FI89947C - FOERFARANDE FOER ATT SPAENNA EN AV SYNTHETIC TRAODAR FRAMSTAELLD VAEVNAD KRING EN CYLINDER OCH SPAENNANORDNING FOER UTFOERANDE AV FOERFARANDET - Google Patents

Abstract

Process for installing, under tension, a cloth (1) around a surface (2): the cloth (1) is pretensioned around the surface and strips (14) are if necessary added to the ends (3) of the cloth (1), and the cloth (1) is joined up and the tension released. The tensioning device (5) has two straps (6) attachable to the ends (3) of the cloth and these are brought together by means of threaded rods (9) on which bolts (12) are screwed. <IMAGE>

Description

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The present invention relates to a method for tightening a fabric made of synthetic yarns around a cylinder and to a tightening device for carrying out the method. especially around the cylinder used in papermaking.

Tightening the tubular fabric around the cylinder has been known, requiring the other end of the cylinder to be free to thread the fabric. This is a time consuming and cumbersome operation that requires specific hardware and a structure adapted to the environment of the cylinder (e.g., a cantilever beam).

Surrounding the cylinders with an open-woven fabric formed in the form of a tube by joining together with at least one wire loops formed at each end of the fabric has also been known.

If the warps and wefts of the fabric are not at right angles to the axis of the cylinder, the fabric can be pulled against it from the edges of the fabric using springs or rings attached to the edges of the cylinder. When using rings, the edges of the fabric are pressed between the rings on each side of the cylinder. They are then pulled away from the edges of the cylinder using screws attached to the rings. The tensile forces on the fabric reduce its diameter and it presses on the cylinder. This is a complex and time consuming operation that requires special hardware at the edges of the cylinder.

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If the warps and wefts of the fabric are at right angles to the axis of the cylinder, it is recommended to use synthetic materials that can be heat-shrinked to attach them to the cylinder.

It is also known to surround the cylinder with an open fabric made of interconnected plastic spirals and to close it by gripping the spirals at both ends together and locking them with wire. These spirals are made of heat shrinkable plastic. The fabric is attached to the cylinder by heat treatment. Hot air, steam or hot water is used to heat shrink a woven or spiraled plastic fabric.

This technique is also difficult to implement because it requires a heat source. In addition, shrinkage is not always sufficient to properly hold the tissue in the cylinder.

In addition, non-shrinking or low-shrinkage yarns cannot be used.

The method of the present invention for tightening a fabric made of synthetic yarns to the surrounding surface is easier to perform than the above, and is characterized by the use of an open fabric terminating at two ends in the connecting means and provided at these ends with fastening elements at regular intervals. , where the fabric is shorter than the surrounding surface, the fabric is wound on the surrounding surface to form a sheath, the tensioning device applies strong tension to the fastening elements to bring the two ends closer together along their entire length, one or more strips of synthetic yarns of the same length as , these strips having two edges provided with loops which

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39947 is interleaved in the loops of the ends or adjacent strips to form channels into which the wires are inserted, the number of strips being added just to bring the sheath to substantially the desired tension, and to allow the two sheath end loops to be joined together to form a locking channel; remove the clamping device and the fastening elements.

An embodiment of the method according to the invention is characterized in that an open fabric made of synthetic yarns is used, which ends in loops or spirals at two ends, the fabric having at least one end several narrow strips of synthetic yarns of the same length as the width of the fabric, and in which these strips have loops or consisting of spirals intertwined with loops or spirals of adjacent strips and connected by wires, each end provided with fastening elements fastened at regular intervals along the length of the ends, twisting this fabric around the surface, pulling tightly to the fastening elements close to the fastening elements, removing one or more strips from one end of the fabric so that the length of the fabric becomes just sufficient to surround the surface substantially as desired; With external tension, the tissue terminating loops or spirals are gripped together to form a locking channel, the wire is inserted into the locking channel, and the fastening elements and the tightening device are removed.

Another embodiment of the method according to the invention is characterized in that an open fabric made of synthetic yarns terminating in loops at two ends is wound, the fabric is wound on a surrounding surface, the two ends of the fabric spaced apart, tapering from one side of the fabric to the other next to the two ends, in order to bring them closer to the desired tension, a strip of synthetic yarns of greater length than the width of the fabric and two edges provided with loops approaching each other in the same way as the ends of the sheath at angle a is moved between the ends of the sheath; so that the strip completely fills the space between the ends, connect the loops of the ends to the loops of the strip to form two locking channels, insert the wires into the locking channels, release an tension at the ends of the tissue and then cut the strip to the width of the sheath.

The method according to this second embodiment is particularly simple to perform and requires only one strip, regardless of the width of the cylinder to be coated.

The main use of the method of the invention relates to the coating of a cylinder, but it can also be used to tighten the fabric around a surface which may consist of a ver-surface of a group of parallel cylinders (33) or elements.

In order to carry out the method according to the invention, it is preferable to use a device comprising two belts with a longitudinal rigid rod, between which transverse screw rods are mounted, the rods being provided with nuts by tightening the longitudinal rods converging and the belts being arranged so that they can be fastened parallel with the parent lines near the ends of the tissue.

This device is particularly easy to use, and in particular it is simple to place and remove.

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The invention will be better understood from the following detailed description, taken in conjunction with the accompanying drawings:

Figures 1, 2 and 3 show the placement of tissue around a cylinder according to the invention;

Figures 4 and 5 show tissue placement according to a modification of the invention;

Figure 6 shows another variant of the method according to the invention;

Figure 7 shows a fabric arranged around a plurality of cylinders; and

Figure 8 shows another modification of the method according to the invention.

The method according to the invention for placing a fabric 1 made of synthetic yarns around a cylinder 2 comprises the following steps (see Figure 1). Take fabric 1, which consists of e.g. a woven body terminating at two ends 3 in sets of loops 4; the manufacturer has sewn the edges 13 of the belts 6 to the ends 3 of the fabric 1 parallel to them, i.e. parallel to the axis of the cylinder.

The user wraps the body around the cylinder 2 to form a jacket, whereby the length of the body 1 is smaller than the circumference of the cylinder but its width is the same as the width of the cylinder 2.

A tensioning device 5 (see also Figure 2) is used, which is fitted to two flexible belt loops 6 with a width equal to or greater than the length of the cylinder. For this purpose, two rigid metal rods 7 are placed in the loops 6 of the O 9 947s. A set of centering pins 8 is attached to these rods 7. Threaded rods 9 perpendicular to the rods 7 in the loops 6 are attached at one end to the centering pins of the rigid rod 7 and extend at one end 10 from a hole 11 formed in the centering pins 8 of the second rod 7. These second ends 10 are provided with nuts 12.

The nuts 12 are tightened so that the two rigid rods 7 approach each other. When the piece 1 has been stretched to a tension deemed sufficient (preferably more than 50 kg / m 2), one or more strips 14 of synthetic yarn of the same length as the width of the cylinder 2 are introduced next to it, each edge being provided with loops 15. The strips 14 are joined together interleaving the loops of the edges between each other and inserting the wire 16 into the channels 17 thus formed, and in the same way at the two ends 3 (see Fig. 3). The strips 14 are used in an amount sufficient to fill the gap between the two ends 3 of the tensioned fabric. If this gap is zero, the strips 14 are not needed at all.

The nuts 12 of the threaded rods 9 are unscrewed to remove the tension provided by the device 5, after which the belts 6 are removed. The fabric 1 is thus tightened around the cylinder 2.

According to a variant, instead of a fabric with a length shorter than the circumference of the cylinder 2, a fabric 1 with a length slightly longer than this circumference can be used.

Such a fabric supplied by the manufacturer already has two belt loops 6 at each end of the fabric. In the same way, two-part belts 6 ', 6 "can be used, which are connected by locking means 34 (sliding rod fastening, see Fig. 8). Only part 6' at the ends of the fabric is fastened by 79947 and the parts 6" are fastened by the user to parts 6 '. After installation, the tightening device 5 can be removed and used to install another fabric.

In the example of Figure 4, the fabric 1 consists of strips 20 of spirals 22 connected by yarns 21.

A tightening device 5 similar to that in the example of Fig. 1 is used. However, the edge opposite the rigid rod of the belt loops 6 is provided with rigid loops 23 which pass partly through the spirals 22 at each end of the fabric 1 along baseline lines parallel to the axis of the cylinder 2. The manufacturer has fastened these loops 23 to the spirals 20 with a piano wire 24. These rigid loops 23 may be formed together with the warp yarns of the belt or spirals tightened with the belt wires or metal hooks attached to its edges. The loops 23 are then fastened to the straps 6.

The nuts 12 of the screw rods 9 are then tightened so that these rigid rods approach each other until the desired tightening is achieved.

The excess length of the fabric 1 is removed by removing a sufficient number of strips 20 of the coils 22. The tension of the fabric length between the two mother lines is kept just enough to close the fabric 1 by gripping the ends of the coils together to form a locking channel 26 (see Figure 5).

The nuts 12 of the threaded rods 9 are then unscrewed to remove tension and the loops 6 are removed by removing the piano threads 24.

In one embodiment of the method according to the invention shown in Fig. 6, a fabric 1 is used, the two ends of which form an acute angle with each other when the fabric 1 made of synthetic yarns is wound around a cylinder 2.

These ends are provided with loops 28. Using the tightening device described above (not shown in Figure 6), the fabric 1 is pre-tightened around the cylinder 2 to the desired tension. A narrow strip 29 is then pushed next to it, the two edges 30 of which are provided with loops 31 and which form the same angle as the two ends 27 of the fabric 1.

The strip 29 is moved until it occupies exactly the space between the two ends 27. The loops 31 of the strip 29 are then gripped into the loops 28 of the ends 27 to form two locking channels into which the locking wires 32 are inserted.

The tensioning device is removed and the strip is cut to the width of the cylinder.

These different methods for placing the fabric 1 can likewise be used for placing the fabric around a surface defined, for example, by a plurality of cylinders 66 with parallel axes, as shown in Fig. 7.

In the previous description, the loops at the ends of the fabric or at the edges of the spacer strips can be replaced by spirals, hooks or, more generally, by all the connecting means which, when gripped together, form a locking channel into which the wire can be inserted.

Of particular interest in the placement methods described is that the manufacturer has already fastened the fastening elements (6, 23, 6 ') parallel to the ends of the fabric, and the user only needs to place the tightening device (5) in place, which is easy to do and remove or insert the straps. also easy to implement.

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Claims (7)

9 39947 A method for tightening a fabric (1) made of synthetic yarns on a surrounding surface (2), characterized in that an open fabric (1) is used, which terminates in loops (4) at two ends (3) and which has at these ends (3) ) provided with fastening elements (6) fixed at regular intervals along the length of the ends (3), the fabric (1) being shorter than the surrounding surface (2), the fabric being wound on the surrounding surface to form a sheath, the tensioning device (5) applying strong tension to the fastening elements (5) 6) in order to bring the two ends (3) closer together along their entire length, one or more narrow strips (14) made of synthetic yarns of the same length as the width of the fabric (1) are added to the ends (3) of the fabric (1), whereby these strips (14) has two edges provided with loops (15) interlaced with the loops (4) of the ends (3) or adjacent a number of strips (14) added to the loops (15) of the strip (14) to form channels (17) into which the wires (16) are inserted, just enough to bring the sheath to substantially the desired tension, and to allow the two sets of loops (15, 4) terminating the sheath to be joined; together to form a locking channel (17) into which the wire (16) is inserted into the locking channel (17), and the tightening device (5) and the fastening elements (6) are removed. A method of tightening a fabric (1) made of synthetic yarns on a surrounding surface, characterized in that an open fabric (1) is used, which ends at two ends (18) in loops or spirals (21) and is provided at these ends with fastening elements fastened at regular intervals along the length of the baselines parallel to the ends (18), the fabric (1) having at least one end (18) a plurality of narrow strips (20) of synthetic yarns having a length 10 89947 equal to the width of the fabric (1), and wherein these strips (20) are loops or are formed of spirals (22) interleaved with loops or spirals of adjacent strips (20) and connected by wires (21), this fabric (1) is wound around the surface (2) to form a sheath, pulled by a tensioning device (5) ) strongly fastening elements (6) to the baselines to which the fastening element t is attached, in order to approximate each other, one or more strips (20) are detached from one end of the fabric (1) so that the length of the fabric becomes just enough to surround the surface (2) with substantially the desired tension, the fabric terminating loops or spirals 26), insert the wire (21) into the locking channel (26), and remove the fastening elements and the tightening device (5). A method of tightening a fabric (1) on a surrounding surface (2), characterized in that an open fabric (1) terminating in loops (28) at two ends (27) is used, the fabric is wound on the surrounding surface (2) to form a sheath, the fabric (1) ) with the two ends (27) spaced apart, tapering from one side of the sheath (1) to the other at an angle α, pulled vigorously next to the two ends (27) to bring them closer to the desired tension, a strip of synthetic yarn (29) , the length of which is greater than the width of the fabric and the two edges (30) of which are provided with loops (31) approaching each other in the same way as the ends of the sheath (1) at an angle α, move the strip (29) between the ends (27) of the sheath (1) so that the strip completely fills the space between the ends (27), the loops (28) of the ends (27) are connected to the loops (31) of the strip (29) by two locked to form the channel, insert the wires (32) into the locking channels, release the tension from the ends of the fabric (27) and then cut the strip (29) to the width of the sheath (1). li 11 0 9 947 Method according to one of the preceding claims, characterized in that the surrounding surface is a cylinder (2). Method according to one of Claims 1 to 3, characterized in that the surrounding surface is an array of cylinders (33) or elements which are parallel to one another. Tensioning device (5) for carrying out a method according to one of the preceding claims, characterized in that it comprises two belts (6) with a longitudinal rigid rod (7), between which transverse screw rods (9) are mounted, the screw rods (9) being provided with nuts ( 12), by tightening the longitudinal rods (7) approaching each other, and the straps are arranged so that they can be temporarily attached to the baselines of the fabric near its ends (3, 18, 27) parallel to the longitudinal rods (7). Tensioning device according to claim 6, characterized in that each belt (6) comprises two parts (6 ', 6 ") which can be locked together by locking means (34), whereby the first part (6') can be fastened to the fabric and the second part (6) 6 ") is equipped with a rigid rod (7). 12 9 947