the compre^ed air-fuel rnixture in die cavity 131a and die ignition device 60 ignites the mixture upon this moment, starting the expansion, working phase. Aiound this time inside the other end of the vane 30 in die compression chamber 13a confines a new volume of ah' and starts compressing it; while simultaneously on the odier side of die vane toward the inlet opening 14 a new sucking phase is

started. This moment is presented in Fig. 1 1.

Following this moment the expansion phase lasts for about half a rotation of the shafts ( 180 degree or somewhat more) until the edge of the of die vane 301. that confines the

expanding volume reaches the rim of the exhaust opening 15 1. The exhaust phase goes in parallel with the next working phase on the odier side of the vane 301. Thus, during each full rotation of the main shaft 201 two working phases take place, just like in case of a traditional four cylinder reciprocating engine.

The necessaiy lubrication of the moving parts of the engine can be solved preferably by pressiu the lubricant through appropriate axial passageways within the shafts 20 and 201 toward the long edges of the vanes, which will distribute the lubricant with dieir movement within the

cavities 13a and 13 1a. respectively.

As an alternative solution for this internal combustion engine the shafts 20 and 201 can be created as a single piece. This form is in fact a more preferred embodiment, though it is more difficult to present in a drawing. In this variant the passage channel 18 can be manufactured into the planar separating walls between the two chambers, and the disc-like valve body 40 could be mounted on the common shaft, as well. This construction offers several advantages over the one shown in Figures 10 and 1 1 : no synchronisation equipment is required between the .shafts 20 and 201. the valve body 40 can either be mounted on the common shaft or its driving gearing is

more simple due to the parallel shafts; thus the construction is more compact and efficient. Either the arrangement shown in Figs. 10 and 1 1 or its alternative single shaft form can be multiplied, e.g. if two such assembhes are momited on a single main shaft such a way that the vanes 301 of the two combustion chambers are perpendicular to each otlier then an engine analogue to an eight cylinder reciprocating combustion engine is obtained. It is also important to emphasise that the restrictions on the shape of the cavity of the compression and the combu.stion

chambers allow a great degree of freedom to optimise the expansion characteristics of the engine corresponding to virtually any kind of fuel.

The rotary assembly according to this invention can be well applied whenever high performance positive displacement pumps or hydraulic motors are required or pulsation free

fluid flow or constant torque and rotational speed hydraulic motor is required. When several of such assemblies are applied in a hydraulic circuit, different torque transmission devices can be created diat show several beneficial features above the traditional mechanical solutions. By combining two assemblies a well tuneable, high performance rotary internal combustion engines

can be created.

Claims

THE CLAIMS:

1. A rotary assembly consisting of a housmg wi a cavity, that is bounded by the first and the second pianai walls, as well as by a curved, closed surface in-between, with inlet and

outlet openings connecting to the cavity, the rotatably mounted shaft with an axis perpendicular to the planes of planar walls, furnished by a slot, parallel and symmetrical to the axis of die shaft and limited wimin die section of the shaft inside the parallel walls of the cavity; with one or more

vanes fitted into the slot which divide the cavity into two or more sub-sections; which is ch a r a c t e r i s e d by that the end surfaces of the vane (vanes) (30) toward the curved surface ( 13) of the cavity follow rounded curves (3 1, 32) in cross section parallel to die planar walls ( 1 1, 12) of the cavity, while in any such cross section of the curved surface ( 13) of the cavity follows a non-circular curve ( 13b), having a primary internal fitting point (O) which hes on the rotational axis (21 ) of the shaft (20) and this non-circular curve ( 13b) is determined such a way diat the rounded end surfaces (3 1. 32) of the vane (30) are in fluid-tight contact along two opposite generatrices ( 13c, 13d) with die curved surface ( 13) of the cavity ( 13a) regardless the

angular position of the shaft (20); the shaft (20); the shaft and the internal curved surface ( 13) of the cavity are also in a permanent fluid-tight contact at least along a single fixed generatrix ( 13e) or a range of generatrices of the curved surface ( 13); while the inlet ( 14) and die outlet ( 15) openings are on the two sides of this contact range ( 13e).

2. A rotary assembly according to Claim I which is ch a ra ct erise d by identical circularly rounded end surfaces (31a. 32a) of the vane (30) and die cross section of the curved surface ( 13b) of the cavity follows a geometrical curve which is an outer parallel of an equicord

curve - i.e. satisfying the equation r(φ)=2c-r(φ-π) in polar co-ordinate system centred at (Q), equivalent to the primary fitting point of the curve (O) - at the distance of the rounding radius

(R) of die vane (30).

3. A rotary assembly according to Claims 1 or 2 which is characterised by that the vane (30) is a sohd, single piece component.

4. A rotary assembly according to Claims 1, 2, or 3 which is characterised by a housing (10) that contains at least two separate cavities (13a, 131a) near to each other with separate vanes (30, 301 ) within them.

5. A rotary assembly according to Claim 4 which is cha acterised by mat die vanes (30,301) in the cavities (13a, 13 la) are fitted into the slots of die same shaft (20) that traverses bodi cavities ( 13a.131 a ).

6. A rotary assembly according to Claim 4 or 5 which is characterised by identical cavities ( 13a.131a). with vanes (30,301) in them perpendicular to each odier in projection to a plane perpendicular to the shaft (20) axis (21) and the inlets (14,141) of die cavities (13a, 131a) divide from a common iidet (16). as well as the outlets (15,151) of die cavities merge into a

common outlet (17).

7. A rotary assembly according to Claim 4 or 5, which is characterised by diat the outlet (15) of the first cavity (13a) in its housing (10) is connected to the inlet (141) of the second cavity (131a) and there is a movable valve body (40) in die connecting channel (18) that operates in a synchronised way with the single shaft (20) or the shafts (20,201) that encompass die sliding vanes (30.301); and there exists - preferably at one side of die valve (40) - a fuel injection nozzle (50) and an igiiiting equipment (60).