DE102007017417A1 - Actuator for use as e.g. gripping device, has contraction drive griping working elements, which covers element connection at opposite sides, with both end sections of drive, where contraction hose passes to hinge region of connection - Google Patents

Abstract

The actuator (1) has actuator units with bend-proof working elements (4) that are articulately linked to each other by forming a link chain so that the elements are pivoted relative to each other in a working plane. A tension element is actuated by fluid force, and a contraction drive (13) having a contraction hose (24) is formed, where the hose contracts during fluid admission in its interior space. The drive grips the working elements, which covers an element connection at opposite sides, with both end sections of the drive, where the hose passes to a hinge region (6) of the connection.

Description

The The invention relates to an actuator with at least one multi-membered Actuator unit, which arranged several in a row consecutively rigid working members containing the formation of a Link chain are hinged together so articulated that they are pivotable relative to each other in a working plane, wherein along at least one of the working members containing Linking a flexible flexure having a longitudinal shape Pulling element extends, which at the at least one joint region passes through the member compound, so that its a pulling force causing Activation bring about a bending of this linkage can.

The DE 24 33 710 A1 discloses an actuator of this type as part of a human hand replicating prosthesis. A plurality of multi-limb actuator units representing the fingers and the middle hand each include a plurality of working members combined into a link chain which are pivotable relative to each other to curve a respective link chain in a working plane, for example to carry out a picking operation. The curvature force is generated by an external, attached to the forearm pneumatic drive and transmitted via a traction cable designed as a traction element on the respective link chain. In this case, the pull rope extends longitudinally next to the working members to be attached to the last working member of the link chain. Although the gripping function of a hand or the finger of a hand can be mimicked quite well with this known actuator. However, the space required to house the individual components, including the pneumatic drive, is relatively large and becomes even greater when measures are to be taken to allow independent activation of multiple actuator units.

It It is therefore an object of the present invention to provide an actuator of the aforementioned type so that it is in a compact Construction can be realized.

to Solution to this problem is provided that the tension element from a fluid-actuated one at Fluid supply to its interior shortening contraction tube having formed contracting drive, with its two End sections at the two the linkage on opposite Being the end of the work is attacking its members Contraction hose the at least one joint region of the linkage happens.

at Such an actuator is used to bend a linkage required traction no longer from an external fluid drive generated, but by acting directly as a tension element Contraction drive, which is arranged on the link chain and extending along this. This contraction drive contains as a core component in an internal pressurization shortening contraction tube, so when activated of the contraction drive in the final linkage Working links a tensile force is initiated, a curving of the linkage can bring about by putting together pivoted articulated work members relative to each other. at this pivoting is the bend flexible contraction tube in the joint areas with bent, so he can the curvature join the link easily.

Of the Linkage contains at least two articulated with each other connected working members, but can easily a larger Include number hingedly interconnected work members. In a more than two-member link chain consists of by a single contraction drive operable linkage preferably from all Ar beitsgliedern the link chain. However, it would also be possible here, the link chain functional into several member associations, each with its own Contraction drive is assigned, in particular if at certain Joint areas an independent kinking the link chain should be enabled.

For the contraction drive is particularly recommended a structure, as for example from the WO 00/61952 A1 or from the EP 1 602 831 B1 evident. Accordingly, the contraction tube expediently contains a rubber-elastic tube body, to which a coaxial strand structure is assigned, which is expediently embedded in the wall of the tube body. The strand structure may have a crossover configuration, similar to a grid structure. If the interior of the contraction tube is acted on by a drive fluid, the tube body widens radially, which leads to a shortening of the thereby deforming strand structure, with the consequence of tappable at the end portions of the contraction drive tensile forces.

Around a precisely defined curvature behavior of the link chain To ensure it is beneficial when the contraction drive is arranged on the link chain such that its traction axis with transverse offset passes by the joint area or areas of the linkage.

advantageous Further developments of the invention will become apparent from the dependent claims out.

At least an actuator unit can form a movable finger. in this connection it may in particular be a multi-limbed finger. Without Further, several, in particular finger-like designed Actuator units are arranged side by side, for example, to imitate the fingers of a human hand. Several actuator units may also include a common working member which attack the contraction drives of several actuator units.

Of the Contraction drive could in principle be alongside extend next to and outside the associated link chain. However, more advantageous is an integration such that the contraction drive runs inside the link chain. This can in particular about have a hollow structure.

In Connection with an integration of the contraction drive in the Link chain, it is advantageous if one or more working links at its the curvature center of the Aktuatorein unit facing inner longitudinal side over at least one opening through which the contraction tube passes upon activation of the contraction drive radially outward can bulge. The bulging wall section of the contraction tube can advantageously as a resilient gripping surface be used when the actuator unit, for example, as Gripping device is designed.

For the individual working members are recommended in particular a dish-like Construction. At the center of curvature facing inner longitudinal side can one or more working members at least one belt element have, which encloses the contraction tube and holding him back inside the link chain if an activation takes place. The belt elements are resistant to tension, otherwise they can but be flexible. Appropriately, acts but it is a total of rigid elements, which expediently integral parts of the working members are.

For the actuator are versatile uses conceivable. It can be used in particular as a gripping device, be it in an embodiment as a replicated hand of a humanoid robot or as an independent gripper for handling of objects in manufacturing and assembly technology and / or in the packaging industry. The actuator can also be called Clamping act to workpieces to be machined releasably against a base to tension, whereby he to the Place otherwise usual Pratzenspanner or toggle clamp can occur. Also in prosthetics, the actuator can easily be used. The listed application areas are not to be understood as final.

following The invention will be more apparent from the accompanying drawings explained. In this show:

1 a preferred first design of the actuator according to the invention with a multi-unit actuator unit in the unactuated initial state,

2 the actuator off 1 in an actuated state with a curved link chain,

3 a rear view of the actuator 2 with viewing direction according to arrow III, wherein a dot-dash line a possible embodiment is indicated as an actuator with a plurality of actuator units, and

4 a longitudinal section through the actuated actuator according to section line IV-IV 3 ,

The drawing shows a reference in its entirety 1 designated actuator 1 that of a rod in the unactuated initial state actuator unit 2 is formed. The actuator unit 2 is multi-limbed and contains several in the direction of its longitudinal axis 3 strung together rigid working members 4 , forming a link chain 5 in between directly consecutive work members 4 lying joint areas 6 are pivotally linked together.

In the joint areas 6 can the link chain 5 by relative pivoting of there hinged to each other work members 4 in a work plane 7 be bent. The work plane 7 runs in 2 parallel to the drawing plane and falls in 4 with the drawing plane together.

Through the joint areas 6 each becomes a hinge axis 8th Are defined. The joint axes 8th all joint areas 6 expediently run parallel to each other and at right angles to the working plane 7 ,

Conveniently, that is from the working members 4 existing link chain 5 executed as a hollow structure. The wall of the working members 4 defines one between all working members 4 continuous reception room 12 for a still to be explained, actuated by fluid force contraction drive 13 ,

The individual work members 4 are preferably substantially cup-shaped. They each have a shell-shaped or channel-shaped profiled base section 14 with - as in 3 at 16 apparent - substantially U-shaped cross-section.

So that no axle body the receiving space 12 crosses, standing in the direction of the longitudinal axis 3 neighboring working members 4 to define their common hinge axis 8th at two in the axial direction of the hinge axis 8th spaced bearings 15 in pivotal engagement with each other. For example, protrude from the base section 14 of a working member 4 two in the axial direction of the joint axis 8th spaced bearing arms 17 away, each with a circular contoured bearing extension 18 carry in a complementarily contoured bearing recess 19 of the other working member 4 rotatably engaged.

The mutually facing end faces of adjacent working members 4 are particularly designed so that starting from the in 1 shown extended initial state pivoting in only one direction is possible. At a pivoting in the opposite direction, the working members block 4 with their abutting base sections 14 each other.

By pivoting the hinged to each other working members 4 can be a curved course of the link chain 5 get, as he exemplifies 2 and 4 evident. The curvature does not have to be uniform. In particular, the work members articulated between each other directly 4 currently occurring swivel angle within the link chain 5 vary.

The link chain 5 becomes in the direction of the longitudinal axis 3 opposite sides of a first and a second end member 4a . 4b the working links 4 completed. For a bipartite link chain only 5 are the two final members 4a . 4b the only two working members 4 , As needed, between the two final members 4a . 4b any number of as intermediate links 4c working members 4 be incorporated, wherein in the embodiment, two such intermediate links 4c available.

The already mentioned contraction drive 13 is in the recording room 12 and thus inside the link chain 5 added. In doing so, he goes through one of all available working elements 4 composite linkage. With its one, first end section 22 it ends within the first closing term 4a , and with its opposite second end portion 23 it ends inside the second end member 4b , Here he passes all joint areas 6 the link chain 5 ,

The embedding of the contraction drive 13 in the link chain 5 on the one hand creates compact dimensions and on the other hand ensures a protected housing of the contraction drive 13 , In this respect, this design has advantages over a basically also possible embodiment in which the contraction drive 13 outside the link chain 5 alongside this extends.

With its two end sections 22 . 23 is the contraction drive 13 at the first and second end member, respectively 4a . 4b so fastened that he is in these working members 4 can initiate a tensile force.

The contraction drive 13 has a longitudinal extent, wherein it is elastically bendable transversely to this. The bending elasticity comes from a contraction tube 24 forth, between the two end sections 22 . 23 extends.

Like the enlarged detail of the 4 can be seen contains the contraction tube 24 a hose body made of material with rubber-elastic properties 25 and a coaxial to this hose body 25 arranged strand structure 26 , The hose body 25 is preferably made of rubber or an elastomeric material. The strand structure 26 consists of a variety of bending flexible, but at the same time a very high tensile strength having individual strands, which consist for example of textile fibers and / or synthetic fibers, a multi-fiber structure is possible. Conveniently, the strand structure 26 completely in the wall of the hose body 25 embedded so that it is protected from damage. The individual strands of the strand structure 26 are arranged in a cross-over configuration so that a grid-like configuration with a plurality of diamond-like areas results in a radial top view.

The end is the contraction tube 24 under sealing tension-resistant at the two end portions 22 . 23 fastened, which are in particular independent head pieces, in particular made of metal or plastic material.

The first graduation member 4a fixed first end section 22 is from a control channel 27 interspersed with that of the contraction tube 24 enclosed interior 28 connected is. About one to the control channel 27 connected fluid line 32 For example, a working fluid may be added or removed to provide controlled fluid admission to the interior 28 cause.

In the case of such an internal pressure application, the tube body occupying a substantially linear expanded position in the unpressurized state undergoes a 25 a radial expansion, resulting in a distortion of the strand structure 26 formed Rautengitters causes, resulting in an axial shortening of the strand structure 26 and therefore of the whole th contraction tube 24 results. Thus, the two end sections become 22 . 23 acted upon in the sense of a mutual axial approach with a tensile force. This traction is in the two final members 4a . 4b the link chain 5 initiated.

In the depressurized, ie deactivated state of the contraction drive 13 takes the actuator unit 2 from 1 shown extended position with a linear course of its longitudinal axis 3 one. Upon activation of the contraction drive 13 by fluid admission of the interior 28 become the two end sections 22 . 23 drawn together. An axial shortening of the link chain 5 However, it is not possible because the individual working members 4 in the direction of the longitudinal axis 3 support each other. Thus, the link chain bends 5 in the joint areas 6 and experiences a more or less strong curvature depending on the extent of the fluid loading, for example according to FIG 2 and 4 ,

To initiate this curving process easily, is a pending course of the contraction drive 13 advantageous in which its coincident with its longitudinal axis pull axis 33 even in the deactivated initial state to the side of the desired center of curvature out with transverse offset at the joint axes 8th passes.

Is by appropriate control of the internal pressure in the contraction tube 24 dismantled again, the contraction drive returns 13 due to the rubber elasticity of the contraction tube 24 automatically back to the extended position. To improve the response but you can provide supportive return means, for example, return springs or active actuated Rückstellaktuatoren.

Due to its bending elasticity, it is the contraction tube 24 easily possible in the joint areas 6 where the working links 4 Fear each other, turn off. So he can the curvature of the link chain 5 without risk of damage.

Particularly advantageous embodiments for a in the actuator unit 2 usable contraction drive 13 reveal, for example, the WO 00/61952 A1 and the EP 1 602 831 B1 ,

While in the embodiment of the contraction drive 13 influenceable linkage of the totality of the existing link chain 5 There are also conceivable embodiments in which within one and the same link chain 5 several contraction drives 13 are arranged one behind the other, each one on only one part of the working links of the link chain 5 affect comprehensive linkage.

Out The drawing shows that based on the invention Principle of realizing actuator units in a particularly advantageous manner, which form a movable finger, in particular a multi-membered Finger. For example, prostheses can be used on this basis be realized or even components of a hand of a humanoid Robot. Likewise can be advantageous on this basis realize a gripping device, in particular a multi-finger gripper, with which to hold workpieces or other objects leave to reposition.

Also a clamping device can be easily realized, with the workpieces to be processed against a base can be stretched.

Normally, when using the actuator, the first termination member 4a held so that the other working members arranged thereon 4 . 4c . 4b perform the bending operation causing pivotal movement.

For example, to realize a multi-finger gripper, multiple actuator units 2 in the in 3 indicated manner be juxtaposed. There is the possibility of several actuator units 2 a common first final member 4a assign to which the contraction drives 13 all actuator units 2 attack at one end.

Due to the shell structure of the working members 4 and their corresponding orientation is the link chain 5 at the curvature center facing longitudinal side open. Thus the contraction drive 13 and in particular its contraction tube 24 at curving the link chain 5 nevertheless within the reception room 12 remains, he is in the range offe NEN longitudinal side of the receiving space 12 from several in the direction of the longitudinal axis 3 with spaced apart belt elements 34 embraced at the base sections 14 are attached. Such belt elements 34 are located in particular in the joint areas 6 , Every working member 4 can one or more such belt elements 34 exhibit.

In the embodiment, have the first termination member 4a and every link 4c via a belt element 34 , with a small axial distance to the associated hinge axis 8th are arranged. By way of example, a belt element each extends 34 between the two bearing arms 17 a respective working member 4 ,

The belt elements 34 are in particular designed as a rigid, bow-shaped elements, which advantageously integrally with the associated Ba sisabschnitt 14 are formed. However, they could easily have a certain flexibility and for example consist of a tensile fiber material.

Between adjacent belt elements 34 as well as between the last belt elements 34 and the attachment points 35 for the end sections 22 . 23 of the contraction drive 13 remain uncovered openings 36 , These allow the contraction tube 24 , to the center of curvature sections of the link chain 5 to bulge out when the contraction drive 13 is activated. In the 2 well-visible bulged sections 37 of the contraction tube 24 can be used to protect an object gently. Also, a secure retention of objects can be ensured by a correspondingly high coefficient of friction of the tubular body material.

At the attachment points 35 can the two end sections 22 . 23 by any suitable fastening means 38 at the final member there 4a . 4b be fixed. By way of example, the parts mentioned are pinned together. Without claim to completeness of the list, a screw connection would be possible.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 2433710 A1 [0002]
• WO 00/61952 A1 [0007, 0041]
• EP 1602831 B1 [0007, 0041]

Claims (19)

Actuator, with at least one multi-unit actuator unit ( 2 ), which comprises a plurality of bending-resistant workpieces ( 4 ) forming a link chain ( 5 ) are hinged together in such a way that they are in a working plane ( 7 ) are pivotable relative to each other, wherein along at least one of the plurality of working members ( 4 ) having a longitudinal shape exhibiting flexurally flexible tension member extending at the at least one hinge region ( 6 ) passes through the linkage, so that its activation causing a tensile force can cause a bending of this linkage, characterized in that the tension element of an actuated by fluid force, one in Fluidbeaufschlagung its interior ( 28 ) shortening contraction tube ( 24 ) having contraction drive ( 13 ) is formed, with its two end portions ( 22 . 23 ) at the two members joining the link on opposite sides ( 4 . 4a . 4b ), whereby its contraction tube ( 24 ) the at least one joint region ( 6 ) of the link network happens. Actuator according to claim 1, characterized in that the contraction drive ( 13 ) is arranged so that its longitudinal traction axis ( 33 ) with transverse offset at the at least one hinge region ( 6 ) of the linkage associated joint axis ( 8th ) passes by. Actuator according to claim 1 or 2, characterized in that with a contraction drive ( 13 ) equipped members from all members of the working group ( 4 ) of the link chain ( 5 ). Actuator according to one of claims 1 to 3, characterized in that at least one actuator unit ( 2 ) forms a movable finger. Actuator according to one of claims 1 to 4, characterized in that at least one actuator unit ( 2 ) forms a multi-limbed finger. Actuator according to one of claims 1 to 5, characterized by a plurality of juxtaposed actuator units ( 2 ). Actuator according to one of Claims 1 to 6, characterized by a plurality of actuator units ( 2 ), which is a common working link ( 4 . 4a ), on which the contraction drives ( 13 ) of several actuator units ( 2 ) attack at one end. Actuator according to one of claims 1 to 7, characterized in that the contraction drive ( 13 ) inside the link chain ( 5 ). Actuator according to claim 8, characterized in that the working members ( 4 ) at least partially at its the center of curvature of the link chain ( 5 ) facing inner longitudinal side via at least one opening ( 36 ) through which the contraction tube ( 24 ) upon activation of the contraction drive ( 13 ) can bulge outward. Actuator according to claim 9, characterized in that the working members ( 4 ) are formed like a shell. Actuator according to one of claims 8 to 10, characterized in that at least one of the working members ( 4 ) in the region of its center of curvature of the link chain ( 5 ) facing inner longitudinal side at least one of the contraction tube ( 24 ) surrounding belt element ( 34 ) having the contraction tube ( 24 ) at an exit from the link chain ( 5 ) hinders. Actuator according to claim 11, characterized in that at least one belt element ( 34 ) a joint area ( 6 ) assigned. Actuator according to one of claims 11 or 12, characterized in that the belt element ( 34 ) is rigid. Actuator according to claim 13, characterized in that the belt element ( 34 ) an integral part of the working member ( 4 ). Actuator according to one of claims 11 to 14, characterized by several along the link chain ( 5 ) with spaced-apart belt elements ( 34 ). Actuator according to one of claims 1 to 15, characterized in that the contraction tube ( 24 ) a hose body consisting of material with rubber-elastic properties ( 25 ) and one to the hose body ( 25 ) coaxial, in the wall expediently embedded strand structure ( 26 ) having. Actuator according to one of claims 1 to 16, characterized in that it forms a gripping device. Actuator according to one of claims 1 to 16, characterized in that it forms a tensioning device. Actuator according to one of claims 1 to 18, characterized in that it is a component a hand of a robot forms.