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Title:
APPARATUS FOR TRANSFORMING PRESSURE AND/OR FLOW MOTION OF A FLUID TO ROTATIONAL MOTION OF A BODY,OR VICE VERSA
Document Type and Number:
WIPO Patent Application WO/1980/000601
Kind Code:
A1
Abstract:
An apparatus for transforming pressure and/or flow motion of a fluid into rotational movement of a body, or vice versa, which apparatus includes a house (1), a central screw (3) and at least one additional screw (5a, 5b) cooperating therewith, said screws being positioned in channels (2, 4a, 4b) in said house. Pipe members (6a, 6b) are provided for the supply of a fluid to the channels of the house, said central screw being fixed to one of said pipe members. An energy transfer means (1, 30, 35) is provided integral with said house for transferring, in respect of a unit exterior to the house, a rotational movement from or to said house. For permitting supply and discharge of fluid at the same end of said house, said pipe members are disposed in each other, the inner pipe member (6b) communicating with a channel through said central screw for conveying said fluid to the other end of said house where the fluid is diverted by an end wall to be conveyed back through the channels in the house.

Inventors:
Cederquist W.
Application Number:
PCT/SE1978/000038
Publication Date:
April 03, 1980
Filing Date:
September 07, 1978
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
Cederquist W.
International Classes:
F01C1/16; (IPC1-7): F04C1/10; F01C1/16
Foreign References:
SE7702501A
US1780338A
US3263619A
US3264944A
US3479960A
GB2308194A
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Claims:
CLAIMS
1. Apparatus for transforming pressure and/or flow motion of a fluid into rotational movement of a body, or vice versa, which apparatus includes a first screw member (3) positioned in a central, first through channel (2) in a house (1), and provided with at least one thread around its periphery, said screw member (3) being arranged to cooperate with at least a second screw member (5a, 5b) which is positioned in a second channel (4a, 4b) in the house parallel to said first channel, said second channel along at least a portion of its extension communicating with said first channel, the thread of the second screw member being complementary with and engaging the thread of said first screw member, characterized in that a first pipe member (6a) which is fixedly connected to said first screw member (3) is in fluid tight rotational relation to the channels (2, 4a, 4b) of said house at one end thereof, while the other end of the house (1) is closed, that said first screw member (3) has a.longitu dinal through channel, that at one end connects to a second pipe member (6b) within said first'pipe member (6a) defining an annular channel between said pipe members (6a, 6b), and at its other end communicates with said channels (2, 4a, 4b) in the house for defining a flow path for the fluid from said second pipe member (6b) via said channel through said first screw member (3), and said channels (2, 4a, 4b) in the house to the annular channel, or vice versa.
2. Apparatus as claimed in claim 1, characterized in that said house (1) is embodied as an energy transfer means for transferring energy between said house and a unit disposed exterior to the house.
3. Apparatus as claimed in claim 2, characterized in that said energy transfer means comprises a rotor in an electrical machine, which rotor is integral with said house (l),an electrical machine stator, which is adapted to the rotor, being provided around the house (1).
4. Apparatus as claimed in claim 1, characterized in that said house (1) is provided as a hub for a rotational member.
5. Apparatus as claimed in claim 4, characterized in that said rota¬ tional member is a wheel.
6. Apparatus as claimed in claim 4, characterized in that said rota¬ tional member is a wheel (30) provided with teeth. OMPI ,_ . iro .
7. Apparatus as claimed in claim 4, characterized in that said rotational member is a drive pulley (35).
8. Apparatus as claimed in any one of claims 4 to 7, characterized in that said first pipe member (6a) is rotationally supported on a 5 frame.
9. Apparatus for transforming pressure and/or flow motion of a fluid into rotational movement of a body, or vice versa, said apparatus includ÷ ing a first screw member (3) positioned in a central first through channel (2) in a house (1) and provided with at least one thread around.
10. its periphery, said screw member (3) being disposed for cooperation with at least one second screw member (5a, 5b) which is positioned in a second channel (4a, 4b) in the house parallel to said first channel, which second channel (4a, 4b) at least along a portion of its extension communicates with said first channel, the thread of the second screw 15 member being complementary with and engaging the thread of said first screw member, said first screw member (3) being stationary and said house (1) being rotatable, and said house (1) being provided with an energy transfer means (11, 30, 35) for transferring rotational movement to or from said house in respect of a unit disposed exterior to said 20 house characterized in that said house (1) is integral with said ener¬ gy transfer means (11, 30, 35) and that said screw member (3), at least at one end (3a) thereof, projects from the house and at this end is fixed to a pipe member (6a) connecting to said first channel (2) of the house. 25 10. Apparatus as claimed in claim 9, characterized in that said energy transfer means is comprised of the rotor (11) of an electrical machine, and that said rotor (11) defines said house (1), said channels (2, 4a, 4b) extending axially through said rotor.
11. Apparatus as claimed in claim 9, characterized in that said 30 energy transfer means is comprised of a transmission member (30, 35), , . and that said transmission member (30, 35) is fixedly connected to said house.
12. Apparatus as claimed in claim 11, characterized in that said transmission member is an annularly shaped member (30, 35) extending around 35 said house and being provided with means for engaging a belt, or provided with teeth.
13. Apparatus as claimed in any one of claims 9 to 12, characteriz ed in that only one end of said first screw member (3) projects from sa house (1), the other end of said house (1) being closed, that said first screw member (3) has a longitudinal through channel, that at one end connects to a second pipe member (6b) within pipe member (6a) thereby defining an annular channel between said pipe members (6a, 6b) and at its other end communicating with said channels (2, 4a, 4b) in said house for defining a flow path for the fluid from said second pipe mem¬ ber (6b), via said channel through said first screw member (3) and said channels (2, 4a, 4b) in said house to the annular channel, or vice ver.
14. Apparatus as claimed in claim 1 or 9, characterized in that at least one screw member (3, 5a, 5b) has a structure incorporating a cylindrical core around the periphery of whichat least one strip or wire member is wound for defining threads, and that said strip or wire member at its ends is fixed to said core, while being movably arranged intermediate its ends.
Description:
APPARATUS FOR TRANSFORMING PRESSURE AND/OR FLOW MOTION OF A FLUID TO ROTA_ TIONA MOTION OF A BODY . OR VICE VERSA

The present invention relates to an apparatus for transforming pressure and/or flow motion of a fluid, to rotational motion of a body, or vice vers .

TECHNICAL FIELD Such apparatus include pumps in which the rotational movement of a ' rotatable body is imparted on a fluid, and motors in which the flow motion of a fluid is imparted on a rotational body. As disclosed in the following description the apparatus according to the invention has yet wider appliancies and advantageously may be incorporated as a rotor means in an electrical motor or an electrical generator.

PRIOR ART The apparatus according to the invention is based on the technique of screw pumps.

Screw pumps include at least two screws which operate in engagement and are provided rotatably in channels of a pump house against which they make contact, such that the fluid surrounding the screws is displaced in the longitudinal direction of the screws under influence of movement of the threads of the screws.

A prior art screw pump operates with three screws, a central screw and two peripheral screws, of which screws only the central one is driven. The peripheral screws are provided diametral y opposed in engagement with the central screw. These outer screws run freely and serve as sealing slides.

In this prior art screw pump the house is stationary and the central screw is connected to a motor for rotation in the house.

U.S. patent specification No. 3,263,619 discloses a screw pump having a central screw and several peripheral screws engaged therewith.

The central screw is stationary while the pump house is rotational. On the casing portion of the house a rotor means of that kind which is part o an electrical machine is attached, while a suitable electrical stator surrounds -the rotor and is supported in a case, in relation to which the central screw is stationarily fixed.

In operating this latter apparatus as a screw pump the house is cause to rotate in that the rotor of the electrical machine is rotated. In thi way a fluid can be conveyed between the stationary central screw and the peripheral screws which latter in view of engagement with the stationary screw are brought to rotation when the house is rotated.

The screw pump described in said U.S. patent specification No. 3,263, in several cases operates well. However, the structure of this screw pump is both compl cated and bulky. Moreover, the medium to be conveyed is fed to one side of the screw pump and taken out on the other side which is an obstacle to many appliancies of the screw pump.

PURPOSE OF THE INVENTION The purpose of the invention is to achieve a new apparatus for trans¬ forming pressure and/or flow motion of a fluid to rotational movement of a body, or vice versa, which apparatus has an essentially simpler and less bulky structure than prior art screw pumps of this kind.

This purpose is achieved by means of an apparatus for transforming pressure and/or flow motion of a fluid to rotational movement of a body, or vice versa, which apparatus comprises a first screw member provided in a central, first through channel in the house and provided with at least one thread around its periphery, which screw member is adapted for cooperation with at least one second screw member disposed in a second channel in the house in parallel with the first channel. The second channe communicates with said first channel along at least a portion of its exten sion, the thread of the second screw member being complementary with and engages the thread of the first screw member.

According to the invention this apparatus is distinguished in that a first pipe member fixedly connected to said first screw member is in fluid tight rotational relation to the channels of the house at one end of the house, while the other end of the house is closed, that the first screw me ber has a longitudinal through channel which at one end connects to a se-

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cond pipe member within the first pipe member establishing an annular channel between said pipe members, and at its other end communicating with said channels in the house for establishing a fluid flow path from the second pipe member through the channel of the first screw member and the channels of the house to the annular channel, or vice versa. The threads of the screw members may be conventionally embodied. However, according to a preferred embodiment the threads are embodied as a cylindrical core around the periphery of which at least one strip or wire member is wound for forming threads, said strip or wire member at the ends thereof being attached to the core while between said ends being provided for movement.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is described more in detail in the following and with reference to the enclosed drawing including Figs. 1 to 4.

Fig. 1 is a partly broken and partly longitudinally sectioned view of a first embodiment of the apparatus according to the invention employed as an electrically driven pump, or a generator driven by means of a fluid for producing an electrical current. Fig. 2 is a cross-section of a second embodiment of the apparatus according to the invention, a toothed transmission member being provided on the house of the apparatus around its casing portion; the apparatus according to this embodiment may be employed as a pump driven by means of the transmission member, or as a fluid motor where the power is taken out over the transmission member.

Fig. 3 depicts the apparatus according to the invention employed as a pump driven by means of a drive belt, or as a fluid motor transferring kinetic energy to a drive belt.

Fig. 4 illustrates a view similar to Fig. 1 of another embodiment of the invention which is suitable to operate as a hub in a wheel.

PREFERRED EMBODIMENTS OF THE INVENTION AND INDUSTRIAL APPLICABILITY

In Fig. 1 one embodiment of the apparatus according to the invention is disclosed, which embodiment primarily is intended for use as an electric- ally driven pump for conveying a fluid. However, as is evident from the following description below this embodiment may also be utilized as an electrical generator for generating electrical current.

In Fig. 1 the unit which is essential for the invention is referenced

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10 and is surrounded- by a unit 20 which, as mentioned below, is comprised of a stator in an electrical machine. In the following the unit 10 is first described. This unit is also shown in cross-section in Fig. 2, where, however, the unit is provided with a gear 30. The unit 10 comprises a house 1 as a cylindrical body having a longitudinal, central cylindrical through channel 2 and two diametrically opposed cylindrical, likewise through channels 4a and 4b. The diametrically opposed or peripheral channels 4a, 4b are parallel with the central channel 2 and their central axes are dis¬ posed in the same plane as the central axis of the central channel, each at a distance therefrom which is less than the sum of the radius of the cen¬ tral channel and the radius of the peripheral channel in question. Thus, the peripheral channels intersect the central channel and there is communi¬ cation between the central channel 2 and the peripheral channels 4a, 4b along their entire extensions. - A central screw member 3 is provided in the central channel 2 in rota¬ tional relation to the house, the threads of the screw member sealing against the walls of the channel 2. In the same manner rotational screw members 5a and 5b with the threads are provided in each of the peripheral channels 4a and 4b, respectively, outer surfaces of the threads of said screw members sealingly engaging the boundary surface of the respective channel .

The threads of the peripheral screw members 5a, 5b are complementary with the threads of the central screw member 3 and are in sealingly engage¬ ment therewith. The central screw member 3 is provided stationary while the house 1 is rotatable.

The apparatus described above essentially corresponds to the embodi¬ ment of the previously known screw pump according to said U.S. patent spe- c.ification. In the embodiment illustrated in Fig. 1 the unit 10 is thus structured t the central screw member 3 with both its end portions extends from the house 1 and is inserted into cylindrical pipe members 6a and 6b, respec¬ tively. The central screw member at one end portion 3a at least thereof is rigidly fixed to the associated pipe member 6a, e.g. by press fitting. Between the pipe members and the house 1 a sealing means 8 of suitable kind is provided for preventing fluid leakage. This sealing means 8 can be embodied in numerous different ways, all as to wish. However, in the embodi¬ ment illustrated in Fig. 1 said sealing means is comprised of a circular end plate which by press fit is fixed in a recess in the house at the end

portion thereof, said recess being coaxial with said first channel. A sealing ring 12 is positioned between the bottom of said recess .and the end plate.

The peripheral screw members 5a, 5b at their ends are embodied cone- -shaped tapering into a cylindrical pin part having reduced cross-section for reduction of friction, if any, between the peripheral screw members and said sealing means 8.

The embodiment of Fig. T is adapted for electrical drive. To this end the house 1 is embodied as a rotor of an electrical machine with a stator 20, which is schematically disclosed in phantom. The electrical machine formed by house 1 and stator 20 can be of any suitable kind, appropriate electrical adaptation being provided between house 1 and stator 20.

Thus, in the embodiment according to Fig. 1 house 1 is provided with energy transferring or transforming means (the rotor) adapted to im¬ part rotational movement to the house from a unit (the stator) positioned exterior to the house, or to receive rotational movement from the house for transferring this energy to a unit (the stator) positioned exterior to the house. In that case the embodiment according to Fig. 1 is intended to be used as a pump, house 1 may be structured as a rotor of any kind of electrical motor, both DC- or AC-type, stator 20 of course being adapted to the struc¬ ture of the rotor. In AC-appliancies the motor may be of one phase of multiple phase type. In that case a reversible operation of the pump is required, such a motor is of course used that permits simple reversion of the direc¬ tion of rotation on the control panel of the motor.

In that case the embodiment of Fig. 1 is intended to be used as a fluid generator for producing current, the house or the rotor, similarly to the above, may be of either DC- or AC-type, dependent on the wish for producing DC or AC-current. In this case house 1 can be embodied as a rotor of any suitable electrical generator, the stator of course being adapted to the structure of the rotor.

Supposing the embodiment of Fig. 1 relates to an application of the apparatus according to the invention as a pump for conveying a fluid through pipe members 6a, 6b, then the rotor, i.e. house 1, preferably is structured as the rotor of an asynchronous motor. Thus, the house is provided with a sheet package having electrical conductors 11 countersunk in its casing portion. Stator 20 is provided with corresponding windings (not shown),

for the driving of rotor 1. Electrical power is fed to stator 20 over leads 22, It is evident that the channels 2, 4a, 4b are made through the sheet package of house 1 and so a simple method of manufacturing is achieved. In case the fluid conveyed through house 1 tends to create corrosion or in any other way interfere with the boundary walls of the channels 2, 4a, 4b, these walls are preferably covered by means of a protective coating, or the channels are made in a bushing which is fastened within house 1.

In the embodiment according to Fig. 1, where the central screw member is rigidly attached to the pipe member 6a, a bracket 9 is provided between stator 20 and pipe member 6a fer the fixing of this latter. Stator 20 is fixed in space by means of its base plate (not shown).

Contrary to the " apparatus according to said U.S. patent specification No. 3,263,619, in the apparatus according to the invention the energy trans¬ ferring means is integrated with the house. ' In this way a.compact and simp- le apparatus is achieved.

It is appreciated that unit 10 within the scope of the invention can take great variety of embodiments, all of which disclose the characterizing features of the invention, viz.

1) that the central screw member is stationary attached to at least one of the pipe members for the feed and the discharge of a fluid, and

2) that the house is rotational and is provided with an energy trans¬ fer means for transferring rotational movements onto or from the house.

Thus in unit 10 both the pipe members or only one thereof may extend into house 1, the sealing means 8 being modified for suitable adaptation thereto.

House 1 does not either need to have cylindrical shape. However, for achieving balance in rotating the house it is preferred that the house has a symmetrical cross section in view of at least one lateral axis.

Moreover, the peripheral screw members 5a, 5b can be provided with threads along a limited portion of their extensions, in which case communi¬ cation between the central channel 2 and the peripheral channels 4a, 4b can be limited to said portion. Moreover, the peripheral channels 4a, 4b in house 1 need not be through channels but can be closed at one end thereof by means of a wall fixedly connected to the house 1. The end portions of the peripheral screw members 5a, 5b may also be arbitrarily shaped; the shape of the end portions of the peripheral screw members disclosed in Ftg. 1 is preferred since this shape provides a reduced contact surface against said sealing means 8, the friction action thereby

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becoming small .

The central screw member 3 can also be fixed at both its ends to the associated pipe members 6a, 6b.

Moreover one of the pipe members can be attached to the house. This is particularly advantageous when unit 10 is employed as an oil pump for feeding oil to a combustion chamber, in which case the end of the pipe member facing away from house .1 can be bent and provided with means for discharging the oil into the combustion chamber at an angle to the pipe axis. When operating the pump the discharge end will rotate and the oil is spread over large area in the combustion chamber.

In electrical appliancies house 1 preferably has its ends or end por¬ tions prolonged from the associated stator unit, the sealing against the pipe member 6a, 6b. being made outside the electrical machine. In this way greater safety is achieved in operation, since a failure in said seal- ing means will not permit leaking fluid to damage the electrical machine. Moreover, it is appreciated that if house 1 of the apparatus is a rotor of an electrical machine, this machine either being a motor or a generator, conventional commutators, slip rings and brushes can be pro¬ vided if required for the particular appliance. Said sealing means 8 can also be completed by bearing means of any kind, if considered advantageous in any specific embodiment of the appa¬ ratus according to the invention.

Moreover, said screw members can have an arbitrary number of threads. It is realized that a greater number of threads result in a better sealing between the screw members and permits a higher pressure at the discharge end, when unit 10 is utilized as a pump.

The pitch of the threads of the screw members is not critical but can be adapted to a value suitable for each application. A lower pitch will result in a better sealing between the screw members. Moreover, an increase of the distance along which the threads of the screw members engage each other also result in an ability of unit 10 for providing high pressure at its discharge end, when said unit is utilized as a pump.

In the above description and according to the embodiment of Fig. 1 all screw members are cylindrical. However, in the apparatus the screw members may be embodied as other bodies of rotation and in that connection also the associated channels, such as cones or truncated cones. In this latter case,

which due to more difficult conditions of manufacturing is less appropriate, the top of the central conical screw member is positioned adjacent the base surface of the peripheral conical screw members.

The shape or cross-section of the threads is substantially trapezoi- dal. However, said threads can have any suitable cross-section, which for the application in question permits an appropriate or required sealing between the screw members and the house on one hand, and between the central screw member and the periphera-1 screw members on the other hand.

Above and in the following description of the invention as well as in the claims the expression "screw member" includes any type of rotational body, the periphery of which is provided with one or several ridges or threadsspirally wound around said member, grooves being defined between adjacent ridges or threads. Conventionally the threads are made integral with the rotational body as a " screw member. However, in accordance with the invention one or several of the screw members can ibe comprised of a core having one or several strips or wire members spirally wound around the core, and having desired cross-section. In this case a cylindrical core is pre¬ ferred. Preferably said wire member is comprised of spring wire material, the ends thereof -being fixed to the core, e.g. by welding, while said wire member intermediate its fixed points is displaceable in the longitudi¬ nal direction of the core. It is realized that also for this embodiment of the screw members, the threads of the central screw member formed by the wire member is to be complementary with the threads of said one or several peripheral screw members. Of course all screw members need not be structur- ed in one or the other way, but it is only required that the threads are complementary structured for giving the required sealing against the boundary walls of channels 2, 4a, 4b in the house 1 on one hand, and between the central screw member and the peripheral screw members on the other hand. It is realized that the capacity of the apparatus of the invention entirely is a matter of dimension which is substantially dependent on the diameter of the screw member and the number of peripheral screw members, which cooperate with the central screw member.

Although the embodiment of the apparatus of the invention which has been described with reference to Fig. 1, includes two peripheral screw members 5a, 5b which cooperate with the central screw member 3, any number of the peripheral screw members can be arranged in the house in associated peri¬ pheral channels. For securing balance of the house and uniform operation in the apparatus it is required that the peripheral screw members are

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uniformly distributed around the central screw member. A greater number of the peripheral screw members results in an increased capacity of the apparatus although the pressure, which can be attained with the apparatus when utilized as a pump, on the output side of the apparatus will be less. In the embodiment according to Fig. 1 of the apparatus of the inven¬ tion the peripheral screw members are shown with a smaller dimension than the central screw member. This relation depends on the fact that in view hereof the radial dimension of house 1 can be maintained reasonable. However, it is appreciated that the diameter of the peripheral screw mem- bers can have any suitable dimension, if considered advantageous, indepen¬ dent of the diameter of house 1, as long as the rigidity of the house is maintained.

The embodiment of Fig. 2 discloses unit 10, house 1 around its casing portion being provided with an energy transforming or transferring means embodied as a transmission member 30 provided with teeth, which member is meant tb engage a corresponding member for transferring or transforming rotational movement to or from house 1.

The embodiment of Fig. 3 discloses unit 10 utilized in connection with a belt 40, which is provided for transferring rotational movement to or from house 1. In this connection the casing portion of house 1 is provided with an energy transferring means inplemented as a transmission member 35 in the shape of a drive pulley belt 40. If desired, recesses adapted to the cogs or teeth of a driving belt can be formed in the surface of the drive pulley or the casing portion of the house. In this embodiment the two pipe members 6a and 6b are shown ' fixedly mounted on a frame by means of a respective bracket 19.

It is realized that any kind of transmission member can be arranged on the casing portion of house 1, which transmission member permits the transfer of rotational motion between the transmission member of the house and a transmission member cooperating therewith. Of course, the type of transmission member is dependent on which type of transmission that is required.

The embodiment of Fig. 4 is particularly advantageous for utilization as a hub in a wheel or similar, where only one side of the apparatus is a ailable for the feed and discharge of fluid.

Similar to the embodiment according to Fig. 1 the apparatus according to the embodiment of Fig. 4 includes a house 1 shaped as an essentially cy¬ lindrical body having a central through channel 2 and two opposite parallel

channels 4a, 4b closer to the periphery of the body. The latter channels along their extensions communicate with the central channel along at least one part of communication. Likewise a central screw member 3 is positioned in the central channel 2, which screw member over said communication parts engage a peripheral screw member 5a, 5b in each of the peripheral channels.

The apparatus according to Fig. 4 differs from the embodiment accord¬ ing to Fig. 1 in that the feed and discharge of fluid take place at the same side of house 1. Thus, a pipe member 6a is provided rigidly fixed to the central screw 3 which protrudes from house 1. The central screw 3 have a longitudinal through channel (not shown) which communicates with an interior pipe member 6b coaxially positioned within pipe member 6a. Preferably, the connection between interior pipe member 6b and central screw 3 is rigid but could also be made for permitting mutual rotation, if desired.

As shown in Fig. 4 central screw 3 protrudes out from house 1 only at one end thereof. At the other end of house 1 screw 3 terminates at the level of the peripheral screws and at this end the house is closed by means of an end wall . House 1 is provided with members of attachment or mounting for the fixing of an energy transfer means such as a transmission member in the form of a gear or a drive pulley. Thus, in Fig. 4 members of attach¬ ment shaped as longitudinal key grooves 12 are shown on the casing por¬ tion of the house. Instead of having members of attachment for the fixing of a transmission member house 1 can be embodied as the rotor of an electrical machine, in which- case, like the embodiment of Fig. 1, a stator is provided around the rotor and is fixed to the pipe member 6a. In this case the rotor is the energy transfer or transforming means. Having the above described structure the embodiment according to Fig. 4 is provided to operate in the same manner as the embodiments of Figs. 1-3, the pipe member 6a being fixedly mounted to a base plate (not shown). Fluid is fed to one end of house 1, e.g. through the interior pipe member 6b in the direction of the arrow, and flows through the channel in the central screw to the other end of the house where the fluid impinges the end wall and diverts to flow back through the channels 2, 4a, 4b to operate on the peripheral screw members 5a, 5b which thereby cause house 1 to rotate.

The fluid flows out from house 1 through the space between central screw 3 andpipe member 6a to an annular channel formed between the pipe members 6a

and 6b ancfin the direction of'the arrows depicted therein.

It is realized that if the travel direction of the fluid is opposite to the direction of the arrows in Fig. 4 house 1 will rotate in the opposite direction. Instead of being discharged or fed in the axial direction the fluid in the annular channel between the pipe members 6a and 6b can be discharged or fed in a radial direction over a terminal means (not shown) on pipe mem¬ ber 6a. In this case the annular channel is closed at its end facing away from central screw member 3. In the embodiment according to Fig. 4 a sealing means 8 differently shaped from the sealing means in the embodiment of Fig. 1 is disclosed. Thus, pipe member 6a has a radial flange which faces the peripheral wall of the house. House 1 has at its end. facing pipe member 6a a portion protrud¬ ing inwards from" its casing portion. Between said pipe flange and said pro- truding portion the sealing means is positioned in form of a sealing thrust bearing. For the assembly of the entire apparatus the house is structured for being opened at either end (not shown).

It is realized that the peripheral screw members at their ends require bearingsand so does the central screw member 3 at its end facing away from pipe member 6a. Such bearingscan be implemented in a large number of ways by utilization of conventional technique and are not further discussed here.

In the embodiment according to Fig. 4 the same conditions as to the structure and the number of screw members are applicable as for the embodi¬ ment according to Fig. 1. However, as previously mentioned, in the embodiment according to Fig. 4 the house is preferably intended to serve as a hub of a wheel.For this case pipe member 6a as distinguished from the previously described embodiments is rotatably mounted on a frame (not shown) by means of a suitable bearing. On the house a wheel (not shown) is fixedly mounted by means of suitable members of attachment, e.g. the key grooves 12 which are shown.

Thus, the apparatus according to the invention can be utilized as a driving wheel assembly for vehicles, control of the fluid flow permitting rotation of the house and so the wheel fixed to the house, at a desired speed. The apparatus according to the invention permits a simple and effective assembly with.small exterior dimensions, which assembly can be utilized in connection with pumps, compressors, fluid motors and electrical generators.

The apparatus according to the invention is completely symmetrical, and in operation it can simply be reversed, if desired.