FI91547B - Arrangement in a paper machine to produce oscillating motion in the doctor blade - Google Patents

Description

91547

Device for implementing a scraper blade oscillating motion in a paper machine Anordning i pappersmaskin vid förverkligande av oscilleringsrörelse hos schaberblad 5

The invention relates to a device for implementing the oscillating movement of a scraper blade in a paper machine.

10 It is known from the prior art to bear the oscillating movement of a scraper with ball bearings. The purpose of the scraper blade oscillation movement is to introduce a lateral movement of the scraper blade, which effectively removes contaminants adhering to the roll surface. The function of the scraper blade is thus not only to remove the paper web into the pulper at certain positions, but also to keep the roll surface clean. In order to be able to keep the roller surface clean, a lateral movement of the blade 15 is necessary. The required lateral movement is small only about 8 mm in both directions from the center position of the blade. Prior art solutions have used ball bearings for lateral movement bearings. As the scraper body weighs up to 2000 kg, high forces are applied to the bearing. In addition, since the oscillating movement is very small and since in bearing often only a few bearing rollers are carried, large wear forces are caused on the bearing 20 for a small area. Therefore, the bearing does not last long and must be renewed relatively quickly.

This application seeks to find a new type of oscillating motion bearing method and bearing solution.

25

In the invention, it is realized to use in the implementation of the oscillation motion the so-called rocker bolts, thus avoiding the use of prior art bearing rollers. According to the invention, the shaft end of the scraper blade body is connected to a rocker arm which is moved by an oscillating device. Thus, the implementation of the oscillating movement according to the invention does not require bearing rollers, but many plain bearings can be used in the solution. Thus, the solution according to the invention avoids all the problems of the prior art.

2,91547

The device solution according to the invention is mainly characterized in that the scraper blade of the scraper blade is mounted on its shafts by bearing means comprising a pivot body articulated for pivoting with respect to an axis relative to the bearing housing and with shafts to an axis associated with the scraper body.

5

The invention will now be described with reference to some preferred embodiments of the invention shown in the figures of the accompanying drawings, to which, however, the invention is not intended to be exclusively limited.

Figure 1A shows a prior art implementation of the scraper oscillation movement in a cross-sectional view.

Figure 1B shows the components used in the solution of Figure 1A.

Figure 2 shows a basic axonometric view of the position of the scraper in connection with the roll of the paper machine.

Figure 3 shows an implementation solution of the oscillating movement according to the invention from the machine direction of a paper machine.

20

Figure 4 shows the articulation of the other end of the scraper body in a cross-sectional view.

Fig. 5 shows a view from the direction kj in Fig. 4.

Figure 6A shows a piston / cylinder mechanism providing an oscillating motion.

Figure 6B shows another embodiment of a piston cylinder mechanism providing an oscillating motion.

Fig. 1A shows a solution used in the prior art for bearing the scraper blade oscillation movement. The bearing housing P is fitted with ball bearings E1, E2, E3 ...,

II

«3 91547 where the oscillating movement device M moves the axis A connected to the scraper body R in the direction A The required movement of the scraper blade T is only of the order of 8 mm in both directions. Since the bearing receives the weight of the scraper blade and in particular of its body, a large load is generated on the bearing ball bearings E ^ E ^ Ej .... 5 The scraper blade T is detached from the roll surface by means of a cylinder device S with the cylinder device S connected between the lugs Kt and K2. Contamination of the shaft A is prevented by the cover D between the lugs K1 and K2.

Figure 1B is an exploded view of the structure of Figure 1A. The ball bearings E ^ E ^ ... 10 are located in the retaining ring C between the inner ring Fj of the bearing and the outer ring F2. The frame beam R of the blade T of the scraper K comprises an end shaft A, to which is connected the device for generating the oscillation movement shown in the figure by the fastener M.

Figure 2 shows the position of the scraper blade in connection with the roll of the paper machine.

15

Figure 3 shows an improved bearing solution according to the invention for implementing an oscillating movement. The scraper 10 comprises a scraper body 11 to which a scraper blade 12 is connected. The scraper body 11 is fixedly connected to shafts 13a and 13b. The scraper blade 12 is rotatable about the geometric central axis Xj of the shafts 13a, 13b. The pivoting movement of the scraper blade 12 about the axis Xj and the oscillating movement of the scraper blade 12 in the directions L1, X1 in the direction of the axis Xj are enabled by bearing solutions 14a, 14b which are similar. The bearing means are located inside the bearing housing 15a, 15b.

Figure 4 shows the bearing means 14a seen from the machine direction. A shaft 13a associated with the body of the scraper blade 25, its body beam 11, is connected to the body 18. The body 18 is articulated to pivot on shafts 19a, 19b relative to a pivot body 16, which pivot body 16 is further mounted to pivot on a shaft 17 connected to a bearing housing 15a.

30 In Figure 4, the apparatus is located in the center of the oscillation. The arrows in the figure illustrate an 8 mmm oscillation movement in each direction. Since the movement is «4 91547 small, only a small rise of the scraper blade occurs in the movement. The bearing means 14a, 14b are similar for both shafts 13a, 13b of the scraper body 11. Since the shaft 13a rises somewhat in the oscillating movement, the passage G of the shaft 13a through the body 13a must allow the above-mentioned movement, i.e. the opening G must be somewhat larger than the diameter of the shaft 13a.

Fig. 5 shows the bearing means 14a seen from the direction kj of Fig. 4. The shaft 13a associated with the frame beam 11 of the scraper blade is connected to a body 18 which is articulated to pivot about a geometric axis X2 and is connected by 10 shafts 19a, 19b to a pivot 16. The pivoting movement 21 between the pivot 16 and the body 18 Correspondingly, the pivot body 16 is mounted by bearing means 22 so that the body 16 pivots about the geometric central axis X3 of the shaft 17. Thus, if the weight of the scraper blade and the scraper body 11 is e.g. Said weight is further distributed through the bearing means 20a, 20b to the bearing means 22a, 22b, 23a, 23b. Thus, the bearing means 22a, 22b, 23a, 23b each receive only 500 kg. The bearings 23a, 23b are plain bearings. Their bearing surface can be easily increased by extending the plain bearings 23a, 23b, thereby reducing the surface pressures of the bearings and increasing the bearing life.

20

Figure 6A shows the cylinder / piston solution used in the implementation of the oscillation movement. The end 13 'of the shaft 13a is formed as a cylinder body comprising a piston 24, which in the embodiment of the figure is in two parts and comprises portions 24a, 24b and a smaller diameter intermediate portion 24c connecting them. The piston rod 25 is articulated by a joint 26 to the end plate 15a '. The joint 26 allows a small rise due to the oscillating movement of the shaft 13a. A pressure medium, preferably oil, is passed through the channels 27a, 27b at the end 13 'of the shaft 13a to each side Pj.Pj of the piston 24, optionally depending on which direction the shaft 13a is moved. The pressure medium is controlled by means of a hydraulic or pneumatic valve 30, not shown.

Il 5 91547

Fig. 6B shows another embodiment of a moving device providing an oscillating movement with a one-piece piston 24. Piston rods 25a, 25b connected to the piston 24 on each side of the piston. The arm 25b is adapted to move in the guide hole 28 at the end of the shaft 13a. Through the pressure medium channels 27a, 27b made at the end of the shaft 5a, the pressure medium is alternately conveyed from one side of the piston 24 to the other depending on the oscillation direction. The piston rod 25b is connected by a joint 26 to the end plate 15a ', thus allowing a small tilting margin for the piston rod 25b.

Claims (6)

6,91547 An apparatus for implementing the oscillating movement (L 1 L 2) of a scraper blade (12) associated with a scraper body (11) of a paper machine scraper (10), the scraper blade (12) being adapted to be in S contact with the roll surface and the body (11) associated with the scraper blade (12) being adapted to be movable in an oscillating movement on the shafts (13a, 13b) connected to the body (11) in a lateral direction with respect to the roll (T) to be cleaned, giving the scraper blade (12) a lateral movement, effectively removing contaminants adhering to it from the paper machine roll (T); the scraper body 10 (11) of the scraper blade (12) is mounted on its shafts (13a, 13b) by bearing means (14a, 14b) comprising a pivot body (16) articulated to pivot with a shaft (17) relative to the bearing housing (IS) and shafts (19a, 19b) ) with respect to the shaft (13) associated with the scraper body (11). Apparatus according to claim 1, characterized in that the shaft (13) 15 comprises a body body (18) connected thereto, to which the shafts (19a, 19b) are connected, the pivoting movement about the geometric central axis (X2) of the shafts (19a, 19b) being mounted by bearing means (20a, 20b; 21a, 21b). Device according to Claim 1 or 2, characterized in that the pivoting movement about the geometric central axis (X3) of the shaft (17) 20 is supported by bearing means (22a, 22b; 23a) between the bearing housing (15) and the shaft (17). 23b). Device according to one of the preceding claims, characterized in that the end (13 ') of the shaft (13a) is formed as a cylindrical body comprising a piston (24), the piston rod (25) being articulated by a joint (26) to the end plate of the housing (15a) (15a '). • Device according to the preceding claim, characterized in that the end (13 ') of the shaft (13a) comprises channels (27a, 27b) through which a pressure medium is passed to each side (P1, P2) of the piston (24), optionally depending on which in the direction of the shaft (13a) and the associated scraper body (11) and the associated scraper. it is desired to move the raa (12). Il 7 91547 Device according to one of the preceding claims, characterized in that the piston (24) comprises piston rods (25a, 25b) on each side of the piston, the arm (25b) being adapted to move in the guide hole (28) of the end (13 ') of the shaft (13a) and that the device comprises pressure medium channels (27a, 27b) in the shaft (13) and that the piston rod (25a) 5 is connected by a joint (26) to the end plate (15a *), thus allowing a small tilting margin for the piston rod (25b) in oscillating movement. 91547 8