DE8004622U1 - CLAMPING DEVICE - Google Patents

Description

The invention relates to a device for tensioning sleeves or rolls of strip-shaped material.

As devices for tensioning sleeves or rollers in the form of a tape Material pneumatically operated winding shafts are known in which a supporting tube is provided with elongated holes is, in which clamping jaws are arranged to be radially movable, from the inside via a coaxially arranged hose be pushed out when pressurized. The clamping jaws can be placed on pipe segments for even load distribution be attached.

A disadvantage of this known device is that the force is only transmitted in the area of the clamping jaws. Soft sleeves are polygonally deformed by this type of clamping. There is a risk of damaging the Sleeves in the area of the clamping jaws. By slotting the support tube, its load-bearing capacity is also reduced. This reduction must be counteracted by larger material cross-sections, but one has the disadvantage of a must accept higher weight. However, since the winding shafts mostly belong to the manually operated area of a system, this leads to a higher burden on the operating personnel. Another disadvantage is the variable moment of inertia. In the case of bodies of revolution, this leads to vibrations which occur during the machining or production of strip-shaped material in the form of harmful tension fluctuations.

There are also pneumatically operated winding shafts with axis ■ known parallel economy slats. Again, there is a polygonal Deformation of the clamped sleeve takes place. These winding shafts also show a variable during the rotational movement Moment of inertia. These winding shafts are made of solid material or very thick-walled tubes, see above that their weight is high.

In the two devices described, the direction of loading of the clamping lamellae or the clamping jaws changes constantly as the winding shaft rotates. The elements V on top are affected by the weight of the roller with a pure compressive force; burdened. In a horizontal position, the elements have to transmit shear forces and, directed downwards, they support the direction of action of the roll's own weight. These loads are also superimposed by shear stress from the belt tension. Since the effective areas of the force application in _; generally do not exceed 10% of the inner surface of a sleeve; the transmitted forces are not sufficient to keep the winding shaft exactly in the center of the roll of the strip-shaped material. This so-called "floating" the role is often the \ cause of winding defects.

When building a lap, a hard core is very important to avoid lap failures Star formation and the so-called telescoping of the winding process take place at the beginning with a relatively high tensile force

got to. The clamping elements of the winding shaft must then be sufficient Transfer force to prevent the core from yielding during winding.

The present invention is based on the object eii To create a clamping device for clamping sleeves or rolls of strip-shaped material which do not have these disadvantages. Their weight should be as low as possible for better manageability. The moment of inertia should be increased during the rotation do not change. The so-called "swimming" of the roll on the winding shaft should be reliably avoided. It should a hard winding core can be formed by placing the core under high compressive stress from the inside, which Attack on the largest possible area inside the sleeve. These and other advantages are achieved by the inventive Device reached.

The clamping device according to the invention is characterized in that it consists of a load-bearing cylinder to the helically a pressure-tight, closable hose is wound, which when internal pressure is applied its cross-section enlarged, with at least one end of the hose being connectable to a pressure supply.

The stable cylinder preferably consists of a thin-walled one drawn precision steel tube or a drawn aluminum tube. There is no machining work on the cylinder

jacket required, which means that the particularly resistant surface of the drawn tube is retained. One can go to Manufacture of the device use commercially available drawn tubes without, as in the prior art, these tubes in to have to work in a special way. In particular, it is not necessary to have recesses in the outer surface of these tubes or to mill slots, whereby the. uniform load-bearing capacity of the pipe is influenced. According to the invention The load-bearing cylinder used has a closed lateral surface in its clamping area. This achieves that when the cylinder rotates, no vibrations occur as a result of the uneven elasticity of the cylinder jacket. A particular advantage of the stable cylinder is therefore its inexpensive availability and in the uniformity of its load-bearing properties.

In the case of cylinders with a larger diameter, tenons can be provided on both sides for easier storage and clamping small diameter and fixed in the usual way, e.g. by using support disks.

The end of the stable cylinder is placed in the winding device clamped. The clamping can be force-locked via jaw chucks or form-locked, e.g. by polygonal tenons / take place in axially movable clamping heads or in hinged bearings. When using tapered pins you have the Advantage of exact centering.

In the simplest case, the device according to the invention is helical around the load-bearing cylinder wound a hose. One end of the hose is sealed pressure-tight, while the other end of the hose can be connected to a pressure feed. So you can, for example wisely place a valve at this end of the hose, as is used e.g. on car tires. It is natural also possible to design both ends of the hose to be connectable to a pressure feed and to transfer the pressure medium, e.g. Compressed air to be supplied from both sides.

To tension a sleeve on the device according to the invention, pressure is applied to the hose, as a result of which its cross-section increases and creates a positive connection with the sleeve or roller pushed over. The pressurization can be carried out once via the above-described, preferably designed as a non-return valve Valve. It is of course also possible to use the pressure feed device during the entire time of the clamping to leave connected. As a result, the pressure is maintained even if small leaks occur.

The hose can be wound helically around the load-bearing cylinder in a simple manner. However, it is also possible to wind the hose on the cylinder with a certain pre-tension. The hose is then also in pressure-relieved phase fixed firmly on the jacket of the load-bearing cylinder. It is of course also possible to use the

Glue the hose to the stable cylinder when wrapping it in order to fix it on it. This can be done using 1

an adhesive or a double-sided adhesive tape. S.

However, it makes sense to use an adhesive that has a: · $

Detachment of the hose allows, if after a longer %

Use or if there is a leak to replace the cylinder / ;,

must be handled. _} ;;

The cylinder can accommodate the hose and its
better fixation have helically arranged grooves Γ in which the hose is embedded.

Instead of one hose, a plurality of hoses s | be wound helically on the cylinder. ■; The hoses can be in the form of a multi-thread
Helical line are wound, with each of the hoses being separately or jointly connectable to a pressure supply
is. However, it is also possible to wind the hoses one behind the other, ie in sections, onto the load-bearing cylinder in a helical manner. If the same pressure is applied to these different hoses, a uniform clamping area is formed over the entire cylinder. Beauf- Jj 'one beats however the individual from the winding up of each one;' Individual hose formed sections with different pressure, you can generate sections of different clamping force on the load-bearing cylinder. For example, it is possible to apply the clamping force at the two ends of the pushed-on sleeve higher than in the middle area of the sleeve.

place. Of course, the reverse is also possible, i.e. setting a higher clamping force in the middle the clamping device possible. This can be of particular importance Be interested in winding up material that is sensitive to draft.

Tubes with or without inherent elasticity can be used as hoses. In general, however, hoses are included a certain inherent elasticity preferred in order to achieve that when the pressure is relieved, the hoses at least partially return to their original shape and ensure easy removal of the sleeve or roller from the clamping device is.

The hose used can have a round cross section. However, it is also possible to use hoses with rectangular] To use cross-section, in which case the walls can preferably have a different flexibility. the Hoses should, in order to bring about a secure bracing, with different flexibility, especially in in the radial direction more than in the axial direction. The tubes can also consist of several chambers. To the Better fixation of the hose on the stable cylinder: you can also use hoses with a semicircular cross-section. When using a smooth cylinder, a hose with a semicircular cross-section with its straight boundary surface is created wound on the outer surface. He knows

Cylinder, however, has a helical groove, It can be advantageous to wind up the hose with a semicircular cross-section so that the rounding of the hose in the groove of the cylinder lies. This results in an approximately smooth, cylindrical outer shape of the clamping device achieved. It is also possible to use hoses whose side walls have bellows-like folds, so that in the Pressurization facilitates the expansion of the hose in the radial direction.

It is advantageous to use hoses that have a wear-resistant fabric jacket on the outside and a tight film hose on the inside have that is insensitive to kinking. For example, hoses are commercially available that with a total thickness of about 1 mm a width of 20 to 30 mm. The load capacity of such a hose is about 10 bar overpressure.

A rough calculation shows that with the invention Device achievable clamping forces in the winding shafts known from the prior art not to are to be achieved. For example, a 3 "(76 mm) inside diameter sleeve with a contact ratio of 80% with a A compressive force of 190,000 N / m length is applied.

Due to the small cross-section, the volume in the hose is small. This allows for quick filling and Vent the hose or hoses.

When using the device according to the invention, the winding tubes are spared when they are stretched, as in contrast to the prior art do not attack rigid clamping elements on their inner surface, but rather the flexible ones The hose wound onto the support cylinder and pressurized with pressure medium evenly over the entire surface, or at least carries over a large part of the area.

Although the device according to the invention is already in the The form described so far is fully usable and fulfills the tasks set on it, but it has proven to be useful proved to additionally coat the hose-wrapped, load-bearing cylinder, with this coating either the function of a wearing layer or the function of a further equalization and equalization of the pressure or has both functions equally. In addition, the sheathing, especially if it is pretensioned to a certain degree is applied, exert a restoring effect when the device is depressurized. This will make the print media accelerated out of the hose or hoses when the pressure is released.

This casing must be able to move radially in relation to the load-bearing cylinder. You can in particular by an elastic Tube, for example a rubber tube, be formed, which is pushed onto the wrapped cylinder coaxially and optionally has shrunk.

• · ■ I - .1.1 ,,

It is also possible to use a stretchable fabric cover or a plastic netζ.

Furthermore, it is also possible to use a pipe that may be slotted longitudinally. The elastic change in volume is achieved here by the longitudinal slot.

Another embodiment of the invention of the casing is formed by a plurality of overlapping lamellae, which when pressure is applied to the wrapped hose remain tangential to each other with the formation of a large cylinder jacket circumference.

A particularly simple type of sheathing consists in the arrangement of a plurality of rods in the axial direction. These rods can be pushed into corresponding holding devices, for example the collar of a cup wheel, at the two end regions of the load-bearing cylinder. These rods can, for example, be made of hard rubber, plastic or, in the simplest case, made of wood and optionally point-like, for example by means of ■; Brackets, or in some areas, for example by gluing, can be connected to one another. This provides a longitudinally slotted £ is: tubular outer jacket produced which can be easily replaced if mechanical damage.

It is also possible to use elastic, band-shaped material around the with a hose:

■ /

to wrap provided cylinder. To avoid crossing points, the band-shaped, elastic material is also offset arranged layers preferably in the same slope as the pressurizable wound on the cylinder Wrapped hose. It is also possible to have several layers of the strip-shaped material and then optionally in a cross shape to wind up.

The device according to the invention is shown in FIGS. 1-14.

1 shows a first embodiment in side view with cut opening and in rest position, i.e. before clamping,

FIG. 2 shows the device according to FIG. 1 in the working position with a spanned roll of strip-shaped material. FIG. 3 shows a further embodiment of the device according to the invention, encased, in a side view with a broken section in rest position, i.e. before tensioning. Fig. 4 shows the device according to FIG. 3 in pressurized form Condition with a stretched roll of tape-shaped material. 5 to 9 show the devices according to the invention special designs of the sheathing by sheet metal lamellas is here

Fig. 5 is a cross section in plane V-V of Fig. 6, Fig. 6 is a partial longitudinal section in plane VI-VI of Fig. 5, 7 is a perspective showing an overlap detail - stepped overlap - showing,

• · · t · t

t · · ■ t

• · · I

- 15 -

Fig. 8 like Fig. 7, but showing the edge flange recess, Fig. 9 like Fig. 8, but showing a smooth overlap on the outside.

FIGS. 10-14 show further embodiments of the sheathing by wooden rods, it is here

10 is a longitudinal section,

11 is a partial side view,

FIG. 12 shows a cross section in plane XII-XII of FIG. 11, FIG. 13 shows a part of the casing in the working position, 14 shows a cross-section through an embodiment in which the wooden rods of rectangular cross-section on an elastic Carrier hose are attached.

In Fig. 1 is an embodiment of the invention Device shown in a view with a cutaway view. An end plate 2 is welded into the central cylinder 1. In the end plate 2, a check valve 3 is fastened with a nut 4. At the end of the cylinder facing the inside of the cylinder Non-return valve 3, the hose 5 is attached, which exits through an opening 15 from the cylinder 1 and then is wound helically around the cylinder 1. At the right end the tube 5 is closed, e.g., like Shown here by overlap 16 and tape 17. The The device is inserted into the winding core 6 of the strip-shaped material. Hose 5 is still in the rest position, i.e. it is still flat, which means that the diameter 20 of the hose jacket is smaller than the diameter 21 of the winding core and thus easy insertion is possible.

In Fig. 2 the device is shown in the pressurized state. The hose 5 is through a pressure medium, e.g. compressed air, changed in its cross-section in such a way that the winding core 6, on the helically the band-shaped material is wound, centered, form-fitting and fixed to the cylinder 1 without play. The hose 5 is on his End, here for example by a claw 22, closed inside the cylinder 1 after the end of the hose by a Opening 23 was introduced.

Another preferred embodiment of the invention Device is shown in Fig. 3 in longitudinal section, over the Hose 5 is drawn a rubber-elastic hose 8 coaxially to the cylinder 1. This hose 8 preferably has so much pretension that it generates a restoring force with respect to the expanded hose 5 of variable cross-section, so that after the pressure has been relieved, the cross-section of the clamping device is so reduced that the previously clamped one Sleeve or roll can now easily be pulled off laterally. i.e. the diameter 20 'is smaller than the diameter 21 '.

FIG. 4 shows the device according to FIG. 3 in the pressurized state.

Fig. 5 shows a further embodiment of the invention Device in cross section. Load on cylinder 1

you can find the hose 5 $ wound in a helical line

Above the tube 5 and completely covering it are ^

Lamellae 9 arranged, which ft when pressurized

of the hose 5 against each other and thus the i |:

Increase the outside diameter of the clamping device. He Ii

the lamellas 9 extend in the axial direction over the:

entire clamping range. ί

In Fig. 6, the attachment of the lamella ends is shown. V A ring 30 overlaps with extension 31 the flanges 32 of the
Lamellas 9. The flanges 32 are cranked inwards, see above
that the outer diameter 33 of the ring 30 is smaller than that
Outer diameter 34 of the lamellae may be at rest. yy | The ring 30 is arranged on both sides of the cylinder 1 and is fastened, for example, by pins 35.

Fig. 7 shows the simple overlap on slats 9 and the
Flanges 32. There are practically negligibly small steps 36, 37.

Fig. 8 shows that the Ϊ step 37 is eliminated by recess 38 at the end of the lamella. The flanges 32 thus have exact $ circular shape.

Fig. 9 also shows the rear end 39 of the lamella 9 according to
cranked on the inside so that a stepless, cylindrical clamping surface is created.

I t

Figs. 10 to 13 show a further embodiment of the

Sheathing of the device according to the invention. It is in turn on the cylinder 1 in a

f Helically wound hose 5 (Fig. 10). Above that

Tube 5 are rod-shaped segments 10 (Fig. 12).

jl, which is when pressure is applied to the hose 5

Move if radially to cylinder 1 and apply the clamping force to the

Transfer inside of the sleeve or the winding core 6.

Fig. 10 shows a longitudinal section through the device. It can be seen that the ends of the strips 10 are movably mounted on the field side in the cup disk 30, wherein the cup disks 30 are attached to the cylinder 1 by pins 35.

11 and 13 show the possible point connections, for example 41 of the strips 10 with one another.

14 shows strips 45 of rectangular cross-section, which rest on an elastic support tube 46 as a sheathing. The result is an approximately round clamping cylinder.

Claims (12)

Protection claims 1. Device for tensioning sleeves or rolls in the form of a tape Material, characterized in that it consists of a load-bearing cylinder around which it is helical a pressure-tight, closable hose is wound, which its when internal pressure is applied Cross-section enlarged, at least one end of the hose being connectable to a pressure feed. 2. Apparatus according to claim 1 _r, characterized in that a plurality of hoses is wound one behind the other or in a multiple helical line around the cylinder. 3. Apparatus according to claim 1 or 2, characterized in that the expansion of the hose when pressurized, in relation to the cylinder, is greater in the radial direction than in the axial direction. 4. Device according to one or more of claims 1 to, characterized in that the hose is elastic. 5. Apparatus according to claim 4, characterized in that the hose is at least approximated when the pressure is relieved returns to its original shape. 6. Device according to one or more of the preceding Claims, characterized in that the cylinder has grooves for receiving the hose or hoses. 7. Device according to one or more of the preceding claims, characterized in that the hose wrapped Cylinder has a radially movable casing. 8. Apparatus according to claim 7, characterized in that the casing is formed by an elastic tube. 9. Apparatus according to claim 7, characterized in that the casing by one, optionally multiple, longitudinally slotted Tube is formed. 10. The device according to claim 7, characterized in that the casing is formed by overlapping lamellae is. 11. The device according to claim 7, characterized in that the casing is formed by a plurality of rods arranged in the axial direction. 12. Apparatus according to claim 7, characterized in that the sheath is formed from a winding of a band-shaped elastic material.