US1742991A - Suction cylinder for paper-making machines and the like - Google Patents
Suction cylinder for paper-making machines and the like Download PDFInfo
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- US1742991A US1742991A US339956A US33995629A US1742991A US 1742991 A US1742991 A US 1742991A US 339956 A US339956 A US 339956A US 33995629 A US33995629 A US 33995629A US 1742991 A US1742991 A US 1742991A
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- suction
- cylinder
- channels
- roll
- recesses
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F3/00—Press section of machines for making continuous webs of paper
- D21F3/02—Wet presses
- D21F3/10—Suction rolls, e.g. couch rolls
- D21F3/105—Covers thereof
Definitions
- su'cnou CYLINDER FOR PAPER MAKING mourns m ram mm Filed Feb. 14, 1929 2 Sheets-Sheet 1 INVENTOR ROLAND BLYTH HEYS qy izz's ziiarlzeje M MM R. B. HEYS Jan. 7, 1930.
- This invention relates to suction cylinders, or rolls, of machines for making paper, paperboard, mill-board and the like of the type described and claimed in the specification of my 5 U. S. Patent No. 1,591,921, issued July 6th, 1926, hereinafter referred to as the main patent.
- a suction cylinder or roll which is adapted to abstract moisture from pulp or other material carried by a band passing over part of its periphery, is provided with longitudinal channels, into which the moisture passes and which periodically communicate with a recess or recesses in an end cover or covers connected with a suction device in order to abstract the moisture therethrough, and means are provided for retaining in the longitudinal channels any liquid which may remain there after said channels have passed the recess or recesses in the end cover, or covers, in order to prevent such liquid from wetting the pulp or other material on the next revolution of the cylinder or roll.
- the present invention consists in an improved suction cylinder or roll of the type described and claimed in the specification of my U. S. Patent No. 1,591,921 in which the suction cylinder or roll is rotated at high speed, and the trailing sides of the longitudinal channels, instead of being substantiall radial, are directed inwardly and rearwar ly behind the radius so as to form pockets, which provide the means for retaining any liquid that may remain in the longitudinal channels after they have passed the said recess, or recesses, said li uid being retained in the pockets due to the hlgh speed of rotation.
- the present invention also consists in an improved suction cylinder or roll of the type described and claimed in Patent No. 1,591,921 in which an endless flexible belt (preferably of rubber) running over auxiliary rollers is provided at one or both ends of the suction cylinder or roll, andis adapted to make contact with the suction roll over the arc of its
- the object of the present invention is to periphery subjected to suction in order to confine the width over which the suction is applied to correspond with the width of the pulp or other material carried by the band.
- the present invention also consists in an improved suction cylinder or roll of the type described and claimed in Patent No. 1,591,921 1n which curved or bent strips of metal or other material are inserted into the mouths of the longitudinal channels where the open out on to or towards the periphery of t e suction roll, their curved or bent portions proecting into the channels, and holes beingprovided in the central zones of the curved or bent strips to allow the moisture from the wet pulp to flow therethrough to the inside of the channels, while the curved or bent.
- the present invention also consists in an improved suction cylinder or roll of the type described and claimed in Patent No. 1,591,921 in which a plurality of recesses are provided which successively communicate with the said longitudinal channels to abstract moisture therefrom, the amount of suction applied being different for the different recesses.
- the present invention further consists in an improved suction cylinder or roll of the type described and. claimed in Patent No. 1,591,921 in which the channels are divided by longitudinal partitions, which extend towards the interior of the channels, and are provided with holes or recesses towards the interior of the channels, so that moisture from the wet pulp ma flow through said holes or recesses during the suction period, but the partitions will act as traps to prevent the excess water being returned to the periphery of the suction rollafter the suction period.
- FIG. 7 is a front view of one of the partitions shown in Figure 6.
- Figure 8 is a sectional elevation of the improved suction roll shown in Figures 1 and 5, as fitted in a machine in which the pulp carrying band passes over the rear half of the drum.
- the suction cylinder or roll 1 rotates in a clockwise direction as indicated by the arrow and is formed with a plurality of longitudinal channels 2 having trailing sides 3 directed inwardly and inclined rearwardly behind the radii of the cylinder to form pockets. These channels preferably extend substantially parallel with the Y face and-leaves said roll at a axis of the cylinder, but need not necessarily
- the pulp carrying band 4 enters into contact with the roll at a point 5 on its upper surdownwardly moving point 6 thereof.
- the spaces 7 and 8 (shown dotted) diagrammaticall indicate the positions of end recesses, whic are located in an end plate of the cylinder as in the main patent and which are under suction and with which the longitudinal channels 2 successively communicate.
- the apparatus works in the following manner :As the longitudinal channels 2 pass the suction recesses 7 and 8, they are subjected to the action of suction, which withdraws moisture from the pulp 9 carried by the band 4' through holes 10 in the peri heral cover: 27 of the roll and thence throug the longitudinal channels 2. These holes 10 are staggered and register with the channels 2. After each longitudinal channel 2 has left the last suction recess 8, the excess moisture therein is retained in the pocket formed by the trailing side 3 by reason of the high speed of rotation of the roll and due to inertia. Such excess moisture will thereby be prevented from flowing back through the holes 10 in the peripheral cover 27 so as to moisten the pulp on the next ,or any succeeding revolution of the roll.
- the suction applied by the first recess 7 is greater than that applied in the subsequent recess 8 and in consequence thereof there is less tendency to open up. the pulp as it is being dried. More than two suction recesses may be provided, and then the suction applied in the first recess is preferably greater than that appliedin any subsequent recess.
- endless belts 11 of flexible material are provided at each end of the suction roll 1 in order to confine the width over which the suction is applied to correspond with the width of the pulp or other material carried by the band.
- These endless belts 11 are shown as passing over auxiliary rollers 12 and 13 which are rotatably mounted upon axles represented by 14 and 15 (see Figure 3).
- the endless pulp carrying band 41 is indicated in Figures 1 and 3 and the pulp carrying portion thereof extends across the width 16 indicated in Figure 2.
- the auxiliary rollers 12 and 13 are slid along their axes 14 and 15 in order to vary the width 16 as desired.
- only one endless flexible belt may be provided, arranged at one end only of the suction cylinder.
- a bent or curved strip 18 is inserted into the mouth of each of the longitudinal channels 2 where the said channel opens on or towards the periphery 27 of the suction roll.
- the bent or curved portion of the strip projects into the channel 2, and holes 19 are provided in or near the centre of the strip in order to allow the moisture from the wet pulp to flow therethrough to the inside of the channel, when said channel passes the end recesses and is acted upon by suction. After passing beyond the suction recesses, however, the bent or curved strip acts as a trap to prevent excess water being returned to the periphery of the suction roll. 1
- each partition consists of a plate 21 with strips 22 bolted or otherwise secured thereto in such a way as to provide holes or open spaces 23 towards the interior of the longitudinal channel. These holes or open spaces 23 act to allow water to pass therethrough when the longitudinal channel is under suction.
- the parti tion 20 will act as a t1 ap to prevent the escape of moisture from flowing back on to the periphery of the roll.
- the arc of contact between the pulp carrying band and the suction roll may extend from close to the lowest point of the roll to near the highest point.
- Figure 8 shows for example such an arrangement as applied to the improved suction roll illustrated in Figures 4 and 5.
- said are of contact may extend from close to the highest point of the roll to a downwardly moving point as indicated in Figure 1.
- a high speed suction cylinder having longitudinal channels located adjacent its periphery and subject to suction for a limited period, said channels being inclined inwardly and from the radii of the cylinder, forming pockets to catch and retain, by force of rotatation of said cylinder, surplus liquid remaining in said channels after the suction period.
- a suction device com rising a rotatable suction cylinder having a jacent its periphery a plurality of longitudinal channels, said channels being inclined inwardly and from ROLAND BLYTH HEYS.
- each of said recesses having a different amount of suction a plied thereto.
- a suction device comprising a rotatable suction cylinder having adjacent its periphcry a plurality of longitudinal channels, said channels being inclined inwardly of the cylinder and rearwardly behind the radii of the cylinder to form pockets, a cylinder end formedvwith a plurality of recesses therein cooperating successively with said channels, each of said recesses having a diflt'erent degree of suction applied thereto, the greatest suction being applied to the recess first encoun tered by a given channel during rotation of the cylinder.
- a suction cylinder having longitudinal channels inclined inwardly of the cylinder and from the radii of the cylinder, said chan nels being subject to suction for a limited period and containing longitudinal part1.- tions extending into the interior of the channels, said partitions having openings therein toward the interior of the channels in order that liquid may flow through said openings during the suction period said partitions acting as traps to hold surplus water from the of the suction cylinder after the
Description
Jan. 7, 1930. R. B. HEYS 1,742,991
su'cnou CYLINDER FOR PAPER MAKING mourns m ram mm Filed Feb. 14, 1929 2 Sheets-Sheet 1 INVENTOR ROLAND BLYTH HEYS qy izz's ziiarlzeje M MM R. B. HEYS Jan. 7, 1930.
SUCTION CYLINDER FOR PAPER MAKING ommas mm was LIKE Filed Feb. 14, 1929 2 Sheets-Sheet 2 INVENTOR ROLAND BLY HEYS @izz's or/z ys Patented Jan. 7, 1930 UNITED STATES PATENT OFFICE ROLAND IBLYTH HEYS, 0F BRISTOL, ENGLAND, ASSIGNOR TUST. ANNES BOARD MILL COMPANY LIMITED, 0F BRISTOL, ENGLAND I SUCTION CYLINDER FOR PAPER-MAKING MACHINES AND THE LIKE Application filed February 14, 1929, Serial No. 939,956, and in Great Britain February 11, 1928.
This invention relates to suction cylinders, or rolls, of machines for making paper, paperboard, mill-board and the like of the type described and claimed in the specification of my 5 U. S. Patent No. 1,591,921, issued July 6th, 1926, hereinafter referred to as the main patent.
According to the main patent, a suction cylinder or roll, which is adapted to abstract moisture from pulp or other material carried by a band passing over part of its periphery, is provided with longitudinal channels, into which the moisture passes and which periodically communicate with a recess or recesses in an end cover or covers connected with a suction device in order to abstract the moisture therethrough, and means are provided for retaining in the longitudinal channels any liquid which may remain there after said channels have passed the recess or recesses in the end cover, or covers, in order to prevent such liquid from wetting the pulp or other material on the next revolution of the cylinder or roll.
provide various improvements in or modifications of the above device.
The present invention consists in an improved suction cylinder or roll of the type described and claimed in the specification of my U. S. Patent No. 1,591,921 in which the suction cylinder or roll is rotated at high speed, and the trailing sides of the longitudinal channels, instead of being substantiall radial, are directed inwardly and rearwar ly behind the radius so as to form pockets, which provide the means for retaining any liquid that may remain in the longitudinal channels after they have passed the said recess, or recesses, said li uid being retained in the pockets due to the hlgh speed of rotation.
The present invention also consists in an improved suction cylinder or roll of the type described and claimed in Patent No. 1,591,921 in which an endless flexible belt (preferably of rubber) running over auxiliary rollers is provided at one or both ends of the suction cylinder or roll, andis adapted to make contact with the suction roll over the arc of its The object of the present invention is to periphery subjected to suction in order to confine the width over which the suction is applied to correspond with the width of the pulp or other material carried by the band.
The present invention also consists in an improved suction cylinder or roll of the type described and claimed in Patent No. 1,591,921 1n which curved or bent strips of metal or other material are inserted into the mouths of the longitudinal channels where the open out on to or towards the periphery of t e suction roll, their curved or bent portions proecting into the channels, and holes beingprovided in the central zones of the curved or bent strips to allow the moisture from the wet pulp to flow therethrough to the inside of the channels, while the curved or bent.
strips will act as traps to prevent excess water befiig returned to the periphery of the suction ro The present invention also consists in an improved suction cylinder or roll of the type described and claimed in Patent No. 1,591,921 in which a plurality of recesses are provided which successively communicate with the said longitudinal channels to abstract moisture therefrom, the amount of suction applied being different for the different recesses.
The present invention further consists in an improved suction cylinder or roll of the type described and. claimed in Patent No. 1,591,921 in which the channels are divided by longitudinal partitions, which extend towards the interior of the channels, and are provided with holes or recesses towards the interior of the channels, so that moisture from the wet pulp ma flow through said holes or recesses during the suction period, but the partitions will act as traps to prevent the excess water being returned to the periphery of the suction rollafter the suction period.
Various constructional forms of the present inventionare' diagrammatica y indicated in the accompanying drawingsi which e Figure 1 is a sectional elevation diagram matically indicating another form of the in vention comp1 ing the widt of the suction area.
ising flexible belts for confin- Figure 7 is a front view of one of the partitions shown in Figure 6.
Figure 8 is a sectional elevation of the improved suction roll shown in Figures 1 and 5, as fitted in a machine in which the pulp carrying band passes over the rear half of the drum.
Referring to Figure 1, the suction cylinder or roll 1 rotates in a clockwise direction as indicated by the arrow and is formed with a plurality of longitudinal channels 2 having trailing sides 3 directed inwardly and inclined rearwardly behind the radii of the cylinder to form pockets. These channels preferably extend substantially parallel with the Y face and-leaves said roll at a axis of the cylinder, but need not necessarily The pulp carrying band 4 enters into contact with the roll at a point 5 on its upper surdownwardly moving point 6 thereof. f
The spaces 7 and 8 (shown dotted) diagrammaticall indicate the positions of end recesses, whic are located in an end plate of the cylinder as in the main patent and which are under suction and with which the longitudinal channels 2 successively communicate.
The apparatus works in the following manner :As the longitudinal channels 2 pass the suction recesses 7 and 8, they are subjected to the action of suction, which withdraws moisture from the pulp 9 carried by the band 4' through holes 10 in the peri heral cover: 27 of the roll and thence throug the longitudinal channels 2. These holes 10 are staggered and register with the channels 2. After each longitudinal channel 2 has left the last suction recess 8, the excess moisture therein is retained in the pocket formed by the trailing side 3 by reason of the high speed of rotation of the roll and due to inertia. Such excess moisture will thereby be prevented from flowing back through the holes 10 in the peripheral cover 27 so as to moisten the pulp on the next ,or any succeeding revolution of the roll.
Preferably the suction applied by the first recess 7 is greater than that applied in the subsequent recess 8 and in consequence thereof there is less tendency to open up. the pulp as it is being dried. More than two suction recesses may be provided, and then the suction applied in the first recess is preferably greater than that appliedin any subsequent recess.
If desired however only one suction recess need be provided.
Referring to Figures 2 and 3, endless belts 11 of flexible material (preferably rubber) are provided at each end of the suction roll 1 in order to confine the width over which the suction is applied to correspond with the width of the pulp or other material carried by the band. These endless belts 11 are shown as passing over auxiliary rollers 12 and 13 which are rotatably mounted upon axles represented by 14 and 15 (see Figure 3).
The endless pulp carrying band 41 is indicated in Figures 1 and 3 and the pulp carrying portion thereof extends across the width 16 indicated in Figure 2. When it is desired to change the width of paper being made the auxiliary rollers 12 and 13 are slid along their axes 14 and 15 in order to vary the width 16 as desired.
If desired only one endless flexible belt may be provided, arranged at one end only of the suction cylinder.
Referring to Figures 4 and 5, a bent or curved strip 18 is inserted into the mouth of each of the longitudinal channels 2 where the said channel opens on or towards the periphery 27 of the suction roll.
The bent or curved portion of the strip projects into the channel 2, and holes 19 are provided in or near the centre of the strip in order to allow the moisture from the wet pulp to flow therethrough to the inside of the channel, when said channel passes the end recesses and is acted upon by suction. After passing beyond the suction recesses, however, the bent or curved strip acts as a trap to prevent excess water being returned to the periphery of the suction roll. 1
Referring to Figures 6 and 7 the longitudinal' channels 2 are divided by partitions 20 extending the length of the channels and towards the interior of the channels. In the drawings each partition consists of a plate 21 with strips 22 bolted or otherwise secured thereto in such a way as to provide holes or open spaces 23 towards the interior of the longitudinal channel. These holes or open spaces 23 act to allow water to pass therethrough when the longitudinal channel is under suction.
After the channel has passed beyond the area where suction is applied, then the parti tion 20 will act as a t1 ap to prevent the escape of moisture from flowing back on to the periphery of the roll.
When intended to be rotated at high speed the paper making machine will be so constructed that this roll will be rotated in the direction of the arrow 24 so that the excess water will tend to collect in the pocket 25 due to the force of rotation of the cylinder and to the inertia of the liquid. The side 28 in Figure 6 is then-the trailing side and isdirected inwardly and rearwardly behind the radius, as shown in the drawing.
In the case of suction rollers rotating at low speed however, the direction of rotation will be as shown by the arrow 26, in which case the pocket 24 will be below the partition 20 after passing the suction applylng area and therefore the excess water will tend to collect therein. The side 28 in Fi re 6 is then the leading side and is directed inwardly and forwardly in front of the radius, as shown in the drawing.
In all the constructions shown the arc of contact between the pulp carrying band and the suction roll may extend from close to the lowest point of the roll to near the highest point. Figure 8 shows for example such an arrangement as applied to the improved suction roll illustrated in Figures 4 and 5. Alternatively said are of contact may extend from close to the highest point of the roll to a downwardly moving point as indicated in Figure 1.
What I claim is:
1. A high speed suction cylinder having longitudinal channels located adjacent its periphery and subject to suction for a limited period, said channels being inclined inwardly and from the radii of the cylinder, forming pockets to catch and retain, by force of rotatation of said cylinder, surplus liquid remaining in said channels after the suction period.
2. A suction device, com rising a rotatable suction cylinder having a jacent its periphery a plurality of longitudinal channels, said channels being inclined inwardly and from ROLAND BLYTH HEYS.
the radii of the cylinder to form pockets, a
cylinder end formed with a plurality of recesses therein cooperating successively with said channels, each of said recesses having a different amount of suction a plied thereto.
3. A suction device, comprising a rotatable suction cylinder having adjacent its periphcry a plurality of longitudinal channels, said channels being inclined inwardly of the cylinder and rearwardly behind the radii of the cylinder to form pockets, a cylinder end formedvwith a plurality of recesses therein cooperating successively with said channels, each of said recesses having a diflt'erent degree of suction applied thereto, the greatest suction being applied to the recess first encoun tered by a given channel during rotation of the cylinder.
4. A suction cylinder having longitudinal channels inclined inwardly of the cylinder and from the radii of the cylinder, said chan nels being subject to suction for a limited period and containing longitudinal part1.- tions extending into the interior of the channels, said partitions having openings therein toward the interior of the channels in order that liquid may flow through said openings during the suction period said partitions acting as traps to hold surplus water from the of the suction cylinder after the
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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GB1742991X | 1928-02-11 |
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US1742991A true US1742991A (en) | 1930-01-07 |
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US339956A Expired - Lifetime US1742991A (en) | 1928-02-11 | 1929-02-14 | Suction cylinder for paper-making machines and the like |
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Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2881668A (en) * | 1956-03-30 | 1959-04-14 | St Annes Board Mill Co Ltd | Paper forming section |
US2881678A (en) * | 1956-06-12 | 1959-04-14 | St Annes Board Mill Co Ltd | Method and apparatus for making paper or paper board or similar fibrous product |
US2888378A (en) * | 1954-11-05 | 1959-05-26 | Milton J Maguire | Paper making machine |
US2893486A (en) * | 1956-02-27 | 1959-07-07 | Crown Zellerbach Corp | Fourdrinier paper making machine |
US2893487A (en) * | 1956-01-06 | 1959-07-07 | Beloit Iron Works | Silencers for suction rolls |
US2900024A (en) * | 1955-10-07 | 1959-08-18 | Scott Paper Co | Silencer |
US3017928A (en) * | 1956-09-26 | 1962-01-23 | Scott Paper Co | Paper machine breast roll |
FR2596433A1 (en) * | 1986-04-01 | 1987-10-02 | Gerland Stowe Woodward Ind Bv | PRESS CYLINDER, IN PARTICULAR FOR REMOVING THE LIQUID FROM A SHEET MATERIAL, SUCH AS PAPER PULP, CONTINUOUSLY PRODUCING, AND PRESS COMPRISING SUCH A CYLINDER |
US20040152574A1 (en) * | 2003-01-31 | 2004-08-05 | Beck David A. | Vented main roll for press assembly in a paper machine |
-
1929
- 1929-02-14 US US339956A patent/US1742991A/en not_active Expired - Lifetime
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2888378A (en) * | 1954-11-05 | 1959-05-26 | Milton J Maguire | Paper making machine |
US2900024A (en) * | 1955-10-07 | 1959-08-18 | Scott Paper Co | Silencer |
US2893487A (en) * | 1956-01-06 | 1959-07-07 | Beloit Iron Works | Silencers for suction rolls |
US2893486A (en) * | 1956-02-27 | 1959-07-07 | Crown Zellerbach Corp | Fourdrinier paper making machine |
US2881668A (en) * | 1956-03-30 | 1959-04-14 | St Annes Board Mill Co Ltd | Paper forming section |
US2881678A (en) * | 1956-06-12 | 1959-04-14 | St Annes Board Mill Co Ltd | Method and apparatus for making paper or paper board or similar fibrous product |
US3017928A (en) * | 1956-09-26 | 1962-01-23 | Scott Paper Co | Paper machine breast roll |
FR2596433A1 (en) * | 1986-04-01 | 1987-10-02 | Gerland Stowe Woodward Ind Bv | PRESS CYLINDER, IN PARTICULAR FOR REMOVING THE LIQUID FROM A SHEET MATERIAL, SUCH AS PAPER PULP, CONTINUOUSLY PRODUCING, AND PRESS COMPRISING SUCH A CYLINDER |
EP0241389A1 (en) * | 1986-04-01 | 1987-10-14 | GERLAND STOWE WOODWARD INDUSTRIES BV Société en nom collectif dite : | Pressure roll, particularly for extracting liquid from a sheet material, such as a continuous web of paperstock, and press comprising such a roll |
US20040152574A1 (en) * | 2003-01-31 | 2004-08-05 | Beck David A. | Vented main roll for press assembly in a paper machine |
US6884323B2 (en) * | 2003-01-31 | 2005-04-26 | Voith Paper Patent Gmbh | Vented main roll for press assembly in a paper machine |
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