FI88539C - Method and apparatus for transporting solids from one pressure to another - Google Patents

Description

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METHOD AND APPARATUS FOR TRANSFERRING SOLID FROM ONE PRESSURE TO ANOTHER PRESSURE

FRAMEWORK FOR TRANSPORT OF FAST MATERIAL FRENCH ETT TRYCK TILL ETT ANNAT

The invention relates to a method and apparatus for feeding or discharging solids from one pressure to another. The invention relates in particular to a feeding or unloading device formed by a housing and a rotor rotatably fitted thereto. The housing is provided with a solids supply port connected to the inlet channel and a solids outlet port connected to the outlet channel. At least one closing chamber with a piston is arranged in the rotor.

The invention also relates to a method for supplying or discharging a solid with the device according to the invention in stages from one pressure to another. The various steps of the method comprise - a first transfer step of rotating the rotor 15 to a position such that the sealing chamber communicates with the inlet passage through the solids supply port; wherein the rotor is rotated to a position such that the sealing chamber is in communication with the outlet passage through the solids outlet; and - the emptying step of moving the piston of the sealing chamber outwardly in the sealing chamber and draining solids from the sealing chamber through the solids outlet to another pressure.

· The invention can be advantageously applied to the supply of fuel to a pressurized space in pressurized combustion or gasification plants. The invention is particularly well suited for supplying biofuel such as bark and peat to a pressurized space and also for supplying moist fuel.

2 8 5?: 9 5 The invention can also be applied in pressurized combustion or gasification processes to remove ash from a pressurized space to normal pressure.

In pressurized combustion or gasification plants, the fuel and possibly other substances fed to the combustion chamber must be fed from a storage tank at normal pressure to high pressure. The combustion chamber pressure can vary between 1-100 bar. With conventional feeders, feeding is not possible.

15

Fuel can be fed into the pressurized space by means of a briquette dropper. However, the briquettes have to be decomposed before the combustion or gasification step, e.g. with a grinder. The briquettes easily form too hard, so that the 20 grinding steps become difficult. In addition, the electrical power required by the briquette press is considerable.

The best known and most common way to feed fuel to a pressurized space is to feed with a pressurized shut-off feeder. 25 However, the problem with shut-off feeders is the tightness of the feeders, the risk of vaulting and the pressure limitation. In the shut-off feeder, the shut-off chamber is alternately connected to the fuel storage tank and alternately to the fuel chamber in the pressurized state. 30 fuels at a time are introduced into the pressurized space by the volume of the shut-off chamber. To ensure fuel supply, the shut-off chamber must be relatively large, which increases the cost of the device. As the shut-off chamber moves empty from the combustion chamber to the storage tank, it carries with it the volume of the shut-off chamber to the storage tank 35. This can be very dangerous and cause the fuel to ignite already in the storage tank. Particularly airy dry and dusty biofuels such as peat are extremely flammable.

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In shut-off feeders, such as tray feeders, the material to be fed is easily vaulted. The problem then becomes poor emptying of the tray when the feeder turns to emission-5. The same vaulting problem and uneven silo emptying have been found in storage silos. In the shut-off feeders, pressurized gas always travels out in empty compartments, which is difficult to handle and the loss of pressurized gas easily becomes large, which increases the cost of pressurization.

The tightness of the feeders themselves is also important. It must be possible to supply fuel to the pressurized space without the pressure being released or harmful gases escaping from the pressurized space through the feeder. Airy or loose fuel, for example in screw feeders, cannot form a tight barrier to hot gases coming from a pressurized space. The possibly refluxing gases can thus ignite the fuel already in the feeder 20 or in the fuel silo.

With the plug screw feeder, the fuel can be compacted somewhat so that the supply to a pressure of approx. 4 bar is successful. However, in plug screw feeders, the fuel may form a plug that partially or completely clogs the feeder. On the other hand, if the material to be fed is peat with a humidity> 65%, no plug is formed at all, but the material decomposes and feeding is not possible. It is not possible to supply a high pressure> 10 bar with the plug screw 30, even if the fuel is drier. When, for example, the moisture of milled peat is about 50-75%, it cannot be satisfactorily fed to a combustion or gasification chamber pressurized by known equipment. The electrical power required for the plug screw is also considerable.

V 35

Finnish patent application FI 864545 proposes a pneumatic conveying system for bringing fuel into a pressurized space. The feed device comprises a closed 4 "8579 housing with a rotor and a material space in the form of at least one funnel arranged therein. The rotor is movable by a drive. The housing and rotor have an inlet for fuel at the top and an outlet at the bottom. In the funnel-shaped material compartments, the fuel is vaulted very easily. remaining in the material space is also detrimental during refilling and may prevent the fuel from being evenly distributed in the material space.

Finnish patent application FI 895835 discloses a supply device of the same type in which the risk of vaulting has been eliminated and the gas has been prevented from remaining in the substance space. The device 20 comprises a cylindrical housing and a rotor fitted therein, in which two or more small cylindrical closure chambers are formed. The closure chambers open at one end of the housing, which is sealed with a closure plate. The opening plate is provided with two openings - an inlet and an outlet - so that the openings of the closing chamber alternately meet the inlet and the outlet as the rotor moves. A piston is connected to one end of the closure chambers, with which the volume of the closure chamber can be increased when the substance is fed into the closure chamber and the closure chamber 30 can be reduced when emptying. The piston rods are arranged to protrude out of the rotor as the volume of the closure chamber increases.

It is an object of the present invention to provide a better method and apparatus for transferring a solid from one pressure to another than those described above.

The object of the invention is, for example, to provide a method and a device with which a solid can be fed into a pressurized space even when the pressure difference is large.

It is also an object of the invention to provide a simple, safe and reliable solids transfer device.

To achieve the above objects, the method according to the present invention is characterized in that during the transfer steps the rotor is rotated in the housing 10 about a common axis of the housing and the rotor so that - the curved outer surface of the rotor closes both the solids feed opening and the outlet and - the curved outer surface the inner surface substantially preventing the pressurized gas 15 from flowing from the higher pressure to the lower pressure.

Thus, with the method according to the invention, it is possible, for example, to supply fuel from normal pressure to a pressurized furnace without hot pressurized gases escaping from the furnace into the fuel inlet duct. The solids transfer barrier in the rotor communicates with the non-pressurized fuel inlet during the feed phase and with the pressurized hot flue gas during the discharge phase. During the first transfer step, with the closure chamber running empty from the solids outlet to the solids feed port, the closure chamber piston is in its outermost position and slides tightly along the curved wall of the housing. During the second transfer stage, the sealing chamber, which is now filled with solids, passes the solids along the housing wall from the inlet to the outlet. During the transfer steps, both the solids inlet and the outlet are closed so that the outer surface of the rotor running in the housing covers the openings and prevents the flow of gases through the openings.

35

The feeding or unloading device according to the invention is characterized in that - the housing has a curved, e.g. cylindrical, truncated 6 8 519 conical or at least partially spherical inner surface in which the solids supply opening and outlet opening are arranged, - the rotor has a correspondingly curved, e.g. 5 rin, cone or at least partially spherical outer surface into which the closure chamber arranged in the rotor opens and - the rotor is arranged in the housing concentrically with the housing so that the curved curved surface of the rotor follows the curved surface of the housing and prevents .

According to a preferred embodiment of the invention, the feed device comprises a rotor in which a radially cylindrical closing chamber is arranged on the circumference of the rotor, so that the axis of the cylinder is in the radial direction of the rotor. The opening formed in the circumference of the rotor of the cylindrical closure chamber is preferably of the same size and shape as the inlet and outlet openings 20 arranged in the housing.

The rotor is preferably provided with two cylindrical closure chambers of the same diameter, one on each opposite side of the rotor. Correspondingly, the inlet and outlet openings arranged in the housing are arranged on opposite sides of the housing 25. In this way, one closing chamber can be filled at the inlet while the other closing chamber is emptied at the outlet. The rotor is rotated 180 * about its axis during the transition phases so that the closing chamber moves from the feed opening to the outlet opening and vice versa.

The invention can also be applied to a supply device in which more than two closing chambers are arranged in the housing. However, the closure chambers are preferably in an even number and are located in pairs with the same rotor diameter.

According to a preferred embodiment of the invention, the cylindrical closure chamber has a piston having a diameter substantially the same as the inner diameter of the cylindrical closure chamber. The piston is, for example, sealed with a piston ring against the wall of the closure chamber. During the first transfer stage, the piston is in the upper position, i.e. in the second extreme position, working towards the circumference of the rotor, so that the volume of the closing chamber is minimal, i.e. practically almost non-existent. During the filling phase, the piston moves towards the bottom of the cylinder to the second extreme position so that the volume of the sealing chamber increases and the sealing chamber is filled with a suitable amount of 10 solids. Thereafter, during the second transfer stage, in which the rotor rotates 180 ° about its axis, the piston is in the retracted position. During the emptying phase, the piston moves upwards towards the circumference of the rotor while emptying the closing chamber.

15

When there are two closing chambers with the same rotor diameter, the pistons in both closing chambers can preferably be arranged on the same piston shaft, whereby the movement of the pistons is synchronized so that when the second piston moves upwards the other piston moves towards the bottom and vice versa.

The pistons can, of course, be arranged on different piston rods, so that their movements are not interdependent. Then, for example, only a part of the volume 25 of the closure chamber can be filled with solid and the piston can only be partially retracted into the closure chamber and not all the way to the bottom, because the movement of the piston is not dependent on the movement of the other piston.

In the housing, the supply opening is preferably arranged in the upper part and the outlet opening in the lower part, whereby gravity can be utilized in the filling phase. During the filling phase, the rotor is placed in such a position that the opening of the closing chamber on the circumference of the rotor is directly below the feed opening, whereby the solid falls from the outlet directly under the effect of gravity 35 into the closing chamber. As the piston moves downwards, a vacuum is created in the closing chamber, which ensures that it is filled with solid matter. Accordingly, gravity can be utilized in emptying the closure chamber.

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During the rotation of the rotor, the opening of the filled closing chamber is closed as the opening slides tightly along the wall of the housing, and no gas or solid can escape from the closing chamber. The rotation of the rotor stops when the opening of the closing chamber moves to the outlet opening. During the emptying phase of the closing chamber, the piston moves towards the opening in the closing chamber while the solid passes through the outlet into the pressure channel. The removal of solids from the sealing chamber takes place by the action of 10 pistons and gravity.

A great advantage of the method and device according to the invention is that the device can ensure the tightness of the closing chamber during feeding. Hot or toxic gases 15 must also not leak back from the pressurized space, e.g. into a fuel-filled space. Especially if a conical housing and a conical rotor are used, the gap between the housing and the rotor can be adjusted to the desired size even at a later stage. In this way, the increase in the gap caused by wear, e.g. Also, no solid can escape from the sealed device outside the supply system.

For conventional solid fuel pressurization systems, e.g. Lock-hopper equipment and closing feeders are characterized in that they leak out through the discharge gas so much that they affect the efficiency of the process. Leakage occurs in these as a backflow with an empty sealing chamber on the inlet side of the solid 30. The leak must be compensated by supplying a corresponding amount of gas to the pressure by means of a gas compressor. If the gas to be replaced is, for example, nitrogen, as is common in gasification processes, the cost involved can be considerable. With the device according to the invention, such leakage is made very small, because gas leakage occurs in practice only through the sealing member.

An essential advantage of the solution according to the invention is still in the 9 May 3 '9 that the feeder will never have direct contact with the solids from the inlet and outlet. The device according to the invention is "foolproof", there is a power failure, adjustment or connection error is unable to provide a device of direct 5 Contact between the pressurized and non-pressurized side. the device does not have a valve between the pressurized and non-pressurized side, which could accidentally be left open.

A great advantage of the method and device according to the invention is also that they can supply peat or other airy biofuel to a pressurized fluidized bed gasifier or incinerator. The method according to the invention can thus be used for feeding fuel to a pressurized combustion plant or carburetor. Supply 15 is also trouble-free with a large pressure difference, up to more than 20 bar.

Advantages may also be that the supply method according to the invention also does not present a risk of fuel vaulting, since the volume of the sealing chamber during filling is changed and thus a movement in the fuel is provided, and that in the supply method or device the fuel is not compressed. important for further processing.

25

In addition, it could be mentioned that the method according to the invention results in efficient use of time. In the device, the feed cycle and the discharge cycle can be arranged to take place during one piston movement at the same time. When one closure-30 chamber fills, the other is emptied. The capacitance of the device is large.

; The invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 shows a schematic sectional view of a feeding device according to the invention at the end of the filling and emptying step;

Fig. 2 shows a section along the line A-A in Fig. 1; ··· Ρ, ς 7 g ίο ’° 5 '

Figure 3 shows the feeder during the transfer phase;

Figure 4 shows the feeder at the beginning of the filling and emptying phase and

Figure 5 shows the feeder during the filling and emptying step 5.

The feed device 10 according to Figures 1 and 2 comprises a rotor, i.e. a moving part, and a stator, i.e. a fixed part. The fixed part comprises a cylindrical housing 12 having a curved inner surface 13 and having a supply opening 14 connected to the solids inlet duct 15 and an outlet opening 16 connected to a discharge duct 11 connected to the inlet duct by a fuel feeder, e.g. The outlet is connected on the discharge side of the feed-15 device, e.g. to a pressurized fuel silo, which is not shown in the figure.

The movable part is formed by a cylindrical rotor 18 with a curved outer surface 19 arranged concentrically in the housing. A very narrow gap 17 is formed between the curved inner surface 13 of the housing and the curved outer surface of the rotor. Two cylinders 20 and 22 are radially arranged inside the rotor. there are pistons 24 and 26. The cylinders are arranged radially in the rotor 25 of the same diameter so as to extend from the curved circumference of the rotor close to the center of the rotor. The pistons are arranged concentrically on the cylinders and connected by a common piston rod 32 so that when the second piston is in the outer extreme position at the top of the cylinder, i.e. at the circumference of the rotor 30, the other piston is in the inner extreme position at the bottom of the cylinder. The pistons can be moved in the cylinder, e.g. hydraulically, which is not shown.

35 The cylinders 20, 22 form sealing chambers 28 and 30 which transfer solids from unpressurized to pressure in the feeder. The sealing chamber 30 is not shown in Figures 1-4 because the piston 26 in the cylinder 22 is in its outermost position and the sealing chamber li 8 5 ?. 9 volume is therefore non-existent. The closure chamber is only shown in Figure 5, where it is being filled. In some embodiments, there may be more than two closure chambers, but they preferably always operate in pairs.

5

Cylinders And thus the closing chambers are open at their circumferential end of the rotor. The closure chamber 28 has an opening 34 on the circumference of the rotor and the closure chamber 30 has an opening 36, respectively. The pistons 24 and 26 close the other end 10 of the closure chambers and limit the volume of the closure chambers. The pistons are sealed to the cylinder walls, e.g. with piston rings 38.

In the feeding step shown in Figures 1 and 2, the opening 34 of the second sealing chamber 28 communicates directly with the supply opening 15 14. The opening 36 of the second sealing chamber 30 communicates directly with the outlet 16, respectively. In the sealing chamber 28 the piston 24 is pushed into its inner end position and filled with solid. pressure. Correspondingly, in the closure chamber 30, the piston 26 has moved to its outer position 20 and the chamber has been emptied so that there is no solid to be fed in the chamber. In Figure 1, the piston 24 is at the bottom of the cylinder 20 and the piston 26 at the top of the cylinder 22.

After the closing chamber 28 has been filled and the closing rotor 18 has been emptied, the rotor 18 is rotated 180 ° about its axis so that the opening 34 of the closing chamber 28 moves from the supply opening 14 to the outlet opening 16. Correspondingly, the opening 36 of the closing chamber 30 moves from the outlet opening 16 to the supply opening 14. 30 Rotor movement provided by an actuator not shown in the figures.

Figure 3 shows the closure chamber 28 during the transition phase, with the closure chamber moving from the filling step to the feed ports 35 to the outlet 16 and the solids moving from the unpressurized state to the pressurized state in the closure chamber. During the transfer phase, the openings 34 and 36 of both closure chambers 28 and 30 are closed. The rotor 18 is tightly 12, · C -: ..

arranged in the housing 12 so that the circumferential ends of the cylinders slide along the inner surface of the housing during the rotational movement of the rotor. The curved outer surface 19 of the rotor 18 and the curved outer surface 27 of the piston 26 as well as the curved inner surface 13 of the stator 5 act as sealing surfaces preventing pressure from entering the non-pressurized side of the outlet 16 from the discharge side 16 to the supply port 14.

If the rotor and stator are made conical, the clearance or gap 17 between them can also be adjusted, thus ensuring that the sealing surfaces actually prevent the leakage of pressurized gas from the pressurized outlet to the unpressurized supply shaft 15 through the gap. By pressing the piston 24 or 26 of the empty sealing chamber towards the curved surface 13 of the stator 15, sealing is also ensured at the empty sealing chamber. The gap 17 is made as small as possible and can be sealed, if desired, e.g. with a labyrinth seal or other conventional seals attached to the rotor.

20

In the embodiment shown in the figures, the rotor 18 rotates 180 ° between the filling step and the emptying step. In this case, the cylindrical closing chambers 28 and 30 change their position relative to the inlet opening 14 and the outlet opening 16 25. When the housing has rotated 180 ° and reached the end position, a simultaneous movement of the pistons, but in a different direction from the previous movement, takes place again. In the emptying phase, the piston moves in the closing chamber 28 towards the circumference and the closing chamber is emptied of fuel. In the second chamber 30, the piston moves inwards and the chamber is filled. Thereafter, the rotor 18 again starts to perform a 180 * movement. Fig. 4 shows the feeding device in the stage where the rotor has just made a 180 "movement, but has not yet had time to start the emptying and filling phase. Fig. 5 shows the feeding device 35 during the emptying and filling phase.

The supply opening 14 is arranged in the uppermost curved part of the horizontal cylindrical housing so that during the filling phase the fuel I i 13 '8579 drains from the filling shaft 15 downwards into the open closing chamber 28, which is in its highest position during filling. When a solid falls by gravity into the closure chamber, it is not compressed in the closure chamber and is thus also more easily removed from the closure chamber during the emptying phase. In some processes, it is preferred that the solid not be compressed so that the substance retains its original properties for the next process step, e.g. drying.

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Alternatively, it is conceivable that the substance to be fed in the feeding step is intentionally compressed, e.g. by forced feeding into the sealing chamber, if it is seen as advantageous for the next process step.

15

The solid can be fed into the sealing chamber as a forced feed on a dose basis, in which case the feed pipe or feed hopper at the feed opening is generally kept empty and only a suitable amount of solids is forced into the sealing chamber 20 during the filling step. Alternatively, the solid is fed so that the feed pipe or hopper is always full. Forced fuel supply can be achieved, for example, with a screw conveyor. If gravity cannot be utilized in filling the closure chamber, the filling 25 can be handled by forced feeding.

In the solution according to the figures, the fuel is emptied from the sealing chamber using gravity and the movement of the piston, whereby the movement of the piston effectively empties the sealing chamber.

In the same rotor, several closing chambers can be arranged side by side in the direction of the rotor axis, which are filled and emptied simultaneously. In this case, several adjacent supply and discharge connections must also be arranged in the housing 35, respectively.

In the preferred embodiment shown in the figures, the horizontal cylindrical feeder is shown with the feeder inlet 14 being arranged in the upper part of the housing and the discharge opening 16 in the lower part of the housing. However, the feeder can also be positioned so that the cylindrical housing 5 is arranged in a vertical position, whereby the feed and discharge openings are in the same horizontal plane. In this case, the closing chambers arranged in the rotor also move horizontally and their filling must be handled, for example, by forced feeding.

In the embodiment shown in the figures, the stator or feeder housing 12 is cylindrical, but may just as well be e.g. conical or partially spherical. The rotor must then be conical or spherical, respectively.

15

In the embodiment shown in the figures, the closure chambers are shown in the shape of a cylinder. The cross-section of the closing chambers can be of other shapes, e.g. elliptical, long rectangular or even square. Preferably, however, it must be possible to use a piston or other means for limiting the volume of the closure chamber when filling and emptying them.

An essential thing in the operation of the feeder is that the volume of the sealing chamber after emptying is at a minimum, preferably zero, so that no pressurized gas can pass with the sealing chamber from the outlet to the unpressurized side. Maintaining the pressure is usually expensive because it often has to be carried out using an inert gas, e.g. nitrogen or carbon dioxide, and maintaining the pressure, i.e. supplying the gas back to the pressure, requires a compressor which consumes electricity.

According to the invention, the volume of the closure chamber is kept close to zero during the transition phase from the emptying phase to the filling phase and is gradually increased only when the chamber is filled. This also avoids unnecessary gas in the sealing chamber. Excess air would move from the shut-off chamber to the is -: 8 57 9 process. Excess air, the amount of which cannot be adjusted, is not advantageous for the further process.

The invention is not intended to be limited to the embodiments 5 described above, but can be modified and applied within the scope of the inventive idea defined by the appended claims.

Claims (15)

A method of incremental feeding and discharging of solid material from one pressure to another with an inlet and outlet device comprising a housing and a rotor arranged in this rotatable housing, which is provided with an inlet opening for the solid material connecting to an inlet duct, and a discharge opening 10 for the solid material which communicates with an outlet duct, in which rotor is provided with at least one lock chamber provided with a piston, and which method comprises - a first conveying step, wherein the rotor is rotated in a position where the sluice chamber communicates with the inlet duct through the inlet opening of the solid material, - an inlet step, wherein the piston of the sluice chamber is displaced inwardly in the sluice chamber and solid material is fed from the inlet duct through the inlet opening of the solid material - other transport steps, wherein the rotor is rotated in a position, d the lock chamber is in communication with the outlet duct through the discharge opening for the solid material, and - a discharge step, wherein the piston of the lock feeder is displaced leaking in the lock chamber and solid material is emptied from the sluice chamber through the outlet opening for the solid check duct. that the rotor during the transport steps is rotated in the locking chamber around the common axis of the housing and the rotor so that - the curved outer surface of the rotor during the transport stage closes both the inlet opening and the outlet opening for the solid material and that - the curved outer surface of the rotor follows the curved outer surface of the housing. , whereby pressurized gas is substantially prevented from flowing from the higher pressure to the lower pressure. Method according to claim 1, characterized in that. 5, solid material is fed with the feed device in a pressurized space. Method according to claim 1, characterized in that. that the rotor, in which two lock chambers are arranged radially of the same diameter, one on each side of the rotor, during the transport step is rotated 180 e about its axis to move the lock chamber from the solid orifice inlet to the solid orifice opening. 15 Method according to claim 3, characterized in that. that the lock chambers arranged in the rotor are filled and emptied alternately, so that when one lock chamber is filled, the other is emptied. 20 Method according to claim 3, characterized in that. that the pistons arranged in the rotor radially of the same diameter are displaced by the same piston rod, so that when the coif in the one sluice chamber moves toward the periphery, the coif in the other sluice chamber moves towards the center of the rotor. . ···. Method according to claim 1, characterized in that. that the solid material is fed from an inlet passage located above the rotor 30 in the sluice chamber at least partially under the influence of gravity. Process according to claim 2, characterized in that. that with the feed device peat or other biofuel is fed. 22 C 8 5 3 9 An input and output device 10) for input into an outlet channel (11) or output of solid material from one Inlet channel (15) from one pressure to another, said input and output device comprising a housing (12) and a rotatably disposed rotor (18), wherein - in the housing there is provided an inlet opening (14) for the solid material which joins 1 connection with the inlet channel (15), and an outlet opening (16) for the solid material which supports 1 connection with the outlet duct (11) and the rotor (18), a lock chamber (28, 30) is provided with a piston (24, 26) characterized by it. that the 15. house has a curved e.g. cylindrical, frusto-conical or at least partially spherical inner surface (13), in which a feed opening (14) and a solid material discharge opening (16) are provided, - the rotor (18) has a corresponding curvature, e.g. A cylindrical, frusto-conical or at least partially spherical outer surface (19), against which the lock chamber (28, 30) opens and the rotor is concentrically arranged in the housing, so that the curved surface of the rotor follows the curved surface of the rotor 25 and prevents the pressurized gas flows from the inlet port to the inlet port or from the inlet port to the outlet port. 9. An input and output device according to claim 8, characterized in that. that the curvature of the curved outer surface (19) of the rotor is substantially the same as the curvature of the curved inner surface (13) of the housing. 10. An input and output device according to claim 8, characterized in that. that a cylindrical lock chamber (20, 22) is provided in the rotor, the shaft of which is parallel to the rotor's radle and whose end (34, 36) facing the rotor is open. 11. An input and output device according to claim 10, characterized in that. that in the lock chamber is provided a piston (24, 26) whose end (27) facing the rotor is curved and that the curvature of the end of the piston is substantially the same as the curvature of the lower surface (13) of the housing. 12. An input and output device according to claim 8, characterized in that. that in the rotor are arranged radially of the same diameter two cylindrical lock chambers (20, 22), the ends of which open to opposite sides of the rotor. 13. An input and output device according to claim 12, characterized therein. the pistons (24, 26) arranged in each lock chamber are joined to a piston rod (32) such that when one of the coifs is in its outer end position at the periphery of the rotor, the other coif is in its other end position in the bottom of the lock chamber . *: 25 14. An input and output device according to claim 8, characterized in that. that the opening chamber (34, 36) of the lock chamber is substantially the same and of the same shape as the inlet opening (14) and the outlet opening (16). 15. An input and output device according to claim 8, characterized in that. that the inlet opening (14) and the outlet opening (16) are arranged on opposite sides of the housing.