Rotary valve for bulk material and protection system with such a rotary valve

Abstract

A rotary valve for bulk material comprises a housing (3) having an interior space (4) with an inlet opening (35) and an outlet opening (36), side covers (21, 22) which delimit the interior space (4) at the front, a rotary wheel (7) which is arranged in the interior space (4) so as to be drivable for rotation about a longitudinal axis (8) and which is held on the side covers (21, 22), and a stopping unit (16) for deliberately stopping a rotational movement of the rotary wheel (7), the stopping unit (16) interacting with the rotary wheel (7).

Description

The invention relates to a cellular wheel lock for bulk material and to a protection system with such a cellular wheel lock.According to DIN EN 15089:2009-07 "explosion decoupling systems" this is understood to mean protection systems which prevent the propagation of an explosion pressure wave and a flame or only a flame via connecting pipes or connecting channels into other parts of the apparatus or system regions. According to this standard, cellular wheel locks are understood as passive explosion decoupling devices, the effectiveness of which on flame penetration safety and explosion resistance must be proven separately.In the event of an explosion, a rotary drive of a rotary feeder can be switched to the zero current state. It has been found that the cellular wheel continues to rotate in the non-energized state, so that there is the risk that after explosion a pressure wave and / or a flame passes through the cellular wheel lock, that is to say passes from one side of the cellular wheel lock through it to the other side of the cellular wheel lock. Studies have shown that, in the event of uncontrolled follow-up of the star feeder, the star feeder typically continues to rotate at least three star feeder chambers. Depending on the size of the rotary feeder, the follow-up time is between 1 s and 3 s.The invention is based on the object of increasing the safety in a protection system in that, in particular, it is prevented that a pressure wave and / or a flame unintentionally propagates through a cellular wheel lock in the event of an explosion.This object is achieved according to the invention by a rotary feeder with the features specified in claim 1 and by a protection system with the features specified in claim 10.The core of the invention is that a cellular wheel sluice for bulk material comprises a stopping unit which effects a targeted stopping of a rotational movement of a cellular wheel of the cellular wheel sluice. The stopping unit can be actuated, in particular switched, in a controlled manner. In particular, the stopping unit brakes and / or blocks the rotational movement of the cellular wheel. The stopping unit acts in particular actively. In particular, friction of the cellular wheel, in particular of the cellular wheel shaft, in rotary bearings of the cellular wheel lock provided for this purpose and / or on seals which in particular frictionally abut on the cellular wheel shaft is not a braking effect caused by the stopping unit.The cellular wheel sluice comprises in particular a plurality of stopping units which can in particular be activated independently of one another. In this way, it is possible in particular to initially activate a first stopping unit for stopping the rotational movement of the cellular wheel. If the stopping does not take place or at least does not take place in good time, at least one additional stopping unit can be actuated. The additional stopping unit is in particular embodied differently from the first stopping unit. This cellular wheel lock enables increased safety due to the redundancy of the stopping units.The rotary feeder comprises a housing having an interior space, an inlet opening and an outlet opening. The rotary feeder is in particular designed as a discharge feeder or as a blow-through feeder. In the rotary feeder, an inlet shaft is arranged at the inlet opening and an outlet shaft is arranged at the outlet opening. The interior is bounded at the end by side covers. In the interior, the cellular wheel is arranged rotatably drivable about a longitudinal axis. The cellular wheel is held on the side covers and in particular mounted in the side covers, in particular mounted rotatably.It has been recognized that an undesired further rotation of the cellular wheel, in particular also after a switch-off of a rotary drive of the cellular wheel, can be reduced and in particular prevented by means of the stopping unit. A stopping distance of the cell wheel, i.e. a stopping rotational movement which the cell wheel performs during a stopping period, is minimized. The stopping period is defined as the time interval between the explosion and the standstill of the cellular wheel. In particular, the stopping distance is dimensioned such that undesired risk propagation is reliably prevented depending on the rotational speed of the cellular wheel and the size of the cellular wheel chambers and the size of the inlet shaft and outlet shaft.The cellular wheel lock enables efficient stopping of the cellular wheel. The stopping unit mechanically interacts with the cellular wheel. In particular, the stopping unit interacts directly with the cellular wheel. Additional coupling elements are unnecessary. Risks of failure of the stopping unit are reduced.A rotary feeder according to claim 2 is of uncomplicated and robust design. In particular, the stopping unit is mechanically coupled to the cellular wheel, in particular to a cellular wheel shaft of the cellular wheel.A rotary feeder according to claim 3 is of uncomplicated design. A brake motor, in particular a transmission brake motor, can be retrofitted in a cell wheel lock in an uncomplicated manner. In particular, a rotary feeder equipped with a brake motor can be later made available to form a rotary feeder according to the invention. A low-voltage asynchronous motor is used in particular as the brake motor. The brake motor functions as an engine brake. The brake motor comprises in particular a mechanical brake. The mechanical brake is arranged in particular on the fan side of the brake motor. The mechanical brake comprises in particular a disc brake with clutch which is activated by means of springs when the brake motor is switched off. During operation of the cellular wheel lock, the brake is released, in particular by means of a magnetic coil, so that the brake motor can rotate un braked, i.e. freely. The braking torque exerted on the brake motor by the mechanical brake can be specifically defined by selecting the type and / or the number of springs used. The type of spring is defined in particular by its spring constant. It is possible in particular to specifically define the braking torque for star feeder locks of different sizes.In particular, the brake motor also serves as a rotary drive for the rotary feeder.A rotary feeder according to claim 4 is mechanically uncomplicated. A blocking means enables a direct blocking of the rotational movement of the cellular wheel. For this purpose, the blocking means interacts in particular with a corresponding blocking recess of the cellular wheel. In particular, a plurality of blocking recesses are formed on the cell wheel, in particular on the cell wheel shaft. The blocking recess is in particular a depression formed in the radial direction with respect to the longitudinal axis and / or a radial through-opening, in which the blocking means can engage in the radial direction. The blocking means is in particular a radially displaceable bolt or web.Additionally or alternatively, the at least one blocking recess can also be formed on a driver of the cellular wheel shaft. The driver is in particular disc-like and in particular connected in a rotationally fixed manner to the star wheel shaft, in particular formed integrally. The driver rotates with the cellular wheel shaft about the longitudinal axis, wherein the blocking recesses are designed as through holes of the disk and are arranged on the disk in the circumferential direction. In this case, the blocking means is designed as an axially displaceable bolt or web.Additionally or alternatively, the blocking means can also be arranged on one or both side covers and have an axially displaceable bolt or web. Upon actuation of the blocking means, the bolt or web is displaced into the interior space of the housing in order to block a rotational movement of the cellular wheel on the cellular wheel wings. In this embodiment, the blocking recess is formed as a cell wheel chamber delimited between two cell wheel vanes. The blocking means is arranged in particular eccentrically to the axis of rotation on the side cover.The blocking means enables in particular a form-fitting blocking of the rotational movement of the cellular wheel. It is also possible to arrange a plurality of the blocking means described above, which are of different design, on a cellular wheel sluice. The at least one blocking means enables a direct blocking of the cellular wheel and in particular a direct stopping of the cellular wheel. The stopping unit with such a blocking means is also referred to as a quick-action shooting device. The high-speed shooting device guarantees that the rotary feeder will stop immediately under the highest safety requirements.A cellular wheel sluice according to claim 5 enables in particular stopping of the cellular wheel with reduced delay. In particular, a braking means of the stopping unit can act independently of the rotational position on the cellular wheel and brake the rotational movement of the cellular wheel. The braking means enables a force-locking braking of the rotational movement of the cellular wheel. The braking means acts in particular mechanically. The braking means is designed in the form of brake shoes which can be pressed radially onto the star wheel, in particular onto the star wheel shaft. Additionally or alternatively, the braking means can act magnetically, in particular in the form of an eddy current brake. The eddy current brake can be combined in particular with a friction brake which engages in particular only at the end of the braking process, in particular when the rotational speed of the cellular wheel is already reduced and is in particular at most 5 min -1, in particular at most 3 min -1 and in particular 1 min -1.The brake means is in particular a separate brake and / or clamping device. The separate brake and / or clamping device can be arranged in particular on one of the side covers and interact with an extension of the cellular wheel shaft, which is led out of the housing through the respective side cover. The separate brake can in particular also be arranged as an additional brake on the drive shaft on the transmission of the cellular wheel drive.A seal can also serve as braking means, which is arranged in the housing of the rotary feeder. The seal bears axially and / or radially against a side plate of the cell wheel. In particular, two seals are provided, each of which abuts a side plate. Due to the large sealing diameter, a high braking effect is generated on the side disk of the cellular wheel. In particular, the braking force, in particular the braking torque, can be set variably by means of an adjustment of a seal cassette and / or by means of an adjustable pressing ring, in particular an axial pressing force of the seal against the side plate. It is ensured in particular that after the end of the drive rotational movement the cellular wheel comes to a standstill within a predefined stopping distance. The sealing cassette and / or the adjustable pressing ring are held in particular on the side cover and are in particular embodied as integrated thereon. The blocking means in the form of the seal is in particular passive. In this case, the stopping unit is activated by the rotary drive of the cellular wheel being ended.Additionally or alternatively, the seal can also be pressed against the side plate in the radial direction. This is achieved in particular by a conical adjusting element, in particular an annular element with a conical inner surface, which corresponds to a corresponding conical counter-surface of a counter-element.A cellular wheel sluice according to claim 6 can be retrofitted in an uncomplicated manner. The stopping unit can be mounted in particular subsequently on the rotary feeder, in particular on the housing. The accessibility of the stopping unit is improved. Because the cellular wheel, in particular the cellular wheel shaft, can be extended from the housing in an uncomplicated manner by an axial extension, the interaction with the stopping unit is possible in an uncomplicated manner.A cellular wheel sluice according to claim 7 is of compact and in particular mechanically robust design. The stopping unit is held on the housing and in particular fastened directly or indirectly on one of the side covers.A cellular wheel sluice according to claim 8 ensures a direct rotational drive of the cellular wheel. The cell wheel is actively rotationally driven. The rotary drive is a motor, in particular an electric motor. The kinematic coupling of the rotary drive to the cellular wheel takes place in particular by means of a transmission and / or by means of a rotary drive means such as, for example, by means of a drive chain or a drive belt.A cellular wheel sluice according to claim 9 facilitates the direct detection of a rotational movement of the cellular wheel.A protection system according to claim 10 can be used in particular in the area of bulk material conveyance. The protection system comprises a cellular wheel sluice according to the invention, a bulk material conveying line connected thereto, in particular a first bulk material conveying line connected to the inlet shaft, and a second bulk material conveying line connected to the outlet shaft. A sensor is arranged along at least one bulk material conveying line, which sensor serves for detecting an explosion which acts on the bulk material conveying line. The sensor is in particular an explosion detection sensor, which is in particular designed as a pressure detection sensor. The pressure detection sensor is used to detect a sudden increase in pressure, i.e., a increase in pressure in a short time interval, which is defined as an explosion.Alternatively, the explosion detection sensor may be formed by a combination of the pressure sensor and the temperature sensor.In the case of an explosion, a pressure wave propagates at the speed of sound, with a possible flame front propagating more slowly, in this respect the pressure detection is sufficient for reliable explosion detection. Pressure sensors are used in particular in containers, in particular in explosively pressure-relieved containers, in particular in filters and / or in silos. Pressure sensors are in particular supplemented by temperature sensors in pipelines, since glowing product particles can trigger further explosions.The pressure diaphragm of the pressure sensor is connected in particular flush with the surface of the delivery line and / or is arranged in the upper region of the container outside the filling region. Temperature sensors are arranged on a conveying line and / or above a bulk material cone of a bulk material container in such a way that their optics face the product.Depending on the ignition capability of the product, smoke gas sensors in a container can also be used as explosion detection sensors.Rupture disks and / or rupture wires can also serve as explosion detection sensors. In the event of an explosion, electrical lines are destroyed and detected as an electrical signal.The sensor is designed to generate an explosion signal in the event of an explosion. The sensor is signal connection to a control unit in order to transmit the explosion signal. The control unit is in signal communication with the stopping unit. The control unit is configured to generate a stop signal after receiving the explosion signal and to transmit it to the stop unit. The stopping unit is configured to stop the rotational movement of the cellular wheel after receiving the stopping signal. The stopping takes place in a variably definable stopping period, wherein the size of the stopping period depends essentially on the rotational speed of the cellular wheel, the number of cellular wheel chambers and / or on the size of the inlet shaft and / or the outlet shaft. Typical rotational speeds for such cellular wheel locks are between 5 min -1 and 100 min -1, in particular between 8 min -1 and 100 min -1 and in particular between 15 min -1 and 60 min -1.The stopping period is in particular at most 1 s, in particular at most 0.5 s, in particular at most 0.3 s, in particular at most 0.2 s, in particular at most 0.15 s, in particular at most 0.12 s and in particular at most 0.1 s.A protection system according to claim 11 ensures a reduction of the stopping period in which the control unit has a short reaction time. The reaction time of the control unit is understood to mean the time period required by the control unit until the stop signal has arrived at the stop unit after the explosion.A rotary encoder on the protection system according to claim 12 ensures monitoring of the rotary movement of the cellular wheel, in particular also at a point in time after the stop signal has been generated and / or the stop unit has been triggered. It is thereby possible in particular that the protection system can have a plurality of stopping units, wherein at least one additional stopping unit can be activated if a required stopping does not take place as a result of the activation of a first stopping unit. In particular, a stepped activation and thus a stepped stopping process takes place by means of the plurality of stopping units. The monitoring of the stopping process of the cellular wheel shaft is possible by means of the rotary encoder and the control unit.Both the features specified in the patent claims and the features specified in the following exemplary embodiment of the rotary feeder according to the invention are each suitable, alone or in combination with one another, for further developing the subject matter according to the invention. The respective combinations of features are not restrictive with respect to the developments of the subject matter of the invention, but essentially have only exemplary character.Further features, advantages and details of the invention are evident from the following description of exemplary embodiments with reference to the drawing. The following are shown: FIG. 1 shows a schematic illustration of a protection system with a rotary feeder according to the invention, FIG. 2 shows a perspective view of the rotary feeder according to FIG. 1, FIG. 3 is a top view of the rotary feeder according to FIG. 2, FIG. 4 is a side view of the rotary feeder according to FIG. 2, FIG. 5 shows a schematic longitudinal sectional illustration of a rotary feeder according to a second exemplary embodiment with a brake motor as stopping unit, FIG. 6 shows a representation corresponding to FIG. 5 of a rotary feeder according to a third exemplary embodiment with a blocking means for the rotary feeder vanes as a stopping unit, FIG. 7 shows a representation corresponding to FIG. 5 of a cellular wheel lock according to a fourth exemplary embodiment with a blocking means for the cellular wheel shaft as a stopping unit, FIG. 8 shows a representation corresponding to FIG. 5 of a star feeder according to a fifth exemplary embodiment with a braking means as stopping unit, which is arranged on the gear mechanism of the star feeder 18, FIG. 9 shows a representation corresponding to FIG. 5 of a rotary feeder according to a sixth exemplary embodiment with a braking means in the form of a seal in the housing as a stopping unit, FIG. 10 shows a representation corresponding to FIG. 6 of a rotary feeder according to a seventh exemplary embodiment with an additional stopping unit in the form of a braking means according to FIGS. 2 to 4.A protection system, which is shown purely schematically in FIG. 1 and is identified as a whole by 1, comprises a cellular wheel lock 2 which comprises a housing 3. The housing 3 has an interior 4 into which an inlet shaft 5 opens at an inlet opening 35 and from which an outlet shaft 6 opens at an outlet opening 36. A cellular wheel 7 is arranged in the interior 4 and is mounted rotatably drivable about a longitudinal axis 8. The cell wheel 7 comprises a cell wheel shaft 9 extending along the longitudinal axis 8 and a plurality of cell wheel blades 10 fastened thereto. Between two star wheel blades arranged in the circumferential direction of the star wheel shaft 9, a so-called star wheel chamber 11 is formed in each case.The rotary feeder 2 is designed as a discharge feeder. This means in particular that the inlet shaft 5 and the outlet shaft 6 are each oriented transversely, in particular perpendicularly, to the longitudinal axis 8.The rotary feeder 2 can also be designed as a blow-through feeder, in which the outlet shaft 6 is oriented in particular parallel to the longitudinal axis 8.On the cellular wheel shaft 9 there is arranged a rotary encoder 25 which is in signal connection with a control unit 15. The rotary encoder 25 is arranged in particular outside the housing 3.A first bulk material conveying line 12 is connected to the inlet shaft 5. Bulk material is fed to the rotary feeder 2 via the first bulk material conveying line 12.A second bulk material conveying line 13 is connected to the outlet shaft 6. Bulk material is discharged from the cellular wheel sluice 2 via the second bulk material conveying line 13.At least one sensor 14 is connected to each of the bulk material conveying lines 12, 13. It is also conceivable to provide a plurality of sensors 14 along the bulk material conveying lines 12, 13, respectively.The sensors 14 are in signal communication with the control unit 15. The control unit 15 is in signal communication with a stopping unit 16. The stopping unit 16 serves for the targeted stopping of a rotational movement of the cellular wheel 7 about the longitudinal axis 8. The stopping unit 16 is part of the rotary feeder gate 2.In the following, an exemplary embodiment of a rotary feeder according to the invention is explained in more detail with reference to FIGS. 2 to 4.Bulk material can flow through the cellular wheel sluice 2 from the inlet shaft 5 through the interior 4 to the outlet shaft 6 along a material flow direction 17. The interior 4 of the housing 3 is substantially cylindrical and is aligned in particular concentrically with respect to the longitudinal axis 8. The longitudinal axis 8 serves as an axis of symmetry for the interior space 4.The cellular wheel 7 can be driven in rotation by means of a cellular wheel drive 18. The cellular wheel drive 18 interacts with the cellular wheel shaft 9. For this purpose, a coupling pin, not shown, extending the star wheel shaft 9 engages in a corresponding receptacle of a drive connection, not shown in detail, of the star wheel drive 18. The cellular wheel drive 18 comprises a rotary drive 19 and a reduction gear 20 coupled thereto. In addition, a force transmission element, not shown in detail, can be present, in particular a chain drive, a belt drive and / or an intermediate shaft.The housing 3 is closed along the longitudinal axis 8 with side covers. A first side cover 21 is arranged facing the cellular wheel drive 18. A second side cover 22 is arranged on the opposite end face of the housing 3, which is oriented facing away from the cellular wheel drive 18. On the second side cover 22, a bearing 23 is arranged in which a shaft end of the cellular wheel shaft 9 is mounted rotatably but axially non-displaceably. The bearing 23 is supported by the second side cover 22. The side covers 21, 22 are detachably fastened to the housing 3 by means of fastening elements, in particular fastening screws, which are not shown in detail.The cellular wheel shaft 9 is guided through the bearing 23 and in particular sealed in the axial direction with respect to the longitudinal axis 8 by a cellular wheel shaft extension 24. The cellular wheel shaft extension 24 forms a free end of the cellular wheel shaft 9. According to the exemplary embodiment shown, the stopping unit 16 is designed as a braking means, in particular in the form of a clamping device or as a separate brake. The brake means is arranged on the second side cover 22. The braking means may cooperate directly with the cellular shaft extension 24. The accessibility of the cellular wheel shaft 9 or of the cellular wheel shaft extension 24 is uncomplicated. The stopping unit 16 is in signal communication with the control unit 15. In particular, the control unit 15 is in signal connection with the cellular wheel drive 18, in particular with the rotary drive 19.The braking means can also be arranged on the first side cover 21, in particular in the axial direction of the longitudinal axis 8 between the first side cover 21 and the cellular wheel drive 18.The function of the protection system 1 is explained in more detail below.An explosion which acts on one of the bulk material conveying lines 12, 13 is detected by at least one of the sensors 14. The respective sensor 14 generates an explosion signal and transmits it to the control unit 15. The control unit 15 generates a stop signal and transmits it to the stop unit 16. The stopping period is selected such that an unintentional spreading of the explosion from the one bulk material conveying line 12, 13 into the respective other bulk material conveying line 13, 12 through the cellular wheel lock 2 is reliably prevented. The protection system 1 with the rotary feeder 2 according to the invention meets high safety standards.A second embodiment will be described below with reference to FIG. 5. Structurally identical parts are given the same reference numerals as in the preceding exemplary embodiment, to the description of which reference is hereby made. Structurally different, but functionally similar, parts are given the same reference numerals with an suffix a.In the rotary feeder 2 a, the stopping unit 16 ais designed as a brake motor. The integration of the stopping unit 16 ais particularly uncomplicated if the rotary drive 19 is designed as a brake motor, i.e. has an additional, separate but integrated brake 26. Alternatively, the brake motor can also be present in addition to the rotary drive 19.A third embodiment will be described below with reference to FIG. 6. Structurally identical parts are given the same reference numerals as in the preceding exemplary embodiments, to the description of which reference is hereby made. Structurally different, but functionally similar, parts are given the same reference numerals with an suffix b.In the rotary feeder 2 b, the stopping unit 16 bhas a blocking means 27. The blocking means 27 is designed as an axially displaceable pin or web and is arranged on one of the side covers 21, 22. A plurality of blocking means 27 can also be present, which are arranged on the first side cover 21 and / or on the second side cover 22. It is in particular conceivable to arrange the blocking means 27 on both side covers 21, 22. The blocking means 27 is arranged radially offset with respect to the longitudinal axis 8 on one of the side covers 21, 22. Upon actuation of the blocking means 27, the web or pin is axially displaced, namely through the side cover 21, 22 into the interior 4 of the housing 3.A fourth embodiment will be described below with reference to FIG. 7. Structurally identical parts are given the same reference numerals as in the preceding exemplary embodiments, to the description of which reference is hereby made. Structurally different, but functionally similar, parts are given the same reference numerals with an suffix c.In the case of the rotary feeder 2 c, the stop unit 16 ccomprises a blocking means 28 which is arranged on one of the side covers 21, 22 and eccentrically with respect to the longitudinal axis 8. A plurality of blocking means 28 can also be present, which are arranged on the first side cover 21 and / or on the second side cover 22. The blocking means 28 is designed as an axially displaceable pin or web, wherein the displacement direction is directed away from the interior 4 of the housing 3. The blocking means 28 can engage in one of a plurality of blocking recesses 29 which are designed as depressions or through-bores on a driver 30 of the cellular wheel shaft 9. The driver 30 is in particular disc-like and is arranged on an extension of the cellular wheel shaft 9 outside the housing 3. The disk-like driver 30 is connected to the cellular wheel shaft 9 in a rotationally fixed manner with respect to a rotational movement about the longitudinal axis 8. In particular, the driver 30 is embodied in one piece with the cellular wheel shaft 9. In the circumferential direction about the longitudinal axis 8, a plurality of blocking recesses 29 are arranged on the driver 30. The blocking recesses 29 are in particular circular bores or elongated holes extending in the circumferential direction.In this exemplary embodiment, the rotary encoder 25 cmay be designed as an inductive proximity switch, which is arranged on the driver 30. The proximity switch 25 cis arranged axially spaced apart from the driver 30. In the radial direction with respect to the longitudinal axis 8, the proximity switch 25 cis arranged on the circumferential line on which the blocking recesses 29 are arranged. The proximity switch 25 cis used to detect the blocking recesses 29 during a rotational movement of the cellular wheel shaft 9, i.e. of the driver 30. the proximity switch 25 cis in particular in signal connection with the control unit 15, not shown in FIG. 7.Upon actuation of the blocking means 28, the latter is axially displaced and can engage in one of the blocking recesses 29 on the driver 30 and thus directly block the rotational movement of the cellular wheel shaft 9.For safety reasons, in particular for avoiding injury, the stopping unit 16c, in particular the blocking means 28 and the driver 30, is housed in a safety housing 31. According to the exemplary embodiment shown, the stop unit 16 cis arranged on the housing side which is arranged opposite the cellular wheel drive 18. The stopping unit 16 cmay also be arranged on the housing side on which the cellular wheel drive 18 is arranged.A fifth embodiment will be described below with reference to FIG. 8. Structurally identical parts are given the same reference numerals as in the preceding exemplary embodiments, to the description of which reference is hereby made. Structurally different, but functionally similar, parts are given the same reference numerals with an suffix d.The star feeder 2 dcomprises a separate brake 26 d, which is arranged on the gear 20 of the star feeder 18. For this purpose, the star wheel shaft 9 is guided axially through the transmission 20 by a star wheel shaft extension 24, so that the separate brake 26 dmay be placed directly on the transmission 20. The separate brake 26 dmay be retrofitted in an uncomplicated manner. In particular, it is not necessary for the cellular wheel shaft 9 to be led out of the housing 3 on both sides.A sixth embodiment will be described below with reference to FIG. 9. Structurally identical parts are given the same reference numerals as in the preceding exemplary embodiments, to the description of which reference is hereby made. Structurally different, but functionally similar, parts are given the same reference numerals with an suffix e.In the rotary feeder 2 e, the stopping unit 16 eis passive. The stopping unit 16 ehas at least one seal 32 which can be pressed by means of a seal cassette 33 in the axial direction with respect to the longitudinal axis 8 against a side plate 34 of the cellular wheel 7 e. It is also possible to use a plurality of, in particular two, seals 32 for each side plate 34.As a result of the axial pressing, the seal 32, which is in particular designed as an O-ring, is deformed and has in particular a spherical, non-round cross-sectional shape. The seal 32 seals in particular axially and / or radially with respect to the longitudinal axis 8. The seal 32 is in particular an axial seal.The axial seal 32 is pressed axially against the side plate 34, in particular by means of an axial pressing element 38.The sealing cassette 33 is fastened to the side cover 21, in particular to the inner side thereof, and is arranged so as to be axially displaceable. The sealing cassette 33 can be displaced axially relative to the side cover 21 and relative to the cell wheel 7 e, i.e. relative to the side disks 34, by means of the axial pressing element 38 shown purely schematically in FIG. 9. In particular, a plurality of axial pressing elements 38 are provided per sealing cassette 33. The axial pressing element 38 is in particular a set screw which is held in the side cover 21 and has a movement thread with which an axial displacement of the sealing cassette 33 is made possible. The axial pressing element 38 can also be designed as an axial actuator, which is designed in particular pneumatically, hydraulically and / or electrically.The sealing cassette 33 has a disk section 37 which is arranged between the side disk 34 and the side cover 21 in the axial direction of the longitudinal axis 8. The disk section 37 is designed as an annular disk, wherein the cellular wheel shaft 9 is passed through the central opening of the annular disk and is accommodated in the side cover 21.Formed integrally with the disc portion 37 is an annular collar 39 which extends in the axial direction of the longitudinal axis 8. The annular collar 39 has an inner radius which is greater than an outer radius of the side disk 34. The axial seal 32 is inserted into the shoulder 40. The contact pressure and the braking torque on the cellular wheel 7 ecaused by the axial seal 32 can be adjusted, in particular variably, in such a way that, when the active rotary drive is ended, the cellular wheel 7 eis stopped in the predefined stopping period.According to a variant not shown in the figures, it is possible to achieve an additional radial pressing of the sealing element 32 by virtue of the fact that the sealing cassette also allows a radial pressing at least partially. For this purpose, the sealing cassette can have a conical inner contour in the region of the annular collar, which inner contour outputs a radial contact pressure force on the sealing element with a corresponding conical counter contour of a radial contact pressure ring.The rotary feeder 2 eis designed as a discharge feeder.A seventh embodiment will be described below with reference to FIG. 10. Structurally identical parts are given the same reference numerals as in the preceding exemplary embodiments, to the description of which reference is hereby made. Structurally different, but functionally similar, parts are given the same reference numerals with an suffix f.The cellular wheel sluice 2 f, i.e. substantially the cellular wheel sluice 2 bin accordance with FIG. 6, and additionally has a stopping unit 16 in the form of a braking means which is designed in particular analogously to the braking means 16 in accordance with FIGS. 2 to 4.It is possible to carry out a plurality of stopping units on the rotary feeder 2 fand to combine them with one another. It is possible in particular to combine at least one stopping unit with a brake motor or a brake means according to FIGS. 2 to 5, 8 and 9, on the one hand, and at least one stopping unit with a blocking means according to FIG. 6 or 7, on the other hand. During operation, the stopping unit with brake motor or brake means can first be activated. This stopping unit operates essentially non-destructively and can be used repeatedly. If it is not reliably possible with this stopping unit to stop the rotational movement of the cellular wheel, the additional stopping unit can additionally be activated with a blocking means which ensures a direct blocking of the cellular wheel. This stopping unit with blocking means enables an increased safety, but is damaged or destroyed due to its mode of operation, so that an exchange will become necessary.By a combination of different stopping units, it is possible to set a stopping profile in a targeted manner for a cellular wheel lock.List of reference characters1 Protection system 2 Cellular wheel lock 3 Housing 4 Interior 5 Inlet shaft 6 Outlet shaft 7 Cellular wheel 8 Longitudinal axis 9 Cellular wheel shaft 10 Cellular wheel chamber 11 Cellular wheel wing 12 First bulk material conveying line 13 Second bulk material conveying line 14 Sensor 15 Control unit 16 Stopping unit 17 Material flow direction 18 Cellular wheel drive 19 Rotary drive 20 Reduction gearing 21 First side cover 22 Second side cover 23 Bearing 24 Cellular wheel shaft extension 25 Rotary encoder 26 Brake 27 Blocking means 28 Blocking means 29 Blocking recess 30 Driver 31 Securing housing 32 Axial seal 33 Sealing cassette 34 Side disks 35 Inlet opening 36 Outlet opening 37 Disk section 38 Axial pressing element 39 Annular collar 40 ShoulderReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Cited Non-Patent LiteratureDIN EN 15089:2009-07 "Explosion Decoupling Systems

[0002]

Claims

A cellular wheel sluice for bulk material comprising a. a housing (3) having an interior space (4) and having an inlet opening (35) and an outlet opening (36), b. side covers (21, 22) which delimit the interior space (4) at the end face, c. a cellular wheel (7) which is arranged in the interior space (4) such that it can be driven in rotation about a longitudinal axis (8) and is held on the side covers (21, 22), d. a stopping unit (16; 16a; 16b; 16c; 16d; 16e) for the targeted stopping of a rotational movement of the cellular wheel (7), wherein the stopping unit (16; 16a; 16b; 16c; 16d; 16e) interacts with the cellular wheel (7).Cellular wheel sluice according to claim 1, characterised in that the stopping unit (16) is coupled, in particular mechanically, to the cellular wheel (7), in particular to a cellular wheel shaft (9) of the cellular wheel (7).Cellular wheel sluice according to one of the preceding claims, characterized in that the stopping unit (16a) has a brake motor for braking the rotational movement of the cellular wheel (7).Cellular wheel sluice according to one of the preceding claims, characterized in that the stopping unit (16b; 16c) comprises a blocking means (27; 28) for blocking the rotational movement of the cellular wheel (7).Cellular wheel sluice according to one of the preceding claims, characterized in that the stopping unit (16; 16a; 16d; 16e) has a braking means for braking the rotational movement of the cellular wheel (7).Cellular wheel sluice according to one of the preceding claims, characterized in that the stopping unit (16; 16a; 16b; 16c; 16d) is arranged outside the housing (3).Cellular wheel sluice according to one of the preceding claims, characterized in that the stopping unit (16; 16a; 16b; 16c; 16d) is fastened to the housing (3), in particular to one of the side covers (21, 22).Cellular wheel sluice according to one of the preceding claims, characterized bya rotary drive (19) which is operatively connected to the cellular wheel (7) for the rotary drive of the cellular wheel (7).Cellular wheel sluice according to one of the preceding claims, characterized bya rotary encoder (25) for detecting the rotary movement of the cellular wheel (7), wherein the rotary encoder (25) is fastened in particular directly to the cellular wheel source (9) and / or is arranged outside the housing (3).A protection system, in particular for the transport of bulk material, comprising a. a cellular wheel lock (2; 2a; 2b; 2c; 2d; 2e; 2f) according to one of the preceding claims, b. a bulk material conveying line (12, 13) connected to the cellular wheel lock (2; 2a; 2b; 2c; 2d; 2e; 2f), c. a sensor (14) arranged along the bulk material conveying line (12, 13) for detecting an explosion acting on the bulk material conveying line (12, 13), d. a control unit (15) which is in signal connection with the sensor (14) for obtaining an explosion signal generated by the sensor (14), wherein the control unit (15) is in signal connection with the stopping unit (16; 16a; 16b; 16c; 16d; 16e) and configured to transmit a stop signal to the stop unit (16; 16a; 16b; 16c; 16d; 16e) after receiving the explosion signal, wherein the stop unit (16; 16a; 16b; 16c; 16d; 16e) is configured to stop a rotational movement of the cellular wheel (7) in a variably definable stop period after receiving the stop signal.Protection system according to claim 10, characterised in that the control unit (15) has a reaction time which is at most 0.1 s.Protection system according to claim 10 or 11, characterised in that the control unit (15) is in signal connection with the rotary encoder (25).

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