DE19531097A1 - Fluid-actuated operating device, with net sleeve clamped by ring - Google Patents

Abstract

The device has an elastic rubber hose element (1), which is impermeable to gases, and which can be acted upon internally by a pressurised fluid. The element is surrounded by a sleeve (3), with at least one end (8) which is fastened to a head component (12) by clamping equipment (17). The sleeve has a mesh or net structure, whose length contracts when the internal pressure of the hose causes the sleeve to expand radially, in order to apply a tension to the head component. The equipment has a clamping ring (24), which lies opposite an annular reaction surface (28) which faces the sleeve axially, and which forms an annular clamping gap (27). The associated sleeve end is guided through the ring, and is then turned outwards and back into the gap, so that the tensile stress (34) in the sleeve acts on the ring in order to bring it closer to the reaction surface.

Description

The invention relates to a fluid-operated actuation device, with a rubber-elastic, gas-impermeable casual hose body, the inside with under pressure standing fluid can be acted upon, and with a Hose-like envelope enclosing hose body body that with at least one of its two enveloping bodies end by means of a clamping device on a head part is fixed and the one lattice or net-like structure TUR has so that when the internal pressure is applied to the Hose body with radial expansion a length experiences contraction as the pulling force on the associated Acts headboard.

An actuator of this type works, for example from EP 0 161 750 B1. This has two Headboards with two to be moved relative to each other Components are connectable. Between the headboards stretches out of material with rubber-elastic properties existing tube body that over one of the Head parts can be pressurized with pressurized fluid  is, especially with compressed air. The pressurization results in a radial expansion of the hose body. Around the hose body is a reinforcement in Shape of a tubular or stocking-like envelope, which has a lattice or net-like structure and which with its two enveloping ends also to the head sharing is set. Because of the special structure of the envelope results from the expansion of the Hose body caused radial expansion in one Contraction in length, i.e. a shortening of the axial stretching. This results in an application of tensile force the headboards. Once the fluid comes out of the hose body is released, it returns to its original position back, so that the distance between the two headboards enlarged again.

Actuators of this type can, for example used instead of conventional working cylinders will. They are characterized above all by their low weight and the feasibility of large lengths.

The amount of tractive force that can be transmitted depends largely on the strength of the connection between the envelope and the headboards. Due to the grid or mesh construction offers a large-area fastening with With the help of a clamping device. In the case of EP 0 161 750  are the ends of the enveloping body on an extension of the head part plugged in and there by means of pressed-on clamping sleeves fixed. With high tensile forces there is a risk that the ends of the envelopes slip out of the clamping sleeves.

It is the object of the present invention to provide a loading actuating device of the type mentioned at the beginning create the connection between the envelope and the associated headboard high despite simple construction Can transmit tensile forces.

To solve this problem it is provided that the clamp device has a clamping ring on which the Envelope facing the axial side to form a annular clamping gap an annular headboard Counter surface is opposite, the associated Envelope end passed through the clamping ring closing back around the clamping ring slips and is inserted into the nip, so that the Operation occurring tensile stress of the envelope Clamping ring in the sense of an approach to the counterhold area applied.

This way, one lies with simple technical Means inexpensive to implement clamping device, which, even under strong tensile loads on the enveloping body  safe transmission of traction to the assigned headboard guaranteed. The one put back over the clamping ring Envelope end wraps around the clamping ring and is on finally inserted into the annular clamping gap, see above that the clamping ring under tensile stress from the enveloping body itself is pulled against the counter surface so that at least in the area of the clamping gap Envelope ends. The stronger the pulling forces are, the stronger the clamping forces are, so that practical an automatic adjustment to the respective load case can be done. It's kind of self-locking Deadlock before.

Advantageous developments of the invention are in the Subclaims listed.

It is advisable to adjust the wrap angle with which the Envelope end wraps around the cross section of the clamping ring, provide greater than 180 °, so that high in the clamping gap Clamping forces can occur.

With a very simple design, the actuating device tion, the counter-holding surface can start immediately formed the abutment surface formed the head part. However, an execution promises a better hold shape, in which the counter surface on one of the  Headrest supporting separate counter ring provided is. Is this counter ring from the envelope wrapped around the end, a corresponding Ver increase the clamping effect.

The hose body can in a similar manner to the Headboards must be fixed. The clamp preferably has set up a retaining ring through which the hose passed through the body end and then around the outside Retaining ring is turned back around. Here can stop ring be a separate part with respect to the clamping ring, the the clamping ring on the opposite of the counter surface flanked th axial side. With a cheaper and axially shorter design embodiment, the retaining ring directly from the clamping ring of the clamping device forms, which is thus both for fixation of the enveloping body as well as for fixing the tube body serves.

The present invention is described below with reference to lying drawing explained in more detail. It show in single:

Fig. 1 shows a part of the fluid-operated actuator device according to a first embodiment in the range of a head portion, partly in longitudinal section, in starting position of the constriction device Actuate the,

Fig. 2 shows the actuator of FIG. 1 in a comparable, but reduced Dar position in an operating position and

Fig. 3 shows another embodiment of the fluid-operated actuator in a representation corresponding to FIG. 1.

The fluid-operated actuating device according to the example has a rubber-elastic, gas-impermeable tubular body 1 of any length. For example, it is made of rubber. The tube wall 2 is preferably made thin membrane-like.

The tubular body 1 is enclosed on its outer circumferential surface by an envelope body 3 which is also tubular in shape. The enveloping body 3 forms a type of reinforcement for the tubular body 1 . Overall, it is constructed in the manner of a grid or network, so that one could also speak of a stocking-like structure. In the game, it is composed of intersecting, thread-like thin strand elements 4 which are flexible or limp in the transverse direction, but have a relatively high tensile strength in the longitudinal direction. The strand elements 4 can be arranged so that they run in wesent union in the longitudinal direction 5 of the envelope body 3 , but they alternately loop around or are arranged in the form of alternately opposing helical lines. The resulting lattice or network structure preferably delimits diamond-shaped contoured spaces 6 , in which the opposite corner points are aligned on the one hand in the longitudinal direction 5 and on the other hand in the circumferential direction 7 of the enveloping body 3 .

Textile material, for example yarns, is particularly recommended as the material for the enveloping body 3 or the strand elements 4 . Bendable wires or similar flexible materials, for example also plastic materials, are also conceivable.

The tubular body 1 and the enveloping body 3 practically represent a multiple tube arrangement, in which the tubular body 1 forms an inner tube which is coaxially and tightly enclosed by an outer tube in the form of the enveloping body 3 .

The enveloping body 3 is with its two axial ends, hereinafter referred to as the enveloping body ends 8 , each fixed to a head part 12 of the actuating device. The figures show the actuating device only in the area of one of the head parts 12 . At the opposite end of the enveloping body 3 there is a comparable head part, not shown.

The tubular body 1 extending inside the enveloping body 3 is also rich with its two axial end portions, hereinafter referred to as tubular body ends 9 , fixed to the respectively assigned head part 12 . As a result, the tubular body 1 , the enveloping body 3 and the two head parts 12 form a structural unit which can be used as a fluid-operated actuating device.

In the ready-to-use state, the two head parts 12 are fixed to devices that can be moved relative to one another. For connection to such a device, the head parts 12 can have suitable connecting means 13 , which in the exemplary embodiment are formed by threads. In the thread can, as can be seen in FIG. 2, screw in a bearing eye 14 , for example, on which in turn the device to be actuated can be fixed.

The interior 15 of the hose body 1 communicates with a fluid channel 16 , which enables the supply and / or discharge of a pressurized fluid, preferably compressed air, as required. The fluid channel 16 is in the present case on one of the head parts 12 , through which it passes, whereby it can be connected in a manner known per se to pressure medium lines leading to a valve device, which controls the fluid supply.

In the starting position shown in Figs. 1 and 3 of the tube body 1 is slightly filled with pressure medium, so that it has a sufficient resistant to bending rigidity on. If fluid under pressure is now supplied to the interior 15 , the tube body 1 bulges out according to FIG. 2. At the same time, this leads to a radial expansion of the flexible enveloping body 3 . Due to the special lattice or network structure, the radial expansion is accompanied by a contraction in length of the enveloping body 3 . The length of the diagonals of the diamond-shaped spaces 6 changes, the spaces 6 become shorter in the longitudinal direction 5 and expand in the circumferential direction 7 .

The contraction in length of the enveloping body 3 acts as a tensile force on the head parts 12 fixed to it. These approach each other. The devices attached to the headboards are pulled towards each other.

By venting the interior 15 , the tube body 1 automatically returns to the starting position due to its inherent elasticity, the envelope body 3 also being lengthened again. The head parts 12 now take their original distance again.

In order to be able to transmit high tensile forces to the head parts 12 , the enveloping body 3 is connected to a respective head part 12 with the aid of a preferably configured clamping device 17 . Such a clamping device 17 is preferably assigned to each head part 12 , which is explained in more detail below in connection with the head part 12 shown.

The head part 12 has at the tube assembly 1, 3 axial side facing one to the tube assembly 1, 3 open towards the receiving space 18th It is limited in the embodiment, for example, circumferentially by a sleeve-like holding part 22 which is fixed to a connecting body 13 having the connecting body 23 of the head part 12 . The connector body 23 forms the bottom 19 of the receiving space 18th

The clamping device 17 is taken in the receiving space 18 . It has a clamping ring 24 arranged coaxially in the receiving space 18 , the outer diameter of which is slightly smaller than the inner diameter of the receiving space 18 .

The clamping ring 24 is flanked on the axial side facing the enveloping body 3 by a coaxially arranged counter-holding ring 25 . Both rings 24 , 25 are expediently separate components. An abutment surface 26 flanking the counter-holding ring 25 on the axial side opposite the clamping ring 24 holds the ring arrangement 24 , 25 non-releasably in the receiving space 18th The abutment surface 26 is expediently seen directly on the head part 12 and, for example, is formed by a section of the inner surface of the sleeve-like holding part 22 . The holding section 22 has a spacing from the connecting body 23, preferably a circumferential constriction 29 , the inner surfaces of which face the ring arrangement 24 , 25, represents the abutment surface 26 .

Between the clamping ring 24 and the counter ring 25 he stretches an annular clamping gap 27th Its width depends on the distance between the two rings 24 , 25 . If the two rings 24 , 25 abut one another, the clamping gap is closed. The surface of the counter-holding ring 25 that is in contact with the clamping ring 24 is an annular surface and is referred to below as an annular counter-holding surface 28 .

The sheath body is inserted with its head part 12 facing Hüllkörperende 8 coaxially in the receiving space 18, wherein it lies by both the closer to the opening 32 of the receiving space 18, with retaining ring 25 as well as by the between the pressure ring 25 and the bottom 19 of the receiving space 18 Clamping ring 24 is leads. The envelope body end 8 is then guided radially outwards on all sides and turned back around the clamping ring 24 . In this way, the clamping ring 24 is at least partially wrapped around by a first wrapping section 33 of the enveloping body 3 . Ultimately, the inverted envelope body end 8 is inserted back into the clamping gap 27 so that it comes to lie between the clamping ring 24 and the annular counter-holding surface 28 of the counter-holding ring 25 .

If the enveloping body 3 during operation of the device according to arrow 34 in the opposite direction from the head part 12 is subjected to tension, the first looping section 33 pulls the appropriately limited axially movable clamping ring 24 in the sense of an approach to the counter surface 28 in the direction of the Counter ring 25 . The latter is supported on the counter bearing surface 26 , so that the envelope body end 8 is clamped in the clamping gap 27 . The stronger the tensile force 34 , the stronger the clamping force exerted by the clamping device 17 on the enveloping body end 8 , so that the enveloping body 3 is held securely on the head part 12 even under very high tensile stress.

The counter ring 25 can also be arranged axially limited movable Lich on the head part 12 . However, the gap 31 shown in the drawing between the counter-holding ring 25 and the abutment surface 26 is exaggerated for the sake of clarity. You can in practice make the arrangement so that the two rings 24 , 25 are pressed against each other under a certain bias by the clamping ring 24 from the bottom 19 and the counter ring 25 from the abutment surface 26 is acted upon.

The enveloping body end 8 is preferably passed through the ring opening 35 , which is surrounded radially on the inside by the counter-holding ring 25 . This wall section 36 passed therethrough thus comes to lie between the counter-holding ring 25 and the casing body section 37 passed between the two rings 24 , 25 . When the tensile force 34 is applied, friction occurs in the contact areas, which increases the clamping effect.

While the Hüllkörperende 8 in the embodiment of FIGS. 1 and 2 ends after passing through the annular opening 35, it is in the embodiment of Fig. 3, are provided in the similar in the other components with identical reference numerals, following the Ringöff voltage 35 outside again around the counter-holding ring 25 in the direction of the clamping ring 24 . As a result, there is a second looping section 38 with which the counter-holding ring 25 is now looped. This increases the clamping effect of the clamping device 17 , because the envelope body end 8 is additionally clamped in the above-mentioned gap 31 when tension 34 is applied. This gap 31 thus represents a further clamping gap.

Relative to the parallel to the longitudinal direction 5 he stretching end portion 42 of the casing 3 , which leads coaxially through the opening 32 into the two rings 24 , 25 , the wrap angle is u, over which the first wrap section 33 to the cross section of the Clamping ring 24 extends around, preferably more than 180 °. In the exemplary embodiments, it is in the range of approximately 270 °. This results in a particularly reliable self-locking jamming of the enveloping body end 8 between the clamping ring 24 and the counter-holding surface 28 when the train is moved according to the arrow direction 34 . The annular counter-holding surface 28 is arranged such that the clamping gap 27 formed is located in the area adjoining a wrap angle of 180 °.

As indicated by dash-dotted lines in FIG. 1, the separate counter-holding ring 25 can be omitted in the case of simplified designs. The counter-holding surface 28 can then be formed by an abutment surface 26 'provided directly on the head part 12 '. This can be achieved, for example, by providing on the annular or hollow cylindrical holding part 22 a projection 43 , which preferably extends obliquely radially inward, which engages behind the clamping ring 24 axially on the outside and whose surface facing the clamping ring 24 is the abutment surface 26 which acts as a counter-holding surface 'Forms.

Advantageously, the clamping device 17 is formed such that it serves at the same time as the fixation of the rubber-elastic hose body 1 .

In the embodiment according to FIG. 3, the clamper 17 extended by a retaining ring 44, the axially between the clamping ring 24 and the connecting body 23 is positioned. Its ring diameter is expediently the same as that of the clamping ring 24 and the counter-holding ring 25 , which preferably have the same diameter with one another. For the rest, the cross section of the rings 24 , 25 , 44 is chosen in particular so that there is a continuous, edge-free circumferential line, a circular cross section being appropriate. In this way, damage to the enveloping structure 3 by edges is avoided, in spite of a good clamping effect.

The tubular body 1 is guided into the receiving space 18 in a coaxial orientation with respect to the enveloping body 3 . With an end section 46, it first penetrates the ring opening of the counter-holding surface 28 , then the clamping ring 24 and finally also the retaining ring 44 . At closing, the tube body end 9 is turned back outside around the retaining ring 44 , comparable to the arrangement of the envelope body end 8 with reference to the clamping ring 24 . A third clamping gap 45 is provided axially between the retaining ring 44 and the clamping ring 24 , into which the inverted tube body end 9 is inserted. Thus, acting on the hose body 1 acting tensile forces 34 'act on the retaining ring 44 in the direction of the clamping ring 24 , so that the be sensitive portion in the third clamping gap 45 of the hose body end 9 is clamped. The clamped tubular body section is not in direct contact with the clamping ring 24 , but with the enveloping body end 8 wrapped around the clamping ring 24 .

Preferably, the tubular body end 9 that is turned back is inserted into the ring opening of the clamping ring 24 , so that it comes to lie coaxially between the end sections 42 , 46 of the enveloping body 3 and the tubular body 1 . This can cause the holding force to increase due to friction.

Otherwise, the arrangement will be such that the hose body 1, in particular with its hose body end 9, is in permanent sealing contact with the head part 12 . In this way, escape of fluid from the interior 15 is prevented.

In the embodiment according to FIG. 1 and 2, a sepa rater retaining ring 44 is not for the hose body end 9 is present. Here, the clamping ring 24 takes over the function of the retaining ring 44 , and the tubular body end 9 is looped ver comparable to the enveloping body end 8 around the clamping ring 24 . The tube body end 9 lies on the envelope body end 8 . It does not necessarily have to be inserted into the clamping gap 27 , as can be seen from FIG. 1. Already due to the elasticity of the rubber, however, the hose body end 9 will as a rule automatically nestle tightly against the clamping ring 24 or the wrapping body 8 wrapped around it.

Preferably, the arrangement will be such that the ring arrangement 24 , 25 , 44 including the rings around the looping portions of the enveloping body end 8 and / or the tubular body end 9 are at least slightly axially clamped against one another, on the one hand, by the bottom 19 of the receiving space 18 and on the other hand of the counter bearing surface 26 , 26 'are applied. In the execution example, the degree of preload can be set as desired by selecting the location and the intensity of the lacing 29 as required. The voltage achieved before prevents an automatic loosening of the clamp connection occurs with slack hose body 1 and consequently reduced tensile force 34 . In operation, the clamping force is then expediently increased due to the circumstances described above.

The at least axial clamping also ensures a sufficient sealing contact between the section of the hose body end 9 that wraps around the retaining ring 44 and the bottom 19 of the receiving space 18 .

Claims (17)

1. Fluid-powered actuator, can be charged with a rubber-elastic, gas-impermeable tube body (1), the inside with fluid under pressure, and with a hose body (1) enclosing the hose-like casing body (3) provided with at least one of its two Hüllkörperenden (8 ) is fixed by means of a clamping device ( 17 ) to a head part ( 12 ) and which has a lattice-like or net-like structure, so that when the hose body ( 1 ) is subjected to internal pressure, it experiences a length contraction with radial expansion, which acts as a tensile force ( 34 ) on the assigned head part ( 12 ) acts, characterized in that the clamping device ( 17 ) has a clamping ring ( 24 ) on the axial side facing the enveloping body ( 3 ) to form an annular clamping gap ( 27 ) a head-side annular counter-holding surface ( 28 ) lies opposite, the assigned envelope body end ( 8 ) by d En clamping ring ( 24 ) passed through, then turned back outwards around the clamping ring ( 24 ) and inserted into the clamping gap ( 27 ), so that the tensile stress ( 34 ) of the enveloping body ( 3 ) that occurs during operation, the clamping ring ( 24 ) in the sense an approach to the counter holding surface ( 28 ). 2. Actuating device according to claim 1, characterized in that the envelope body end ( 8 ) through which the annular counter-holding surface ( 28 ) is passed radially inwardly around a closed ring opening ( 35 ). 3. Actuating device according to claim 1 or 2, characterized in that the envelope body end ( 8 ) with an angle of wrap (u) is turned back around the clamping ring ( 24 ), which is more than 180 °. 4. Actuating device according to one of claims 1 to 3, characterized in that the counter-holding surface ( 28 ) is formed by an abutment surface ( 26 ') formed directly on the head part ( 12 ). 5. Actuating device according to one of claims 1 to 3, characterized in that the counter-holding surface is provided on a bracing ring ( 25 ) which is supported on the head part ( 12 ). 6. Actuating device according to claim 5, characterized in that the enveloping body end ( 8 ) through the counter holding ring ( 25 ) is passed through and then turned back outside around the counter holding ring ( 25 ) in the direction of the clamping ring ( 24 ). 7. Actuating device according to claim 5 or 6, characterized in that the counter-holding ring ( 25 ) on the axial side of the clamping ring ( 24 ) is supported on an abutment surface ( 26 ) fixed to the head part. 8. Actuating device according to claim 7, characterized in that the abutment surface ( 26 ) and the counter retaining ring ( 25 ) specify a further clamping gap ( 31 ) which is penetrated by the envelope body end ( 8 ). 9. Actuating device according to one of claims 1 to 8, characterized in that the clamping ring ( 24 ) is arranged to be axially movable to a limited extent on the head part ( 12 ). 10. Actuating device according to one of claims 5 to 9, characterized in that the counter-holding ring ( 25 ) is arranged to be axially movable to a limited extent on the head part ( 12 ). 11. Actuating device according to one of claims 1 to 10, characterized in that the clamping device ( 17 ) is received in a sleeve-like holding part ( 22 ) fixed to the head part. 12. Actuating device according to claim 11, characterized in that the abutment surface ( 26 ) by a circumferential constriction ( 29 ) of the sleeve-like holding part ( 22 ) is formed. 13. Actuating device according to one of claims 1 to 12, characterized in that both enveloping body ends ( 8 ) via a clamping device ( 17 ) are fixed to a head part ( 12 ). 14. Actuating device according to one of claims 1 to 13, characterized in that it is fixed by means of the clamping device (17) the head part fixed to the clamped Hüllkörperende (8) associated with the tube body end (9) by having the clamping device (17) comprises a retaining ring (44), through which the hose body end ( 9 ) is passed and then turned back on the outside around the retaining ring ( 44 ). 15. Actuating device according to claim 14, characterized in that the retaining ring ( 44 ) with respect to the clamping ring ( 24 ) is a separate part which is arranged on the opposite holding surface ( 28 ) opposite the axial side of the clamping ring ( 24 ). 16. Actuating device according to claim 15, characterized in that the turned-up hose body end ( 9 ) is inserted into the ring opening of the clamping ring ( 24 ) and engages there coaxially between the hose body ( 1 ) and the enveloping body ( 3 ). 17. The actuator of claim 14, characterized in that the retaining ring is formed (24) of the clamping ring (24), said turned-back tube section body portion is located on the folded back enveloping body.