EP1088153B1 - Displacement machine based on the spiral principle - Google Patents

Description

Field of the Invention

The invention relates to a positive displacement machine for compressible media with two spiral conveying spaces arranged opposite one another in a fixed housing and with spiral displacement bodies engaging in these conveying spaces, consisting essentially of a central disc and spiral strips attached to each side of the disc, which are held eccentrically in relation to the housing are that during operation each point of the displacer executes a movement which is limited by the cylinder walls of the delivery chamber and is circular or elliptical-like, depending on the design of the guide device, and that the curvature of the strips is dimensioned such that they align the inner cylinder walls and the outer cylinder walls of the delivery chamber almost touches on at least one ledge of a sealing line that progresses continuously during operation, with an eccentric to guide the displacer relative to the housing arrangement, essentially consisting of a drive shaft and an eccentric disk arranged thereon, is provided.

State of the art

Displacement machines of the spiral type are known for example from DE-C-26 03 462. Machines of this type are mainly used as compressors for gaseous media. During operation of the machine, a number of roughly crescent-shaped work spaces are enclosed along a displacement chamber between the spiral-shaped displacement body and the two cylinder walls, which work spaces move from an inlet through the displacement chamber to an outlet, their volume constantly decreasing and the pressure of the working medium is increased accordingly.

A machine of the type mentioned at the outset, in which the spirals span an entire wrap angle of 360 ° or more, is known from DE 35 14230 A1. In such a machine, the spiral strips, axially protruding, are arranged on both sides on a disk having a hub for mounting the eccentric crank mechanism. Furthermore, the arrangement of the spiral strips is such that when the disk rotates in a circular manner, the resulting working chambers on both sides of the disk reduce their volume and the working medium is compressed. As a rule, the strips are arranged symmetrically with respect to the pane.

US-A-4677949 discloses a displacer for compressible media with two spiral conveying spaces arranged in a housing opposite one another and a displacer body engaging in these conveying spaces with a central disk and spirally attached strips which are composed of successive circular arc segments. The spiral strips converge radially inwards and, with the central disc, form radially inner high-pressure spaces in the conveying spaces. A conveying chamber is designed for the compression of a working medium and the opposite conveying chamber for expanding the working medium. The working fluid first arrives from an inlet in a delivery chamber, is compressed there radially inwards by displacement, then pressed into the second delivery chamber by a valve, relaxes radially outwards there on the way through the delivery chamber and is discharged from the second through an outlet Discharge chamber.

A displacement machine described in US-A-5094205 has a circumferential center disk with strips, which is arranged in the interior of an engine and form a compression delivery chamber and an expansion delivery room. The strips form high and low pressure spaces in the conveying spaces filled with a working medium, which have a larger volume radially on the outside than radially on the inside. The center disk has an opening radially on the inside in order to transfer the working fluid, an air / fuel mixture, introduced through an inlet from the compression delivery chamber into the expansion delivery chamber. There, the air-fuel mixture is ignited, expanded and the exhaust gases are discharged from the expansion delivery chamber through an outlet.

For work processes that are to be carried out at a pressure higher than the ambient pressure and in which there is only a slight pressure loss in the process, expansion machines are used in addition to the compression machines to exploit the residual pressure drop, which results in an improvement in the overall machine efficiency. Work processes that preferably work at higher pressure than the atmospheric pressure and in which a rel. Low pressure drop in the process arises, for example, fuel cell processes. Such processes are operated with commercially available compression and expansion machines in order to maintain the good efficiency of the oxidation of hydrogen in the fuel cell.

Presentation of the invention

The invention has for its object to configure a machine of the type mentioned in such a way that the working medium can be both compressed and expanded with only one displacement body circling in a housing, and with high compression pressure ratio heat transport from the inner hot end of the compressor-side strip through the center disc to the cold inner end of the expander-side bar.

According to the invention, this object is achieved by the features of claim 1.

The spiral strips attached to the center disk of the displacer on both sides are accordingly designed in such a way that on one side of the disk the volume of the work space enclosed by these strips and the associated conveying space is reduced as the displacement of the displacer progresses during machine operation. On the other side of the disc, the volume of the working space enclosed by this strip and the associated conveying space increases. The spiral strips, which are attached on both sides to the central disc of the displacer body, are asymmetrically attached to one another in comparison to the solutions known from the prior art.

The advantage of the invention can be seen, inter alia, in the fact that a very simple and consequently inexpensive construction of the machine can be realized, since both the compression and the expansion take place with only one movable displacement element.

The compressor-side delivery chamber generally extends from a low-pressure inlet arranged radially on the outside to a high-pressure outlet located radially on the inside. If, according to the prior art, the expansion-side delivery space now extends from a radially inner high-pressure space to a radially outside low-pressure outlet, the working medium on the compressor-side is - in the radial direction - conveyed against the direction of the working medium on the expanding side. This has the advantage that the loads on the center disk caused by the gas pressures and the spiral strips on the compressor and expander sides are approximately symmetrical.

If, on the other hand, according to the invention, the expansion-side delivery space also extends from a radially outer inlet to a radially inner low-pressure space, then the working medium on the compressor side - viewed in the radial direction - is conveyed in the same direction as the working medium on the expanding side. As a result, the inner ends of the spiral strips, viewed in the radial direction, come to lie on the expander side with respect to the center disk approximately opposite the inner ends of the spiral strips, also viewed in the radial direction. The connection of the inner ends of the spiral strips to the center disk is highly stressed during machine operation and is more or less hot depending on the pressure ratio on the compressor side. This arrangement has the advantage that when such a machine is used with a high compression pressure ratio, heat can be transported from the inner hot end of the compressor-side bar through the center disk to the cold inner end of the expander-side bar. This arrangement becomes important if a light metal with good heat conductivity is used for the production of the displacer. By Such light materials result in a relatively low centrifugal force of the displacer component in machine operation.

If the hub of the disk is surrounded on the compressor side by a high-pressure space, it is expedient for the interior of the hub to be sealed airtight with respect to this high-pressure space. As a result, a counterweight - provided for compensating the eccentric movement of the eccentric disc and the displacer - can advantageously be arranged on the drive shaft in the pressure chamber surrounding the hub on the expander side. The advantage of such an arrangement is the absolute separation of the lubricating oil from the compressed air.

If the rotor of an electric motor driving the displacer is arranged on a common drive shaft with the eccentric disk and the displacer, it makes sense that an intermediate housing is attached to the housing of the electric motor on the side of the electric motor facing away from the displacer, into which intermediate housing the one with a lubricant -Drive device provided drive shaft, and that a housing for a lubricant supply is attached to the intermediate housing. Such an arrangement with an intermediate housing is advantageous for accommodating, for example, a combined reduction and synchronization gear, which projects into the oil reservoir and is thus lubricated.

If the displacer component is guided in a known manner through a spaced-apart second eccentric arrangement, the two eccentric shafts are provided with gear wheels of the same size. These are driven and synchronized by a third gear. The third gear is preferably smaller and sits on the shaft of the drive motor. This builds small as a fast rotating electric motor. The weight of the entire compressor expander unit is therefore lower compared to the use of an electric motor which rotates at the same speed as the compressor expander.

It is advisable to design the wall of the expander-side half of the housing in the area of the outlet in such a way that, together with the outer end of the cylinder wall of the expander-side delivery space, a container for receiving lubricant is formed, this container being connected to the lubricant circuit via external lines is. Since the gases leaving the expander are at a low temperature, this arrangement of the lubricating oil container at the outer end of the cylinder wall allows the lubricant to be cooled during machine operation.

Brief description of the drawing

In the drawings, only the elements essential for understanding the invention are shown. The direction of flow of the various tools is shown with arrows. Functionally identical elements are provided with the same reference symbols in the different figures.

Fig. 1

einen Längsschnitt durch eine Verdrängermaschine gemäß dem Stand der Technik.

Fig. 2

einen Teilschnitt aus Fig. 1, vergrössert dargestellt, mit der Abdichtung der Leisten auf dem Grund der sichelförmigen Arbeitsräume;

Fig. 3

einen Querschnitt durch die Verdrängermaschine gemäss 3-3 in Fig. 1 mit dem Expansionsteil der Verdrängermaschine;

Fig. 4

einen Schnitt durch die Scheibe des Läufers der Verdrängermaschine gemäss Linie 4-4 in Fig. 1:

Fig. 5

einen Querschnitt durch den Verdichterteil der Verdrängermaschine gemäss Linien 5-5 und 5'-5' in Fig. 1;

Fig. 6

einen Längsschnitt durch eine Ausführungsvariante der Verdrängermaschine mit Antriebsmotor und Kreislauf für Schmier- und Kühlmittel;

Fig. 7

einen Querschnitt durch die Antriebswelle entlang der Linie 7-7 in Fig. 6;

Fig. 8

einen Querschnitt durch die Verdrängermaschine gemäss Linie 8-8 in Fig. 6 mit dem Expansionsteil der Verdrängermaschine und einer als Schmier- und Kühlmittelvorrat ausgebildeten Gehäusehälfte;

Fig. 9

das Prinzip der Erfindung, wobei die Expansion von radial aussen nach radial innen durchgeführt wird.

Fig. 10

das Prinzip der Ausführung gemäss Fig. 9 mit Doppelexzentertrieb und Synchronisations-Zahnräder.

Show it:

Fig. 1

a longitudinal section through a displacement machine according to the prior art.

Fig. 2

a partial section of Figure 1, shown enlarged, with the sealing of the strips on the bottom of the crescent-shaped work spaces.

Fig. 3

a cross section through the displacement machine according to 3-3 in Figure 1 with the expansion part of the displacement machine.

Fig. 4

a section through the disc of the rotor of the displacement machine according to line 4-4 in Fig. 1:

Fig. 5

a cross section through the compressor part of the displacement machine according to lines 5-5 and 5'-5 'in Fig. 1;

Fig. 6

a longitudinal section through an embodiment of the displacement machine with drive motor and circuit for lubricants and coolants;

Fig. 7

a cross section through the drive shaft along the line 7-7 in Fig. 6;

Fig. 8

a cross section through the displacement machine according to line 8-8 in Figure 6 with the expansion part of the displacement machine and a housing half designed as a lubricant and coolant supply.

Fig. 9

the principle of the invention, wherein the expansion is carried out from radially outside to radially inside.

Fig. 10

the principle of the embodiment according to FIG. 9 with double eccentric drive and synchronization gears.

Way of carrying out the invention

For an explanation of the functioning of the displacement machine, reference is made to DE-C3-26 03 462 already mentioned at the beginning. Only the machine structure and process flow necessary for understanding are briefly described below:

The compressor / expander machine as a whole is designated by 1 in FIGS. 1 and 6. The indices "a" in the reference symbols are for the compressor side; the indices "b" are used for the expander side of 1.

A spiral-shaped displacement body is arranged on both sides of the disk 2. These are strips 3a, 3b which are held vertically on the pane 2. In the example shown, the spiral itself is formed from a plurality of circular arcs adjoining one another. 4 with a hub is designated with which the disc 2 is mounted on an eccentric bearing 17. 1, 4 and 6 show the bearing 17, which is seated on an eccentric disk 23, which in turn is part of a drive shaft 24. In FIG. 4, 5 denotes an eye arranged radially outside of the strips 3a, 3b for receiving a guide bearing 25 which is mounted on a bolt 26a. This in turn is part of a guide device 49 which, for. B. consists of a rocker 56, one end of which is rotatable about the axis 50 by means of bolts 26b and bearings 27 in the housing 7a, 7b. The other end engages in the eye 5 of the rotor via the bolt 26a and the bearing 25.

According to FIGS. 1, 5 and 6, openings 6a are provided at the spiral outlet on the compressor side in the housing half 7a so that the medium can be drawn off through the central outlet 13 arranged on one side.

1 shows the machine housing 7a, 7b, which is composed of two halves and is connected to one another via fastening eyes 8a, 8b for receiving screw connections 8c. 11a denotes the delivery space on the compressor side, which is worked into the housing half 7a in the manner of a spiral slot. It runs parallel from an outer circumference of the spiral in the housing half 7a arranged low pressure inlet 12 to a pressure space 33a provided inside the housing and to the high pressure outlet 13. The delivery chamber 11a has essentially one or more approximately parallel, approximately equally spaced from each other Cylinder walls 51a, which in the present case, like the bar 3a of the disk 2, comprise a spiral. Between these cylinder walls 51a, the bar 3a engages, the curvature of which is dimensioned such that the bar 3a almost touches the inner cylinder wall 15a and the outer cylinder wall 14a, for example, at one point 21a (FIG. 5).

Fig. 2 shows an embodiment of the lateral sealing of the strip 3a with respect to the base surfaces of the spiral slot machined into the housing half 7a. This takes place e.g. by a touching sealing strip 28, which is incorporated into a groove provided in the strip 3.

The disk 2 is driven by the drive shaft 24 via the eccentric disk 23. The disk 2 is guided by the guide device 49 (FIG. 4). Depending on whether the guide device 49 consists of a rocker 56 or a guide shaft (not shown) running synchronously with the drive shaft 24, all points on the bar 3a carry out an elliptical-like or a circular displacement movement with an eccentricity "e" corresponding Deflection from. 4, the hub 4 cannot be seen, since this part of the disk 2 is shown in section. The bearing 17 with which the disk 2 is guided on the eccentric disk 23 is shown here, for example, as a roller bearing.

Due to the multiple alternating approach of the bar 3a to the inner cylinder wall 15a, respectively. Outer cylinder wall 14a of the associated delivery chamber 11a results in crescent-shaped workrooms enclosing the working medium on both sides of the ledge 3a, which are displaced by the delivery chamber 11a in the direction of the pressure chamber 33a and the central outlet 13 communicating therewith while the disk 2 is being driven. The volumes of these working spaces are reduced and the pressure of the working fluid is increased accordingly.

The arrangement of the strip 3b on the expander side of the machine is analogous to that described above. 11b denotes the conveying space on the expander side, which is also machined into the housing half 7b in the manner of a spiral slot. According to FIG. 3, it runs parallel from an outer circumference of the spiral in the housing to the low-pressure outlet 20 to an inlet provided in the housing interior, which part of the pressure chamber 33b in the Housing 7b is. The conveying space 11b likewise has essentially parallel cylinder walls 51b, which are arranged at approximately the same distance from one another and which, in the present case, like the bar 3b of the disk 2, comprise a spiral. Between these cylinder walls 14b, 15b engages the bar 3b, the curvature of which is dimensioned such that the bar 3b almost touches the inner cylinder wall 15b and the outer cylinder wall 14b during operation, for example at one point 21b each.

The bar 3b is arranged on the disc 2 so that during machine operation due to the multiple alternating approach of the bar 3b to the inner cylinder wall 15b, respectively. Outer cylinder wall 14b of the associated delivery chamber 11b results in crescent-shaped workrooms enclosing the working medium on both sides of the strip 3a. These working spaces move while the disk 2 is being driven through the conveying chamber 11b in the direction of the central outlet 20. This increases the volumes of these working spaces and the pressure of the working medium decreases in the expander part. Due to the expansion of the working medium located in the working spaces on the expander side, work is given to the bar 3b and thus the eccentric disk 23. The compression and expansion functions are thus combined on a single component, which rotates in a fixed housing 7a, 7b and consists of disk 2, hub 4 and strips 3a and 3b.

Fig. 5 shows the arrangement of the strips 3a and 3b attached on both sides of the pane 2. According to the orientation of the cutting direction 5-5 shown in FIG. 1, the direction of rotation of the drive shaft 24 with the counterweight 16a around the center of rotation 30 is clockwise. The outer edge of the pane 2 and the bar 3b of the expander part are shown in dashed lines according to section 5'-5 'in FIG. 1. For the sake of clarity, the spiral wall 51b in the housing half 7b is not shown. However, the arrangement of the bar 3a on the compressor side compared to the bar 3b on the expander side can be seen.

In Fig. 1, the drive shaft is supported with a support bearing 9a in a bearing receptacle 52a in the housing half 7a. The bearing holder 52a is connected to the housing half via supports 29a. The bearing is sealed against the pressure chamber 33a by means of a shaft seal 33a. The openings 6a are located between the supports 29a. As a result of these breakthroughs, the conveying medium brought to higher pressure can leave the compressor part. The funding can be supplied to a process that is not described here in detail.

After this process, in which no particular pressure drop is assumed, the working medium is to flow via the high-pressure inlet 19 into the inner pressure chamber 33b of the expander part on the expander side. The drive shaft is guided in the housing half 7b by means of a support bearing 9b which is supported with the housing half 7b by means of a bearing receptacle 52b with the ribs 29b. The openings 6b are located between the supports and provide access for the working medium to the pressure chamber 33b on the expander side.

The disk 2 is guided on the eccentric disk 23 via the eccentric bearing 17, onto which the hub 4 is mounted and which, for example, is opposite the pressure chambers 33a and 33b. is sealed with shaft seals 18. With 31 the center of the eccentric 23 is designated. This center is spaced from the rotation center 30 by an eccentricity "e". Counterweights 16a and 16b are attached to the drive shaft 24, which ensure a balanced running of the machine.

6 shows a variant of the compressor / expander machine with a drive motor, preferably an electric motor. The housing 66 of the motor has threaded eyes 8b 'into which screw connections 8c engage. Together with an intermediate housing 54 on the expander side and the housing halves 7a and 7b, the compressor / expander machine 1 is connected to the electric motor to form a machine.

The entry-side guidance of the working medium to be expanded in the intermediate housing 54 must take into account the fact that the working medium in the expansion part of the compressor / expander machine, viewed in the radial direction, flows from the inside to the outside; it must be fed into the center of the expansion side of the displacement machine. The schematically illustrated solution shows that the working medium enters the intermediate housing 54 at the high pressure inlet 55 and passes through openings 99 into an annular space 32. This space 32 is sealed on the side of the compressor / expander machine 1 by the shaft 24 with a support bearing 58 and on the side of the electric motor by a shaft seal 62 against the ambient pressure prevailing in the interior of the electric motor housing 63. The shaft seal 62 engages on a thickening 44 attached to the drive shaft. The annular space 32 is connected to the pressure space 33b via openings 57 in the shaft 24, so that the working medium to be expanded can reach the interior 33b of the expander part.

Carrying out the working fluid through the openings in the shaft 24 is expedient because the entire drive shaft with the rotor 64 of the electric motor is only guided with two support bearings 58, 93. Furthermore, in contrast to the embodiment according to FIG. 1, only a counterweight 16 is to be attached to the shaft 24, specifically on the expander side. In order to ensure the bending stiffness of the drive shaft 24, which is necessary for stable running of the machine, the drive shaft 24 is dimensioned with a relatively large diameter in the region of the support bearing 58. The provision of openings 57 (see also FIGS. 7 and 8) in the rigid part for the introduction of the working medium to be expanded is expedient.

The support bearing 58 is designed in the example shown in FIG. 6 as a roller bearing, on the outer ring of which a position ring 59 is attached, which in a z. B. recess in the housing half 7b and is clamped by the intermediate housing 54. The inner ring of the roller bearing 58 is in contact with the drive shaft 24 on one side on a collar 82 and on the other side a ring 83. With this arrangement, the drive shaft 24 is guided axially relative to the housing parts 7a, 7b, 54 and 66.

On the side of the electric motor opposite the compressor / expander unit 1, which essentially consists of the housing 66 and the rotor 64, a lubricant container 68 with the lubricant supply 69 is arranged. A device that generates a lubricant flow for lubricating and cooling the highly loaded eccentric bearing 17 is necessary because the compressor / expander machine is to be small in relation to the flow of working fluid being conveyed and is therefore operated at high speed. This results in the aforementioned high load on the eccentric bearing 17. The lubricant circuit is as follows.

The container 68 encloses a housing 71, which receives the support bearing 93 of the shaft 24 facing away from the compressor / expander unit. Furthermore, a lubricant delivery device 72 (not described in more detail here) is mounted in the housing 71 on the drive shaft 24 and driven by the latter. This lubricant delivery device 72 sucks the lubricant out of the supply 69 via a suction line 79 and conveys it into a space 73 under increased pressure.

In the shaft 24 common to the rotor 64 and the compressor / expander 1, an insert 75 is installed in a central bore 76, which in turn has a central delivery bore 74. This is connected to the space 73 on the lubricant supply side. On the side of the compressor / expander unit 1, the delivery bore 74 'is connected to a bore 88 arranged radially in the eccentric disk 23. The bore 88 opens at its radially outer end directly into the eccentric bearing 17 and supplies it with lubricant. In Fig. 6 this bearing is shown as a plain bearing; In the hub 4, a plain bearing bush 17 'is drawn in.

The hub 4 is with a closure 60 relative to the space 33a, respectively. the outlet 13 closed. This closure ensures that the lubricant is completely separated from the working fluid. The work equipment can thus be pumped completely without lubricants. This is in contrast to the embodiment according to FIG. 1, in which the arrangement of the shaft seals 10a and 18 on the compressor side can lead to lubricant escaping into the space 33a; Shaft seals cannot seal completely.

The lubricant can escape from the eccentric bearing 17 into the space 80 created by the closure 60. The lubricant escapes from the opposite side of the bearing 17 into an annular space 53c, which seals against the expander-side pressure space 33b by means of a shaft sealing ring 18. The lubricant collecting spaces 53c and 80 are each connected to the lubricant return channel 77 in the shaft 24 via a bore 81. This channel is created by an insert 75 which is tapered in its middle part on the outer circumference. In FIG. 7, the insert 75 is shown in section in the tapered section (section 7-7 in FIG. 6) and, in addition to the center of rotation 30 of the shaft 24, shows the delivery bore 74, the annular lubricant return flow channel 77, and the central bore 76 for the insert 75. On the side of the lubricant supply 69, a radial bore 77c is machined into the shaft 24. The lubricant can pass into an annular collecting space 45 through this bore. The collecting space 45 is machined into the housing 66 and is formed together with a shaft sealing ring 78 and the feed pump housing of the lubricant delivery device 72 and the shaft 24. A bore 90 is made in the housing 66, through which the back-flowing lubricant can flow back into the reservoir 69.

The compression of the gaseous working medium (for example air) results in an increase in temperature in the space 33a compared to the temperature prevailing in the low-pressure inlet 12. The higher temperature in the room 33a acts on the hub part 4 with closure 60 circling in this room. In addition to the primary task of lubricating the bearing 17, the lubricant also has the task the heat dissipation from the hub portion 4 with closure 60. The lubricant flowing back into the reservoir 69, as described above, must absorb its heat there, e.g. B. can deliver to the environment.

An embodiment for heat dissipation is also shown in FIG. 6.
According to the state of the art, electric motors often have a fan wheel 67 which is mounted on the shaft 24 in the present example. Through openings 65 in the housing 66, the cooling air flow 85 reaches the interior of the electric motor and, depending on the strength of the cooling air flow 85 generated by the impeller 67, experiences a more or less strong temperature increase. Provided that the fan wheel is dimensioned strong enough, there is an advantageous embodiment for the cooling of the lubricant in the reservoir 68. By deflecting the cooling air flow by means of air guiding means 84, it is guided past the cooling surfaces 70, which are attached to the container 68, and takes on further heat from the container 68.

A variant for removing the heat from the lubricant is shown in FIG. 8. The drawing schematically shows a wall part 94 of the housing 7b, which is designed such that a container 95 is formed. This container is located in the region of the outer end 98 of the cylinder wall 51 b, viewed in the direction of flow. The supply and discharge of the lubricant to and from the container 95 takes place via external lines 96, 97 (not described in more detail), which can be connected to a lubricant delivery device 72, as shown in FIG. 6. The arrangement takes advantage of the fact that the temperature decreases as the gaseous working medium expands.

When using the compressor / expander 1, for example on fuel cells, the temperature at the entry of the working fluid into the space 33b is relatively low, provided that no special devices are used which measure the temperature of the working fluid in the high-pressure inlet 19 or. 55, 33b of the expansion machine. Such devices can consist, for example, of a heat exchanger which transfers the heat of the compressed air to the Outlet 13 to the work equipment to be expanded before the inlet 19, respectively. Release 55, 33b and heat this to increase the ability to expand.

Since water is an essential oxidation product in the use of fuel cells, which enriches the working fluid before the expansion process, it can be assumed that the dew point towards the low-pressure outlet 20 is significantly lower and, depending on the initial temperature of the expansion, the freezing point is also fallen below. If no special measures are taken, ice can form in the area of the cylinder walls 98 during machine operation.

This is avoided by using the lot around the outlet 20, 98 to attach the lubricant supply 95 there. This measure is cooled on the one hand by this measure and on the other hand prevents ice formation at 20, 98.

9 shows the example of the invention in which the expansion of the working medium takes place from the radially outside to the radially inside. In contrast to the expansion shown in FIGS. 1, 3 and 6, the high pressure gas flows through an opening 55 into the high pressure space 33b. The expanded gas flows through openings 57 in the shaft 24 from the low-pressure interior of the expander part.

Of course, the invention is not limited to the machine previously shown and described. In the event that two spaced-apart eccentric arrangements are used to guide the displacer, the electric motor can also engage between two shafts with spaced axes of rotation 30 and 104 instead of on the drive shaft 24. Such an arrangement is shown in FIG. 10. For the sake of clarity, it only shows the displacer consisting of the disk 23 and the strips 3b with the wheel drive. This consists of a drive wheel 100, a wheel on the drive motor 101, and a synchronization wheel 102. 103 shows a toothing on the wheel. The identical toothing is also provided for the wheels 101 and 102 but is not shown here. The axis of the drive motor is designated by 108, that of the guide eccentric arrangement by 104. B. a known radially elastic and tangentially rigid connection 105 to the eye 106. The eye 106 has its center at 107, which circles with the eccentricity "e" around the center of rotation 104 in machine operation.

LIST OF REFERENCE NUMBERS

1

Compressor / expander

2

Disc,

3a, 3b

Last, displacer

4

hub

5

eye

6a

Breakthrough in 7a

6b

Breakthrough in 7b

7a, 7b

housing half

8a, 8b, 8b '

fastening eye

8c

fixing screw

9a

Support bearing for 24 in 7a

9b

Support bearing for 24 in 7b

10a, 10b

Shaft seals from 24

11a

Funding area in 7a

11b

Funding area in 7b

12

Low pressure inlet

13

High-pressure outlet

14a

Cylinder wall of 11a, outer

14b

Cylinder wall from 11b, outer

15a

11a cylinder wall, inner

15b

11b cylinder wall, inner

16,16a, 16b

Balance weights on 24

17.17 '

Eccentric bearings between 4 and 23

18

Shaft seals from 23

19

High pressure inlet

20

Low-pressure outlet

21a, 21b

Sealing line in 7a, 7b of 11a, 11b

22

rib

23

eccentric

24

drive shaft

25

Lead bearing in 56 on 26a

26a

Guide pin in 2nd

26b

Guide pin between 7a, 7b

27

Guide bearing in 56 on 26b

28

sealing strips

29a, 29b

rib

30

Center of rotation of 24

31

Center of 23

33a

Pressure chamber in 7a (compressor side)

33b

Pressure chamber in 7b (expander part)

32

Annular space between 58 and 62

44

Waistband for 62 on 24

45

Annular collecting room

49

guide means

50

Center axis of 26b

51a, 51b, 51b '

Last in 7a, 7b

52a, 52b

Inventory in 7a, 7b

53a

Warehouse interior of 9a

53b

Warehouse interior of 9b

53c

Warehouse interior from 17th

54

intermediate housing

55

High pressure inlet

56

wing

57

Breakthrough in 24

58

storage

59

Clamping ring between 54 and 7b

60

Locking disc on 4th

61

High-pressure space

62

Shaft seal between 61 and 63

63

Electric motor interior

64

Electric motor rotor

65

Breakthroughs in 66

66

Housing of the electric motor

67

Fan wheel on 24

68

Housing of 69

69

Lubricant stock, lubricants

70

cooling surface

71

bearing housing

72

Feed pump for 69

73

Print room from 69

74.74 '

Pressure line for 69 in 24

75.75 '

Use in 24

76

Hole in 24

77,77c

Lubricant return channel in 24

78

Shaft seal 24, rear

79

Suction line for 69

80

Low pressure room between 60 & 23

81

Low pressure lines in 23 to 77

82

Shoulder on 24 for 58

83

Position ring on 24 for 58

84

Guide for 85

85

Cooling air flow

86

Screw connection for 68

87

Filler neck for 69 with lid

88

Connection between 74 & 17 in 23

89

Screw connection from 71 to 66

90

Low pressure drain in 66 to 69

93

Storage of 24 in 71

94

Outside wall of 95

95

lubricant space

96

Lubricant return

97

lubricant flow

98

Final batch of 51b

99

Breakthrough in 54

e

Eccentricity; Distance in the radial direction between the axis of rotation 30 of FIG. 24 and the center 31 of FIG. 23.

100

Drive wheel on drive shaft 24

101

Drive wheel on drive motor

102

Synchronization wheel on a second eccentric arrangement

103

gearing

104

Center of rotation of the second eccentric arrangement

105

Radially elastic, tangentially rigid connection to 23

106

Eye at 105

107

Center of the second eccentric

108

Rotation center of the side-mounted drive motor

109

Inner end of 3b in Fig. 10

Claims (9)

1. Displacement machine for compressible media with two spiral feed chambers (11a, 11b) which are arranged opposite each other in a fixed housing (7a, 7b), and a displacement body (2-4), consisting essentially of a central disc (2) and of spiral strips (3a, 3b) which are attached to each side of the central disc (2), engage in the feed chambers (11a, 11b) and which are held in an eccentric manner in relation to the housing (7a, 7b), so that during operation each point on the strips (3a, 3b) executes a circular or elliptical movement, depending on the configuration of a guiding device (49), said movement being limited by the cylinder walls of the feed chambers (11a, 11b), and so that the curvature of the strips (3a, 3b) is dimensioned such that the strips (3a, 3b) almost touches the inner cylinder walls (15) and the outer cylinder walls (14) of the corresponding feed chambers (11a, 11b) on in each case at least one sealing line per strip (3a, 3b), said sealing line advancing continuously during operation; wherein one feed chamber (11a) is configured for compressing a working substance and the other opposed feed chamber (11b) for expanding said working substance, the cylinder walls (14, 15) of the feed chambers (11a, 11b) and the strips (3a, 3b) engaging in the feed chambers (11a, 11b) consisting essentially of successive circular arc segments whose radii in the compression-side feed chambers (11a) and strips (3a) are essentially decreasing in size, when viewed in a direction of rotation, and the radii of the circular arc segments in the expansion-side feed chambers (11b) and strips (3b) are essentially increasing in size, when viewed in the same direction of rotation; wherein the compression-side feed chamber (11a) extends from a radially outwardly arranged low-pressure inlet (12) to a radially inwardly arranged high-pressure outlet (13), and wherein, in order to guide the displacement body (2-4) in relation to the housing (7a, 7b), an eccentric arrangement is provided which essentially consists of a drive shaft (24) and of an eccentric disc (23) arranged thereon, characterized in that the expansion-side feed chamber (11b) extends from a radially outwardly arranged high-pressure inlet (55) to a radially inwardly arranged low-pressure chamber.
2. Displacement machine according to Claim 1, characterized in that the hub (4) of the disc (2) is surrounded on its outside of the compression side by a high-pressure chamber (33a), in that the hub interior is closed off in an airtight manner from this high-pressure chamber (33a) by means of a closure piece (60), and in that a counterweight (16) - provided to compensate the eccentric movement of the eccentric disc (23) and of the displacement body (2-4) - is arranged on the drive shaft (24) in the expansion-side pressure chamber (33b) surrounding the hub (4).
3. Displacement machine according to Claim 1 or 2, characterized in that the expansion-side half (7b) of the housing is connected directly to a housing (66) of an electric motor via a screw fitting (8a, 8b, 8b', 8c).
4. Displacement machine according to Claim 3, characterized in that the rotor (64) of the electric motor is arranged on a common drive shaft (24) with the eccentric disc (23) and the displacement body (2-4).
5. Displacement machine according to Claim 4, characterized in that, on the side of the electric motor facing away from the displacement body (2-4), an intermediate housing (71) is attached to the housing (66) of the electric motor, into which intermediate housing protrudes the drive shaft provided with a lubricant feed device (72), and in that a housing (68) for a lubricant reservoir (69) is secured on the intermediate housing (71).
6. Displacement machine according to Claim 5, characterized in that the drive shaft (24) has a bore (76) for receiving an insert (75) which is likewise of hollow configuration and which in the central area is recessed on the outer surface, resulting in two axial lubricant guide channels (74, 77) about the centre of rotation (30) of the drive shaft (24), of which a high-pressure channel (74) is connected on the one hand to the lubricant feed device (72) via a pressure chamber (73) and is connected on the other hand to an eccentric bearing (17) via a chamber (74') and a bore (75') in the eccentric disc (23).
7. Displacement machine according to Claim 6, characterized in that, for return of the lubricant from the eccentric bearing (17) into the lubricant reservoir (69), a low-pressure chamber (80) and a bearing interior (53c) respectively are provided on either side of the bearing and these are in each case connected via a bore (81) in the eccentric disc (23) to the lubricant return channel (77) arranged in the drive shaft (24).
8. Displacement machine according to Claim 5, characterized in that a blower wheel (67) for feeding a cooling air stream (85) is arranged on the drive shaft (24) inside the housing (66) of the electric motor, this cooling air stream being directed via apertures (65) in the housing (66) through the interior (63) of the electric motor and via air guide means (84) onto cooling surfaces (70) which are arranged on the housing (68) of the lubricant reservoir (69).
9. Displacement machine according to Claim 1, in which the displacement body (2-4) is guided by a separate second eccentric arrangement, characterized in that the two eccentric shafts bear gearwheels (100, 102) of identical size which are driven and synchronized by a third gearwheel (101), said third gearwheel preferably being smaller and being arranged on the shaft of a drive motor, and the drive motor being designed as a rapidly rotating electric motor.