Valve closing device and valve actuating assembly

Abstract

For a valve closing device (8), including an output shaft (9) for connecting a valve (3) and an input shaft (10) for connecting an actuating drive (2), it is provided that an emergency drive (11) for driving the output shaft (9) in the event of a mains power failure is designed as a constant force spring motor (28) and/or a force flow from the emergency drive (11) to the output shaft (9) is merged with a force flow from the input shaft (10) to the output shaft (9) by an overriding gear arrangement (16) and/or the emergency drive (11) is locked and released by a locking device (19).

Claims

1. A valve closing device (8), comprising: a driven shaft (9), an input shaft (10) coupled to the driven shaft (9) by which the driven shaft (9) is drivable during operation, an emergency drive (11) that transfers the driven shaft (9) from a position of use into an end position, the emergency drive (11) comprises at least one constant force spring motor (28, 39, 40), the at least one constant force spring motor (28, 39, 40) comprises at least one band-shaped spring element (13) that is coiled in a spiral in a relaxed state, a further roller (14), the at least one band-shaped spring element (13) is wrapped on the further roller (14) for tensioning the at least one constant force spring motor (28, 39, 40), a superposition gear arrangement (16) by which the emergency drive (11) is coupled with the driven shaft and by which the input shaft (10) is coupled with the driven shaft (9), the superposition gear arrangement (16) comprises: a planetary gear that includes coaxially arranged first and second sun wheels (44, 45), the first sun wheel (44) is connected to the input shaft, the second sun wheel (45) is connected to the driven shaft, and a planetary gear block (43) that couples the sun gears (44, 45) together.

2. The valve closing device (8) as claimed in claim 1, wherein the at least one constant force spring motor (28, 39, 40) is tensionable by at least one of the input shaft (10) or a tensioning device (15).

3. The valve closing device (8) as claimed in claim 1, wherein the at least one constant force spring motor (28, 39, 40) comprises two or more of the band-shaped spring elements (13).

4. The valve closing device (8) as claimed in claim 3, wherein the constant force spring motor (28, 39, 40) is tensionable as a result of untensioning the at least one spring element (13), and in a tensioned state the at least one spring element (13) is tensioned in opposition to a tensioning direction of the constant force spring motor (28, 39, 40).

5. The valve closing device (8) as claimed in claim 1, wherein the emergency drive (11) comprises at least two of the constant force spring motors (28, 39, 40) connected in parallel or the at least one constant force spring motor (28, 39, 40) drives the driven shaft (9) by a multi-stage reduction gear.

6. The valve closing device (8) as claimed in claim 1, wherein the superposition gear arrangement (16) further comprises a planet gear carrier (17), and the emergency drive (11) drives the planet gear carrier (17).

7. The valve closing device (8) as claimed in claim 1, further comprising a regulating device (37) that regulates a tensioning device (15) of the emergency drive (15) such that a rotational movement of the input shaft (10) is compensated to stop a rotational movement of the driven shaft (9) when the emergency drive (15) is tensioned, and a sensor (36) connected to the regulating device (37) and that detects a rotational movement of the driven shaft (9).

8. The valve closing device (8) of claim 1, further comprising a locking device (19) set up for at least one of locking the emergency drive (11) in the event of mains operation or for releasing the emergency drive in the event of mains failure.

9. The valve closing device (8) as claimed in claim 8, wherein the locking device (19) is a self-locking gearing arrangement (20) which is drivable by the emergency drive (11) or the locking device (19) comprises a pawl (21) which is movable between a locking position and a releasing position, and in the locking position the pawl locks with a gearing part (22) which is drivable by the emergency drive (11).

10. The valve closing device (8) as claimed in claim 9, wherein the gearing part (22) is a planet gear carrier (17) of the superposition gear arrangement (16).

11. The valve closing device (8) as claimed in claim 9, wherein the pawl (21) is provided on a free end of a toggle lever (25).

12. The valve closing device (8) as claimed in claim 9, further comprising a motor-operated disengaging device (24) that is adapted to transfer the pawl (21) into the releasing position.

13. The valve closing device (8) as claimed in claim 12, wherein the disengaging device (24) comprises a lifting magnet.

14. A valve actuating assembly (1), having an actuating drive (2) for actuating, in the event of mains operation, a driven shaft (9) which is operatively connected to a valve (3) and having the valve closing device (8) according to claim 1 for actuating the driven shaft (9) in the event of mains failure.

15. The valve actuating assembly (1) as claimed in claim 14, wherein the valve closing device (8) is connected to the actuating drive (2) as a separate unit.

16. The valve actuating assembly (1) as claimed in claim 14, further comprising a valve (3) for producing an operative connection is connected to the driven shaft (9).

17. The valve closing device (8) as claimed in claim 1, wherein the at least one constant force spring motor (28, 39, 40) is tensionable by an electric motor driven tensioning device (15).

18. The valve closing device (8) as claimed in claim 1, wherein planetary gear block (43) comprises at least one planet gear (18).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is now described in more detail by way of exemplary embodiments, but is not limited to these exemplary embodiments. Further exemplary embodiments are produced as a result of the combination of the features of individual or several claims together and/or with individual or several features of the exemplary embodiments, in which:

(2) FIG. 1 shows a highly schematic block diagram representation of a valve actuating assembly according to the invention with a valve closing device and actuating drive according to the invention to explain the principle according to the invention,

(3) FIG. 2 shows the power train in the case of a mains failure in a valve actuating assembly according to FIG. 1,

(4) FIG. 3 shows a constant force spring motor of a valve actuating assembly according to FIG. 1,

(5) FIG. 4 shows a coiled, tensioned band-shaped spring element of the constant force spring motor according to FIG. 3,

(6) FIG. 5 shows the power train in a valve actuating assembly according to FIG. 1 in normal operation,

(7) FIG. 6 shows a three-dimensional inclined representation of a superposition gear arrangement of a valve actuating assembly according to FIG. 1,

(8) FIG. 7 shows a further superposition gear arrangement of a valve actuating assembly according to FIG. 1,

(9) FIG. 8 shows a locking device of a valve actuating assembly according to FIG. 1,

(10) FIG. 9 shows a partially sectioned representation of the locking device according to FIG. 8,

(11) FIG. 10 shows a further locking device of a valve actuating arrangement according to FIG. 1 with a toggle lever,

(12) FIG. 11 shows the locking device according to FIG. 10 in the disengaged or releasing position,

(13) FIG. 12 shows a partially sectioned representation of the locking device in the position according to FIG. 11,

(14) FIG. 13 shows a further valve actuating assembly according to the invention with an integrated valve closing device according to the invention,

(15) FIG. 14 shows a further embodiment according to the invention of an emergency drive with two band-shaped spring elements,

(16) FIG. 15 shows a further embodiment according to the invention of an emergency drive with three band-shaped spring elements,

(17) FIG. 16 shows a further embodiment according to the invention of a superposition gear arrangement,

(18) FIG. 17 shows an emergency drive of a further embodiment according to the invention with several constant force spring motors,

(19) FIG. 18 shows a superposition gear arrangement of a valve actuating assembly according to the invention, and

(20) FIG. 19 shows the principle of operation of the superposition gear arrangement according to FIG. 18.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(21) FIG. 1 shows a highly simplified block diagram of a valve actuating assembly according to the invention given the overall reference of 1.

(22) The valve actuating assembly 1 has an actuating drive 2 by which a connectable or connected valve 3 can be operated.

(23) The actuating drive 2, in this connection, comprises in a manner known per se a motor 4 by which an output 5 is drivable.

(24) The motor 4, in this connection, can be drivable in an electric, pneumatic, hydraulic or other manner.

(25) A brake 6 and a gearing arrangement 7 are also arranged in a known manner per se between the motor 4 and the output 5. The power train between the motor 4 and the output 5 can be interrupted by way of the brake 6. The brake 6 can be omitted, where applicable, when the gearing arrangement 7 is self-locking.

(26) A valve closing device 8 according to the invention, which is described in more detail below, is arranged between the actuating drive 2 and the valve 3.

(27) The valve closing device 8 comprises a driven shaft 9 to which the already mentioned valve 3 is connectable for producing an operative connection. FIG. 1 shows the connected valve 3 after producing the operative connection.

(28) The valve closing device 8 also has an input shaft 10,

(29) The already mentioned actuating drive 2 is couplable to the input shaft 10.

(30) FIG. 1 shows the actuating drive 2 coupled to the valve closing device 8. The coupling is releasable in the case of the exemplary embodiment according to FIG. 1, and the valve closing device 8 is realized as a separate unit.

(31) The input shaft 10 is coupled with the driven shaft 9 such that the driven shaft 9 is drivable by way of the actuating drive 2 in normal operation in order to actuate the valve 3 or another connected valve.

(32) The valve closing device 8 further comprises an emergency drive 11. In the event of mains failure, that is if the actuating drive 2 is inoperative, the driven shaft 9 is drivable by way of the emergency drive 11 which is driven by way of the electric motor or mechanically, pneumatically or hydraulically at least until the driven shaft 9 is transferred into a defined end position.

(33) This end position can be defined such that a connected valve assumes a defined end state, for example a completely closed state or a completely open state.

(34) FIG. 2 shows the power train in the event of a mains failure.

(35) The symbol x indicates that the power train between the motor 4 and the input shaft 10 is blocked. This can be achieved, for example, as a result of the brake 6 automatically coming in the event of a mains failure.

(36) In this case, it is provided that the emergency drive 11 drives the driven shaft 9 in the described manner.

(37) In the case of the exemplary embodiment shown, the emergency drive 11 is realized for mechanical operation as a constant force spring motor.

(38) Such a constant force spring motor 28 as an emergency drive 11 is shown in FIG. 3.

(39) The emergency drive 11 has a first roller 12 onto which a band-shaped spring element 13 is coiled.

(40) FIG. 3 shows the emergency drive 11 in the tensioned state.

(41) FIG. 4 shows the spring element 13 of the emergency drive 11 from FIG. 3.

(42) It is apparent that the spring element 13 is coiled in a spiral manner on the first roller 12.

(43) The emergency drive 11 has a second roller 14 which does not have anything wrapped around it in the tensioned state according to FIG. 3.

(44) To tension the emergency drive 11, the band-shaped spring element 13 is consequently coiled onto the first roller 12.

(45) In this connection, the spring element 13 is unrolled by the second roller 14. The spring element 13 is consequently coiled onto the first roller 12 from the second roller 14.

(46) During the coiling process, the first roller 12 and the second roller 14 are moved in opposite directions.

(47) The achievement as a result is that in the tensioned state of the emergency drive 11, that is when the spring element 13 is completely tensioned onto the first roller 12, the spring element 13 is coiled in opposition to a preferred direction of rotation.

(48) If the emergency drive 11 is then left to its own devices, the tension in the spring element 13 is released by it being coiled onto the second roller 14.

(49) As a result of the resultant movement of the first roller 12 or of the second roller 14, the driven shaft 9 is driven until the desired end position is reached.

(50) In the case of the valve closing devices 1 shown according to the invention, a constant force spring motor 28 according to FIG. 14 or a constant force spring motor 28 according to FIG. 15 can be used instead of the constant force spring motor 28 according to FIGS. 3 and 4.

(51) The statement relating to FIGS. 3 and 4 apply correspondingly to FIGS. 14 and 15.

(52) The constant force spring motor 28 of the emergency drive 11 according to FIG. 14 differs from the constant force spring motor 28 according to FIG. 3 in that there are two band-shaped spring elements 13 present which, offset with respect to one another in the circumferential direction, cooperate with the roller 12 which carries the spring elements 13 in the tensioned state.

(53) A tensioning arrangement in which the spring elements 13 form a double-flight winding is produced as a result, i.e. a winding in which the spring elements 13 form layers which follow one after another alternately in the radial direction.

(54) When the energy is released, each of the spring elements 13 is tensioned around a separate roller 14.

(55) The drive shaft 38 (cf. FIG. 1) of the emergency drive 11, by means of which the emergency drive 11 acts on the superposition gear arrangement 16, is connected to the roller 12. Consequently, said drive shaft 38 is tensioned by the spring elements 13 when the energy is released, which is advantageous for the power transfer.

(56) FIG. 15 shows an emergency drive 11 with a constant force spring motor 28 with three band-shaped spring elements 13. In this way, a triple-flight winding is produced in the tensioned state. Apart from this, the statements relating to FIG. 14 are applicable.

(57) In the case of further exemplary embodiments, more than three spring elements 13 cooperate with one common roller 12 in order to form a multi-layered winding in the tensioned state. It can also be provided that said single, double or multi-layered winding defines the energy-releasing state. Here too, it is favorable when the drive shaft 38 is/are coupled with the roller or the rollers 12, 14 which is/are tensioned by the spring element or spring elements when the energy is released.

(58) Another tensioning device 15 can be seen in FIG. 1 and the emergency drive 11 can be tensioned by way of said tensioning device. The tensioning device 15, in this connection, can be driven by electric motor or in a pneumatic or hydraulic or other manner, for example even manually.

(59) Tensioning the emergency drive 11 can also be executable from the operation of the actuating drive 2 without a separate tensioning device 15.

(60) Frequently the size of the reducing gear ratio of the gearing arrangement 20 (no self-locking in this case) is chosen such that it is not possible to tension the emergency drive 11 by way of the motor 4. A tensioning device 15 is present in this case.

(61) In the case of a further exemplary embodiment, tensioning the emergency drive 11 can be made possible and carried out in a combination, that is an interaction, between the actuating drive 2 and the device 15.

(62) The valve closing device 1 comprises a sensor 36 for this purpose. The sensor 36 can comprise a positioning sensor, speed sensor, torque sensor or in any other manner in order to detect a rotational movement of the driven shaft 9 and/or to differentiate between a standstill of the driven shaft 9.

(63) A regulating device 37 is set up in this connection such that a rotational movement of the input shaft 10 is compensated for by the actuating drive 2 by a movement of the planet gear carrier 17 precisely in such a manner that a desired rotational movement of the driven shaft 9, for example a standstill, is achieved. Consequently, the achievement can be, for example, that the connected valve 3 is not moved during the tensioning of the emergency drive 11. For example, a valve of the valve 2 can be held in the open position or in the closed position in this way.

(64) It can be seen in FIG. 1 that the power train from the emergency drive 11 and from the motor 4 are joined together in a superposition gear arrangement 16 and are forwarded together to the driven shaft 9.

(65) FIG. 6 and FIG. 7 show two examples of a usable superposition gear arrangement 16 which are realized in each case as differential gearing arrangements.

(66) From the representations according to FIG. 6 and FIG. 7, it can be seen that the driven shaft 9 and the input shaft 10 describe the main power train through the superposition gear arrangement 16. In the case of further exemplary embodiments, further gearing arrangements can be interposed between the superposition gear arrangement 16 and the driven shaft 9 or the input shaft 10.

(67) It can be seen in any case that the gear ratio between the driven shaft 9 and the input shaft 10 is one to one.

(68) Planet gears 18 which produce the coupling between the input shaft 10 and the driven shaft 9 are arranged in each case on a planet gear carrier 17.

(69) If the planet gear carrier 17 is blocked, the direct gearing ratio is produced between the driven shaft 9 and the input shaft 10. In this connection, the direction of rotation of the movement is reversed.

(70) The emergency drive 11 cooperates with the planet gear carrier 17 by means of the geared wheel 34 and moves said planet gear carrier.

(71) In this way, the torque introduced at the input point 29 by means of the input shaft 10 can be added to the torque introduced at the input point 29 by the emergency drive 11 by means of planet gear carrier 17.

(72) The exemplary embodiment according to FIG. 6 shows a bevel differential gearing arrangement, while the exemplary embodiment according to FIG. 7 shows a spur differential gearing arrangement. Further types of differential gearing arrangements, for example planetary gearing arrangements, can be used in an advantageous manner.

(73) FIG. 18 shows a further superposition gear arrangement 16, as can be used and/or is used in the case of the valve closing devices 8 according to the invention of the shown and/or described valve actuating assemblies 1.

(74) The superposition gear arrangement 16 is provided in this case as an epicyclic gearing arrangement and has an planet gear carrier 17, in this case a planet carrier which carries planet gears 18. The planet gears 18 form in each case a planet gear block 43.

(75) The superposition gear arrangement 16 has a first sun wheel 44 and a second sun wheel 45 which are aligned coaxially with respect to one another.

(76) The first sun wheel 44 is non-rotatably connected to the input shaft 46 of the superposition gear arrangement 16. The second sun wheel 45 is non-rotatably connected to the output shaft 47 of the superposition gear arrangement 16.

(77) The input shaft 46 of the superposition gear arrangement 16 merges into the input shaft 10 of the valve closing device 8 or is rigidly coupled with said valve closing device.

(78) The output shaft 47 of the superposition gear arrangement 16 merges into the output shaft 9 of the valve closing device 8 or is rigidly coupled with said valve closing device.

(79) The sun wheels 44, 45 mesh in each case with the planet gears 18 of the planet gear blocks 43. As a result, there is a power train between the input shaft 46 and the output shaft 47.

(80) The number of teeth on the sun wheels 44, 45 differs slightly from one another such that there is a gear ratio of almost one, but not precisely one, between the input shaft 46 and the output shaft 47 when the planet gear carrier 17 is held.

(81) In this connection, flank forms, in particular the profile shifts, of the sun wheels 44, 45 are chosen so as to be different such that the points of engagement with the planet gears 18 are the same for both sun wheels 44, 45. The planet gears 18 are in each case integral and consequently comprise in each case a uniform number of teeth.

(82) Consequently, a four-wheel planetary gearing arrangement is formed in the described manner as an epicyclic gearing arrangement.

(83) FIG. 19 shows a simplified representation of a basic design of the superposition gear arrangement 16 according to FIG. 18 for explaining a power train and the principle of operation as a four-wheel planetary gearing arrangement. The further toothing parts in FIG. 18 are provided for reinforcement and are unnecessary for the principle of operation. It is obvious that the planetary gear block 43 can be provided in a divided manner such that the sun wheels 44, 45 with the two planetary gears, the planet gears 18 of the planetary gear block 43 form a basic design of a four-wheel planetary gearing arrangement. Apart from this, the statements for explaining FIG. 18 are applicable to FIG. 19 in a corresponding manner.

(84) In the case of further exemplary embodiments, each planetary gear block 43 comprises two separate planetary gears which are coupled non-rotatably on a common shaft and in each case only mesh with one of the two sun wheels 44, 45, as is shown as an example in FIG. 19.

(85) In the case of said type of superposition gear arrangement 16 according to FIG. 18, the number of planetary gear blocks 43 used frequently matches the difference in the number of teeth of the sun wheels 44, 45.

(86) In the exemplary embodiment according to FIG. 18, the difference in the number of teeth is 2 and there are precisely two planetary gear blocks 43.

(87) The emergency drive 11 is coupled to the planet gear carrier 17 by the toothed wheel 34. As a result, there is a reduction gear ratio between the toothed wheel 34 and the output shaft 47 of 10 or more than 10. In the exemplary embodiment, the gear ratio between the input shaft 46 and the output shaft 47 with the toothed wheel 34 held is precisely at 1.1, and the gear ratio between the toothed wheel 34 and the output shaft 47 with the input shaft 46 held is precisely at 10. In the case of a further exemplary embodiment, the gear ratio between the input shaft 46 and the output shaft 47 with the toothed wheel 34 held is precisely at 1.066 and the gear ratio between the toothed wheel 34 and the output shaft 47 with the input shaft 46 held is precisely at 15. Other numeral values are also realizable as a result of choosing the number of teeth.

(88) The superposition gear arrangement 16 consequently overrides the rotational movements on the input shaft 46 and on the toothed wheel 34 to form a rotational movement on the output shaft 47. The torques are added up in this connection.

(89) It is obvious thatin contrast to the otherwise similar arrangement according to FIG. 7the rotational movement between the input shaft 46 and the output shaft 47 is not reversed, but is transmitted in the same direction.

(90) Apart from this, the explanations relating to FIGS. 6 and 7 are applicable in a corresponding manner to the exemplary embodiment according to FIG. 18 and FIG. 19.

(91) In the case of a further exemplary embodiment according to FIG. 16, the emergency drive 11 does not engage via a toothed wheel, but by means of a drive element 35, here shown as an example as a connecting rod or crank or lever mechanism. By a gear ratio of 1:1 being realized between the input shaft 10 and the driven shaft 9, there is a gear ratio of 1:2 between the input point 29 of the emergency drive 11 and the driven shaft 9 with the input shaft 10 locked. Consequently, the planet gear carrier 17 rotating about 90? by means of the drive element 35, for example, with the input shaft 10 held, causes the driven shaft 9 to rotate about 180?. This travel is already sufficient for many applications.

(92) Apart from this, the statements relating to FIGS. 1 to 6 are applicable to FIG. 16.

(93) It can also be seen in FIG. 1 that the valve closing device 8 comprises a locking device 19.

(94) The emergency drive 11 is lockable during mains operation and releasable in the event of mains failure using the locking device 19.

(95) For this purpose, the locking device 19 comprises a self-locking gearing arrangement 20 which blocks a power train from the superposition gear arrangement 16 to the emergency drive 11, in one sense of direction.

(96) The emergency drive 11, in this case, is not tensioned by the motor 4, but by means of the separate tensioning device 15.

(97) If no self-locking gearing arrangement 20 is present, the emergency drive 11 can be tensioned by means of the superposition gear arrangement 16for example with the driven shaft 9 held.

(98) As an alternative to or in addition to the self-locking gearing arrangement 20, the locking device 19 comprises a pawl 21 which interacts in a blocking manner with a gearing part 22 in the locking position.

(99) To this end, the pawl 21 engages in a corresponding recess 23 on the gearing part 22. The pawl 21 consequently locks in both senses of direction to the emergency drive 11 and from the emergency drive 11.

(100) When the locking device 19 is released, the gearing part 22 is drivable by way of the emergency drive 11. The pawl 21 consequently blocks the emergency drive 11 in the engaged position.

(101) FIG. 1 indicates that the pawl can cooperate with the emergency drive 11, the self-locking gearing arrangement 20 or the superposition gear arrangement 16 in order to bring about the locking process. In the case of further exemplary embodiments, gearing parts 22 of other devices of the valve closing device 8 can also be locked by way of a pawl 21. For example, the gearing part 22 can be realized on the planet gear carrier 17.

(102) FIG. 5 shows the power train with the emergency drive 11 locked.

(103) The power train in normal operation from the motor 4 to the drive shaft 9 is consequently shown. Once again the symbol x marks a power train interrupted by locking.

(104) The locking device 19 has a disengaging device 24, by way of which the pawl 21 can be disengaged out of the recess 23 of the gearing part 22.

(105) FIG. 8 and FIG. 9 show an exemplary embodiment where the pawl 21 can be disengaged and engaged as a result of direct linear displacement.

(106) The disengaging device 24 is realized here as an electrically actuatable lifting magnet. The lifting magnet can comprise a return spring which is not shown in any detail and is known per se.

(107) FIGS. 10 to 12 show an alternative locking device 19 for use in the valve actuating assembly 1 according to FIG. 1.

(108) It is apparent that the pawl 21 is realized on the free end of a toggle lever 25.

(109) FIG. 10 shows the extended toggle lever 25, while FIG. 11 shows the angled state of the toggle lever 25. The angled state of the toggle lever 25 consequently defines the releasing position of the locking device 19.

(110) From the partially sectioned representation according to FIG. 12, it can be seen that the toggle lever 25 comprises a joint 26, the disengaging device 24here a lifting magnet alsoengaging in said joint. The toggle lever 25 is consequently formed by two legs 30, 31 which are connected by the joint 26. A free end which forms the pawl 21 is realized on the end of the one leg 30 remote from the joint 26. The toggle lever 25 is pivotably mounted on the end 33 of the other leg 31 remote from the joint 26.

(111) The disengaging device 24 consequently engages in a transverse manner with reference to the direction of movement of the extended toggle lever 25 (cf. FIG. 10). The extended toggle lever 25 defines the locked position of the locking device.

(112) The achievement as a result of using a toggle lever 25 can be that at the start of the disengaging movement a large force can be introduced onto the pawl 21 as the power transmission ratio of the disengaging device 24 to the pawl 21 with the toggle lever 25 extended is very favorable.

(113) Consequently, it is possible to overcome large holding forces at the pawl 21 which are brought about as a result of clamping the gearing part 22.

(114) FIG. 13 shows a further valve actuating assembly 1 according to the invention.

(115) Components and functional units that are the same or similar functionally and/or structurally to the previously described exemplary embodiments are designated with the same references and are not described again separately. The statements relating to FIGS. 1 to 12 are consequently applicable in a corresponding manner to FIG. 13.

(116) The valve actuating assembly 1 according to FIG. 13 differs from the valve actuating assembly 1 according to FIG. 1 in that the valve closing device 8 according to the invention is integrated into the actuating drive 2, that is into the housing 27 thereof.

(117) The advantage of this, for example, is that the gearing 7 and the output 5 are able to be omitted in relation to FIG. 1.

(118) In the case of the exemplary embodiment according to FIG. 13, the indicated valve 3 is also releasably connectable to the driven shaft 9 for producing an operative connection or driving connection.

(119) FIG. 17 shows a further emergency drive 11 of a valve closing device according to the invention, details which are not necessary for explaining the invention having been omitted.

(120) The emergency drive 11 has a drive shaft 38 which can also be seen in the previously described Figures. This drive shaft 38 is non-rotatably coupled with a toothing part 42.

(121) Three constant force spring motors 28, 39, 40 are uniformly distributed along the circumference of the toothing part 42 and cooperate with said toothing part.

(122) In the case of further exemplary embodiments, a different number of constant force spring motors cooperate therewith.

(123) The constant force spring motors 28, 39, 40 drive the common toothing part 42 together such that the individual torques of the constant force spring motors 28, 39, 40 are added up.

(124) The constant force spring motors 28, 39, 40 are consequently connected in parallel together. Each of the constant force spring motors 28, 39 and 40 apply in each case a third of the overall required torque.

(125) Each constant force spring motor 28, 39, 40 is drivingly connected to the toothing part 42 by means of a gearing arrangement 41, here a multi-stage reducing gear for speed reduction.

(126) Apart from this, the function of each of the constant force spring motors 28, 39, 40 taken in isolation is as described previously. The statements consequently apply in a corresponding manner to FIG. 17, the same references having been retained.

(127) In the case of a valve closing device 8 with a driven shaft 9 for connection to a valve 3 and an input shaft 10 for connection to an actuating drive 2, it is proposed, for driving the driven shaft 9 in the event of mains failure, to realize an emergency drive 11 as a constant force spring motor 28 and/or to join a power train from the emergency drive 11 to the driven shaft 9 with a power train from the input shaft 10 to the driven shaft 9 by means of a superposition gear arrangement 16 and/or to lock and to release the emergency drive 11 by way of a locking device 19.