US3483079A

US3483079A - Paper machine press with reverse rotation lump clearing roll

Info

Publication number: US3483079A
Application number: US563264A
Authority: US
Inventors: Edward D Beachler
Original assignee: Beloit Corp
Current assignee: Beloit Corp
Priority date: 1966-07-06
Filing date: 1966-07-06
Publication date: 1969-12-09
Anticipated expiration: 1986-12-09
Also published as: GB1173357A

Description

Dec. 9, 1969 E. D. BEACHL ER 3,483,079

PAPER MACHINE PRESS WITH REVERSE ROTATION LUMP CLEARING ROLL 3 Sheets-Sheet 1 Filed July 6, 1966 INVENTOR. E aWwafiBeac/ger BY e/M/ wwwrwwmws Dec. 9, 1969 E. D. BEACHLER 3,483,079

PAPER MACHINE PRESS WITH REVERSE ROTATION LUMP CLEARING ROLL Filed July 6, 1966 3 Sheets-Sheet 2 g la-@- INVENTOR. 2d zyWdfiBeJc'k Zefi BY W WWW/ NW5 Dec. 9, 1969 E, D. BEACHLER 3,483,079

PAPER MACHINE PRESS WITH REVERSE ROTATION LUMP CLEARING ROLL Filed July 6, 1966 3 Sheets-Sheet 3 I N VEN TOR.

BY QQQ United States Patent 3,483,079 PAPER MACHINE PRESS WITH REVERSE ROTATION LUMP CLEARING ROLL Edward D. Beachler, Beloit, Wi., assignor to Beloit Corporation, Beloit, Wis., a corporation of Wisconsin Filed July 6, 1966, Ser. No. 563,264 Int. Cl. D21f 3/08 US. Cl. 162-272 Claims ABSTRACT OF THE DISCLOSURE A pair of press rollers in a paper machine forming a press nip therebetween with a backing roll immediately in advance of the nip for supporting a paper web carried by a felt prior to its entering the press nip; and a lump clearing roll opposite the backing roll spaced a small distance from the paper web and driven in rotation in a direction opposite the direction of movement of the paper web.

The present invention relates to improvements in papermaking machines and more particularly to improvements in the press section wherein lumps are prevented from being carried along on the web surface and entering the press nips.

In a papermaking machine after the web is formed and dewatered on a porous surface such as a Fourdrinier wire it passes through a press section of the machine. In high speed high pressure press nips it is particularly undesirable to have small lumps on the paper surface or on the felt carry along and enter into the nip of the machine since they can damage the felt and press and can create defects in the web.

A feature of the present invention is the provision of a lump clearing mechanism which removes lumps from the surface of the web prior to its entering the press nip and which in one form embodies between first and second press nips a backing roll for supporting and establishing a stable position for the web, and a lump clearing roll positioned in close running out of contact relation with the surface of the web opposite the backing roll and rotated in a direction opposite to the direction of the web travel so that lumps are picked off of the web and thrown in a direction away from the nip Which the web is entering.

It is accordingly an object of the present invention to provide an improved mechanism for preventing damage to the felt and nip and to the web by removing lumps from the surface of the web or felt before it enters the nip and which is simple and reliable in construction and capable of operating satisfactorily on a high speed paper machine.

A further object of the invention is to provide an improved lump clearing device for a papermaking machine which does not interfere with the normal operation of the machine, and will not cause difficulty in startups and during operation, and which is capable of operating over a long life without adjustment or attention.

Other objects, advantages and features will become more apparent with the teaching of the principles of the present invention in connection with the disclosure of the preferred embodiments thereof, in the specification, claims and drawings, in which:

FIGURE 1 is a schematic side elevational view of a portion of a press section of a paper machine showing lump removing mechanism embodying the principles of the present invention;

FIGURE 2 is a side elevational view showing a continuance of the machine of FIGURE 1; and

FIGURE 3 is a schematic somewhat enlarged side ICC elevational view of a portion of the machine embodying the lump removing mechanism and showing details.

As shown on the drawings:

As illustrated in FIGURE 1, the travelling paper web W is received by first press nip N-l formed between a pair of rotating press rolls 10 and 11. While the press rolls may take various forms known to the papermaking art, the lower roll 11 may be a grooved roll adapted to receive water pressed from the web into a felt F-1 carrying the web. Several means are provided for removing water from the grooves of the roll 11. Such a construction is shown and described in US. Patents Nos. 3,198,693; 3,198,694; 3,198,695; 3,198,696; and 3,198,697

The web is carried over a backing roll means 14, FIGURES 1, 2 and 3, with the felt F-1 turning down over the backing roll 14 and the web passing through an open drawer and received by a second felt F-2. The backing roll rotates with the felt and provides a stable support for the web and felt so that the location of the web will be positive for operation of a lump clearing roll 15.

The lump clearing roll 15 is positioned opposite the backing roll, and above the web, and is driven in a rotational direction so that its surface rotates opposite the direction of surface movement of the web W. The lump clearing roll 15 is driven by a suitable driving means D which may be in the form of a variable speed motor. The roll is preferably driven at a speed in the range of from equal to or higher than felt or web speed to make an out going nip. An out going nip refers to the fact that the lump clearing roll rotates against the direction of the close running lump carrying web.

Following the lump clearing roll, the web passes on to be carried by the second felt F-Z into the second nip N-2 formed between

opposed press rolls

12 and 13, FIGURE 2. These press rolls may be of conventional construction with the upper roll being a solid roll and the lower roll may take various forms such as a grooved roll or rubber covered section roll.

The lump clearing roll 15 has a smooth outer surface and while various constructions are acceptable a preferred form is to have the roll formed of fiberglass. It has been found that the coaction between the fiberglass and the.

lumps of the type which form at the top of the web is such that they are positively and effectively removed and are kicked backward in a direction away from the nip N-2. Where the machine is being started and only a narrow tail of paper is passing through the machine, the felt is exposed to the roll 15 and it clears lumps off the felt.

The roll is supported on bearings 19 at its ends, FIG- URE 3, carried in bellcranks at the ends of the roll 15. The bellcranks are pivotally supported on a pivot 17 and the upper arm of the crank is pivotally connected at 20 to a piston rod 21 of a fluid operator such as a cylinder or bellows which is pivotally supported at 23. Suitable fluid pressure lines, not shown, are connected to the cylinder for operating the piston rod to move the lump clearing roll to a non-operating cleaning and threading dotted line position or to an operating solid line position. In the operating solid line position the surface of the lump clearing roll 15 is in close running relation to the surface of the web with a very small space S preferably in the range of A to 2 inches.

The space S is regulated by a stop bolt 24 which is engaged by the upper arm of the bellcrank 16 to limit its travel. The stop bolt is threaded into a bracket 25 on the frame 18 which carries the lump clearing roll 15 by supporting the pivot 17.

In order to prevent the web from following up around with the lump clearing roll, such as at times of startup when the web tends to flutter, or at times when the web would break, a shield 26 is positioned following the clearing roll 15. The shield is movable in positions between a location close to the clearing roll (shown by the dotted line position in FIGURE 2). In this position it will be prevented from following up round the lump clearing roll 15, although in normal operation the shield 26 can be moved down to the solid line position.

The shield is pivotally supported on a pivot 27 and moved to its positions by an operating arm 28 pivotally connected to a piston rod 29 of a piston slidable in a cylinder 30.

In summary of operation, the paper web W carried on a felt F-1 passes from the first nip N-1 of a press toward a second press nip N-2. It is supported by a backup roll 14 and lumps on the surface are cleared by counter-rotating roll 15 which kicks the lumps off of the roll in a direction away from the nip N-2.

Thus it will be seen that I have provided an improved novel structure which meets the objectives and advantages above set forth. The structure is effective in operation and capable of very reliable efiicient operation removing lumps from the surface of a travelling paper web at high speeds without damaging the web and providing positive protection for the nip, felt and web.

The drawings and specification present a detailed disclosure of the preferred embodiments of the invention, and it is to be understood that the invention is not limited to the specific forms disclosed, but covers all modifications, changes and alternative constructions and methods falling within the scope of the principles taught by the invention.

I claim as my invention:

1. In a press section of a papermaking machine, the combination comprising,

opposed press rolls forming a press nip receiving and dewatering a traveling paper web carried by a felt,

a backing means in advance of said nip in supporting relationship with the web and felt to establish a position therefor, a lump clearing roll opposite said backing means, a means positioning said lump clearing roll in a lump clearing relationship with the surface of said web,

said lump clearing roll removing lumps from the web without engaging the web and preventing the lumps from entering said nip, and

means for driving said lump clearing roll in a direction of rotation opposite to the direction of web travel.

2. The press section as defined in claim 1, wherein the backing means consists of a backing roll supporting the web, said backing roll rotating at the surface speed of the web.

3. In a press section of a papermaking machine the combination in accordance with claim 1 wherein a shield is positioned following the lump clearing roll and on the same side of the web preventing the web from piling up on the lump clearing roll.

4. In a press section of a papermaking machine, the combination comprising,

opposed press rolls forming a first press nip receiving a traveling paper .web carried by a felt and dewatering the web,

opposed second press rolls forming a second press nip receiving said web carried by a felt and further dewatering said web,

a backing roll between said nips in supporting relationship with said web and felt, a lump clearing roll opposite said backing roll rotating in a direction opposite the direction of web travel,

means for positioning said lump clearing rolls in a close running out of contact relation with the surface of said web, and

means driving the lump clearing roll in a direction of rotation opposite the direction of surface travel of the web so that lumps will be thrown backwards away from the second nip.

5. In a press section of a papermaking machine the combination of claim 4 including a first felt carrying the web through said first press nip and over said backing roll with a second felt receiving and carrying the web through said second nip.

6. In a press section of a papermaking machine as defined in claim 4, wherein the means for positioning the lump clearing roll is movable between said close running relation with the surface of the web and a threading and cleaning position spaced from the web.

7. In a press section of a papermaking machine, the combination in accordance with claim 4 wherein said close running out of contact relation is between A and 2 inches.

8. In a press section of a papermaking machine the combination in accordance with claim 4 wherein the lump clearing roll is driven at a speed in the range of equal to or faster than web speed.

9. In a press section of a papermaking machine the combination in accordance with claim 4 wherein said lump clearing roll is constructed of fiber glass.

10. In a press section of a papermaking machine the combination in accordance with claim 4 wherein the roll of the first press nip which engages the side of the web engaged by the backing roll is grooved to receive water.

References Cited UNlTED STATES PATENTS 2,441,169 5/ 1948 Roman 162-3 14 XR 3,257,226 -6/ 1966 Thwaites l1764 3,216,891 11/1965 Kozich 162--308 XR S. LEON BASHORE, Primary Examiner R. H. TUSHIN, Assistant Examiner US. Cl. X.R. 162-205, 358