DE102018218311B3 - Fluid-operated rotary drive and rotary drive arrangement equipped with it - Google Patents

Abstract

A fluid-operated rotary drive (2) of a double-acting type is proposed, which has a drive housing (4) in which two drive units (22, 23) which are in meshing engagement with an output shaft (13) are arranged. Each drive unit (22, 23) has a drive piston (24) which, together with an axially opposite end cover (7, 9) of the drive housing (4), delimits an outer drive chamber (26, 27). The end covers (7, 9) and the drive pistons (24) are provided with relief structures (39, 43) on the mutually facing inner and outer end faces (38, 42). In each outer drive chamber (26, 27) there are a cover insert (46) and a piston insert (47), the cover insert (46) in the relief structure (39) of the end cover (7, 9) and the piston insert (47) in the Relief structure (43) of the drive piston (24) can be used or is used. In this way, the dead volume of the outer drive chambers (26, 27) can be reduced. A rotary drive arrangement is also proposed, which also has at least one single-acting rotary drive (3), which in the end covers (7, 9) and in the drive units (22, 23) matches the double-acting rotary drive (2) and in the outer drive chambers ( 26, 27) is equipped with compression spring devices.

Description

The invention relates to a fluid-operated rotary drive of a double-acting type, with a drive housing having a longitudinal axis, which has an end cover on both end faces and in which two drive units each having a drive piston are arranged axially displaceably and in meshing engagement with an output shaft accessible from outside the drive housing stand, between the two drive pistons an inner drive chamber and between each drive piston and the axially opposite end cover a spring device-free outer drive chamber are formed, and these drive chambers can be acted upon by a fluid fluid system of the rotary drive in such a way controlled with a drive fluid that the two drive units for opposite linear drive movements are drivable, from which a rotational output movement of the output shaft results, each end cover on its one outer drive chamber delimiting inner end face and each drive piston on its outer end face delimiting an outer drive chamber has a relief structure having at least one axial depression.

One from the EP 0 092 987 A1 Known fluid-operated rotary drive of this type is of a double-acting type and enables the generation of a rotary output movement of its output shaft in both possible directions of rotation by means of an active fluid application by a drive fluid. The rotary drive has a drive housing, in which two axially successively arranged drive units are arranged axially displaceably, which engage with each other via a rack and pinion connection, so that the linear movements of the drive units are converted into a rotary output movement of the output shaft. Each drive unit has a drive piston, the two drive pistons jointly delimiting an inner drive chamber. In addition, each of the two drive pistons delimits an outer drive chamber with an axially opposite end cover of the drive housing. The inner drive chamber and the two outer drive chambers can be acted upon in a controlled manner by the drive fluid through a fluid channel system formed in the drive housing, in order to produce opposite linear drive movements of the two drive units, from which the rotational output movement of the output shaft results. On the axially facing end faces, the drive pistons and the end caps are each provided with a relief structure which comprises at least one axial recess and can be used to accommodate return springs if use is to be made as a single-acting rotary drive. A comparable rotary actuator is from the DE 103 50 305 B4 known.

From the US 9 228 597 B2 a fluid-operated rotary actuator of a double-acting type is known, which has a similar structure to the rotary actuator according to DE 103 50 305 B4 which, however, contains a compression spring device in each of the two outer drive chambers, which is supported between an end cover and a drive piston in order to constantly act on the two drive units in the direction of a relative position approximated to one another. To actuate this single-acting rotary drive, only the inner drive chamber is actuated fluidically. In the depressurized state of the inner drive chamber, the drive units each assume an approximated first stroke end position, from which they can be moved into a second stroke end position lying on the opposite end cover by applying fluid to the inner drive chamber while overcoming the spring force of the compression spring devices. In order to allow a variation of the spring force, at least one spacer is inserted between the compression spring arrangement and the end cover as well as the drive piston. Depending on the number of spacers inserted, the spring tension varies.

The EP 0 040 976 A1 discloses a fluid-operated rotary actuator in a single-acting design. The rotary drive has two drive units which can be moved in opposite directions, each of which has a drive piston and a toothed rack which engages with an output shaft. Each drive piston, together with an opposite end cover, delimits an outer drive chamber in which a compression spring is received, which is supported between the drive piston and the end cover. The drive units are biased into an approximated basic position by the compression springs. Each end cover has a recess facing the drive piston into which a stop pin attached to the drive cover projects.

The AT 364 968 B describes a double-acting rotary drive with a drive unit arranged in a drive housing, which has a drive piston and a toothed rack that is in meshing engagement with a drive shaft. The piston separates two drive chambers from each other, which can be acted upon by a fluid pressure medium in order to move the drive unit back and forth to rotate the output shaft. By replacing the end cover with a different end cover, a compression spring between the end cover and the drive piston is used, the double-acting rotary actuator can be converted into a single-acting actuator.

WO 2016/202 354 A1 describes a fluid-operated rotary drive which has a drive housing in which two drive units are arranged so as to be movable in opposite directions, each of which is in meshing engagement with a drive shaft via a toothed rack. Each drive unit has a drive piston, the two drive pistons jointly delimiting an inner drive chamber and, moreover, each drive piston delimiting an outer drive chamber together with an opposite end cover of the drive housing. Controlled fluid application to the drive chambers enables double-acting operation of the rotary drive. The drive pistons and the end caps each have a relief structure with several depressions on the mutually facing end faces.

From the EP 2 873 871 A1 a fluid-operated rotary drive device is known which has two drive units accommodated in separate spaces of a drive housing and which are in meshing engagement with a drive shaft extending between them. Both drive units have two piston-like head sections on the end face, which can be acted upon in a controlled manner with a fluid pressure medium in order to displace the drive units in opposite directions. The two spaces are closed on both ends by a housing cover, the housing covers arranged on one side having a recess axially on the inside, into which an end position damping means is inserted.

One from the EP 2 495 450 A1 Known fluid-operated rotary drive device also has two drive units which are accommodated in a linearly displaceable manner in separate spaces of a drive housing and are each in meshing engagement with a drive shaft. By means of controlled fluid application, they can be driven to a reciprocating linear movement in opposite directions. Each drive unit has two opposing head sections which, together with an opposite end cover, delimit a drive chamber. One of the head sections of each drive unit has a blind hole-like recess, into which an elastic buffer element serving to cushion the end position is inserted.

The invention also relates to a rotary drive arrangement which has a plurality of fluid-operated rotary drives, among which there is at least one double-acting rotary drive and at least one single-acting rotary drive, each of which has a drive housing having a longitudinal axis, which has an end cover on each end face and in which two Drive units each having a drive piston are arranged axially displaceably, which are in meshing engagement with an output shaft accessible from the outside of the drive housing and which can be driven by means of a fluid channel system of the rotary drive through controlled fluid application to opposite linear drive movements, from which a rotary output movement of the output shaft results, between which an inner drive chamber for the two drive pistons and an outer drive chamber between each drive piston and the adjacent end cover are formed, with each end cover on its inner end face delimiting an outer drive chamber and each drive piston on its outer end face delimiting an outer drive chamber has a relief structure which has at least one axial recess, one in each case in the outer drive chambers of the single-acting rotary drive with respect to the End cover and the drive piston supporting compression spring device is arranged, while the outer drive chambers of the double-acting rotary drive do not contain any spring device, the single-acting rotary drive and the double-acting rotary drive being identical to one another both with regard to their end cover and with regard to their drive units.

Such a rotary drive arrangement contains, for example, a double-acting rotary drive according to the EP 0 092 987 A1 and a single-acting rotary actuator equipped with return springs also according to the EP 0 092 987 A1 . These fluid-operated rotary actuators of different types can be used both together and independently of one another.

The invention has for its object to take measures that enable inexpensive manufacture and efficient use of a double-acting rotary actuator and a rotary actuator arrangement equipped with it.

To solve this problem, it is provided in a fluid-operated rotary drive of a double-acting type of the type mentioned that in each outer drive chamber a cover insert part inserted into the relief structure of the inner end face of the end cover or designed for insertion into this relief structure and one into the relief structure of the outer end face of the drive piston inserted or configured for insertion into this relief structure.

The insert parts arranged in a respective outer drive chamber, on the one hand a cover insert part and on the other hand a piston insert part, result in a reduction in the dead volume in the controlled fluid application, which is accompanied by an alternating supply and discharge of the drive fluid used to generate the drive force. The drive fluid is in particular compressed air, but can also be formed by another gaseous or by a liquid pressure medium. Without the existing insert parts, the drive fluid fed in to generate a drive force would also have to fill the partial volume of the drive chambers resulting from the relief structures, which is prevented by the insert parts, since the same can be inserted or inserted into the relief structures. The insert parts reduce the dead volume in the outer drive chambers. By reducing the dead volume, on the one hand, the energy stored in the drive chambers during actuation until initiation of the drive movements is reduced, so that the subsequent drive movements take place with less force and the intensity of the impact of the drive units in the other stroke end position is minimized. This reduces the wear on the rotary drive and also on the component that is connected to the output shaft for its rotary actuation, for example a valve flap. The reduction in the dead volume is also associated with a reduction in air consumption and, accordingly, an energy saving when actuated with compressed air.

Fluid-operated rotary actuators of the single-acting type are often provided with relief structures in their drive pistons and in their end caps, through which one or more depressions are defined, into which a compression spring device causing spring return engages. Such a single-acting rotary drive can be converted very easily into a double-acting rotary drive according to the invention by removing the compression spring devices and replacing them with the insert parts. There is also the advantageous possibility of producing fluid-operated rotary actuators of the double-acting type and of the single-acting type using identical drive units and end caps, which are combined with the insert parts to form a double-acting rotary actuator and with compression spring devices to form a single-acting rotary actuator. With such a use of identical parts, a particularly efficient and cost-effective production of the different types of fluid-operated rotary drives is possible.

Advantageous developments of the invention emerge from the subclaims.

In one possible embodiment of the fluid-operated rotary drive, the cover insert part and the piston insert part arranged in the same drive chamber are combined in a single insert unit, so that they form firmly connected components of the insert unit. The cover insert part and the piston insert part are preferably integral components of a one-piece insert unit. The design as an insert unit means that when the rotary drive is actuated, there are axial relative movements between the insert unit on the one hand and the associated end cover and / or the associated drive piston on the other hand. If the drive unit assumes a second stroke end position approximated to the end cover, the insert unit plunges both into the relief structure of the end cover and into the relief structure of the drive piston and is consequently inserted into both relief structures. In an opposite first stroke end position of the drive unit, that is, when the drive piston is as far as possible from the opposite end cover, the insert unit only plunges into one of the two relief structures. If the insert unit is axially floating in the assigned outer drive chamber, it can even be completely out of engagement with the relief structures of both the drive piston and the end cover in the aforementioned first stroke end position of the drive unit.

An embodiment is considered to be particularly advantageous in which the cover insert part of the insert unit is inserted into the relief structure of the inner end face of the end cover and is fastened to the end cover, so that the relative position between the insert unit and the end cover does not change when the fluid-operated rotary drive is actuated. On the other hand, the component of the insert unit that defines the piston insert part alternately comes into and out of engagement with the relief structure of the drive piston during the drive movement of the associated drive unit, so that the piston insert part is out of engagement with the relief structure of the drive piston in a first stroke end position of the drive unit that is removed from the end cover, and in one engages the end cover approximated second stroke end position of the drive unit in the relief structure of the drive piston and is therefore inserted.

It is advantageous if the insert unit is attached to the end cover so that it does not follow the movement of the drive unit and the mass moved is relatively small. The insert unit is preferably fastened non-positively and / or positively and / or integrally in the relief structure of the associated end cover via the cover insert part.

Of course, there is the alternative possibility of fixing the insert unit to the drive unit so that it follows the drive movement relative to the drive housing.

In a likewise advantageous embodiment of the fluid-operated rotary drive, the cover insert part and the piston insert part arranged in the same outer drive chamber are designed as separate components which are not connected to one another.

With this configuration, there is in principle the possibility of arranging both insert parts in an axially floating manner in the outer drive chamber, so that they have the option of alternately intervening in or stepping out of the associated relief structure depending on the drive movement of the assigned drive unit. It is also possible to fix only one of the two insert parts arranged in the same outer drive chamber to the associated end cover or drive piston and to arrange only the other insert part in an axially floating manner in the outer drive chamber.

It is considered to be particularly expedient in the case of a separate design of the cover insert part and the piston insert part if each cover insert part is inserted into the relief structure of the inner end face of the associated end cover and is fastened to the end cover, each piston insert part also being inserted into the relief structure of the outer end face of the associated drive piston inserted and attached to the drive piston. When the fluid-operated rotary drive is actuated, the cover insert part remains fixed with respect to the end cover and consequently with the drive housing, while the piston insert part is fixed with the drive unit and takes part in its drive movement.

In order to fix them, the cover insert part and / or the piston insert part can be fastened non-positively and / or positively and / or integrally in the respectively assigned relief structure.

On their mutually facing end faces, the cover insert parts and the piston insert parts are preferably flat and without any structuring. These end faces run in particular in a plane perpendicular to the longitudinal axis. This enables the drive unit to approach the opposite end cover without leaving a relevant dead space in the outer drive chamber.

Each cover insert and / or each piston insert is preferably plate-shaped or disk-shaped. The cover insert part and / or the piston insert part preferably has a circular outer contour, which, however, can be stepped in the circumferential direction.

Each relief structure has, for example, only a single axial depression or else it has a plurality of axial depressions which are arranged next to one another at a distance. A plurality of axial depressions can in particular be arranged in such a way that they are placed around the central longitudinal axis of the drive housing, in particular lying on a common circular line.

The insert parts are preferably designed such that they completely fill the at least one depression of the opposite relief structure in the state inserted into the relief structure. This results in an optimal reduction in the dead volume regardless of whether there is a sealed or an unsealed connection between the insert part and the end cover or the drive piston. The connection between the insert part inserted into a relief structure and the component having the relief structure is preferably implemented without sealing measures. Nevertheless, such sealing measures are fundamentally possible.

A design is considered to be optimal in which each cover insert part on its outer end face facing the adjacent end cover has a shape that is complementary to the relief structure of the end cover, and each piston insert part also has a shape on its inner end face facing the adjacent drive piston that is complementary to the relief structure of the drive piston. It is also possible to implement this complementary shape only in the cover insert part or only in the piston insert part.

A shape complementary to a relief structure manifests itself in particular in a shape of the insert part with a negative image of the opposite relief structure.

Above all to reduce the manufacturing costs and the weight, it is expedient to manufacture the insert parts and the piston insert parts from a plastic material.

The cover insert part and / or the piston insert part can in principle be designed as a hollow body. However, they are preferably each designed as a solid material body, since high stability can be ensured in this way regardless of the level of the fluid pressures prevailing in the outer drive chambers.

The drive housing preferably contains a tubular housing middle part, in which the output shaft is rotatably mounted about its longitudinal axis and one of the end covers is mounted on each of the two end faces, in particular by means of fastening screws. The output shaft expediently passes through the interior of the central housing part and is rotatably supported in the wall of the central housing part.

The relief structures of the end cover and the drive piston preferably each have at least one recess which, when the cover insert parts and the piston insert parts are removed, are suitable for receiving an axial end section of a compression spring device arranged in the associated outer drive chamber and pressing the drive unit away from the end cover. This offers the advantageous possibility of converting the double-acting rotary drive into a single-acting rotary drive by removing the insert parts and installing previously non-existent compression spring devices.

The object on which the invention is based is achieved in connection with a rotary drive arrangement of the type mentioned at the outset, which has at least one double-acting rotary drive and at least one single-acting rotary drive, the single-acting rotary drive and the double-acting rotary drive being identical to one another both with regard to their end covers and with regard to their drive units , solved by the fact that in each outer drive chamber of the double-acting rotary drive a cover insert part inserted into the relief structure of the inner end face of the end cover or designed for insertion into this relief structure and a cover insert part inserted into the relief structure of the outer end face of the drive piston or designed for insertion into this relief structure Piston insert are arranged.

In this way, there is the advantageous possibility already mentioned at the outset of producing different types of fluid-operated rotary drives inexpensively using identical parts.

The single-acting rotary drive and the double-acting rotary drive expediently have not only identically designed end covers on the housing side, but also overall identical drive housings.

The double-acting rotary drive of the rotary drive arrangement is preferably designed in the sense explained above.

• 1 eine bevorzugte Ausführungsform des erfindungsgemäßen fluidbetätigten Drehantriebes vom doppeltwirkenden Typ in einer perspektivischen Darstellung,
• 2 den Drehantrieb aus 1 in einer perspektivischen Explosionsdarstellung,
• 3 eine perspektivische Darstellung eines fluidbetätigten Drehantriebes eines einfachwirkenden Typs, der gemeinsam mit dem doppeltwirkenden Drehantrieb der 1 und 2 eine bevorzugte Drehantriebsanordnung bildet,
• 4 den einfachwirkenden Drehantrieb aus 3 in einer perspektivischen Explosionsdarstellung,
• 5 einen Längsschnitt des Drehantriebes der 1 und 2 gemäß Schnittlinie V-V aus 1,
• 6 einen weiteren Längsschnitt des Drehantriebes der 1 und 2 gemäß Schnittlinie VI-VI aus 1,
• 7 einen Längsschnitt des Drehantriebes der 3 und 4 gemäß Schnittlinie VII-VII aus 3,
• 8 einen weiteren Längsschnitt des Drehantriebes der 3 und 4 gemäß Schnittlinie VIII-VIII aus 3,
• 9 einen der 5 entsprechenden Längsschnitt eines fluidbetätigten Drehantriebes eines doppeltwirkenden Typs, dessen Aufbau abgesehen von einer modifizierten Ausgestaltung der Einsatzteile demjenigen der 1 und 2 entspricht, wobei die links der vertikalen Drehachse der Abtriebswelle abgebildete Antriebseinheit bei Einnahme einer ersten Hubendlage und die rechts der vorgenannten Drehachse angeordnete weitere Antriebseinheit bei Einnahme einer zweiten Hubendlage gezeigt ist,
• 10 ein bei den Ausführungsbeispielen der 1 und 2 verwendetes Deckeleinsatzteil in einer perspektivischen Einzeldarstellung,
• 11 das Deckeleinsatzteil aus 10 aus einem anderen Blickwinkel,
• 12 ein bei dem Ausführungsbeispiel der 1 und 2 verwendetes Kolbeneinsatzteil in einer perspektivischen Einzeldarstellung, und
• 13 das Kolbeneinsatzteil gemäß 12 aus einem anderen Blickwinkel.

The invention is explained in more detail below with reference to the accompanying drawing. In this show:

• 1 a preferred embodiment of the fluid-operated rotary actuator of the double-acting type according to the invention in a perspective view,
• 2nd the rotary drive 1 in an exploded perspective view,
• 3rd a perspective view of a fluid-operated rotary actuator of a single-acting type, which together with the double-acting rotary actuator 1 and 2nd forms a preferred rotary drive arrangement,
• 4th the single-acting rotary actuator 3rd in an exploded perspective view,
• 5 a longitudinal section of the rotary drive 1 and 2nd according to section line VV 1 ,
• 6 a further longitudinal section of the rotary drive 1 and 2nd according to section line VI-VI 1 ,
• 7 a longitudinal section of the rotary drive 3rd and 4th according to section line VII-VII 3rd ,
• 8th a further longitudinal section of the rotary drive 3rd and 4th according to section line VIII-VIII 3rd ,
• 9 one of the 5 corresponding longitudinal section of a fluid-operated rotary actuator of a double-acting type, the structure of which apart from a modified configuration of the insert parts that of 1 and 2nd corresponds to the drive unit shown on the left of the vertical axis of rotation of the output shaft when taking a first stroke end position and the other drive unit arranged on the right of the aforementioned axis of rotation when taking a second stroke end position,
• 10th one in the embodiments of 1 and 2nd used lid insert part in a perspective individual representation,
• 11 the lid insert 10th from a different perspective,
• 12th one in the embodiment of 1 and 2nd used piston insert part in a perspective view, and
• 13 the piston insert according to 12th from a different perspective.

The 1 and 2nd show one to a rotary drive arrangement 1 belonging fluid-operated rotary drive 2nd of a double acting type, which in To simplify the following, only as a double-acting rotary actuator 2nd referred to as. Also the 9 shows such a double-acting rotary actuator 2nd which also goes to the rotary drive assembly 1 can belong.

The 3rd and 4th preferably show one to the rotary drive arrangement 1 belonging fluid-operated drive 3rd of a single-acting type, which in the following is also only used as a single-acting rotary actuator for simplification 3rd referred to as.

As far as one or the "rotary actuator 2, 3" is mentioned in the following, the associated statements relate jointly to both the double-acting rotary actuator 2nd as well as the single-acting rotary drive 3rd .

The rotary drive 2nd , 3rd has a drive housing 4th that is a longitudinal extension along an imaginary longitudinal axis 5 Has. The drive housing 4th encloses an interior of the housing 6 .

The interior of the housing 6 is on the two axially oriented end faces of the drive housing 4th with one end cover each 7 , 9 locked. For better differentiation, the two end covers 7 , 9 in the following also as the first cover 7 and second end cover 9 designated. The drive housing preferably has 4th a tubular housing middle part 8th that is coaxial to the longitudinal axis 5 extends and on the two opposite ends of each one of the end caps 7 , 9 is mounted, in particular in a detachable manner and preferably with the aid of fastening screws. Thus, the interior of the housing 6 together from the middle part of the housing 8th and the two end caps 7 , 9 limited.

Between the middle part of the housing 8th and every end cover 7 , 9 is expediently a seal 10th inserted, at least in the double-acting rotary actuator 2nd .

Through the interior of the housing 6 extends through to the longitudinal axis 5 vertically aligned longitudinal axis 12th an output shaft 13 . The output shaft 13 is relative to the drive housing 4th about its longitudinal axis 12th rotatable so that the longitudinal axis 12th at the same time an axis of rotation 14 the output shaft 13 forms.

The output shaft 13 is by suitable pivot bearing devices 15 on the drive housing 4th rotatably mounted. The output shaft preferably extends 13 in itself with respect to the longitudinal axis 5 diametrically opposite wall sections of the middle part of the housing 8th , in the area of which one of the rotary bearing devices 15 is provided. Thus, the interior of the housing 6 from the output shaft 13 transverse to the longitudinal axis 5 traverses.

The output shaft 13 is from outside the drive housing 4th forth for tapping a rotary output movement 16 accessible. It has an example from the side of the drive housing 4th outstanding tap section 17th on which the rotary output movement 16 is tapped to twist any component, not shown. Such a component to be twisted is with the tap section 17th non-rotatably connectable. In a preferred application, the component to be rotated is a valve member of a valve used to control a fluid control, in particular a so-called process valve. The valve member can be, for example, a valve flap. The tap section 17th may differ from the illustrated embodiment in the drive housing 4th be sunk.

The rotary output movement 16 has two possible, opposite directions of rotation. Thus the output shaft 13 a back and forth rotary output movement 16 To run.

The output shaft 13 points to it in the housing interior 6 extending longitudinal section around the longitudinal axis 12th sprocket extending around 18th on. The ring gear is exemplary 18th in two in the axial direction of the longitudinal axis 12th spaced-apart gear ring sections 18a , 18b divided. However, it can also be undivided. The output shaft 13 thus forms a pinion overall.

In the interior of the housing 6 there are two in the axial direction of the longitudinal axis 5 relative to the drive housing 4th movable drive units 22 , 23 . The latter are also referred to below as the first drive unit for better differentiation 22 and as a second drive unit 23 designated. Every drive unit 22 , 23 is exemplary on the inner peripheral surface of the wall of the housing middle part 8th guided linearly displaceable.

Every drive unit 22 , 23 has a drive piston 24th . The two drive pistons 24th lie on each other in the axial direction of the longitudinal axis 5 opposite sides of the output shaft 13 . The drive piston is thus located 24th the first drive unit 22 between the output shaft 13 and the first end cover 7 while the drive piston 24th the second drive unit 23 between the output shaft 13 and the second end cover 9 is arranged.

Every drive piston 24th is slidably and sealingly on the inner peripheral surface of the tubular housing middle part 8th at.

The axially between the two drive pistons 24th lying length section of the housing interior 6 represents an inner drive chamber 25th . Anyone between a drive piston 24th and one of the two end covers 7 , 9 lying longitudinal sections of the housing interior 6 defines an outer drive chamber 26 , 27 , being between the drive piston 24th the first drive unit 22 and the first end cover 7 located outer drive chamber 26 hereinafter also referred to as the first outer drive chamber 26 is referred to as between the drive piston 24th the second drive unit 23 and the second end cover 9 located outer drive chamber 27 hereinafter also referred to as the second outer drive chamber 27 referred to as.

The inner drive chamber 25th is through the two drive pistons 24th from both outer drive chambers 26 , 27 separated in a fluid-tight manner. For this purpose, the drive piston points 24th on its radial outer circumference a slidably on the inner circumferential surface of the tubular housing middle part 8th adjacent seal.

Every drive unit 22 , 23 has one starting from its drive piston in the axial direction of the longitudinal axis 5 in the direction of the other drive piston 24th extending rack 28 . The two racks 28 extend in the region of opposite radial peripheral sides of the output shaft 13 on the output shaft 13 past. Every rack 28 has at her the output shaft 13 facing longitudinal side one in the axial direction of the longitudinal axis 5 extending toothing 32 each at right angles to the longitudinal axis 5 and parallel to the long axis 12th trending teeth. Every rack 28 stands with their interlocking 32 with the ring gear 18th the output shaft 13 in a gear mesh.

The gearing 32 every rack 28 is exemplary of two in the axial direction of the longitudinal axis 12th adjacent toothing sections 32a , 32b formed, each with one of the ring gear sections 18a , 18b comb. The gears 32 can also be undivided in each case.

The rotary drive 2nd , 3rd has a fluid channel system 33 that in the 6 and 8th is indicated by dash-dotted lines. The fluid channel system preferably runs 33 in the wall of the drive housing 4th .

A first sub-channel system 33a of the fluid channel system 33 has one on the outside of the drive housing 4th accessible first connection opening 34 and on the other hand opens into the inner drive chamber 25th a.

A second subchannel system 33b of the fluid channel system 33 has one on the outside of the drive housing 4th accessible second connection opening 34b and on the other hand opens into each of the two outer drive chambers 26 , 27 a.

Using the fluid channel system 33 is with the double-acting rotary actuator 2nd controlled fluid loading of the inner drive chamber 25th and the two outer drive chambers 26 , 27 possible by means of a drive fluid that is made available by a pressure source, not shown. The control is expediently carried out by means of a control valve device, also not shown. There is a possibility of the inner drive chamber 25th to ventilate and at the same time the two outer drive chambers 26 , 27 to vent, or vice versa. As a result, a pressure difference acts on each drive piston 24th , which has the consequence that the drive units 22 , 23 in each case a linear drive movement indicated by a double arrow 35 in the axial direction of the longitudinal axis 5 execute, always in opposite directions. Either the two drive units move 22 , 23 away from each other, the volume of the inner drive chamber 25th is enlarged, or they approach the volume of the inner drive chamber while decreasing 25th to each other. Since the driving force can be generated actively by fluid force in both directions of movement, one speaks of a double-acting actuation.

Due to the meshing engagement between the racks 28 and the ring gear 18th becomes the output shaft 13 due to the linear drive movements 35 of the drive units 22 , 23 to the rotary output movement 16 driven.

The double-acting rotary actuator 2nd has no spring device to cause the drive movements 35 . In none of the outer drive chambers 26 , 27 there is a spring device so that one can say that the outer drive chambers 26 , 27 are designed without spring means. Also in the inner drive chamber 25th no spring device is included. The drive movements 35 are only by the on the drive piston 24th generated fluidic pressure differences.

With the single-acting rotary drive 3rd are the drive movements 35 of the two drive units 22 , 23 also by controlled fluid application by means of the fluid channel system 33 provocable. However, this is only the one with the inner drive chamber 25th communicating first Subchannel system 33a used. About this first subchannel system 33a can in the inner drive chamber 25th prevailing fluid pressure can be varied. Only the driving force for the drive movements directed away from each other 35 are actively generated here by fluid power, so that one speaks of a single-acting actuation.

The two outer drive chambers 26 , 27 experienced when using the single-acting rotary actuator 3rd no controlled fluid exposure. The fluid pressure prevailing therein is kept essentially constant by the second connection opening 34b communicates with the atmosphere within the two outer drive chambers 26 , 27 the atmospheric pressure is constant.

To generate a counterforce that results from the fluid application of the inner drive chamber 25th resulting fluid force counteracts is in each outer drive chamber 26 , 27 of the single-acting rotary actuator 3rd one on the one hand on the assigned end cover 7 , 9 and on the other hand on the associated drive piston 24th supporting compression spring device 36 arranged. Through the two compression spring devices 36 the two drive units 22 , 23 constantly spring-loaded in the sense of mutual rapprochement. The result of this is that the internal drive chamber is depressurized by appropriate activation 25th both drive units 22 , 23 be pressed into a first stroke end position, which from the 7 and 8th can be seen and in the inner drive chamber 25th has a minimal volume.

By feeding a drive fluid under the appropriate pressure into the inner drive chamber 25th can the drive units 22 , 23 to drive movements that move away from each other 35 are driven until they assume a second stroke end position, in which they are as far as possible on the respectively assigned end cover 7 are approximated. Then the inner drive chamber 25th Vented again, the two drive units sweep 22 , 23 by the spring force of the two compression spring devices 36 back to the first stroke end position.

With the double-acting rotary actuator 2nd can the two drive units 22 , 23 also in each case as close as possible to each other 5 and 6 and from the left half of the picture 9 apparent first stroke end position or in a second stroke end position as far apart as possible. The second stroke end position is dash-dotted in the 5 and also in the right half of the picture 9 illustrated. For 9 is to say that the two drive units 22 , 23 of course, always occupy either the first stroke end position or the second stroke end position at the same time and the two different stroke end positions are shown here for explanatory purposes only.

The compression spring device 36 is made up of several individual compression springs in the exemplary embodiment 37 together, with parallel spring action in the associated outer drive chamber 26 , 27 are arranged. The plurality of compression springs are preferred 37 around the center of the drive housing 4th aligned longitudinal axis 5 arranged around distributed. In particular, they lie on one to the longitudinal axis 5 concentric circular line. According to a non-illustrated embodiment, each compression spring device can 36 also have only a single, appropriately larger compression spring.

The compression springs are designed in particular as helical springs.

Every end cover 7 , 9 has an adjacent outer drive chamber 26 , 27 delimiting inner face 38 . Every drive piston 24th has one of the outer drive chambers defined by it 26 , 27 facing outer face 42 . Every end cover 7 is on the inner face 38 with a relief structure 39 provided in the following for better differentiation also as an internal relief structure 39 referred to as. Every drive piston 24th is on its outer face 42 also with a relief structure 43 provided, in the following also for better differentiation as an outer relief structure 43 referred to as.

Any of the aforementioned relief structures 39 , 43 has several examples for the assigned outer drive chamber 26 , 27 open axial recesses 44 . These several wells 44 are in one to the longitudinal axis 5 right-angled plane spaced from each other, with adjacent recesses 44 and possibly also within the wells 44 one or more axial elevations 45 the relevant relief structure 39 , 43 available.

With the single-acting rotary drive 3rd take over the relief structures 39 , 43 at least among other things the task of the at least one end section of the compression spring device facing them 36 to record. This will make the compression spring device 36 transverse to the longitudinal axis 5 fixed. In addition, the compression spring device 36 in the second stroke end position of the assigned drive unit 22 , 23 from the axial depressions 44 be recorded without the drive movement 35 to block. The axial depth of the depressions is preferred 44 chosen so that the drive units 22 , 23 in the second stroke end position on opposite end cover 7 , 9 can rest without the compression spring device 36 was compressed to block.

Like the one in particular 3rd and 4th the inner and outer relief structures can be seen 39 , 43 preferably designed so that they for each of the individual compression springs 37 its own axial depression 44 contain.

With the double-acting rotary actuator 2nd which is used to actuate the drive units 22 , 23 has no spring device, the inner and outer relief structures 39 , 43 Although also present, however, due to special measures, it does not have a disadvantageous effect on the dead volume of the outer drive chambers 26 , 27 out. The special measures are that in each outer drive chamber 26 , 27 one to the assigned end cover 7 , 9 axially opposite cover insert 46 and an associated drive piston 24th axially opposite piston insert 47 are arranged, the cover insert 46 for insertion in the inner relief structure 39 the assigned end cover 7 , 9 and the piston insert 47 for insertion in the outer relief structure 43 of the adjacent drive piston 24th are trained.

The following only collectively as insert parts 46 , 47 designated lid insert parts 46 and piston insert parts 47 are designed and arranged so that they are at least in the second stroke end position of the drive piston 24th into the relief structures 39 , 43 are used.

The insert parts are preferred 46 , 47 designed in a relief structure 39 , 43 used state all depressions of the relief structure 39 , 43 to complete.

Each lid insert preferably has 46 on the one end cover 7 , 9 facing outer end face an outer relief structure 52 that complement the internal relief structure 39 of the opposite end cover 7 , 9 is trained. In a comparable manner, each piston insert part preferably has 47 on the drive piston 24th facing inner end face an inner relief structure 53 that are complementary to the outer relief structure 43 of the adjacent drive piston 24th is trained.

This advantageously enables the mutually interlocking state of the mutually facing inner and outer relief structures 39 , 52 ; 53 , 43 all axial depressions 44 of the relief structures 39 , 43 the end cover 7 , 9 and the drive piston 24th through one of one of the insert parts 46 , 47 formed solid are filled.

The complementary design of the relief structures 39 , 43 , 52 , 53 is expressed in the illustrated embodiment in that the relief structures 52 , 53 the lid insert 46 and the piston insert 47 over one of the number of axial depressions 44 corresponding number of axial projections 54 have, the axial projections 54 each in one of the axial recesses 44 can engage or immerse axially.

Corresponding to that in the 1 , 2nd , 5 , 6 and 10th to 13 Illustrated embodiment, it is advantageous if each in an outer drive chamber 26 , 27 arranged lid insert 46 separate from that in the same outer drive chamber 26 , 27 arranged piston insert 47 is trained. Every cover insert 46 is in the inner relief structure 39 the assigned end cover 7 , 9 used and attached to the end cover so that it can not perform an axial relative movement in this regard. Each piston insert is in a comparable manner 47 in the outer relief structure 43 of the adjacent drive piston 24th used and also on the drive piston 24th attached so that there is no axial relative position with respect to the drive piston 24th can perform and any drive movement 35 of the drive piston 24th participates.

The attachment of the insert parts 46 , 47 on the assigned end cover 7 , 9 or drive piston 24th preferably takes place inside the relief structures 39 , 43 and especially through the paired interaction of these relief structures 39 , 43 with the relief structures 52 , 53 the insert parts 46 , 47 .

Different fastening methods are alternatively or cumulatively possible. Suitable fastening methods consist of a non-positive fastening and / or a positive fastening and / or a material fastening. The components used one inside the other are for example clamped together and / or locked together and / or glued together.

Of course there is also the possibility of insert parts 46 , 47 outside the relief structures 39 , 43 on the assigned end cover 7 , 9 or drive piston 24th to fix, for example by means of one or more fastening screws.

So that the insert parts 46 , 47 the available axial stroke of the drive units 22 , 23 does not affect, it is advantageous if they on their mutually facing axial end faces 55 , 56 are unstructured and level, so that the face in question 55 , 56 one perpendicular to the longitudinal axis 5 extending flat surface represents. This is the case in the illustrated embodiment.

The inner relief structure is preferably located 39 only in that area of the inner face 38 the end cover 7 , 9 that directly the outer drive chamber 26 , 27 limited.

The inner front surface is exemplary 38 each end cover 7 , 9 one the inner relief structure 39 framing edge-side surface section 57 on an annular face 58 of the middle part of the housing 8th is present.

Every cover insert 46 is preferably designed so that it is in the inner relief structure 39 inserted state at least substantially axially flush with the edge-side surface section 57 completes. The flat front surface runs as an example 55 of the inner relief structure 39 inserted lid insert 46 at least essentially in one plane with the edge-side surface section 57 .

At the drive piston 24th has the outer relief structure 43 expediently a smaller diameter than the drive piston 24th , with the outer face 42 each drive piston 24th one the outer relief structure 43 framing edge-side surface section 62 with which in the outer relief structure 43 inserted piston insert 47 at least essentially axially flush. The flat end face preferably runs 56 of in the outer relief structure 43 used piston insert 47 in a common plane with the edge-side surface section 62 .

The cover insert parts preferably exist 46 and / or the piston insert parts 47 made of plastic material. They are expediently each designed as a solid material body. In principle, however, they could also be designed as a hollow body which has at least one cavity which is enclosed in a fluid-tight manner by an outer wall.

Each lid insert is preferred 46 and / or each piston insert 47 plate-shaped or disc-shaped. It preferably has a circular outer contour, which, however, can be stepped in the circumferential direction. Starting from the other insert part 46 , 47 facing end face 55 , 56 can the with respect to the longitudinal axis 5 peripheral outer contour of the cover insert part oriented radially outwards 46 and / or the piston insert part 47 towards the same insert 46 , 47 arranged relief structure 52 , 53 rejuvenate.

Both the inner relief structure is preferred 39 the end cover 7 , 9 as well as the outer relief structure 43 the drive piston 24th radially outside with one around the longitudinal axis 5 extending around, radially inwardly oriented peripheral boundary surface 48 provided that the lid insert used in each case 46 or piston insert 47 radially surrounds all around.

According to one in 9 illustrated embodiment, each lid insert 46 in the same outer drive chamber 26 , 27 arranged piston insert 47 in a single unit 63 be summarized. The insert unit 63 has two axially adjacent longitudinal sections, one of which is the cover insert 46 and the other the piston insert 47 forms. In 9 the transition area between the two components is indicated by dot-dash lines at 64. The insert unit is preferred 63 a one-piece body that holds both the lid insert 46 as well as the piston insert 47 forms.

The stake units 63 are expedient with their cover insert 46 in the inner relief structure 39 the end cover 7 , 9 inserted and on the assigned end cover 7 , 9 attached. This is the inner relief structure 39 filled in and takes part in the fluid exchange in the controlled fluid application of the outer drive chamber 26 , 27 not part. The stake units 63 keep the drive movement 35 of the drive units 22 , 23 their relative position with respect to the drive housing 4th constant at.

The insert units fixed in this way 63 protrude with their piston insert 47 axially into the associated outer drive chamber 26 , 27 inside. As long as the drive units 22 , 23 are in the approximate first stroke end position, the piston insert part engages 47 in the opposite outer relief structure 43 of the drive piston 24th not one, since the same to the piston insert 47 the insert unit 63 is axially spaced.

Has the drive unit 22 , 23 in the right half of the picture 9 apparent second stroke end position, there is a state in which the cover insert part 46 the insert unit 63 in the outer relief structure 43 of the drive piston 24th is inserted. The insertion occurs during the drive movement 35 , with the piston insert 47 gradually into the outer relief structure 43 engages axially when the drive piston 24th approaches the second stroke end position.

If the direction of movement is reversed, the drive piston releases 24th again from the stationary on the end cover 7 , 9 fixed insert unit 63 and moves without this unit of action 63 back to the first stroke end position.

Because the stakes 63 on the drive housing 4th are fixed, is the moving mass of the drive units 22 , 23 during the drive movement 35 regardless of the measures reducing the dead space, relatively small.

In operation one with the insert parts 46 , 47 equipped double-acting rotary actuator 2nd is from the outer drive chambers 26 , 27 only that residual volume of the outer drive chamber 26 , 27 to ventilate and ventilate that after subtracting from the cover insert 46 and the piston insert 47 occupied volume remains.

From the above explanations it is clear that one and the same type of end cover 7 , 9 and drive units 22 , 23 can be used to choose a double-acting rotary actuator 2nd or a single-acting rotary actuator 3rd to realize. When manufacturing a rotary actuator 2nd , 3rd can in the opposing inner and outer relief structures 39 , 43 optionally the cover insert parts 46 and the piston insert parts 47 or a compression spring device 36 be used.

The rotary drive arrangement preferably contains 1 at least one double-acting rotary actuator 2nd and at least one single-acting rotary actuator 3rd who in the design of their end covers 7 , 9 and their drive units 22 , 23 match, being in the relief structures 39 , 43 of the double-acting rotary actuator 2nd the cover insert parts 46 and piston insert parts 47 are used while in the relief structures 39 , 43 of the single-acting rotary actuator 3rd the compression spring devices 36 intervention.

The double-acting rotary actuator is identical 2nd and the single-acting rotary drive 3rd preferably in the entire drive housing 4th and especially in the output shafts 13 .

In a configuration as a single-acting rotary drive 3rd contains the drive housing 4th expediently the same fluid channel system 33 like the double-acting rotary actuator 2nd , with only the second subchannel system 33b is not used to pass a drive fluid.

It is particularly advantageous if the rotary drive arrangement 1 at least one double-acting rotary actuator 2nd and at least one single-acting rotary actuator 3rd contains, these rotary drives 2nd , 3rd apart from the lid insert parts available in one case 46 and piston insert parts 47 and the compression spring devices present in the other case 36 are designed to match.

In connection with the double-acting rotary actuator 2nd is that from the 5 and 6 apparent second stroke end position of the two drive units 22 , 23 preferably defined by the fact that the drive piston 24th on one the inner relief structure 39 framing stop surface of the end cover 7 , 9 comes to rest from an annular surface section of the inner end face 38 is formed. Alternatively, the second stroke end position can also be achieved by contacting the piston insert 47 on the cover insert 46 be defined.

The cover insert 46 and the piston insert 47 In terms of design, they are especially matched to one another so that the second stroke end position of the drive units 22 , 23 regardless of whether the insert parts 46 , 47 are present or not, the same is.

Claims (19)

Fluid-operated rotary drive (2) of a double-acting type, with a drive housing (4) having a longitudinal axis (5), which has an end cover (7, 9) on each end face and in which two drive units (22, each having a drive piston (24) 23) are arranged axially displaceably, which are in meshing engagement with an output shaft (13) accessible from outside the drive housing (4), an inner drive chamber (25) between the two drive pistons (24) and between each drive piston (24) and the axial one opposite end cover (7, 9) a spring device-free outer drive chamber (26, 27) are formed and these drive chambers (25, 26, 27) controlled via a fluid channel system (33) of the rotary drive (2) in such a way that a drive fluid can be acted on so that the two drive units (22, 23) can be driven in opposite linear drive movements (35), from which a rotary Abtriebsbe movement (16) of the output shaft (13) results, each end cover (7, 9) on its outer drive chamber (26, 27) delimiting inner end face (38) and each drive piston (24) on its one outer drive chamber (26, 27 ) delimiting outer end face (42) has a relief structure (39, 43) having at least one axial recess (44), characterized in that in each outer drive chamber (26, 27) a relief structure (39) of the inner end face (38 ) of the end cover (7, 9) inserted or designed for insertion into this relief structure (39), cover insert part (46) and into the relief structure (43) of the outer end face (42) of the drive piston (24) inserted or for insertion into it Relief structure (43) formed piston insert part (47) are arranged. Fluid operated rotary actuator (2) after Claim 1 , characterized in that the cover insert part (46) and the piston insert part (47) arranged in the same outer drive chamber (26, 27) are combined in a single insert unit (63) in such a way that they consistently and expediently integrally connected components of the insert unit (63) form. Fluid operated rotary actuator (2) after Claim 2 , characterized in that the cover insert part (46) of the insert unit (63) is inserted into the relief structure (39) of the inner end face (38) of the end cover (7, 9) and is fastened to the end cover (7, 9), the piston insert part (47) of the insert unit (63) during the drive movement (35) of the opposite drive unit (22, 23) alternately comes into and out of engagement with the relief structure (43) of the drive piston (24), so that in a first stroke end position of the drive unit (22 , 23) is out of engagement with the relief structure (43) of the drive piston (24) and is inserted into the relief structure (43) of the drive piston (24) in a second stroke end position of the drive unit (22, 23). Fluid operated rotary actuator (2) after Claim 3 , characterized in that the cover insert (46) is non-positively and / or positively and / or cohesively fastened in the relief structure (39) of the associated end cover (7, 9). Fluid operated rotary actuator (2) after Claim 1 , characterized in that the cover insert part (46) and the piston insert part (47) arranged in the same outer drive chamber (26, 27) are designed as separate components which are not connected to one another. Fluid operated rotary actuator (2) after Claim 5 , characterized in that each cover insert part (46) is inserted into the relief structure (39) of the inner end face (38) of the associated end cover (7, 9) and is fastened to the end cover (7, 9) and that each piston insert part (47) in the relief structure (43) of the outer end face (42) of the associated drive piston (24) is inserted and fastened to the drive piston (24) so that it follows the drive movement (35) of the drive unit (22, 23). Fluid operated rotary actuator (2) after Claim 5 or 6 , characterized in that the cover insert (46) and / or the piston insert (47) is non-positively and / or positively and / or cohesively fastened in the associated relief structure (39, 43). Fluid-operated rotary drive (2) according to one of the Claims 5 to 7 , characterized in that the cover insert parts (46) and the piston insert parts (47) are flat on their mutually facing end faces (55, 56). Fluid-operated rotary drive (2) according to one of the Claims 1 to 8th , characterized in that the inner end face (38) of each end cover (7, 9) has an edge-side surface section (57) which frames the relief structure (39) and with which the cover insert part (46) inserted into the relief structure (39) is axially flush and / or that the outer end face (43) of each drive piston (24) has an edge-side surface section (62) which frames the relief structure (43) and with which the piston insert part (47) inserted into the relief structure (43) is at least essentially axially flush. Fluid-operated rotary drive (2) according to one of the Claims 1 to 9 , characterized in that each relief structure (39, 43) has a plurality of spaced-apart axial depressions (44). Fluid-operated rotary drive (2) according to one of the Claims 1 to 10th , characterized in that the at least one axial recess (44) of the relief structures (39, 43) of the end cover (7, 9) and the drive piston (24) through the cover insert part (46) inserted into the respective relief structure (39, 43) or Piston insert part (47) is completely filled. Fluid-operated rotary drive (2) according to one of the Claims 1 to 11 , characterized in that each cover insert part (46) has a shape complementary to the relief structure (39) of the end cover (7, 9) on its outer end face facing the adjacent end cover (7, 9). Fluid-operated rotary drive (2) according to one of the Claims 1 to 12th , characterized in that each piston insert part (47) has a shape complementary to the relief structure (43) of the drive piston (24) on its inner end face facing the adjacent drive piston (24). Fluid-operated rotary drive (2) according to one of the Claims 1 to 13 , characterized in that each cover insert part (46) and / or each piston insert part (47) consists of plastic material. Fluid-operated rotary drive (2) according to one of the Claims 1 to 14 , characterized in that each cover insert (46) and / or each piston insert (47) is designed as a solid material body. Fluid-operated rotary drive (2) according to one of the Claims 1 to 15 , characterized in that the drive housing (4) has a tubular middle housing part (8) in which the output shaft (13) is rotatably mounted about its longitudinal axis (12) and on each of its two end faces one of the end covers (7, 9) is mounted. Rotary drive arrangement (1), with several fluid-operated rotary drives (2, 3), among which are at least one double-acting rotary drive (2) and at least one single-acting rotary drive (3), each of which has a drive housing (4) with a longitudinal axis (5) which has an end cover (7, 9) on each end face and in which two drive units (22, 23) each having a drive piston (24) are axially displaceable, which have an output shaft (13) accessible from the outside of the drive housing (4) ) are in meshing engagement and which can be driven by means of a fluid channel system (33) of the rotary drive (2, 3) by controlled fluid application to opposite linear drive movements (35), from which a rotary output movement (16) of the output shaft (13) results, between the two drive pistons (24) an inner drive chamber (25) and between each drive piston (24) and the adjacent one n end cover (7, 9) an outer drive chamber (26, 27) are formed, each end cover (7, 9) on its an outer drive chamber (26, 27) delimiting inner end face (38) and each drive piston (24) on it an outer drive surface (42) delimiting an outer drive chamber (26) has a relief structure (39, 43) having at least one axial recess (44), one in each case in the outer drive chambers (26, 27) of the single-acting rotary drive (3) compression spring device (36) supporting the end cover (7, 9) and the drive piston (24) is arranged, while the outer drive chambers (26, 27) of the double-acting rotary drive (2) contain no spring device, the single-acting rotary drive (3) and the double-acting rotary drive (2) is identical to one another both in terms of its end cover (7, 9) and in terms of its drive units (22, 23), dad characterized in that in each outer drive chamber (26, 27) of the double-acting rotary drive (2) one inserted into the relief structure (39) of the inner end face (38) of the end cover (7, 9) or for insertion into this relief structure (43) formed cover insert part (46) and a piston insert part (47) inserted into the relief structure (43) of the outer end face (42) of the drive piston (24) or designed for insertion into this relief structure (43). Rotary drive arrangement (1) after Claim 17 , characterized in that the single-acting rotary drive (3) and the double-acting rotary drive (2) have an identical drive housing (4). Rotary drive arrangement (1) after Claim 17 or 18th , characterized in that the double-acting rotary drive (2) according to the characterizing part of one of the Claims 2 to 16 is trained.

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