US1978982A

US1978982A - Suction apparatus

Info

Publication number: US1978982A
Application number: US656239A
Authority: US
Inventors: Francis L Barstow
Original assignee: New York Belting & Packing Com
Current assignee: New York Belting & Packing Co; New York Belting & Packing Com
Priority date: 1933-02-11
Filing date: 1933-02-11
Publication date: 1934-10-30
Anticipated expiration: 1951-10-30

Description

Oct. 30, 1934. F. L., BARsTow SUCTION APPARATUS Filed Feb. l1, 1955 INVENTo @l ATTORN Patented Oct. 30, 1934 SUCTION APPARATUS Francis L. Barstow, Springfield, Mass., assgnor to New York Belting & Packing Company, Passaic, N. J., a corporation of New York Application February 11, 1933, Serial No. 656,239

12 Claims.

My invention relates to suction apparatus, and more particularly to suction rolls for use in paper making machinery for extracting moisture from pulp on a porous conveyor, such as a felt belt.

5 In the manufacture'of paper it is customary practice to convey the pulp from the Fourdrinier wire or other sheet forming devices through pressure rolls, commonly called presses, to drying drums for the extraction of liquids. Such press l rolls are arranged in pairs, the upper roll usually having a polished continuous surface. Various metals, rubber, wood, stone and composite material may be used for such rolls. The lower roll f is frequently provided with means for removing l moisture from the pulp by the application of a vacuum.

One form of lower pressure roll which is frequently used is a metal shell supported at its ends by heads resting in bearings. The shell is provided with perforations which rotate past a stationary suction box. The suction box is disposed adjacent the area of engagement between the upper and lowerKrolls sov that'the suction is applied to the area of the lower roll in cooperative engagement with the yupper roll at any time.

'I'he outer cylindrical surface of the shell is preferably provided with a layer of relatively soft material 'such as rubber. The thickness of this coating may be of the order of one inch. 'I'his 'outer surface is also perforated so that the pulp carrying conveyor disposed between the two rolls is subject to a vacuum for withdrawing liquids from the pulp on the conveyor. The porous conveyor belt is frequently driven by the bite of the rolls. 'This also provi`des pressure for forcing the liquids from the pulp and for compacting the pulp.

Heretofore considerable diiculty has been encountered in the manufacture of perforated coated press rolls. The shell proper has usually been made of metal which is perforated with a. great many smaller holes of the order of of an inch in diameter on circumferential and Widthwise centers of the order of it; to 1% of an inch. The

drilling of such holes offers no particular diiiiculty. However, when the covering is applied, particularly in the case of a rubber covering, it isfin the f rm of a continuous sheet which extends over/and closes the openings in the underlying metal. Thereafter it is necessary to sepa- 'rately drill the openings in the covering. The problem of securing registry between the openings in the covering and those in the underlying metal of the shell is extremely diicult, even in the manufacture of new rolls. Where it is desired to recover a used roll, the problem of securing registry is much more difficult. In many instances it is desired to recover the roll at a factory or plant other than vthat of the original manufacturer of the roll. In such a case it is rst necessary to secure from the original manufacturer of the roll an index of the drilling of the openings in the metal roll or to laboriously plot them. Because of these conditions the paper manufacturer usually takes the roll out of service and ships it to the manufacturer.

I provide suction apparatus in which the coating is separable from the metal shell so that the replacement /of the coating does not take the metal shell out of service for a great length cf time, nor does it require that the shell be sent to a specially equipped factory. By providing the coating in the form of a belt having a length considerably in excess of the circumference of the roll and by providing perforations in the belt and then running the belt between the pulp conveying belt and the metal shell as the latter rotates, suction is eifectively applied to the pulp. Preferably the openings in the belt at the shell engaging surface are of greater diameter than are the openings in the shell. If desired the outer ends of the shell openings and the inner ends of the conveyor openings may be flared. Also the number of openings in the belt may be in excess of the number of openings inthe shell. In either or both cases a sucient number of the belt openings will be in registry with the shell openings to insure the application of a vacuum to the porous pulp conveyor which is momentarily supported by the lower press roll;

Provision is made for Atensioning and guiding the perforated belt. Provision is also made for cleaning the porous belt of particles of pulp or other material which may be carried by it.

The accompanying drawing illustrates a present preferred embodiment of my invention, in which Figure 1 is a diagrammatic view, partially in elevation and partially in section, of the suction apparatus embodying my invention;

Fig. 2 is a cross sectional view of a portion of 100 the shell and perforated belt;

Fig. 3 is a broken plan view of a portion of the shell and perforated belt; and

Fig. 4 is an elevational view of adjusting and guiding apparatus for the perforated belt.

Referring to the drawing, a porous conveyor belt 1, generally of felt, is advanced by driving rolls 2 for engaging a partially dried sheet of pulp 4. The porous conveyor belt 1 and the sheet 4 are fed between an upper or top press roll 5 and 110 order of 4/l0 to 5/10 of an inch. It is to be understood that these values are exemplary and are not to be considered limitations of the invention ing the rubber to the as different manufacturers use different sizes and spacings of openings. The shell 7 is mounted in brackets 9 by stub shafts l0 extending from heads 11. One of the heads may be provided with a gear 12 for rotating it. The conveyor belt l is advanced by the bite of the rolls 5 and 6.

A stationary suction box 14 is mounted within the shell 7 by supporting arms 15 which may extend outwardly from one or both of the stub shafts 10. A flexible pipe line (not shown) may be attached to one of the stub shafts for applying vacuum to the interior of the suction box 14 through a channel or channels in the arm or arms v15. 'Ihe details of these connections are 'well known in the art, for which reason a full description is omitted from the present specification.

For providing a cushioning surface between the conveyor belt 1 and the metallic surface of the shell 7, which is oftenof bronze, I provide a perforated belt 16 of flexible material such as rubber. Where rubber'is used as the material for the belt 16 it should be cured and may be of the same general characteristics as rubber covers now used on such rolls. However, due to the elimination for the need of permanently attachmetal of the shell 7 the thickness is materially reduced. This also eliminates the need for specially bonding the coating surface to the shell 7 which has heretofore been a very difcult and costly operation. The rubber coatings permanently attached now normally used are of the order of 111g inches in thickness including the bonding layers and the outer cushioning layers. The belt 16 may be of the order of H of an inch in thickness which is a common thickness for a cushioning rubber. Openingsl' are provided in the belt 16 for cooperation with the openings 8 in the shell 7. To this end the outer ends 18 of the openings 8 may be ared to cooperate with flares 19 at the inner ends of the openings 17. The sizes and spacings of the openings 17 may be the same or vary slightly from the sizes and spaces of the openings 8 as the provisions of the flaring ends of these sets of openings insures that, regardless of the relative positions of the shell 7 and the belt 16, there will be a sufcient'number in contact to insure the application of a vacuum in that portion of the belt 16 outside of the suction box 14.

Because of the tendencyvfor slippage between the shell 7 and the belt 16 owing to the driving force transmitted to the porous conveyor belt l, it is desirable to tension the belt 16 and insure that it lhas a suiiicient frictional engagement with the shell 'l to prevent slippage. 'Ihis may be accomplished by causing the belt 16 to engage the surface of the shell 7 throughout a large angle, an engagement of substantially 240 being shown in Fig. 1. Also a tensioning roll 20 may be mounted in brackets 21 having adjustment screws 22 'and 24 for tensioning the belt 16. Flanges 25 are provided at`the ends of the roll 20uto prevent the belt 16 from running oi the ro In order `to remove particles of pulp, lint, and the like, from the belt 16, a spray line 26 may be provided for washing the belt. An air blast may be used in lieu of the spray 26. The spray 26 is preferably placed internally of the beltl6 so as to wash the refuse outwardly through the openings 17 and thus rid the belt of it. A catch basin 27 may be provided for removing the wash Water and the refuse.

Referring to Fig. 4 for positioning jthe 'belt 16 with respect to the shell 7, I may prov1de positive guiding means in lieu of the tension roll 20 shown in Fig. l. To this end I provide a guide flnger 28 which is stationarily mounted on a bed 29. An adjustable finger 30 on the bed 29 is controlled by a screw 31 extending through a boss 32. By adjusting the relative positions of the fingers 28 and 30 various widths of belt may be guided. For positioning the bed 29 relative to the shell 7, I provide a base 34 having a way 35 for the bed 29. A screw 36 operated by handwheel 37 enters a threaded bore 38 in the bed 29 for adjusting it laterally with respect to a boss 39 on the base 34.

If desired, the guiding apparatus shown in Fig. 4 may be used in conjunction with the tensioning roll 20, or the tensioning roll 20 may be given lateral adjustment.

With the apparatus of the present invention 'the need for accurate drilling of openings in a rubber or other soft covering for a suction roll is eliminated, since the covering of the present invention is in the form of a from a permanent covering vulcanized or otherwise fastened to the shell 7. 'llihe dispositioning of the perforations 17 in the belt 16 is such that a sumcient number of them will be in a co-operative contact with perforations 8 at the suction box 14 to effectively withdraw the moisture from the belt 1. This construction also eliminates the need for removing the shell 7 from a paper mill and transporting it a considerable distance to have it recovered.

While I have shown and described the present preferred embodiment of the invention in connection with paper machinery, it is to be understood that the invention may be otherwise utilized and embodied within the spirit of the invention and the scope of the appended claims.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. In suction apparatus, the combination with a movable surface having ings therein, andy means for applying a condition of vacuum to the inner ends of said openings, of a separable cushioning layer having perforations flaring outwardly toward the flared perforations in said surface whereby a condition of vacuum is transmitted through said surface and cushioning body without requiring perfect registry of the openings therein.

2. In suction apparatus, a support having a plurality of openings extending therethrough, means for applying a condition of vacuum to certain of said openings, and a separable cushioning body engaging a portion of the surface of said support, said cushioning body having openings extending therethrough of suicient number and shape to transmit the condition of vacuum from thelsupport to the outer surface thereof without requiring precise registry of the openings in said support land cushioning body.

3. In suction apparatus, a support having a belt as distinguished outwardly flared opensu-flicient number and shape to transmit the condition of vacuum to the outer surface thereof Without requiring precise registry of the openings in said support and cushioning body.

- v 4. The combination with a yperforated metallic press roll, of a perforated rubber cushioning belt the cushioning belt.

fortransmitting a condition of vacuum from the interior of the roll .to the exterior surface of 5. 'I'he combination with a perforated bottom press roll, and means for applying a condition of vacuum to at least Va portion of the interior of said roll, of a separable, perforated rubber cushioning belt directly engageable with a portion of the outer surface of said roll for carrying material traversing a pair of press rolls and applying 'a condition of vacuum thereto.

6. The combination with a perforated press roll for a paper machine, and means for applying a condition of vacuum to at least a portion of the interior of said roll, of a separable, perforated rubber cushioning belt directly engageable with a portion of the outer surface of said roll for carrying material traversing a pair of press rolls and applying a condition of vacuum thereto.

7. A belt for a suction device having a plurality of openings therein, the .openings at one face of the belt occupying a larger area of the belt than at the opposite face.

8. Thev combination with a perforated press roll, and means for applying a condition of vacuum thereto, of a perforated rubber cushioning belt having openings for cooperation withthe perforations in said roll for transmitting the conL dition of vacuum, and means for tensioning and guiding the belt.

9. The combination with a roll having perforations for the transmission of a condition of vacuum, and a separable conveyor having vacuum transmitting perforations for cooperation with those of the roll, of means cooperating with a portion of said conveyor separated from said roll for removing foreign matter.

10. 'I'he combination with a roll having perforations for the transmission of a condition of vacuum, and a separable conveyor having vacuum transmitting perforations for cooperation with those of the roll, of a spray for cooperating with a portion of said conveyor separated from said roll for removing foreign matter.

11. 'Ihe combination with a roll having perforations vfor the transmission of a condition of vacuum and a separable conveyor having vacuum transmitting perforations for cooperation with those of the roll, of a spray disposed internally of a position of the conveyor separated from said roll for removing foreign matter.

12. The combination with a roll having perforations for the transmission of a condition of vacuum and a separable conveyor having vacuum transmitting perforations for cooperation with those of the roll, of a spray disposed internally of a portion of the conveyor separated from said roll for removing foreign matter, and a catch basin for conveying the washings away from the