DE102006049389A1 - Door motor for use in vehicle heating apparatus has regulation coupling for regulating the motor output shaft opposite the door movement element as well as a pressure element for pressurising the motor - Google Patents

Abstract

The door motor has a motor unit (2) with a drive motor (3) and a motor output shaft (4) as well as an output gear (8) that is connectable with the motor output shaft on the input side, whilst there is a gear output shaft (18) to drive the door movement element, especially a door shaft. There is a regulation coupling for regulating the motor output shaft opposite the door movement element as well as a pressure element (30, 31, 40) for pressurising the motor.

Description

The The present invention relates to a door operator for a garage, Garden, hall or industrial door, with a motor unit, the a drive motor and an engine output shaft, an output drive, the input side is connectable to the engine output shaft and on the output side, a transmission output shaft for driving a door movement element, in particular a door shaft, having, a Entriegelungskupplung for unlocking the engine output shaft relative to the Torbewegungselement and a damping element for damping of drive shocks.

To the Drive from gates such as garage doors, garden gates, hall gates or also great Industrial doors are regularly electric motors used that over an output gear a Torbewegungselement, usually a Torwelle, drive, for example, to wind up a goal rope or a torkette, where the gate is attached. It is understood that other door elements can be used. More specifically, there are actually two gears between the actual drive motor and the Torbewegungselement provided. First that gets very regular high speed of the electric motor, for example via a worm gear stage reduced to the speed of the engine output shaft. This first gear is but as it were part of the engine unit and often part of the purchased Electric motor or the motor unit. To the speed of the engine output shaft to adapt to the requirements of the door drive is also a Another gear used on the engine output shaft sits and with the transmission output shaft, the door movement element drives.

For this Output gear is usually on the motor unit a transmission housing provided in which the transmission elements, usually a spur gear, are arranged and mounted on the also the transmission output shaft becomes.

in this connection However, it comes because of the dimensional tolerances many items often cause inaccuracies in the transmission. A damping and an unlocking will be additional attached in different places, so that overall long tolerance chains arise. In addition, the motor unit must be specially designed for the respective application be adjusted.

Of the The present invention is based on the object, to provide an improved door drive of the type mentioned, the disadvantages of the prior art avoids and the latter in an advantageous manner Way further education. In particular, should a simple means Adjustment of the drive motor to the driven gate allows and long tolerance chains are avoided here in the output gear.

According to the invention this Problem solved by a door drive according to claim 1. preferred Embodiments of the invention are the subject of the dependent claims.

It So it is proposed that the output gear is no longer in the motor unit or the housing to integrate the motor unit. Rather, according to the invention, the output drive has a transmission housing formed separately from the motor unit and together with the unlocking coupling and the damping element in a modular manner an independent one Drive attachment forms, on the one hand to the motor unit and their Motor output shaft and on the other hand connected to the Torbewegungselement. For the Door drive is thus proposed a modular design. With The separate drive attachment is, so to speak, the gap in the drive train closed between the drive motor and the Torbewegungselement. On the drive attachment, on the one hand, suitable for the respective goal Motor unit are attached or attached, including the drive attachment has adapted to the respective motor unit connection means. On the other hand, the drive attachment to the respective Torbewegungselement customizable connection means on to the respective Torbewegungselement to be connected. By Training the output gear as a separate drive attachment is avoided a long tolerance chain. In addition, through integration the Entriegelungskupplung and the damping element in these Drive attachment so to speak a complete package can be provided the necessary requirements for a door drive, such as unlocking and damping of drive shocks, regardless of the Implementation of the motor unit realized.

In Development of the invention can in the separate drive attachment further functional components of Be integrated gate drive. In particular, in the development of Invention a Wegerfassungseinrichtung, preferably a pulse disc, the Detecting the door position integrated into the drive attachment, in particular inside the gearbox added. The path detection device is advantageously arranged on the output side of the Entriegelungskupplung, wherein at training the path detection device with a pulse disc latter directly can sit on the transmission output shaft. The associated pulse reader is advantageously also arranged in the interior of the transmission housing.

Alternatively or additionally, an unlocking detection device for detecting the unlocking position of the unlocking coupling be integrated into the separate drive attachment, so that the function of Entriegelungsüberwachung is realized by the drive attachment. The Entriegelungserfassungs device may have a limit switch, which detects the unlocked position of the Entriegelungskupplung and beyond can cause a shutdown of the power supply of the motor unit when the release of the Entriegelungskupplung is detected. The limit switch can be attached to the transmission housing and monitor an operation of an unlocking lever, which actuates the Entriegelungskupplung and also may be mounted on the transmission housing.

Around to be able to connect the respectively suitable drive motor in a suitable orientation, are in Development of the invention on the drive attachment motor connection side provided different and / or variable connection means for the motor unit, so that different motor units and / or the same motor unit in different orientations relative to the drive attachment this can be attached. For example, you can the connection means comprise a plurality of sets of holes through which screwed the drive attachment to the respective motor unit can be. In particular, the connection means are provided on the transmission housing, to screw it to the motor unit.

alternative or additionally can the drive attachment also the output side different and / or variable connection means for connecting various door movement elements and / or the same Torbewegungselements in different orientations exhibit.

In particularly advantageous manner the motor-side connection means of the drive attachment a quick locking device include, by means of which the drive attachment to the motor unit quickly locked can be. The quick locking device can after an execution of the Invention tool-free actuated be educated. In particular, between the engine unit and the drive cap a bayonet closure be provided by means of which the drive attachment attached particularly quickly to the motor unit can be. The quick locking device is characterized here characterized in that motor-side engaging means and adapted thereto, provided on the drive attachment a handle means by combination an axial movement and a rotational movement in positive locking engagement can be brought. According to an advantageous embodiment of the invention can order the engine output shaft or a rotation axis parallel thereto rotatable mounted engagement claws to be provided with the complementary thereto Engagement recesses are engageable.

The gearbox can be fundamentally different be educated. According to a preferred embodiment of the invention it consists of two half-shells, which are divisible and of which one of the connection means for connecting the motor unit and the other storage means for support of the gearbox across from the driving forces or -momentes.

advantageously, can in the transmission housing the drive attachment various gear stages are used, different translation and / or reduction ratios between the engine output shaft and the transmission output shaft realize. By such a replaceable gear stage can the speed provided by the engine output shaft to the requirements be adapted to the respective gate, without each time a completely different one Drive attachment would have to be kept ready.

Especially the replaceable gear stage can have a pair of spur gears, a smaller and a larger spur gear includes. For this purpose, the gear ratio provided by the gear stage or reduction ratio simply changed be that the two spur gears together be reversed, which is possible with the same distance. Alternatively or in addition can Other spur gear pairs are used in the gearbox to completely different or further variations of the translation or Reduction ratio to reach.

The Gear stage can basically in the gearbox in various ways and be stored. According to an advantageous embodiment of Invention are all gears the gear stage supported on the same gear housing shell. hereby can be a precise one Storage can be achieved, which differs from connection tolerances housing parts is not affected.

The damping element for intercepting drive shocks can be integrated in various ways in the drive attachment. According to a preferred embodiment of the invention, the damping element is arranged on a damping element carrier which is detachably connected to the transmission housing, preferably externally attached to the transmission housing. The damping element carrier may preferably consist of a damping plate which is releasably secured to the front of the transmission output shaft in the region of the outlet of the transmission housing, in particular screwed, and has a radially spaced from the transmission output shaft damping element receptacle. The damping element can, for example, on a Door frame or another supported against the Torbewegungselement component be hinged, so that induced by the driving forces and moments driving shocks can be intercepted. Advantageously, while the damping plate is screwed at several points around the outlet of the transmission output shaft around the gear housing, so that the drive shocks are centrally intercepted. In this case, the damping element carrier and / or the transmission housing preferably has a plurality of and / or variable connection means in order to enable a connection of the damping element carrier to the transmission housing in different positions. The damping element carrier can be screwed in particular in different positions on the gear housing, for example, in each case rotated by a predetermined angular offset to allow the attachment in most favorable manner.

alternative or additionally to such a damping element can also be a damping element be provided between the drive attachment and the motor unit, wherein this damping element advantageously damping means which regards the motor output shaft radially effective and / or in the circumferential direction around the engine output shaft are effective. According to an advantageous embodiment of Invention may be the damping element an annular damping plate form, between the motor unit and the attached drive attachment sits and with both said components in preferably positive engagement sitting. The annular damping plate can axial and / or radial engagement projections and / or -ausnehmungen possess, by means of which they in positive engagement with the motor unit and the drive attachment or in each case with it connected interconnected components is.

Especially can the damping element so be formed and / or arranged that it by the aforementioned Quick locking device between the drive attachment and the motor unit can be fastened. The damping element is, so to speak integrated into the quick locking device.

Around to achieve a small structure arrangement is the Entriegelungskupplung at least with their locking or unlocking elements inside of the gearbox arranged. In particular, the Entriegelungskupplung between the Transmission output shaft and one of the gears of the gear stage arranged be, which sits on said transmission output shaft or connected with it. The unlocking coupling can be a at least partially slidably received in the transmission output shaft actuating pin have, which is actuated by an arranged on the gear housing outside actuator. The named actuating pin can operate a feather key, which mounted axially displaceable on the transmission output shaft is and depending on the axial position that on the transmission output shaft seated gear with this locked or opposite this releases.

In Further development of the invention is provided in the drive attachment Gear stage not the only gear stage of the entire door drive. In particular, the motor unit itself can also be the usual gear stage to reduce the speed of the electric motor to the speed of the Have motor output shaft. For example, between the electric motor shaft and the engine output shaft, a worm gear stage or else a bevel helical gear stage be interposed, however integral part of the motor unit and is housed inside the motor housing is.

The Invention will be described below with reference to preferred embodiments and associated drawings explained in more detail. In show the drawings:

1 : An exploded perspective view of a door drive with a gear attachment according to a preferred embodiment of the invention, and

2 : An exploded perspective view of a door drive with a gear attachment according to a further preferred embodiment of the invention.

The in 1 shown door drive 1 includes a motor unit 2 with an electric motor 3 and a motor output shaft 4 , In the illustrated embodiment, transverse to the longitudinal axis of the electric motor 3 extends. As electric motor 3 Different types of motors can be used. The engine output shaft 4 is advantageously via a transmission 5 with the motor shaft of the electric motor 3 coupled to the usually quite high speed of the electric motor 3 in a relatively lower speed of the engine output shaft 4 implement. The gear 5 is in the case 6 the motor unit 2 housed and can basically be designed differently. In particular, a worm gear or bevel gear can be provided to realize the speed reduction in the desired manner. The named transmission 5 is part of the motor unit 2 ,

On the engine output shaft 4 the motor unit 2 can be a drive attachment 7 be put on, the output gear 8th and further door drive functional components. About this gear tower can again a erforderli Che adjustment of the speed of the engine output shaft 4 be realized to the desired speed, for example, a door shaft, for example, the motor unit 2 to use for different goals. The drive attachment 7 forms an independent function block, which, as it were, between the motor unit 2 and the door moving element to be moved wel Ches is not specifically shown in the drawing, can be switched and the part of the drive train between the motor unit 2 and Torbewegungselement forms. Through this a completed functional unit forming drive attachment 7 receives the gate operator 1 a modular design that allows the door operator 1 assemble modularly and adapt to the requirements of the particular application. The drive attachment 7 in this case comprises an engine-side interface in order to be able to be connected to different motor units, and on the other hand an output-side interface for connecting the drive attachment 7 with the respective door movement element. The said interfaces include suitable connection means 9 and 10 to the drive attachment 7 torque transmitting to the motor unit 2 or to connect the Torbewegungselement. In the illustrated embodiment is the motor side as a connection means 9 a screw provided by means of which the housing 11 of the drive attachment 7 on the housing 6 the motor unit 2 can be releasably attached.

As 1 shows, includes the drive attachment 7 an output gearbox 8th , which in the illustrated embodiment as a spur gear with two spur gears 13 and 14 is trained. The output gear 8th is in the gearbox 11 of the drive attachment 7 arranged. The said transmission housing 11 is formed in the illustrated embodiment bivalves. A housing lower shell 15 is in the manner mentioned on the motor unit 2 attachable and can by a housing upper shell 16 be closed.

The housing lower shell 15 includes suitable storage means 17 for the storage of the transmission elements of the output gear 8th , It is understood that also the upper housing shell 16 may have corresponding bearing means to the spur gears 13 and 14 to store.

The Stirnzahnradgetriebestufe shown in the figure 12 It allows, in a simple manner, the gear ratio of the output gear 8th to change without the center distance of the spur gears 13 and 14 and thus the corresponding storage means 17 would have to be changed. For example, can be changed from a reduction to a translation by a smaller spur gear 13 through a larger spur gear and a larger spur gear 14 is replaced by a smaller spur gear.

The output gear 8th can engine side with the engine output shaft 4 get connected. The spur gear 14 can do this with the engine output shaft 4 rotatably connected when the gear attachment to the motor unit 2 is put on. On the output side drives the spur gear 13 a transmission output shaft 18 on, on which said spur gear 13 sits and the out of the housing upper shell 16 emerges from the front side or through an exit recess 19 is accessible from the outside to be coupled to the Torbewegungselement.

Between said spur gear 13 and the transmission output shaft 18 An unlocking clutch is provided through which the transmission output shaft 18 opposite the motor unit 2 can be unlocked. In the illustrated embodiment, the coupling element of the Entriegelungskupplung 20 in the transmission output shaft 18 or the spur gear 13 integrated. As the figure shows, the unlocking clutch comprises 20 a feather key 21 in a feather key recess 22 in the transmission output shaft 18 axially displaceable, but rotatably mounted. At the spur gear 13 In this case, a key recess is likewise provided on the front side in the inner recess, so that, depending on the position of the key 21 the spur gear 13 with the transmission output shaft 18 is rotatably locked or released from this and is rotatable. The feather key 21 is doing of a spring device in the form of a compression spring 23 biased into its locking position. The named compression spring 23 is in an axial bore inside the transmission output shaft 18 added. On the opposite side of the compression spring 23 sits in the same axial bore in the transmission output shaft 18 an actuating pin 24 , the front side of the transmission output shaft 18 protrudes and through an actuating recess in the housing lower shell 15 also emerges from this or from the outside of the housing lower shell 15 Her is operable. For actuating the actuating pin 24 and thus the unlocking clutch 20 is a release lever 25 provided on the transmission housing 11 , in particular on the housing lower shell 15 , stored. The release lever 25 is pivotably and / or displaceably mounted between a non-engagement position and an engagement position, wherein it is in the latter engagement position with the actuating pin 24 engages and this in the transmission output shaft 18 pushes in, so that the feather key 21 is pressed into its non-engaged position.

The housing lower shell 15 advantageously comprises a plurality of bearing means for the release lever 25 so this in different Alignments on the outside of the housing lower shell 15 can be mounted.

The position of the release lever 25 is from a limit switch 26 monitored, the at a suitable point fixed to the transmission housing 11 is mounted. Will the release lever 25 moved to its unlocked position, this detects the limit switch 26 , which can give a corresponding message to the control device of the door drive, in particular the power supply for the entire door drive 1 , in particular the motor unit 2 , can interrupt.

Furthermore, in the drive attachment 7 a path detection device 27 integrated, which is a pulse disc 28 having, which with the transmission output shaft 18 is coupled in a predetermined manner according to the rotation of the transmission output shaft 18 rotates. In the illustrated embodiment, the pulse disc sits 28 advantageously directly against rotation on the transmission output shaft 18 , By coupling the pulse disc 28 with the transmission output shaft 18 knows the wayfinding device 27 always, especially when disengaged unlocking clutch 20 , in which position the transmission output shaft 18 and thus the gate to be driven is located. The pulse disc 28 interacts with a pulse reader, which advantageously also in the interior of the transmission housing 11 of the drive attachment 7 is housed. The path detection device 27 is as well as the limit switch 26 in a manner not shown with the control device of the door drive 1 connected.

The transmission output shaft 18 has frontal with her from the housing upper shell 16 emergent end coupling means for coupling to a gate shaft, not shown in the figure. In the area of the exit of the transmission output shaft 18 from the gearbox 11 is on the gearbox 11 a damping device 29 attached to intercept drive shocks. As the figure shows, the damping device comprises 29 a damping element 30 that basically can be designed differently. In the illustrated embodiment, the damping element 30 formed by a spring. The damping element 30 is attached to a damping element carrier, which in the illustrated embodiment as a damping plate 31 is trained. The damping plate 31 sits in the area of the outlet of the transmission output shaft 18 on the housing upper shell 16 and has its own recess 32 through which the transmission output shaft passes 18 can extend. The damping plate 31 is by means of a screw connection 33 rotationally fixed to the transmission housing 11 fixable. Advantageously, the holes 34 in the damping plate 31 and / or in the housing upper shell 16 so formed or distributed that the damping plate 31 in a plurality of mutually rotated positions on the transmission housing 11 is fastened.

2 shows a further advantageous embodiment of a door drive, the in many respects the door drive 1 corresponds and has corresponding components, so that corresponding components the same reference numerals as in 1 are used and to that extent referred to the preceding description. Essentially, the design differs 2 in the training of the connection means of the drive attachment 7 for attachment to the motor unit 2 and in a motor side between the drive attachment 7 and the motor unit 2 arranged damping element.

In particular, the drive attachment 7 , as 2 shows, by a quick locking device 36 on the motor unit 2 fixable. The quick lock device 36 includes a bayonet lock 37 , by means of which the drive attachment 7 by combining an axial movement substantially parallel to the engine output shaft 4 and a rotational movement thereof to the motor unit 2 is positively coupled. Advantageously, only a fairly small rotational movement, for example, by a rotation angle of less than π, is sufficient.

As 2 shows includes the bayonet lock 37 a twist-lock plate 41 with radially projecting engagement arms or claws 38 wherein said rotary locking plate 41 has a central recess, by means of which they via the engine output shaft 4 slidable. The mentioned rotary locking plate 41 can be on the motor unit 2 , in particular the housing 6 the motor unit 2 , Are rotatably mounted, namely about a rotation axis parallel, in particular coaxial with the engine output shaft 4 , In the illustrated embodiment, the rotary locking plate 41 through a spacer plate 42 on the motor unit 2 fixable to the housing itself 6 the motor unit 2 is screwed. The twist lock plate 41 is opposite the spacer plate 42 rotatable.

On the other hand, the bayonet closure includes 37 on the housing shell 15 of the drive attachment 7 in the drawing not shown engagement recesses 39 , with the aforementioned engagement claws 38 the pivot lock plate 41 cooperate and are adapted to these. For fastening the drive attachment 7 this is only in the axial direction parallel to the engine output shaft 4 on the motor unit 2 set, with the engagement claws 38 in the engagement recesses 39 retract. Then, a lock can only by a relative rotation of engagement claws 38 and engagement recesses 39 be effected.

As 2 continues shows, sitting between the engine unit 2 and the drive attachment 7 the damping element 40 formed in the illustrated embodiment in the form of an annular damper disc through which the engine output shaft 4 extends. Specifically, said damping element sits 40 while in the illustrated embodiment between the above fixed to the motor unit 2 connectable spacer plate 42 and the housing shell 15 of the drive tower 7 , As 2 shows are in the spacer plate 42 Dämpfungsausnehmungen 43 formed in the engagement projections 44 on the damping element 40 engage so that the damping element 40 positive fit on the spacer plate 42 is held. The said engagement projections 44 also extend to the housing shell 15 of the drive attachment 7 towards where they intervene in likewise formed Dämpfungsausnehmungen. About the aforementioned positive engagement means 44 is the damping element 40 both radially and circumferentially effective. The damping element 40 consists of a suitable shock and / or vibration damping material.

Claims (26)

Door operator for a garage, garden, hall or industrial door, with a motor unit ( 2 ), which has a drive motor ( 3 ) and an engine output shaft ( 4 ), an output gear ( 8th ), the input side with the engine output shaft ( 4 ) is connectable and the output side a transmission output shaft ( 18 ) for driving a Torbewegungselements, in particular a Torwelle having, a Entriegelungskupplung ( 20 ) for unlocking the engine output shaft ( 4 ) relative to the door movement element, as well as at least one damping element ( 30 . 31 ; 40 ) for damping drive shocks, characterized in that the output gear ( 8th ) one of the motor unit ( 2 ) separately formed transmission housing ( 11 ) and with the Entriegelungskupplung ( 20 ) and the damping element ( 30 . 31 ) modularly forms a separate drive attachment, on the one hand to the motor unit ( 2 ) and on the other hand connectable to the Torbewegungselement. Door drive according to the preceding claim, wherein a displacement detection device ( 27 ), preferably a pulse disc ( 28 ), for detecting the position of the door in the drive attachment ( 7 ), in particular in the interior of the transmission housing ( 11 ) of the top gear is added. Door drive according to one of the preceding claims, wherein a Entriegelungsertassungseinrichtung, in particular a limit switch ( 26 ), for detecting the unlocking position of the Entriegelungskupplung ( 20 ) and / or to shut off the power supply of the door drive when unlocking the door drive in the drive attachment ( 7 ), in particular on the transmission housing ( 11 ) of the top gear is attached. Door drive according to one of the preceding claims, wherein the motor unit ( 2 ) and the drive attachment separately formed housing ( 6 . 11 ), on the one hand the function blocks of the motor unit ( 2 ) and on the other hand the function blocks of the drive attachment ( 7 ) take up. Door drive according to one of the preceding claims, wherein two separate gear stages are provided, of which the one in the motor unit ( 2 ) and the other in the drive attachment ( 7 ), wherein preferably the two gear stages ( 5 ; 13 . 14 ) are formed differently from each other. Door drive according to one of the preceding claims, wherein the transmission housing ( 11 ) of the drive attachment ( 7 ) of two half-shells ( 15 . 16 ), which are settleable and of which the one connecting means ( 9 ) for connecting the motor unit ( 2 ) and the other connection means ( 10 ) for supporting the driving force. Door drive according to one of the preceding claims, wherein the drive attachment ( 7 ) on the motor connection side different and / or variable connection means ( 9 ) for connection to various motor units and / or for connection to a motor unit ( 2 ) in different positions relative thereto. Door drive according to one of the preceding claims, wherein between the motor unit ( 2 ) and the drive attachment ( 7 ) a quick locking device for locking the drive attachment ( 7 ) on the motor unit ( 2 ) is provided. Door drive according to the preceding claim, wherein the quick locking device ( 36 ) on the motor unit ( 2 ) provided intervention means ( 28 ) and adapted thereto, on the drive attachment ( 7 ) provided intervention means ( 29 ), which are brought into relative positive engagement by rotation relative to each other. Door drive according to the preceding claim, wherein the engagement means ( 28 . 29 ) to one to the engine output shaft ( 4 ) parallel rotation axis are rotatable and lockable. Door drive according to one of the three preceding claims, wherein the Schnellverriegelungsvor direction ( 36 ) a bayonet closure ( 37 ) having. Door drive according to one of the preceding claims, wherein the drive attachment ( 7 ) has on the output side different and / or variable connection means for connection to different door movement elements and / or for connection to a door movement element in different orientations for this purpose. Door drive according to one of the preceding claims, wherein the output gear ( 8th ) a replaceable gear stage ( 12 ), which is replaceable by a gear stage with deviating transmission or reduction ratio. Door drive according to the preceding claim, wherein the gear stage ( 12 ) a pair of spur gears ( 13 . 14 ). Door drive according to the preceding claim, wherein the pair of spur gears ( 13 . 14 ) via storage means ( 17 ) on the same gear housing shell ( 15 ) is supported. Door drive according to one of the preceding claims, wherein the at least one damping element ( 30 ) on a damping element carrier ( 31 ) is arranged, which is releasably connected to the transmission housing ( 11 ) of the drive attachment ( 7 ) connectable, preferably on an outer side of the transmission housing ( 11 ) is attachable. Door drive according to the preceding claim, wherein the damping element carrier from a damping plate ( 31 ), the front side in the region of the outlet of the transmission output shaft ( 18 ) from the transmission housing ( 11 ) on said transmission housing ( 11 ) is releasably secured and radially from the transmission output shaft ( 18 ) spaced damping element receptacle ( 35 ) owns. Door drive according to one of the preceding claims, wherein the damping element carrier ( 31 ) and / or the transmission housing ( 11 ) different and / or variable connection means ( 33 ) for connecting the damping element carrier ( 31 ) to the transmission housing ( 11 ) in several positions. Door drive according to one of the preceding claims, wherein the at least one or a further damping element ( 40 ) between the drive attachment ( 7 ) and the motor unit ( 2 ) is provided. Door drive according to the preceding claim, wherein said damping element ( 40 ) by the quick locking device ( 36 ) between the drive attachment ( 7 ) and the motor unit ( 2 ) is attachable. Door drive according to one of the two preceding claims, wherein said damping element ( 40 ) positive connection means for positive connection with the motor unit ( 2 ) and / or with the drive attachment ( 7 ) having. Door drive according to one of the preceding claims, wherein said damping element ( 40 ) relative to the engine output shaft ( 4 ) of the motor unit ( 2 ) radially effective and / or circumferentially about the engine output shaft ( 4 ) has effective damping means. Door drive according to one of the preceding claims, wherein said damping element ( 40 ) forms an annular damping disc, through which the engine output shaft ( 4 ). Door drive according to one of the preceding claims, wherein the unlocking coupling ( 20 ) between the transmission output shaft ( 18 ) and one in the transmission housing ( 11 ) received gear ( 13 ) of the output gear ( 8th ) is arranged. Door drive according to one of the preceding claims, wherein the unlocking coupling ( 20 ) one in the transmission output shaft ( 18 ) at least partially slidably received actuating pin ( 24 ), which is arranged by a mounted on the gear housing outside actuator ( 25 ) is operable. Door drive according to one of the preceding claims, wherein the motor unit ( 2 ) a gear stage ( 5 ), preferably a worm gear or a bevel-helical gear, having an electric motor shaft with the engine output shaft ( 4 ) connects.