Fluid-operated rotary drive device

Abstract

Rotary drive device (1), comprising a drive housing (2) in which at least one elongated receiving space (15a, 15b) is formed with a longitudinal axis (16a, 16b) parallel to a main axis (6) of the drive housing (2), in which a drive unit (24a, 24b) is received that can be linearly displaced back and forth by controlled fluid application while performing a drive movement (29), which has a longitudinal axis (30) parallel to the longitudinal axis (16a, 16b) of the receiving space (15a, 15b) and which has a rack-like drive toothing (28) on an inner longitudinal side (39), which engages in gearing with the output toothing ring (48) of an output unit (38) rotatable about a rotation axis (5) perpendicular to the main axis (3) relative to the drive housing (2) inside the drive housing (2), such that the linear The drive movement (29) of the drive unit (24a, 24b) results in a rotary output movement (43) of the output unit (38), wherein the drive unit (24a,24b) in the region of its outer longitudinal side (55) opposite the drive gear (28) by means of a guide device (56) separate with respect to the drive unit (24a, 24b) on a circumferential wall section (40) of the drive housing (2) peripherally bounding the receiving space (15a, 15b), wherein the guide device (56) is combined with the drive unit (24a, 24b) to form an assembly such that it participates in its drive movement (29), and wherein the guide device (56) has at least one guide element (57) attached to the drive unit (24a, 24b), which has at least one guide surface (58a, 58b) on its radial outer side facing away from the drive unit (24a, 24b), with which it slides slidably on the inner circumferential surface (41) of the section of the wall peripherally bounding the receiving space (15a, 15b). circumferential wall section (40) of the drive housing (2), characterized in that the guide element (57) is located in a drive unit (24a,24b) is arranged in a partially enclosing manner on the longitudinal section of the drive unit (24a, 24b) occupied by the drive gear (28), with a recess for the drive gear (28).

Description

[0001] The invention relates to a fluid-actuated rotary drive device with a drive housing in which at least one elongated receiving space is formed with a longitudinal axis parallel to a main axis of the drive housing, in which a drive unit is received that can be linearly displaced back and forth by controlled fluid application while performing a drive movement, which has a longitudinal axis parallel to the longitudinal axis of the receiving space and which has a rack-like drive toothing on an inner longitudinal side, which engages in toothing with the output toothing ring of an output unit rotatable about an axis of rotation perpendicular to the main axis relative to the drive housing inside the drive housing, so that a rotary output movement of the output unit results from the linear drive movement of the drive unit.wherein the drive unit is supported in the area of ​​its outer longitudinal side opposite the drive gearing by means of a guide device separate from the drive unit on a circumferential wall section of the drive housing that peripherally delimits the receiving space, wherein the guide device is combined with the drive unit to form an assembly such that it follows its drive movement, and wherein the guide device has at least one guide element attached to the drive unit, which has at least one guide surface on its radial outer side facing away from the drive unit, with which it slides against the inner circumferential surface of the circumferential wall section of the drive housing that peripherally delimits the receiving space.

[0002] A fluid-actuated rotary drive device of this type, known from EP 2 495 450 A1, has a drive housing in which two elongated receiving spaces are arranged side by side. Each of these spaces holds a linearly displaceable drive unit, which has a rack-like drive toothing on its inner side that meshes with a rotatable output unit. Each drive unit is equipped with a guide device by which it is radially supported on a circumferential wall section of the drive housing in a displaceable manner. The guide device consists of two annular guide elements, each axially adjacent to a sealing ring and located axially next to the drive toothing on two end head sections of the drive units.

[0003] A lifting and swiveling unit known from DE 20 2005 000 049 U1 has two linearly displaceable rack pistons which engage with a gear and which are equipped with a radially projecting cylindrical pin to prevent rotation, which slides into a groove and is laterally guided therein.

[0004] DE 20 2004 003 694 U1, DE 11 2011 103 042 T5 and GB 2 128 682 A each describe a rotary drive with two linearly movable drive units that are axially sequentially mounted in a receiving space of a drive housing and axially overlap with two racks that mesh with a rotaryally driven gear. Each rack projects freely from a piston of the drive unit and is equipped at a distance from the piston with a sliding shoe that bears radially against a circumferential wall section of the drive housing in a slidingly displaceable manner.

[0005] From EP 0 089 568 A1, a pressure-medium-operated rotary drive device is known, comprising two drive units, each with a piston and a rack section projecting axially from the piston. The rack section has a base body formed integrally with the piston and a separate rack attached to the base body.

[0006] EP 2 093 432 B1 describes a rotary actuator comprising two drive units arranged side by side in a drive housing, each with two piston sections and a rack extending between them. Each rack carries a magnet used for position detection.

[0007] A fluid-operated rotary drive device known from US 4,970,944 has a drive housing in which two drive units are arranged to be linearly displaceable. Each drive unit has a rack-like drive toothing on an inner longitudinal side, which meshes with the output toothing of an output unit arranged and rotatably mounted between the two drive units. The two drive units can be driven by a controlled fluid supply to a reciprocating drive motion, resulting in a rotary output motion of the output unit that can be accessed outside the drive housing. Each drive unit has a drive piston with a sealing ring and a rack section projecting axially from the drive piston, which has the drive toothing.A guide ring is mounted coaxially on the drive piston, sliding against a circumferential wall section of the drive housing that peripherally defines the receiving chamber. Additionally, each rack section is associated with a guide device attached to the drive housing, against which the rack section, with its outer surface opposite the drive teeth, slides. The guide device consists of an arcuate bearing element that is inserted into a recess in the circumferential wall section of the drive housing that defines the receiving chamber.

[0008] DE 10 2015 114 363 A1 describes a rotary drive device with two receiving spaces formed in a drive housing, in each of which a drive unit is arranged to be linearly displaceable and has a drive toothing on an inner longitudinal side. A rotatably mounted output unit extends between the two drive units and has an output toothing ring that meshes with the two drive toothings. Each drive unit has a drive piston with a sealing ring and a guide ring at both axial end regions, wherein both the sealing ring and the guide ring are slidably in contact with a circumferential wall section of the drive housing that encloses the associated receiving space. The drive units receive no additional support in the longitudinal section occupied by the drive toothing.

[0009] The invention is based on the objective of creating a fluid-operated rotary drive device that can be realized with compact dimensions and at low cost.

[0010] To solve this problem, the invention provides that the guide element is arranged on the longitudinal section of the drive unit occupied by the drive teeth in a manner that only partially encloses the drive unit, leaving a recess for the drive teeth.

[0011] The fluid-actuated rotary drive device according to the invention has at least one drive unit which, on an inner longitudinal side, has a rack-like drive toothing that engages with the output gear ring of a rotatable output unit, and which, in the region of its outer longitudinal side diametrically opposite the drive toothing, is equipped with a guide device by means of which it is slidably supported on the inner circumferential surface of a circumferential wall section of the drive housing that peripherally delimits the receiving space. The drive unit and guide device are combined into a single assembly so that they always execute the drive movement as a single unit. During operation of the rotary drive device, the drive unit is subjected to often high lateral forces by the described toothing engagement in the region of the output unit, which push the drive unit outwards away from the output unit.These lateral forces are introduced into the drive housing via the guide device, providing reliable lateral support for the drive unit. This ensures secure gear engagement and enables the transmission of high torques. The guide device consists of at least one guide element mounted on the drive unit along the length of the drive gear, i.e., directly where the highest lateral forces occur during operation. This guide element can extend over only a portion or the entire axial length of the drive gear. Preferably, the guide device does not extend beyond the axial length of the drive gear, allowing the drive unit to be built with relatively compact dimensions without compromising its support.Since the drive unit requires no support on the side of the drive gear, the guide device extends only partially around the drive unit, leaving the drive gear exposed. Additional guide rings, which would extend axially around the drive unit in a region adjoining the drive gear and thus lengthen the drive unit, are unnecessary. The guide device can comprise several axially spaced guide elements, but preferably consists of only a single guide element.

[0012] The drive gearing in each drive unit has a multitude of teeth that are arranged consecutively in the longitudinal direction of the drive unit and each extends transversely to this longitudinal direction.

[0013] Advantageous further developments of the invention are set out in the dependent claims.

[0014] Particularly for applications requiring only low torque from the output unit, the rotary drive device can be equipped with just a single drive unit. However, it is generally considered advantageous for the rotary drive device to have two drive units, which, if necessary, can generate a higher combined torque and, in any case, ensure symmetrical and therefore particularly gentle force transmission to the output gear ring. In this context, it is advantageous if two drive units, arranged side by side in parallel longitudinal alignment and each combined into a single assembly with a guide device, are linearly displaceable within the drive housing. The output unit is located between the two drive units, whose drive gears face each other and both are in mesh with the output gear ring.The engagement areas are diametrically opposed to each other with respect to the axis of rotation of the output unit, thus ensuring symmetrical force transmission. In principle, both drive units can be arranged in a common mounting space; however, it is considered particularly advantageous if each drive unit is housed in its own separate mounting space.

[0015] The at least one guide element of the guide device is preferably formed in one piece and made of a plastic material. This guide element is preferably an injection-molded part that can be manufactured cost-effectively.

[0016] The guide element is preferably designed to be axially shorter than the rack-like drive teeth of the associated drive unit, and is axially extended beyond these drive teeth on both sides. Reliable lateral support of the drive unit is also possible if the at least one guide element extends only over a portion of the drive teeth.

[0017] As already mentioned, it is considered advantageous to design the guide system with only a single guide element. This guide element can be manufactured very easily with the desired axial length. A single guide element is also easier to mount than several separate guide elements. Nevertheless, it is in principle possible to design the guide system with several independent guide elements, each individually fixed to the drive unit.

[0018] The guide device can optionally have only a single guide surface or several guide surfaces spaced apart from each other in the longitudinal direction of the drive unit. Multiple guide surfaces can be distributed across several guide elements or formed at axial intervals on one and the same guide element.

[0019] It is advantageous if the at least one guide surface has an arcuate curvature corresponding to the curvature of the inner circumferential surface of the circumferential wall section of the drive housing that defines the receiving space. This is particularly a circular arc curvature. The length of the guide surface, measured in the circumferential direction of the receiving space, expediently corresponds to an arc angle of approximately 180 degrees. Preferably, the arc angle is substantially or exactly 180 degrees. This ensures very reliable sliding guidance for the drive unit, even though it is not supported peripherally all around. Generally, an angular extent with an arc angle between 150 and 185 degrees (inclusive) is considered particularly advantageous.

[0020] Preferably, the at least one guide element is designed in a shell-like shape, with a groove-like mounting recess on its radially inner side facing the drive unit. This recess allows the guide element to be mounted onto the drive unit from the radial outside in a rider-like manner. The drive unit partially engages in the mounting recess. This design allows the at least one guide surface to extend over a relatively large arc angle around the drive unit without adversely affecting the transverse dimensions of the assembly consisting of the drive unit and the guide element, as measured in the radial direction of the output unit's axis of rotation.

[0021] The at least one guide element can be attached to the drive unit in any desired manner. For example, a screw connection or an adhesive connection can be used. A plug connection, implemented by means of a plug-in connector, is considered particularly advantageous. The plug-in connector is designed such that the connection can be established by a plugging operation that is radial to the longitudinal axis of the drive unit. The plug-in connector can be designed such that the interlocking of the inserted parts is achieved by compression and / or by locking.

[0022] In a particularly advantageous embodiment of the plug connection device, the guide element has at least one radially inwardly projecting mounting pin on its radial inner side facing the drive unit. This mounting pin is inserted into and held in a mounting hole formed in the drive unit. The mounting pin is held in the mounting hole, for example, by frictional locking, positive locking, or a combination of both.

[0023] In a particularly advantageous design of the plug connection device, only a single pair of mounting pins and mounting holes is present, which is located in particular in the axial center of the guide element in question.

[0024] The guide element advantageously has an elongated shape and is fixed to the drive unit such that its longitudinal axis runs parallel to the longitudinal axis of the drive unit. On its outer surface, the guide element advantageously has several narrow, strip-shaped guide surfaces arranged axially apart from one another, each extending in an arc a short distance around the longitudinal axis of the guide element. It is considered advantageous if the guide element has exactly two such strip-shaped guide surfaces.

[0025] Preferably, the guide element has exactly two guide surfaces, each arranged on one of the two axial end sections of the guide element, wherein the guide element has a connecting section extending between the two axial end sections, which does not come into contact with the circumferential wall section of the drive housing, so that a guide contact between the guide element and the drive housing exists exclusively in the area of ​​the two guide surfaces.

[0026] Alternatively, the guide element could, for example, be provided with a continuous guide surface extending over the entire axial length of the guide element.

[0027] It is advantageous if, during operation of the rotary drive device, it is possible to detect the position of at least one drive unit, from which conclusions can be drawn about the rotational position of the output unit. Such position detection is preferably carried out by means of a permanent magnet attached to at least one drive unit, which interacts contactlessly with a position sensor device mounted externally on the drive housing. In connection with the rotary drive device according to the invention, it is advantageous if such a permanent magnet is fixed in a guide element of the guide device. The guide element can then be fitted with the permanent magnet before its mounting on the drive unit. No measures are required on the drive unit itself to enable the attachment of a permanent magnet.Because the permanent magnet is located within the guide element, its magnetic field is not adversely affected by the drive unit, even if the drive unit is made entirely or partially of a ferromagnetic material. Therefore, the drive unit, and especially the rack section containing the rack-like drive teeth, can be made entirely or partially of a cost-effective ferromagnetic steel. The use of expensive stainless steel is unnecessary. However, the rack section can, in principle, be made of any material that possesses the required strength.

[0028] To secure the permanent magnet, the guide element advantageously includes a receiving pocket open radially outwards towards the circumferential wall section of the drive housing, into which the permanent magnet is inserted. The permanent magnet is, for example, pressed in, glued in, and / or snapped or clipped into place. The receiving pocket is preferably located in a region of the guide element situated between two axially spaced guide surfaces.

[0029] A particularly advantageous placement for the mounting pocket is found in connection with a plug-in connection device having a mounting pin, in an area where a mounting pin is located. Since the mounting pin projects into a mounting hole of the drive unit, there is no material from the drive unit in this area that could interfere with the magnetic field of the permanent magnet. Preferably, the mounting pin and the mounted permanent magnet are positioned one behind the other on a line extending radially with respect to the longitudinal axis of the drive unit.

[0030] The controlled fluid supply to a respective drive unit can be facilitated by the drive unit having at least one drive piston with a rubber-elastic sealing ring that slides and seals against the inner circumferential surface of the peripheral wall section of the drive housing that defines the receiving space. In this way, the drive piston forms a movable boundary wall of a drive chamber located within the receiving space, into which a fluid channel opens. This channel allows the supply or discharge of a fluidic pressure medium that provides the driving force and acts as the drive fluid. A section extending axially from the drive piston features the rack-like drive teeth and can therefore be referred to as the rack section.

[0031] To implement a single-acting rotary drive device, each drive unit can be equipped with only a single drive piston. Preferably, two single-acting drive units are provided to generate a reciprocating output motion, which can be alternately pressurized with a fluidic pressure medium. Alternatively, only a single single-acting drive unit can be provided, in which the return stroke is effected by spring force, for example, by means of a mechanical spring or an air spring.

[0032] Particularly for generating high torques, it is advantageous if at least one drive unit is designed for double-acting fluidic actuation. In this case, the drive unit has two axially spaced drive pistons, each defining one of two fluid-filled drive chambers within the receiving space and connected to each other by a rack section featuring the rack-like drive teeth. Preferably, the rack section and the drive pistons are fixedly attached to one another. This can be a one-piece design or a multi-part design whose components are fixed to one another by fasteners.

[0033] It is considered particularly advantageous if the rack section of the drive unit is a separate rack body for each drive piston, to which each drive piston is fixed by means of a fastening device. For example, the drive piston is pressed firmly into the end face of the rack body. A multi-part design of the drive unit allows for a modular construction, enabling the production of single-acting or double-acting rotary drive devices as required.

[0034] The drive teeth preferably extend over the entire axial length of the rack body, so that the two drive pistons attached to the rack body each connect directly axially to the drive teeth.

[0035] A separate rack body of the drive unit is preferably designed as a square bar with a rectangular cross-sectional profile, which has the drive teeth on one of its four longitudinal sides.

[0036] As already mentioned at the outset, it is advantageous if each drive piston of the drive unit is designed without a guide ring, meaning it does not have its own guide ring that is in sliding contact with the inner circumferential surface of the wall that defines the drive chamber. The only component of the drive piston in contact with this wall is a sealing element of the sealing ring, preferably a sealing lip.

[0037] If the drive piston lacks a guide ring, it can be made very short axially, and the saved length can be used for the drive gearing. This allows a very large proportion of the drive unit's length to be dedicated to the drive gearing. Consequently, the entire rotary drive device can be designed with a very short overall length. Furthermore, it is possible to achieve a relatively large output gear diameter despite maintaining compact dimensions, particularly when generating very high torques.

[0038] The rotary drive device can be equipped with an adjustable stroke preselection device, which allows the maximum possible stroke of the at least one drive unit to be preselection, thereby indirectly preselection of the rotation angle of the rotary output movement.

[0039] Furthermore, it is advantageous if the rotary drive device is equipped with an end-position damping device that ensures that the at least one drive unit moves into the lifting end position in a damped manner, thus avoiding high structural stresses.

[0040] The invention will now be explained in more detail with reference to the accompanying drawing. This drawing shows: Fig. 1 a preferred embodiment of the rotary drive device according to the invention in a perspective view, Fig. 2 a longitudinal section of the rotary drive device Fig. 1 in a plane perpendicular to the axis of rotation of the output unit according to section line II-II from Fig. 3, Fig. 3 a cross-section through the rotary drive device in the area of ​​the axis of rotation of the output unit and according to section line III-III from Fig. 2, Fig. 4. A perspective view of one of the drive units of the rotary drive device. Fig. 5 a single representation of a sub-assembly consisting of a rack body, a guide element and a permanent magnet of one of the drive units of the rotary drive device, and Fig. 6 the sub-assembly from Fig. 5 in a perspective exploded view.

[0041] The rotary drive device, designated in its entirety by reference numeral 1, is designed for actuation by means of fluid force and can be driven by a fluidic pressure medium. Preferably, the rotary drive device is designed for operation with compressed air as the fluidic pressure medium, so that it can be referred to as a pneumatic rotary drive device.

[0042] The rotary drive device 1 has a preferably elongated housing, made in particular of metal, which is referred to as the drive housing 2. The drive housing 2 extends along an imaginary main axis 3, indicated by a dashed line, which expediently also forms a central longitudinal axis of the drive housing 2. In the Fig. The main axis 3 runs perpendicular to the drawing plane.

[0043] The drive housing 2 also has a transverse axis 4 perpendicular to the main axis 3 and a vertical axis 5 perpendicular to both the main axis 3 and the transverse axis 4. The main axis 3 and the transverse axis 4 together span an imaginary plane designated as the main plane 6. The section plane of the longitudinal section according to Fig. 2 is located in this main level 6.

[0044] The drive housing 2 has several outer surfaces on its exterior. In particular, it has a first outer surface 7 oriented in the axial direction of the vertical axis 5 and a second outer surface 8 oriented in the opposite direction. In the illustrated embodiment, the first outer surface 7 is located on a top side and the second outer surface on a bottom side of the drive housing 2.

[0045] The drive housing advantageously has an elongated cross-section perpendicular to the main axis 3. This is preferably a substantially rectangular cross-section, the longer sides of which are defined by the first and second outer housing surfaces 7, 8. The narrow sides of the cross-section are oriented in the axial direction of the transverse axis 4 and, in the exemplary embodiment, are formed by two opposing lateral outer housing surfaces 12, 13 of the drive housing 2.

[0046] Advantageously, at least one mounting groove 14 extending in the axial direction of the main axis 3 is formed in one or both of the outer lateral housing surfaces 12, 13, in which additional components can be fixed. At least one mounting groove 14 on only one, and preferably on both, outer lateral housing surfaces 12, 13 serves, by way of example, to fix a position sensor device 11, indicated only by dashed lines, the function of which will be discussed in more detail below. The position sensor device 11 contains one or more position sensors and / or is designed as a displacement measuring system.

[0047] Inside the drive housing 2, two first and second receiving spaces 15a, 15b, each with a longitudinal extension, are formed. These receiving spaces extend parallel to each other and each has a longitudinal axis 16a, 16b, which runs parallel to the main axis 3.

[0048] The two receiving chambers 15a, 15b are arranged side by side at a distance along the axis of the transverse axis 4 and separated from each other by a partition wall 17 extending between them. Preferably, the longitudinal axes 16a, 16b of the two drive chambers 15a, 15b lie in the main plane 6.

[0049] Each receiving chamber 15a, 15b expediently has a round and preferably a circular cross-section. The receiving chambers 15a, 15b are thus cylindrical and preferably circular-cylindrical in shape.

[0050] In the preferred embodiment, the drive housing 2 comprises a one-piece main body 18 containing the two receiving spaces 15a, 15b along their entire length, and two housing covers 21 attached to the main body 18, each closing one of the two receiving spaces 15a, 15b at an end face. The drive housing 2 has two front and rear end faces 22, 23 oriented in the axial direction of the main axis 3 and oppositely oriented to each other. The receiving spaces 15a, 15b are bounded in the region of the front end face 22 by an integral front end wall 22a of the main body 18 and in the region of the rear end face 23 by the housing covers 21 attached to the main body 18. The housing covers 21 are expediently inserted into the main body 18 with a seal and secured to the main body 18 by retaining rings 20.

[0051] In each receiving chamber 15a, 15b, one of two drive units 24a, 24b is arranged to be linearly displaceable back and forth along the axis of the associated longitudinal axis 16a, 16b. For better differentiation, these two drive units 24a, 24b are hereinafter also referred to as the first drive unit 24a and the second drive unit 24b. The linear movement of the two drive units 24a, 24b can be brought about by controlled fluid application using the fluidic pressure medium already mentioned above and is hereinafter also referred to as the drive movement 29, which in Fig. 2 is indicated by a double arrow.

[0052] Each drive unit 24a, 24b has a longitudinal axis 30 which is aligned parallel to the longitudinal axis 16a, 16b of the receiving space 15a, 15b and which preferably runs coaxially to the longitudinal axis 16a, 16b in question.

[0053] Each drive unit 24a, 24b expediently has two first and second drive pistons 25, 26 arranged at a distance from each other in the axial direction of the longitudinal axis 30, which are rigidly connected to each other via an elongated rack section 27 extending between them. On the inner longitudinal sides 39 of the drive units 24a, 24b facing each other in the axial direction of the transverse axis 4, each rack section 27 has a rack-like drive toothing 28 which extends linearly in the axial direction of the longitudinal axis 30.

[0054] Each drive tooth 28 advantageously consists of a plurality of teeth arranged in a common plane and successively in the axial direction of the longitudinal axis 30, each extending transversely and, in particular, perpendicularly to said longitudinal axis 30. Preferably, a plane containing the teeth of a respective drive tooth 28 extends perpendicularly to the main plane 6.

[0055] Advantageously, the drive gear 28 is a one-piece, integral part of the rack section 27; however, it can be formed in a separate component fixed by fastening means.

[0056] Each drive piston 25, 26 has at least one sealing ring 32 coaxial with the longitudinal axis 30 in the region of its radial outer circumference, which is made of a material with rubber-elastic properties and in particular of an elastomer material. Preferably, each drive piston 25, 26 has a piston body 25a, 26a made of a rigid material and in particular of a plastic material, to which the associated sealing ring 32 is attached, in particular in an annular fastening groove formed on the radial outer circumference of the piston body 25a, 26a.

[0057] Each receiving chamber 15a, 15b is peripherally bounded, i.e., at its radial outer circumference, by a circumferential wall section 40 of the drive housing 2 and, in particular, of the main housing body 18. Each circumferential wall section 40 has an inner circumferential surface 41 shaped according to the inner circumferential surface of a hollow cylinder, by which the respective receiving chamber 15a, 15b is directly bounded radially on the outside. Each drive piston 25, 26 rests with its sealing ring 32 in a slidingly displaceable manner against the inner circumferential surface 41 of the circumferential wall section 40, thus providing a seal.

[0058] Each receiving chamber 15a, 15b is subdivided into a first drive chamber 33 and a second drive chamber 34 by the two drive pistons 25, 26 of the associated drive unit 24a, 24b. The first drive chamber 33 is formed by that longitudinal section of the receiving chamber 15a, 15b which extends between the first drive piston 25 and the axially opposite housing cover 21, which is associated with the rear end face 23. The second drive chamber 34 lies between the second drive piston 26 and the axially opposite front end face 22 of the drive housing 2, which is associated with the front end face 22 and is, by way of example, an integral part of the main housing body 18.

[0059] The longitudinal section of the receiving chamber 15a, 15b, located axially between the two drive pistons 25, 26 and moving axially during the drive movement 29, is advantageously pressureless and connected to the atmosphere. It is fluid-tightly separated from the two volume-varying drive chambers 33, 34 by the drive pistons 25, 26.

[0060] The drive chambers 33, 34 communicate with two connection openings 36a, 36b, which open onto the outer surface of the drive housing 2, via an internal fluid channel system 35 (indicated only by dashed lines). These connection openings 36a, 36b are connected to a pressure source supplying the fluidic pressure medium and to a pressure sink via fluid lines (not shown) and a control valve assembly (also not illustrated) to operate the rotary drive device 1. By actuating the control valve assembly accordingly, the working chambers 33, 34 can be supplied with fluid or depressurized in such a coordinated manner that the two drive units 24a, 24b simultaneously execute opposing drive movements 29.

[0061] The fluid channel system 35 is designed in particular such that one connection opening 36a is connected to the first drive chamber 33 of the first receiving space 15a and to the second drive chamber 34 of the second receiving space 15b, while the other connection opening 36b is connected to the second drive chamber 34 of the first receiving space 15a and to the first drive chamber 33 of the second receiving space 15b.

[0062] In this way, the two drive units 24a, 24b can be actuated fluidically in a double-acting manner, such that each drive unit 24a, 24b can be displaced in both directions of its drive movement 29 by means of fluid force.

[0063] The linear drive movements 29 of the two drive units 24a, 24b are converted into a rotary output movement 43, indicated by a double arrow, of an output unit 38, which also belongs to the rotary drive device 1. The direction of rotation of the output movement 43 depends on the direction of movement of the drive movements 29. By driving the drive units 24a, 24b in a reciprocating drive movement, an oscillating rotary movement can be obtained from the output unit 38 as the output movement 43.

[0064] For the conversion of the linear drive motion 29 into the rotary output motion 43, each drive unit 24a, 24b with its rack-like drive teeth 28 engages with a ring-shaped, self-contained output gear 48. This gear engagement defines a gear transmission.

[0065] The output unit 38 is mounted on the drive housing 2 such that it is rotatable about a pivot axis 45 relative to the drive housing 2 to execute the output movement 43. For this purpose, two rotary bearing assemblies 44a, 44b are provided, spaced apart from each other in the axial direction of the pivot axis 45, and are preferably designed as rolling bearing assemblies. The rotary bearing is designed such that the pivot axis 45 is perpendicular to the main axis 3 and, in particular, also perpendicular to the transverse axis 4. Preferably, the pivot axis 45 extends perpendicular to the main plane 6.

[0066] The axis of rotation 5 runs between the two drive units 24a, 24b in the area of ​​the drive teeth 28. The output gear 48 is located at the same height in the axial direction of the axis of rotation 45 as the two drive teeth 28, which are opposite each other in the axial direction of the transverse axis 4 and spaced apart. The diameter of the output gear 48 is selected such that it engages with the drive teeth 28 of both drive units 24a, 24b simultaneously.

[0067] The output gear ring 48 is arranged radially on the outside of an output shaft 47 of the output unit 38 and extends all around the output shaft 47. Preferably, the output gear ring 48 is designed in the manner of a gear or pinion. The output gear ring 48 particularly has spur teeth, wherein the teeth of the output gear ring 48 are each aligned parallel to the axis of rotation 45.

[0068] Preferably, the output gear ring 48 is integrally connected to the output shaft 47, as is the case in the exemplary embodiment. However, the output gear ring 48 can also be attached to the output shaft 47 as a separate output gear.

[0069] The longitudinal direction of the output shaft 47 defines a longitudinal axis 37 of the output unit 38, which forms the axis of rotation 45.

[0070] The output gear ring 48 is advantageously located axially between the two rotary bearing assemblies 44a, 44b. The same applies to the two receiving spaces 15a, 15b and drive units 24a, 24b.

[0071] The output unit 38 has a tap section 49 accessible outside the drive housing 2, from which the rotary output motion 43 can be tapped to drive any external component. The tap section 49, which is exemplarily designed as a disc, has at least one mounting interface 49a via which a component to be driven rotary can be detachably attached to the tap section 49. The mounting interface 49a consists, for example, of several mounting holes. The disc-shaped tap section 49 is arranged coaxially to the longitudinal axis 37 at an end region of the output shaft 47 and is preferably formed integrally with this output shaft 47.

[0072] The gear meshing between the output gear ring 48 and the two drive gears 28 takes place within the two receiving spaces 15a, 15b. Each of the two circumferential wall sections 40 has a window-like recess 52 in the area of ​​the intermediate wall 17, through which the output gear ring 48 projects laterally into the respective receiving space 15a, 15b with a circumferential section. The window-like recesses 52 belong to a recess 54 that penetrates the intermediate wall 17, in which the output unit 38 extends.

[0073] In contrast to the illustrated embodiment, of the two parallel receiving spaces 15a, 15b, only one can be equipped with a drive unit 24a or 24b. In this case, the output unit 38 is driven by only a single drive unit 24a or 24b. The other receiving space can then remain empty or be used for other purposes.

[0074] A rotary drive device 1 equipped with only a single drive unit can also be designed such that its drive housing 2 has only a single receiving space.

[0075] In an embodiment of the rotary drive device 1 that is not illustrated, the at least one drive unit 24a, 24b has only a single drive piston 25 or 26. In this way, a cost-effective, single-acting design of the rotary drive device 1 can be realized.

[0076] Each drive unit 24a, 24b is slidably supported on the circumferential wall section 40 of the drive housing 2, which defines the receiving space 15a, 15b, by means of a guide device 56 separate from the associated drive unit 24a, 24b, in the region of its outer longitudinal side 55 diametrically opposite the drive teeth 28. This support, which is primarily in the axial direction of the transverse axis 4, ensures reliable gear engagement between the output gear 48 and the drive teeth 28, even when high torques are to be transmitted. Furthermore, the guide device 56 ensures smooth drive movement 29 while minimizing wear on the additional sealing rings 32.

[0077] A special feature of the guide device 56 is that it is attached to the associated drive unit 24a, 24b, so that the drive unit 24a, 24b and the guide device 56 fixed to it form a single assembly that can only be moved as a unit, with the guide device 56 always directly participating in the drive movement 29 of the drive unit 24a, 24b.

[0078] The guide device 56 has at least one rigid guide element 57 attached to the drive unit 24a, 24b, on which at least one guide surface 58a, 58b is formed, which slides against the inner circumferential surface 41 of the circumferential wall section 40 of the drive housing 2. During the drive movement 29, the guide element 57 slides along the inner circumferential surface 41 with each guide surface 58 formed on it. The contact area between the at least one guide surface 58 and the inner circumferential surface 41 is located at least in a region that is diametrically opposite to the drive gear 28 in the transverse direction 6.

[0079] A special feature of the at least one guide element 57 is that it is located in the longitudinal section of the drive unit 24a, 24b occupied by the drive teeth 28 and extends only partially around the drive unit 24a, 24b in the circumferential direction of the longitudinal axis 30, so that at least the drive teeth 28 are not covered by the guide element 57. The at least one guide element 57 therefore has a gap, at least in the area of ​​the drive teeth 28, which still allows the unimpeded interaction of the output gear 48 with the drive teeth 28.

[0080] Apart from the at least one guide element 57, the guide device 56 expediently has no further components that perform a guiding function. In particular, none of the drive units 24a, 24b has a guide ring coaxial with the longitudinal axis 30 that extends circumferentially around the drive unit 24a, 24b. Each drive piston 25, 26 is also designed without a guide ring and has only the rubber-elastic sealing ring 32, with which it is in contact with the drive housing 2. Due to its flexibility, however, the sealing ring 32 does not perform a guiding or supporting function in the radial direction with respect to the longitudinal axis 30. This function is performed exclusively by the at least one guide element 57 of the guide device 56.

[0081] The axial direction of the longitudinal axis 30 of the drive unit 24a, 24b is hereinafter also referred to as the longitudinal direction 30 of the drive unit 24a, 24b. The guide device 56 can, in principle, have several separate guide elements 57, which are successively and, in particular, independently of one another, attached to the drive unit 24a, 24b in the aforementioned longitudinal direction 30. However, it is considered more advantageous if the guide device 56 consists of only a single guide element 57, which is the case in the illustrated embodiment. The following description is based on this embodiment.

[0082] The guide element 57 is advantageously designed as a single piece and made of a plastic material. For example, it consists of a polyamide plastic. Such a guide element 57 can be manufactured cost-effectively as an injection-molded part.

[0083] Preferably, the guide device 56, and thus by way of example the single guide element 57, is axially shorter than the rack-like drive teeth 28 of the associated drive unit 24a, 24b. The guide element 57 is positioned such that it is axially projected beyond the drive teeth 28 on both sides in the longitudinal direction 30. Preferably, the guide element 57 is positioned such that the axial projection of the drive teeth 28 is the same on both sides. In other words, the guide element 57 is preferably mounted axially centered with respect to the drive teeth 28.

[0084] Even if the guide device 56 does not extend over the entire axial length of the drive gear 28, reliable guidance and lateral support can be ensured.

[0085] The axial length of the drive gear 28 covered by the guide element 57 is advantageously greater than the sum of the lengths of the two end sections of the drive gear 28 projecting axially beyond the guide element 57.

[0086] The guide element 57 expediently has an elongated shape and has a longitudinal axis 62 which, when mounted on the drive unit 24a, 24b, runs parallel to the longitudinal axis 30 of the drive unit 24a, 24b.

[0087] The at least one guide surface 58 is advantageously curved with the same curvature as the inner circumferential surface 41 of the circumferential wall section 40 with which it is in contact. Accordingly, the guide surface 58 is convex.

[0088] Since the drive gear 28 is recessed from the guide surface 58a, 58b, the guide surface 58a, 58b extends along an arc angle around the longitudinal axis 30 of the drive unit 24a, 24b, which is less than 360 degrees. For example, the arc length is approximately 180 degrees.

[0089] The guide surface 58 is positioned such that it is divided by the main axis 6 into two arc segments of equal length, one located on this side and the other on the other side of the main plane 6. The vertex of the curved guide surface 58 is advantageously located in the main plane 6.

[0090] According to an embodiment not illustrated, the guide element 57 has only a single guide surface which is continuous in the axial direction of the longitudinal axis 62 and extends in particular over the entire axial length of the guide element 57.

[0091] A particularly precisely defined guide with optimal guiding and supporting contact between the guide element 57 and the inner circumferential surface 41 is achieved when the guide element 57 has exactly two guide surfaces 58a, 58b, which are arranged at a distance from each other in the axial direction of the longitudinal axis 62 and each extend in a strip-like shape in the circumferential direction of the longitudinal axis 30. Each strip-shaped guide surface 58a, 58b is curved in an arc-like shape in its longitudinal direction.

[0092] Each guide element 57 has two axial end sections 63, 64 opposite each other in the axial direction of its longitudinal axis 62, and it is advantageous if the two guide surfaces 58a, 58b are each arranged on one of these two axial end sections 63, 64. Preferably, each guide surface 58 extends to the axial end face 68 of the associated axial end section 63, 64 of the guide element 57.

[0093] The guide element 57 rests exclusively on the inner circumferential surface 41 of the circumferential wall section 40 with its two guide surfaces 58a, 58b. A connecting section 65 extending between them, which connects the two axial end sections 63, 64, is continuously spaced from the circumferential wall section 40. This prevents over-constraints.

[0094] According to a particularly advantageous design, which is implemented in the exemplary embodiment, the guide element 57 is shell-shaped. It has a radial outer surface or a radial outer circumferential region 87, on which the at least one guide surface 58a, 58b is located, and it has a correspondingly opposite radial inner surface 66, which is recessed in a channel-like manner and has a groove-like mounting recess 67 extending in the axial direction of the longitudinal axis 62. This mounting recess 67 is axially continuous and opens onto the two opposing axial end faces 68 of the guide element 57.

[0095] The guide element 57 is placed radially onto the drive unit 24a, 24b with its radial inner side 66 facing forward in the region of the outer longitudinal side 55, so that the drive unit 24a, 24b partially engages in the mounting recess 67. In other words, the cup-shaped guide element 57 is mounted onto the drive unit 24a, 24b in a rider-like manner from the outer longitudinal side 55.

[0096] The groove-like mounting recess 67 has a slot-like recess opening 67a arranged on the radial inner side 66, a recess base surface 67b opposite this recess opening 67a, and two recess flanks 67c opposite each other, each extending between the recess opening 67a and the recess base surface 67b. Both the recess base surface 67b and the recess flanks 67c can be completely closed or partially perforated, the latter being the case in the illustrated embodiment.

[0097] The cup-shaped guide element 57 is expediently mounted on the rack section 27. Part of the height of this rack section 27, measured along the axis of the transverse axis 4, extends into the mounting recess 67. The section containing the drive teeth 28 protrudes from the guide element 57 in the area of ​​the slot-like recess opening 67a.

[0098] Advantageously, the rack section 27 has the form of a square bar with a rectangular cross-sectional profile. Accordingly, the rack section 27 has four longitudinal sides that are perpendicular to each other, with the drive teeth 28 formed on a lower longitudinal side 72 and the guide element 57 mounted on the rack section 27 on the upper longitudinal side 73 opposite the lower longitudinal side 72. The guide element 57 partially overlaps the two lateral longitudinal sides 74 of the rack section 27 extending between the lower longitudinal side 72 and the upper longitudinal side 73, so that the drive teeth 28 still protrude vertically.

[0099] The groove-shaped mounting recess 67 expediently has a rectangular cross-section which corresponds to the cross-sectional contour of the section of the rack section 27 engaging in it.

[0100] The rack section 27 is advantageously designed as a separate rack body 27a with respect to each drive piston 25, 26. It has two opposing axial end faces 75, in the region of which one of the two drive pistons 25, 26 is attached to the rack body 27a. A fastening device 76 for fastening includes, for example, a fastening hole 76a in the rack body 27a opening towards the axial end face 75, into which the drive piston 25, 26 is inserted with a fastening pin 76b projecting axially from the associated piston body 25a, 26a and preferably pressed firmly in place. Each drive piston 25, 26 advantageously rests with its piston body 25a, 26a against the associated axial end face 75 of the rack body 27a.

[0101] In contrast to the illustrated embodiment, the rack section 27 can also be formed integrally with at least one of the piston bodies 25a, 26a.

[0102] The cross-sectional outline of the rack section 27 is expediently projected radially all around by the piston bodies 25a, 26a. Thus, the rack section 27 is arranged at a distance all around from the inner circumferential surface 41 of the circumferential wall section 40.

[0103] Each guide surface 58a, 58b extends in the circumferential direction of the longitudinal axis 62 over the upper longitudinal side 73 of the rack section 27 and also extends a short distance over the two lateral longitudinal sides 74 downwards in the direction of the lower longitudinal side 72 which has the drive teeth 78.

[0104] The guide element 57 can, in principle, be attached to the rack section 27 in any way. Attachment by means of a plug-in connection device 77, which does not require any separate fastening elements, is preferred.

[0105] In the illustrated embodiment, a plug-in connection device 77 is implemented, comprising a mounting pin 78 and a mounting hole 79. A mounting hole 79 is provided in the upper longitudinal side 73 of the rack section 27 and extends towards the drive teeth 28, ending in a blind hole before reaching them. A mounting pin 78 is integrally formed in the mounting recess 67 on the base surface 67b of the guide element 57 and projects within the mounting recess 67 towards the slot-like recess opening 67a, with the mounting pin 78 preferably ending within the mounting recess 67. During the plug-in assembly of the guide element 57 onto the rack section 27 as shown by arrow 82, the mounting pin 78, as shown by arrow 83, enters the mounting hole 79 and is axially fixed therein.Thus, the fastening pin 78 is held in the fastening hole 79 and accordingly, the guide element 57 placed on the rack section 27 is also held on the rack section 27.

[0106] As an example, the fastening pin 78 is held in the fastening hole 79 by force alone. This is achieved by the fastening pin 78 having an overall or partial oversize with respect to the diameter of the fastening hole 79, so that it is radially clamped in the fastening hole 79 when inserted according to arrow 83.

[0107] For example, the fastening pin 78 has a plurality of axially successive annular fastening projections on its outer circumference, which are deformed during the insertion process 83 in the fastening hole 79, thus generating a clamping force. This can be an elastic and, in some cases, even a plastic deformation.

[0108] Alternatively, the plug connection device 77 can also be designed as a snap-fit ​​connection device. In this case, the mounting pin 78 has, for example, at least one locking projection on its outer circumference, which can engage in a locking recess formed peripherally in the mounting hole 78.

[0109] It goes without saying that the fastening can also be a combination of force-fit and form-fit fastening.

[0110] The plug-in connection device 77 can have several cooperating pairs of mounting pins 78 and mounting holes 79, which are spaced apart from each other in the longitudinal direction 30. For example, two pairs of cooperating mounting pins 78 and mounting holes 79 are present.

[0111] It is considered particularly advantageous if, according to the illustrated embodiment, the plug-in connection device 77 has only a single mounting pin 78 and only a single mounting hole 79, wherein the mounting pin 78 is preferably arranged centrally with respect to the longitudinal extent of the guide element 57. The mounting hole 79 is also expediently formed centrally in the rack section 27.

[0112] Advantageously, the rotary drive device 1 is equipped with position detection measures that enable the detection of at least one stroke position or several stroke positions, or of each stroke position, of at least one of the two drive units 24a, 24b. A stroke position is defined as the axial position of the drive unit 24a, 24b relative to the drive housing 2 in the axial direction of the longitudinal axis 16a, 16b.

[0113] The current rotational position of the output unit 38 can be deduced from the detected stroke position of a drive unit 24a, 24b. Knowledge of this rotational position is advantageous for numerous applications of the rotary drive device 1.

[0114] The position detection measures include equipping at least one drive unit 24a, 24b with a permanent magnet 84, which is designed to interact contactlessly with a position sensor device 11, mentioned above, which is fixedly arranged on the drive housing 2. The position sensor device 11, which is expediently arranged in at least one of the mounting grooves 14, contains sensor means that respond to the magnetic field of the permanent magnet 84 and, based on this, output an electrical position signal that can be processed by an electronic control unit used for operating the rotary drive device 1.

[0115] As an example, both drive units 24a, 24b are each equipped with a permanent magnet 84, whereby it is possible to use both permanent magnets 84 simultaneously or only one of the two permanent magnets 84 for position detection. If the rotary drive device 1 contains two drive units 24a, 24b, in principle only one of these drive units 24a, 24b can be equipped with a permanent magnet 84.

[0116] In the illustrated embodiment, the two permanent magnets 84 are designed in the same way and attached to the associated drive unit 24a, 24b.

[0117] In principle, the permanent magnet 84 can be attached directly to a drive unit 24a, 24b. However, it is particularly advantageous if the permanent magnet 84 is fixed to the guide element 57, which is made of plastic material, independently of the drive unit 24a, 24b, so that direct fastening measures to the drive unit 24a, 24b are unnecessary.

[0118] The guide element 57 expediently has a pocket-like receiving recess, designated as a receiving pocket 85, which has a mounting opening 86 oriented radially with respect to the longitudinal axis 62 and facing the outer circumferential region 87 of the guide element 57, through which the permanent magnet 84 is inserted into the receiving pocket 85. The permanent magnet 84, which is preferably formed in one piece and is exemplified as a bar magnet, is expediently clipped into the receiving pocket 85 and thus held in a form-fit manner. However, it can also be fixed in other ways, for example, purely by clamping and / or by an adhesive bond.

[0119] The receiving pocket 85 is advantageously located in the outer circumferential region 87 of the guide element 57, which is radially opposite to the rack section 27, with the mounting opening 86 facing away from the rack section 27. The receiving pocket 85 is advantageously formed in the connecting section 65.

[0120] The receiving pocket 85, and consequently the permanent magnet 84 fixed therein, is advantageously spaced apart from both axial end sections 63, 64 and the guide surfaces 58a, 58b located therein. It is advantageous if the receiving pocket 85, and consequently the permanent magnet 84, is located longitudinally centrally in the guide element 57. It is also advantageous if the receiving pocket 85, and consequently the permanent magnet 84, lies in the main plane 6 of the drive housing 2.

[0121] The magnetic field of the permanent magnet 84 is not affected by the plastic guide element 57 and can therefore act with a high magnetic field strength on the position sensor device 11, which is arranged at a distance from it. This offers the advantage of being able to use materials for the drive unit 24a, 24b where it is irrelevant whether or not they possess magnetic conductivity. In the exemplary embodiment, this is exploited by making at least the rack section 27, but preferably the entire drive unit 24a, 24b, from a cost-effective ferromagnetic steel.

[0122] In the preferred embodiment, the particularly low influence of the ferromagnetic properties of the rack section 27 on the permanent magnet field of the permanent magnet 84 is further achieved by the fact that the receiving pocket 85 for the permanent magnet 84 is formed at the same axial height as the mounting pins 78 of the plug-in connection device 77 in the axial direction of the longitudinal axis 62 of the guide element 57. Since the mounting pin 78 engages in a mounting hole 79 of the rack section 27, there is no material from the rack section 27 locally in that area, so that the immediate area adjacent to the permanent magnet 84 is completely free of ferromagnetic materials.

[0123] The rotary drive device 1 can optionally be equipped with an adjustable stroke presetting device 88, by which the stroke end positions of the two drive units 24a, 24b can be mechanically preset. The stroke presetting device 88 includes, by way of example, two plunger-shaped stroke limiting elements 89, which are screwed into the front end wall 22a and project forward into one of the receiving spaces 15a, 15b. The drive units 24a, 24b can run up against their respective assigned stroke limiting element 89. The axial position of the stroke limiting elements 89 is adjustable and can be fixed in the set position in order to variably preset the stroke of the drive units 24a, 24b and consequently also indirectly the angle of rotation of the rotary output movement 43.

[0124] Advantageously, the stroke control device 88 is equipped with an end-position damping device 92, which dampens the impact of the drive units 24a, 24b on the stroke limiting elements 89. By way of example, the end-position damping device 92 includes rubber-elastic buffer elements which are inserted into the stroke limiting elements 89.

Claims

[1] Rotary drive device (1), comprising a drive housing (2) in which at least one elongated receiving space (15a, 15b) is formed with a longitudinal axis (16a, 16b) parallel to a main axis (6) of the drive housing (2), in which a drive unit (24a, 24b) is received that can be linearly displaced back and forth by controlled fluid application while performing a drive movement (29), which has a longitudinal axis (30) parallel to the longitudinal axis (16a, 16b) of the receiving space (15a, 15b) and which has a rack-like drive toothing (28) on an inner longitudinal side (39), which engages in gearing with the output toothing ring (48) of an output unit (38) rotatable about an axis of rotation (5) perpendicular to the main axis (3) relative to the drive housing (2) inside the drive housing (2), such that the a linear drive movement (29) of the drive unit (24a, 24b) results in a rotary output movement (43) of the output unit (38), wherein the drive unit (24a,24b) in the region of its outer longitudinal side (55) opposite the drive gear (28) by means of a guide device (56) separate with respect to the drive unit (24a, 24b) on a circumferential wall section (40) of the drive housing (2) peripherally bounding the receiving space (15a, 15b), wherein the guide device (56) is combined with the drive unit (24a, 24b) to form an assembly such that it participates in its drive movement (29), and wherein the guide device (56) has at least one guide element (57) attached to the drive unit (24a, 24b), which has at least one guide surface (58a, 58b) on its radial outer side facing away from the drive unit (24a, 24b), with which it slides slidably on the inner circumferential surface (41) of the section of the wall peripherally bounding the receiving space (15a, 15b). circumferential wall section (40) of the drive housing (2) is abutting, , characterized by, that the guide element (57) is arranged in a manner that only partially encloses the drive unit (24a, 24b) while leaving out the drive teeth (28) on the length section of the drive unit (24a, 24b) occupied by the drive teeth (28). [2] Rotary drive device (1) according to claim 1, characterized by , that in the drive housing (2) two drive units (24a, 24b) arranged next to each other with parallel longitudinal alignment and each combined with a guide device (56) to form an assembly are arranged to be linearly displaceable, wherein the output unit (38) is arranged between the two drive units (24a, 24b) and is in gear meshing with its output gear ring (48) with the mutually facing rack-like drive teeth (28) of both drive units (24a, 24b), wherein each drive unit (24a, 24b) is expediently received in its own receiving space (15a, 15b). [3] Rotary drive device (1) according to claim 1 or 2, characterized by , that the at least one guide element (57) of the guide device (56) is formed in one piece and is made of a plastic material. [4] Rotary drive device (1) according to claim 3, characterized by , that the guide device (56) is axially shorter than the rack-like drive toothing (28) and is axially overshot by the drive toothing (28) on both sides. [5] Rotary drive device (1) according to any one of claims 1 to 4, characterized by , that the guide device (56) has only a single guide element (57) attached to the drive unit (24a, 24b). [6] Rotary drive device (1) according to any one of claims 1 to 5, characterized by, that the at least one guide surface (58a, 58b) of the at least one guide element (57) is curved in an arc shape according to the curvature of the inner circumferential surface (41) of the circumferential wall section (40) of the drive housing (2) that defines the receiving space (15a, 15b), wherein the guide surface (58a, 58b) expediently extends over an arc angle which is in the range of 180 degrees. [7] Rotary drive device (1) according to any one of claims 1 to 6, characterized by , that the at least one guide element (57) of the guide device (56) is shell-shaped and has a groove-like mounting recess (67) on its radial inner side (66) facing the drive unit (24a, 24b), with which it is mounted radially outside in a rider-like manner onto a rack section (27) of the drive unit (24a, 24b) having the drive teeth (28), wherein the rack section (27) plunges into the mounting recess (67). [8] Rotary drive device (1) according to any one of claims 1 to 7, characterized by , that the at least one guide element (57) of the guide device (56) is attached to the drive unit (24a, 24b) by means of a plug connection device (77). [9] Rotary drive device (1) according to claim 8, characterized by , that the at least one guide element (57) of the guide device (56) has, in the area of ​​its radial inner side (66) facing the drive unit (24a, 24b), at least one mounting pin (78) belonging to the plug connection device (77) and projecting radially inwards, which is inserted into a mounting hole (79) of the drive unit (24a, 24b) also belonging to the plug connection device (77) and is held in the mounting hole (79), wherein the mounting pin (78) is expediently fixed to the drive unit (24a, 24b) in the mounting hole (79) by friction and / or form locking. [10] Rotary drive device (1) according to any one of claims 1 to 9, characterized by , that the at least one guide element (57) of the guide device (56) has a longitudinal axis (62) parallel to the longitudinal axis (30) of the drive unit (24a, 24b) and has several strip-shaped guide surfaces (58a, 58b) arranged axially apart from each other on its outer side, each extending arcuately a portion of the longitudinal axis (62) of the guide element (57), wherein the guide element (57) expediently has exactly two such guide surfaces (58a, 58b). [11] Rotary drive device (1) according to claim 10, characterized by, that the at least one guide element (57) of the guide device (56) has two strip-shaped guide surfaces (58a, 58b) which are each arranged on one of the two axial end sections (63, 64) of the guide element (57), wherein the guide element (57) has a connecting section (65) extending between the two axial end sections (63, 64) which is continuously spaced apart from the circumferential wall section (40) of the drive housing (2), so that the guide element (57) bears against the drive housing (2) exclusively via the two guide surfaces (58a, 58b). [12] Rotary drive device (1) according to any one of claims 1 to 11, characterized by, that at least one guide element (57) of the guide device (56) is equipped with a permanent magnet (84) for position detection of the drive unit (24a, 24b), wherein a rack section (27) of the drive unit (24a, 24b) having the rack-like drive toothing (28) is expediently made of a steel material with ferromagnetic properties. [13] Rotary drive device (1) according to claim 12, characterized by , that the permanent magnet (84) is fixed in a receiving pocket (85) formed in the guide element (57), which is open radially outwards and is expediently formed in a region of the guide element (57) located between two axially spaced guide surfaces (58a, 58b). [14] Rotary drive device (1) according to claim 13 in conjunction with claim 9, characterized by, that the receiving pocket (85) for the permanent magnet (84) is formed at the same axial height as a mounting pin (78) of the plug connection device (77) with respect to a longitudinal axis (62) of the guide element (57) parallel to the longitudinal axis (30) of the drive unit (24a, 24b). [15] Rotary drive device (1) according to any one of claims 1 to 14, characterized by, that each drive unit (24a, 24b) has at least one drive piston (25, 26) which has a rubber-elastic sealing ring (32) which slides slidably and seals against the inner circumferential surface (41) of the circumferential wall section (40) of the drive housing (2) which peripherally delimits the receiving space (15a, 15b), wherein the drive piston (25, 26) delimits a drive chamber (33, 34) in the receiving space (15a, 15b) which can be pressurized with a fluidic pressure medium to generate the drive movement (29) of the drive unit (24a, 24b) and wherein a rack section (27) having the rack-like drive teeth (28) projects axially from the drive piston (25, 26). [16] Rotary drive device (1) according to claim 15, characterized by, that each drive unit (24a, 24b) has two axially spaced drive pistons (25, 26) which in the receiving space (15a, 15b) each define one of two fluid-actuated drive chambers (33, 34) and which are connected to each other by a rack section (27). [17] Rotary drive device (1) according to claim 15 or 16, characterized by , that the rack section (27) of the drive unit (24a, 24b) is a separate rack body (27a) with respect to each drive piston (25, 26) of the drive unit (24a, 24b), on which each drive piston (25, 26) of the drive unit (24a, 24b) is fixed by means of a fastening device (76) and which is expediently designed as a square bar with a rectangular cross-sectional profile, which has the drive teeth (28) on one of its four longitudinal sides. [18] Rotary drive device (1) according to claim 17, characterized by, that the drive teeth (28) extend over the entire axial length of the rack body (27a) and that the two drive pistons (25, 26) each connect directly axially to the drive teeth (28). [19] Rotary drive device (1) according to any one of claims 15 to 18, characterized by , that the at least one drive piston (25, 26) is designed without a guide ring and only rests on the drive housing (2) via the sealing ring (32).

Images