EP1519055A2 - Fluid actuator - Google Patents

Abstract

The fluid drive between two relatively movable components has at least one hydraulic or pneumatic drive element consisting of a hollow component (1) which is formed at least partially like a bellows. Stretch resistant ring elements (4) encompass the hollow component in each individual fold, and the stretch resistant ring on at least one side of the hollow component is connected via an extension resistant connection to at least one of the two force action sections (3) of the drive element. An independent claim is included for an articulated drive incorporating the proposed fluid drive for two components interconnected by a joint.

Description

The invention relates to a fluidic drive between two movably arranged components according to the first Claim.

Such drives serve as drives for translatory movements, but also for pan or rotary movements predominantly in the fields of robotics or prosthetics. They include in Essentially at least one hydraulic or pneumatic Drive element, which two movably arranged to one another Bridging components. The drive elements are each over at least one force application area to each of the two Components connected. Preferably, the drive element consists from a hollow body with an inlet and outlet a working fluid.

In DE-AS 23 45 856 a fluidic drive in the frame a manipulator has been described, which except for the bellows-like Form corresponds to the previous description. Of the Drive is as a pressure bubble laterally next to the joint and between the opposing faces of two components used, this forced apart by a swelling of the drive be and a pan or turn around cause a hinge axis. A stretch-resistant limiter cover the bladder limits the volume of inflation of the drive.

The force introduction areas of this drive extend on the entire faces. Since no special means one Leadership of the drive are provided, they also change during the inflation of the drive. Also, the drive is like that designed that inflates the drive approximately evenly in all directions. As a result, limited not only the transmittable force, but also the tilt angle, while on the other hand, the thickness of the joint with increasing Inflation increases.

On this basis, it is an object of the invention to provide a fluidic Propose drive with a guided hollow body, which for the transmission of higher forces in connection with big strokes or swivel angles already with a small one Throughput of working fluid is suitable. Above all, the drive should be in each state filled with working fluid a compact contour maintained and thus suitable for use in cramped conditions especially suitable.

The object is achieved by a fluidic drive with the characterizing Characteristics of claim 1 solved. Advantageous embodiments are given in the subclaims.

The essential features of the invention relate to the hollow body as well as his leadership.

The hollow body is fluid-tight and at least partially bellows-like shaped and has next to a fluid-tight wall an inlet and outlet of a working fluid. He instructs the introduction of the working fluid, d. H. in the aforementioned puffing, a predetermined expansion preferred direction in a Direction, which by the bellows-like configuration is predetermined. A laterally on the hollow body expands Intumescent volume is just like the required installation dimensions Already drastically reduced by the aforementioned design. Also, in a particularly advantageous manner by the already structurally related increased soapiness of the hollow body opposite lateral bulge for a particular stroke or required for the pivotal or rotary movement amount of working fluid limited. Since the cross-sectional area is orthogonal changes only slightly to the stroke direction, can also the lifting force with bellows-like hollow volume also significantly dosed better and in small areas. The expansion of the hollow body is over at least two force introduction areas transferred to adjacent components.

It is irrelevant whether the wall of the hollow body single-walled or multi-walled. For example, it offers on, an elastic fluid-tight inner wall, for example of an elastomer (e.g., rubber) with a stretch-stiffness Outside wall, for example, to combine a fabric coat. For single-walled versions, e.g. elastic Materials which either have sufficient rigidity or with additionally incorporated reinforcements are stiffened.

The leadership of the hollow body is predominantly within the scope of the invention by stretch-resistant ring elements which the bellows-like Enclose hollow bodies in each individual fold and in the event that they are not integrated in the wall are to be guided by this. Further, they are on at least one side of the bellows-like hollow body over a Dehnsteife connection with at least one of the two force application areas connected. In particular, when the hollow body not as a swivel drive but as a translatory Drive serves, it also offers, more rigid connections Provide distributed over the circumference of the hollow body.

Basically, the ring elements comprise all components which enclose at least one cross-section stretch-rigid and thereby do not exceed a certain height, material thickness or thickness, i.e. For example, sheets, foils or plates with breakthroughs. It is also within the scope of the invention, if these ring elements in the wall as flexible inserts such as Wires or threads are integrated.

The stretch-rigid connection serves as a guide for the ring elements and does not have to be connected directly to the ring elements. It is quite sufficient if the ring elements on suitable Intermediate components are coupled to the connection. This is For example, the case when the connection is not on the ring elements directly but on the outer areas of the Folding, d. H. engages the wall of the hollow body while the ring elements through the inner wall portions of the Folds are sufficiently fixed and guided. The ring elements are doing form-fitting in the folds, d. H. to the Make the relatively small cross-sectional areas of the bellows guided.

Dehnsteif means in this connection with all mentioned Ring elements, walls or connections an exclusion of a unwanted stretching. However, stretch stiffness is included in the frame the invention a tolerable or intentional extensibility of Dehnsteifen components, for example, to reduce local power surges or to avoid damage in the fluidic drive. In particular, let's look at the function here referred to the said stretch-stiff components, which, for example the avoidance of lateral bulges of the hollow body on the one hand and ensuring a guided and so on clear movement of the hollow body and thus also of the drive element serve.

The connection of the ring elements with a force application area takes place on one side of the hollow body and limits it the maximum removal of the ring elements from the force application areas. Alone through this guidance becomes an uncontrolled Breaking of the hollow body avoided, bringing itself also larger forces from the bellows-like hollow body over the Transfer of force application areas to the two components to let.

In the case that the stretch stiff connection with more than one Force introduction area, this also limits the maximum stroke or swivel angle of the drive. On the special Guide the ring elements at maximum lift or swivel angle through the taut connection in this position being point out.

The bellows-like hollow body has in the deflated state with a thin wall and thin ring elements a particularly short Design on. In this way, the fluidic drive can be even in cramped conditions between the faces two connected to a joint components, for example in the context of the disclosed in DE-AS 23 45 856 manipulator use and is basically due to the aforementioned Guide elements and the unidirectional expansion of the bellows-like Hollow body practically for all sorts Swing angle between the two components.

Fig. 1 eine erste Ausführungsform mit fadenförmiger Verbindung und an diese direkt befestigten fadenförmigen Ringelementen und separater Armierung,

Fig. 2 eine zweite Ausführungsform mit fadenförmiger Verbindung und an diese nicht direkt befestigten fadenförmigen Ringelementen

Fig. 3 eine dritte Ausführungsform mit einer dehnsteifen Verbindung, umfassend mindestens eine einseitige Verklebung,

Fig. 4 eine vierte Ausführungsform mit einer Verbindung in Form von einseitig miteinander vernähten Faltungen,

Fig. 5 eine fünfte Ausführungsform, wobei die Verbindung und die Ringelemente durch eine entsprechend konstruktiv gestaltete dehnsteife Wandung gebildet werden,

Fig. 6 a und b eine sechste Ausführungsform mit Ringelemente und Verbindung aus Folienmaterial bzw. ein Schnittmuster eines dieser Ringelemente mit Verbindung sowie

Fig. 7 a und b eine weitere Ausführungsform als Schwenkantrieb mit zwei parallel geschalteten dehnstarren Verbindungen für ein künstliches Fingergelenk in zwei Winkelstellungen.

The invention will be explained in more detail below with reference to embodiments with reference to figures. Show it

1 shows a first embodiment with thread-like compound and directly attached to this thread-like ring elements and separate reinforcement,

Fig. 2 shows a second embodiment with thread-like compound and not directly attached to this thread-like ring elements

3 shows a third embodiment with a stretch-rigid connection, comprising at least one one-sided bond,

4 shows a fourth embodiment with a connection in the form of unilaterally sewn-together folds,

5 shows a fifth embodiment, wherein the connection and the ring elements are formed by a structurally designed stretch-rigid wall,

Fig. 6 a and b, a sixth embodiment with ring elements and compound of film material or a pattern of one of these ring elements with compound and

Fig. 7 a and b another embodiment as a pivot drive with two parallel stretch rigid connections for an artificial finger joint in two angular positions.

All figures show a fluidic drive with a hollow body 1 with at least one inlet and outlet 2 as a hydraulic or pneumatic drive element. The hollow body is in each of the embodiment shown is at least partially bellows-like designed. Further, each of a surface existing force introduction areas 3, the ring elements 4 in the folds 5 and the stretch-rigid connection 6 of respective embodiment disclosed.

FIGS. 1 and 2 show embodiments in which compound 6 and ring members 4 are formed by threads or wires. During ring elements and connection in the context of the first embodiment (Fig. 1) are directly connected to each other, for example via knotting, gluing or through under the Ring elements pulled through connections, is the connection 6 in the second embodiment (Figure 2) directly to the attached outside areas of the folds 5. It will be the ring elements 4 by form-fitting through the folds and thereby indirectly guided by the connection 6. It can the convolutions, as shown in Fig. 1, by an additional but pliable but rigid reinforcement 16, to the Force introduction areas 3 and fixed to the ring elements is, in addition to uncontrolled puffing of the hollow body in addition and locally (for example, in the case of rotary actuators, the outside area) to be protected. The force introduction areas 3 are in both Figures by way of example for all other embodiments designed as mushroom or helical holders, over the hollow body coated and glued fluid-tight, screwed, jammed or vulcanized. It offers it is up to the shaft of the bracket as an inlet or outlet hollow and outside with a thread for a not illustrated lock nut for additional clamping of the Wall between locknut and bracket head on the one hand or for fixing the bracket to a component on the other to provide.

Fig. 3, however, shows an embodiment in which the stretch-stiff Compound 6 comprises at least one one-sided bond 8, which surrounds the ring elements 4 on one side. there the gluing serves only as a filling connection between the bellows-like hollow body 1 and a stretch-rigid component such as a belt 7. In another, not shown embodiment, the bond 8 either even sufficient rigidity on, basically they limp, remains or becomes by integration of reinforcing components, such as fibers, accordingly strengthened.

Fig. 4 discloses a fourth embodiment with a connection 6 in the form of unilaterally stitched folds, which are rigid with the force introduction region 3 (for example by Threads) are connected. In contrast to the aforementioned figures includes the compound besides additional components such as threads or adhesive especially rigid wall areas between the individual preferably punctiform seams 14 at the folds.

Fig. 5 shows a fifth embodiment in which the connection and the ring elements by a correspondingly constructive designed to be formed stretch-rigid wall, the fold-shaped Design of the hollow body and thus a greater elasticity the hollow body is only on one side (in Fig. 5, the upper) present, while the smooth, the wrinkled opposite lying area formed by the stretch-rigid wall and thus represents the stretch-tight connection 6.

Hollow body as shown in Fig. 5 can be due to the small diameter of the inlet and outlet 2 often no longer by a conventional single-stage vulcanization process to one Make mold core. The production therefore takes place, for example by a two-stage molding process in a first step, the bellows-like area of the Hollow body e.g. made of elastomer with a vulcanization process is produced on the first in a second step smooth area of an elastomer, if necessary with an additional Dehnsteifen reinforcement by a second vulcanization process is applied fluid-tight.

In a sixth embodiment, basically disclosed in 6 a and b, are flexible connection 6, ring elements. 4 and fastening 9 of the connection 6 to the attachment areas 3 as at least one guide component 10 made of film material produced. A cutting pattern for such a guide component 10 shows FIG. 6 b. Fig. 6 a shows the application several of these guide components on a bellows-like Hollow body 1, wherein in the illustrated version each Folding with its own guide component with the force application area connected is. Other possible versions include also a coupling of two or more convolutions with each other or at least one convolution with one or more Fastening areas via a respective guide component. When used as a rotary actuator connections can 6 not only, as shown in Fig. 6 a, on one side, but additionally provided on the opposite side become.

The installation of the fluidic drive to two with a joint 11th connected components 12 is shown by way of example in Fig. 7 a and b. The components 12 each have an abutment 15 for the inclusion of the force introduction regions of the hollow body. 1 which is in a pivoting position (Fig. 7 a) preferably parallel and with the introduction of a working fluid pressed into the hollow body by this become. The connections are, as already in the context of Fifth embodiment described on both sides of the hollow body. 1 attached, in particular, the outer connection 13 is not only avoids breaking out of the hollow body, but also one maximum swing angle predetermines (Fig. 6 b).

LIST OF REFERENCE NUMBERS

1

hollow body

2

Inlet and outlet

3

Force application areas

4

ring elements

5

folds

6

rigid connection

7

belt

8th

bonding

9

attachment

10

guide component

11

joint

12

component

13

outer connection

14

seam

15

thrust bearing

16

reinforcement

Claims (7)

Fluidic drive between two movably arranged components, comprising at least one hydraulic or pneumatic drive element each with at least one force introduction region on both components, wherein the drive element consists of a hollow body with an inlet and outlet of a working fluid,
characterized in that a) the hollow body is shaped at least partially bellows-like, b) stretch-rigid ring elements enclose the bellows-like hollow body in each individual fold and c) the stretch-stiff ring elements is connected on at least one side of the bellows-like hollow body via a stretch-rigid connection with at least one of the two force introduction regions. Fluidic drive according to claim 1, characterized in that the bellows-like hollow body has a flexurally soft and rigid wall. Fluidic drive according to claim 2, characterized in that the stretch-rigid wall consists of a fabric-reinforced material or is composed of an elastic inner wall and a stretch-rigid outer wall. Fluidic drive according to one of claims 1 to 3, characterized in that the stretch-rigid ring elements and the rigid connection are made of a plastic film. Fluidic drive according to one of claims 1 to 3, characterized in that the stretch-rigid ring elements and the rigid connection consist of thread. Fluidic drive according to one of claims 1 to 3, characterized in that the stretch-rigid compound comprises a one-sided suturing, vulcanized connection or adhesion of the folds to each other. Swivel drive comprising a fluidic drive according to a of the preceding claims for two by a joint interconnected components.

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