FI107725B - Method and apparatus for reel replacement in a reel - Google Patents

Description

107725

Method and apparatus for reel replacement in a reel

The present invention relates to a method of reeling a reel having a reeling cylinder, a roll of a web formed from a web about a reel 5 through a reel roll, and an empty reel introduced for exchange, the web passing a distance on the surface of the empty reel roll. The invention also relates to a device in a reel for replacing a reel for securely clamping the end of a truncated web to the surface of an empty reel 10 after cutting the web, the device comprising a reeling cylinder, a filling roll formed from the web around the reel and an empty reel.

For example, in a paper roll continuous-acting roller known as the Pope reel, the new reel roll is often replaced with a full reel so that it is accelerated substantially to a web speed and lowered or otherwise secured to the reel drum. The roll change can be carried out e.g. the machine reel is removed from the 20 reel cylinders, its speed drops, and a bag is formed between the reel cylinder and the full Tam cage, which is blown around an empty reel roll, thereby tearing the web. Frequent web cutting with a full-width impact blade cutter is also often used to reduce wastage of paper and minimize the changeover process without any tear-free material. After cutting ·: ··: the paper web is guided around a new reel reel.

U.S. Patent No. 5,360,179 describes a roller change in a pop-up reel wherein an empty roll is lowered into a reeling cylinder and a widening strip separated by water jets before the reeling cylinder is blown around the empty roll. Other means of exchange are also described in this • • publication. U.S. Patent No. 3743199 discloses a roll change in which a paper web is rotated around a new reel reel by means of a vacuum applied to the reel reel, for which the roll casing has been torn.

• · • · ·

Current paper machines are so fast that if the paper head is not immediately rewound on the new 2 107725 empty reel reel, the reel bottom may become uneven and easily create hundreds of meters, even a few kilometers of wasted paper.

The solution according to the invention provides a method and a device for changing the paper web from a full reel to a blank so that no waste paper is generated. The method according to the invention is characterized in that the end of the truncated web is guided around the surface of the interchangeable empty roll by means of air jets blown from the inside of the roll.

The invention is based on the so-called phys. Coanda effect, where an air jet from an opening that opens to the surface, with a suitable aperture and surface transition structure, follows this surface. When the air jet is directed into the space between the roll surface of the roll and the paper web, it causes a vacuum in this space, which causes the paper web to remain close to the surface of the roll.

According to the invention, an air jet is applied to the grooves made on the surface of the empty reel roll introduced into the web in connection with the roll change, which secures the new end of the paper web to the surface of the reel roll. In this way, the paper web wrapped around the cat-20 is immediately wound on an empty reel roll and does not produce discarded paper. The method of the invention can be used to replace a reel reel regardless of the cutting method, but is particularly well suited to a replacement method using: a full-width cutting device.

*: · 25 ·: ··: The device according to the invention, in turn, is characterized in that: ·: ··: the reel roll has a built-in air duct which can be connected to a source of compressed air, thereby opening openings or gaps in the roll casing air jets from the slots are directed in the direction of rotation of the roll along the surface of the jacket.

• · · • ·

The method of the invention and the device implementing the method are defined in more detail in the appended claims. In the following, the invention will be explained in detail with reference to the following figures, where: · · · · · * 35 Figure 1 shows a side view of the reel, illustrated only by: · · · · · * essential parts of the invention, 3 107725 Fig. 2 shows a sectional view of an empty reel reel, showing details of the invention, Fig. 3 shows a front reel of an empty reel, and Fig. 4 schematically shows apparatus for controlling operation of the method of the invention.

Fig. 1 is a side elevational view of a reel of a paper machine or paper finisher having a finished paper roll R formed around a tampon roller 2. hold load. The loading is achieved by means of a loading mechanism acting on both ends of the reel roll 2, not shown in more detail.

Fig. 1 illustrates a situation in which the inflatable roller R is moved along the ends of the reel roller 2 supporting the winding rails 3 further away from the roller cylinder 1. An empty reel roll 2a, of course similar to the previous reel roller 2, is brought into an interchangeable position The paper web W passes over the reeling cylinder 1, through the nip N between the reeling cylinder 1 and the reel roll 2a, and after the nip 25 N, below the empty reel roll 2a for some distance along the surface of the empty reel 2a. Below this roll 2a, there is a paper-cutting cutter 4, which may be a cutting machine, which in itself is known in the art, by means of a blade located in the direction of the full-width cut-off web W. The cutting device 4 is located near the point where the paper web is released from the surface of the roll 2a. The cutting device 4 cuts the ... paper web and the air blowing device according to the invention, which will be described later, built into the roll 2a, secures the end of the paper web W cut off by the cutting device 4 to the roll 2a, and start.

35

Fig. 2 is a sectional view of a sheath 5 of roll 2a showing an air blowing system according to the invention. Roll 2a is known to be hollow. A narrow air distribution channel 7 extends from the end of the roll 2a to the inside of the sheath 5 of roll roll 2a 107725 4. The coating on the roll surface is provided with circumferential grooves 6 around the roll shell 5. A bore 8 is drilled through the jacket 5 and is plugged with a plug 10 before plating. Further, the bottom 6 of the groove 6 has been drilled into the diaper 5 in an oblique position opposite its radius 5, allowing air flow to pass through the diaphragm 7 through the holes 8 and 9 into the groove 6. Thus, openings or slots for air jets open to the bottom of the grooves. In the air distribution channel 7, air is led through the roll axis by means of known elements, using a compressor or pneumatic network without a flow control device such as a valve. The air flows from the holes 9 pass through the grooves 6 and discharge from the grooves 6 under the new end of the web at a sufficiently high speed to maintain the required vacuum.

Fig. 3 is a front view of a portion of the roll 2a. It is advantageous to make grooves 6 on the surface of the roll shell 5 at regular intervals d, e.g., about 50 to 250 mm, preferably about 100 to 200 mm. At the bottom of the grooves 6 through the wall of the sheath 5 are drilled holes 8 having a diameter of about 3 mm and also holes 9 which are also about 3 mm in diameter and are at an angle of a maximum of 30 ° with the tangent of the roll sheath 5. It is advantageous for the invention 20 that the angle α is as small as possible, i.e. the holes 9 are as close as possible to the tangential direction. The outer end of the shell 8 of the hole 8 is blocked by a stopper 10 and the air flow from inside the roll has to pass through the channel 7 through the hole 8 and the hole 9 into the groove 6. The roll * ·· **: the drilled holes 8 and in the parallel row, whereby the mouth openings of the holes 9 which open to the bottom of the grooves 6 of the jacket 5 thus form a straight row. Because of the small volume and narrowness of the manifold ·: ··: 7, the holes and openings: T: are in one straight row, but if the manifold is wider, they can also be located at different points, so that they are in a short sector. The structure shown in Fig. 3 is advantageous for machining, but in principle it is possible to drill one hole 9 passing through the entire casing and ending in the distribution channel 7 at an angle α j.

·· ♦ • ·: ··: Figure 4 shows the devices that according to one embodiment ·: ··: 35 are required for the air jet to be discharged and the web to be cut oi-.v. temporarily so that the air jet from the holes 9 begins to discharge into the groove 6 some time before the cut-off. In Fig. 4, the actuator of the compressed air inlet valve 11 receives an impulse to open the valve 11 from the unit 12 of the central c 107725 5. Blasting through the manifold 7 and the holes may start with the roll 2a in the position of Fig. 1. The central unit 12 obtains information on the rotation speed of the roll 2a by any known method and information on the position of the holes from the motion monitoring sensor 13 of the roll 2a which informs the central unit when the blowing holes 9 After N. The operation of the cutting device 4 is synchronized by means of the position information of the holes so that, when cutting occurs, the holes are in the aforementioned right position before the cutting-10 position of the cutting device 4 and for this purpose the cutting device 4 is controlled by the central unit 12. Fig. 2 illustrates a situation when the web W is broken, whereby the new end of the web starts to follow the rotating spool roll 2a from the holes 9 below to the truncated end of the web W by the stabilizing air jets extending the web W 15 to the outer surface of the diaper . Even at or shortly after the cut-off, the valve 11 may close, causing the pressure in the manifold 7 to drop rapidly. For example, when the overpressure in the manifold is about 2 bar and the volume in the manifold 7 is about 0.0051 m3, the pressure drops to 0.02 bar within 55 ms after the valve is closed. When the new end of the new end of web 20 comes to nip N after about 3/4 of rotation, i.e. after about 80 ms for a 900 mm diameter spool reel and about 25 m / s web speed, the pressure in the distribution channel has already dropped to near normal, that there is no harm in air blowing: anymore when the web W begins to rotate a second turn around the spool roll 2a. If this did not happen, compressed air would no longer flow out of the grooves into the free ·: ·· air and pressure under the paper web could release the web ♦: ··: from the surface of the roll. Therefore, it is preferred that the volume of the air channel 7 and the associated piping is as small as possible. It is likewise advantageous to use a fast acting solenoid valve as a valve 11. If necessary, the blowing system 30 is underpressure controlled by the central unit 12 at a suitable stage, e.g.

• · · · · ·: · *: It is clear to the skilled artisan that the speed of the paper machine and the diameter of the reel:: ··: 35 determine the time of operation. Web Cut Off. and the time at which the blow is stopped is determined by the control unit 12, and the parameters given to the central unit may be precisely the running speed · ··· * and the diameter of the reel roll. The running speed can also be obtained from the rotational speed sensor in connection with the reel roll 2a, which continuously measures it and informs the control unit to perform the functions (cut-off, ie shut-off device 4 and blow-off, ie closing valve 11 and opening any vacuum valve 11 ').

However, stopping the blow at the right time is not critical for operation because the small overpressure that remains under the full web cycle is no longer able to lift the web off the roll surface.

10

A great advantage of the process according to the invention is that when the web is cut off and the end of the web is immediately "captured" on the surface of roll 2a, no crumpled paper is produced at the bottom of the empty reel roll 2a, which results in maximum postprocessing yield. Also, there is no waste paper on the surface of the 15 filled reels.

A preferred embodiment of the invention has been described above. It will be apparent to one skilled in the art that many different sensors or devices can be used to control the air jet, and the kek-20 invention is not tied to their quality or mode of operation. The preferred method is to use electronic devices, but other types are also possible. To determine the position of the hole row, position detecting sensors can be used which detect a particular position of the rotating member according to roll 2a or its rotational movement '··' · ·, whereby this identification information corresponds to the position of the hole row or region at a particular position. An- ·: ··: The handle may be optical to detect a particular character, or inductive, *: ··: whereby it will recognize a piece of material moving past it. For the artisan: Y: It is also clear that all types of reel rolls used in a paper machine can be provided with means for blowing air jets. The rows or regions of the holes 9 30 may also be more than one on the periphery of the roll, especially if the diameter of the reel roll is large. Fig. 1 shows two splitting • · HI channels 7 and a row of holes at 180 ° intervals, respectively. In this case, the distribution channels 7 *: ** are optionally coupled to the compressed air source such that only one: · '*: the distribution channel and the corresponding hole row or area participate in the control of the web W: when it comes to a suitable position. The distribution channels 7 may initially only be one because it is sufficient for the effect according to the invention.

• · · • · · «* • · • • 107725

The invention is also not limited to the method of cutting paper web W, but can be used to guide the web W around a new reel reel 2a, for example, when breaking occurs by partially forming a pouch against the reel reel or by guiding the expanding strip off the reel.

In the figures which illustrate cutting by means of a full-width cut stroke, the auxiliary blower with nozzles external to the reel roll 2a is not shown, since the air jets coming from the roll are as such sufficient to lift the web around the reel roll. However, such external auxiliary blows can also be used in this context.

Em. the air channel duct stays inside the reel roll 2a after the machine roll is ready and offers the possibility of using either air blowing or even suction for further processing of the roll R, since the end of the roll can always be connected to compressed air or vacuum.

In this context, the terms air and compressed air refer to all caustic substances and mixtures thereof by which the effect of the invention can be achieved.

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• As a 1 ··· ♦ * · ♦ • • • ♦ «• · 1 • · • · · ♦ · •« · »·

Claims (13)

A method for replacing a reel in a reel having a reel cylinder (1), an inflatable reel (R) formed from a web emerging from the reel roll (2) through the reel roller (2) and an empty reel reel (2a) introduced for replacement, W) runs some distance on the surface of the blank of the reel roll (2a) to ensure replacement of the roll, characterized in that in the method the end of the cut web (W) is guided around the surface of the replaceable blank roll (2a) by air jets. Method according to Claim 1, characterized in that the air jets are blown in the direction of rotation of the roll (2a). Method according to claim 1 or 2, characterized in that the air jets create a vacuum between the sheath (5) of the roll (2a) and the web (W). Method according to one of the preceding claims, characterized in that the air jets are blown along the circumferential grooves (6) on the surface of the jacket (5). Method according to one of the preceding claims, characterized in that the air jets are timed by means of a control unit (12), a shut-off valve (11) and a sensor (13) for monitoring the rotation of the reel roll (2a). • · A method according to claim 5, characterized in that the air jet is discharged from the shell (5) of the roll (2a) in the sector of the roll circumference, where the web (W) passes around the roll before the point (14) where the web .. (W) separates from the roll and is followed by the point at which the web (W) is cut. 4 4 * 4 4 4 «4 7. The method according to any one of the preceding claims, known as # 4 «4. ·· *. 35 means that the shut-off valve (11) controlling the air jets is closed automatically. at least before the air jet discharge point follows the surface (W) of the web (W) surrounding the reel roll (2a) and: *** i of the surface of the shell (5) of the roll (2a). 9 107725 A method according to any one of the preceding claims, characterized in that the web (W) is cut with a cutting device performing a full-width web cutting stroke. 5 8 107725 Apparatus in the reel for changing the roll to secure the end of the truncated web (W) to the surface of the empty reel (2a) after cutting the web, the device comprising a reeling cylinder (1), a filling roll (R) formed of web (W) an empty reel reel (2a), characterized in that the reel reel (2a) has a built-in air channel which can be connected to a source of compressed air, opening openings or gaps in the casing (5) of the roller (2a) so that air jets oriented in the direction of rotation of the roll (2a) along the surface of the shell (5). 15 Device according to Claim 9, characterized in that the openings or slots are formed by holes (9) at a certain slope (a) against the tangent of the jacket (5) in the direction of rotation of the roll. Device according to Claim 9 or 10, characterized in that the openings or slots open in the grooves (6) formed on the surface of the jacket (5). Device according to one of the preceding claims 9 to 11, characterized in that the openings or slots are connected to a distribution channel (7) transverse to the circumferential direction of the diaper (2a) fixed to the inner side of the diaper (5) of the roll (2a). . • M A device according to any one of claims 9 to 12, characterized in that it comprises a control unit 30 (12) for controlling air jets, which is connected to a rotation monitor for the roll (1a). the sensor (13) and • ·. : ·; a shut-off valve (11) arranged to close the compressed air connection to the openings or gaps. 2 · * · · • · · 4 · · 4 4 • 4 * 4 4 4 · • 44 4 4 4 4 4 4 · 4 4 4 4 · • 4 4 4 4 4 4 4 4 · 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 10 107725