|Publication number||US3400045 A|
|Publication date||Sep 3, 1968|
|Filing date||Dec 21, 1964|
|Priority date||Dec 21, 1964|
|Publication number||US 3400045 A, US 3400045A, US-A-3400045, US3400045 A, US3400045A|
|Inventors||John B Graham|
|Original Assignee||Kimberly Clark Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (2), Referenced by (5), Classifications (6)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Spt. 3, 1968 a G HAM I 3,400,045
PRESSURE FORMING APPARATUS FOR MAKING PAPER Filed Dec. 21, 1964 5 Sheets-Sheet 1 PRESSURE FORMING APPARATUS FOR MAKING PAPER Filed Dec. 21, 1964 J. B. GRAHAM Sept. 3, 1968 5 Sheets-Sheet 2 J. B. GRAHAM 3,400,045
PRESSURE FORMING APPARATUS FOR MAKING PAPER Sept. 3, 1968 5 Sheets-Sheet 5 Filed Dec. 21. 1964 PRESSURE FORMING APPARATUS FOR MAKING PAPER Filed Dec. 21, 1954 J. B. GRAHAM Sept. 3, 1968 5 Sheets-Sheet 4 PRESSURE FORMING APPARATUS FOR MAKING PAPER Filed Dec. 21, 1964 J. B. GRAHAM Sept. 3, 1968 5 Sheets-Sheet 5 United States Patent Olhce 3,400,045 PRESSURE FORMING APPARATUS FOR MAKING PAPER John B. Graham, Neenah, Wis., assignor to Kimberly- Clark Corporation, Neenah, Wis., a corporation of Delaware Filed Dec. 21, 1964, Ser. No. 419,765 5 Claims. (Cl. 162-317) ABSTRACT OF THE DISCLOSURE My invention relates to papermaking machines and more particularly to such machines of the type in which substantial dewatering of the stock in forming the web is accomplished by applying tension on the forming fabric or wire carrying the paper web to be dewatered as the forming fabric passes about a curved surface.
It has previously been proposed in the application of Charles A. Lee et al. Ser. No. 161,058, filed Dec. 21, 1961 (now Patent No. 3,224,928, issued Dec. 21, 1965), that a paper web may be formed by directing a paper stock slurry between two rolls, which carry a forming Wire, the wire extending over the upper peripheral portion of a first one of the rolls and underneath the second or slice roll for about 180 and the stock being directed on to the portion of the wire bridging these two rolls. A top felt passes around the second roll beneath the wire so that the paper web being formed lies between the wire'and felt 'on this roll, and the web is dewatered primarily by the force of the wire bearing on the roll and on the web and felt caused by the tension of the wire around the roll. The wire-web-felt sandwich is then directed around a third roll having a nip with the second roll and having its center disposed approximately on the same level as the center for the second roll so that the wire-web-felt sandwich is bent in passing around the third roll in the direction opposite to that in which it is bent in passing around the second roll; and, from the third roll, the sandwich passes to a couching position in which the wire and felt separate. The felt carries the formed web from the couching position to various additional dewatering and drying positions.
It is an object of the present invention to provide an improved form of such a papermaking machine in which the wire-web-felt sandwichis not bent reversely from its curved configuration in passing around the slice roll so that under certain conditions a more perfect web may be formed which is not subject to damage by such a reverse bend.
More particularly, it is an object to provide embodiments of the present invention in which Wire-web-felt sandwiches exist only about the slice roll, with the wire being drawn away from the felt on the periphery of the slice roll.
The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects, and such other objects, as will be apparent from the following description of preferred forms of the invention, illustrated with reference to the accompanying drawings, wherein:
FIG. 1 is a diagrammatic elevational view of a paper- 3,400,045 Patented Sept. 3, 1968 making machine including a stock inlet and embodying the principles of the invention;
FIG. 1A is an elevational view on an enlarged scale of the stock inlet; and
FIGS. 2, 3, 4 and 5 are diagrammatic elevational views of papermaking machines constituting modified forms of the invention.
Like characters of reference designate like parts in the several views.
Referring to FIG. 1 of the drawings, the papermaking machine therein illustrated may be seen to comprise a loop of web forming fabric or wire 20 which is disposed about rolls 21, 22, 23, 24, 25, 26, 27, 28 and 29. The fabric 20 is a conventional paper web forming fabric or wire for use in Fourdrinier machines made up of interwoven warp and shute strands for providing drainage openings therebetween through which water may drain from dilute paper stock applied on the fabric. The strands may be either metal or may be of synthetic material in accordance with well known practice.
The roll 21, which is relatively large in diameter in comparison with the other rolls, may be termed a slice roll; and the roll 29, which has its center located on the same level as the center for the roll 21 and which is slightly smaller in diameter than the roll 21, may be termed a breast roll. The roll 22 is a couch roll and has both ends fixed; and the rolls 23, 24, 27 and 28 are simple turning rolls having both ends fixed. The roll 25 may be used as a stretch roll with conventional mechanism (not shown) for simultaneously adjustably moving both ends of the roll and maintaining the fabric 20 taut about the rolls. The roll 26 is a conventional guide roll having one end fixed and the other end movable; and any suitable conventional apparatus (not shown) may be connected with the movable end of the roll 26, so that the roll 26 functions to maintain the fabric loop 20 traveling in substantially the same path about the rolls supporting the fabric. One or more of the fabric supporting rolls, such as the slice roll 21 or the couch roll 22, may be driven for the purpose of driving the fabric 20; so that the fabric passes over the fabric supporting rolls, all of which turn.
It will be observed that the fabric 20 passes over the upper peripheral surface of the breast roll 29 and bridges the rolls 21 and 29, which have a slight gap between them, and then passes under and around the roll 21 covering about of the peripheral surface of the roll 21. The wire 20 then passes in a direct path to the couch roll 22. The fabric 20 passes from the couch roll, beneath the roll 23, over the roll 24, beneath the roll 25, over the roll 26, and over the upper peripheral surfaces of the rolls 27 and 28. Any suitable doctors and Water showers may be used in connection with the fabric 20 and with the rolls supporting the fabric 20, such as the doctors 30, 31 and 32 and the showers 33, 34 and 35. All of the rolls supporting the fabric 20, including the rolls 21 and 29, may be of solid construction as distinguished from bollow, perforated construction, although the roll 22 is preferably provided with narrow circumferential water receiving grooves in its face.
An upper loop of fabric 36 is disposed about rolls 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, and 49; and the fabric 36 also passes over the rolls 22 and 21. The fabric 36 is preferably one that absorbs water to a greater extent and releases water more easily than does the usual water draining web forming fabric and may, for example, be a conventional top felt used by papermakers. The fabric 36 is in direct contact with the exterior surface of the slice roll 21, and the fabric 20 lies on top of or outside of the fabric 36 as the fabric 36 passes over the roll 21. The roll 49 is preferably a suction roll as illustrated.
The roll 40 is a conventional stretch roll having both ends simultaneously adjustably movable by suitable adjusting mechanism (not shown) for maintaining the loop of fabric 36 taut about the rolls supporting the loop. The roll 38 is a conventional guide roll having one end fixed and the other end movable under the control of any suitable control mechanism (not shown) for maintaining the fabric 36 traveling in a predetermined path about the rolls supporting the fabric. The rolls 44 and 46 are pressure rolls, and each of these has a pressure nip with a steam heated Yankee drier 50 of conventional construction. Creping doctors 51 and 52 are provided for ereping paper web from the surface of the Yankee drier 50, the doctors 51 and 52 being alternately so operable. The roll 49 constitutes one roll of a main press 53 which also includes a roll 54 having a pressure nip with the roll 49. A roll 55 is preferably provided in connection with the roll 22 for holding the fabrics 20 and 36 firmly in contact on the surface of the couch roll 22. The other rolls 37, 39, 41, 42, 43, 45, 47 and 48 for supporting the fabric 36 are simple turning rolls. The rolls 44 and 46 are preferably suction rolls as illustrated.
A third fabric loop 56 passes between the rolls 49 and 54. The fabric 56 is prefer-ably a bottom felt conventionally used in papermaking. The fabric 56 passes around rolls, 57, 58, 59, 60, 61, 62, 63 and 64, in addition to the roll 49. The roll 64 constitutes one roll of a wringer 65 which includes also another roll 66 held to have a pressure nip with the roll 64. The roll 62 is a conventional guide roll having one end fixed and the other end movable under the control of a suitable control mechanism (not shown) for maintaining the fabric 56 traveling in a predetermined path about the rolls supporting the fabric. The roll 59 is a conventional stretch roll having both ends simultaneously adjustably movable by suitable adjusting mechanism (not shown) for maintaining the loop 56 taut about the rolls supporting the loop. The other rolls 57, 58, 60, 61 and 63 are simple turning rolls.
A stock inlet 67 is provided for directing paper stock between the rolls 29 and 21 and particularly on to the portion of the fabric 20 that bridges the narrow gap between the rolls 21 and 29. The inlet 67 comprises a manifold 68 (see FIG. 1A) and a pair of plates 69 and 70 which have facing, parallel, fiat surfaces defining an elongated slot 71 between them. It will be observed from FIGS. 1 and 1A that the slot 71 is vertically disposed so as to direct stock directly into the nip between the rolls 21 and 29.
In operation, paper stock slurry is supplied to the manifold 68, and the paper stock passes into the slot 71 and discharges from the lower ends of the plates 69 and 70 into the gap between the rolls 29 and 21 and on to the portion of the wire 20 bridging the gap between these rolls. The plates 69 and 70 may, for example, be 8 inches to 30 inches long and may be spaced less than an inch apart, such as /8 inch to /3 inch, so as to impart a fine scale turbulence to the stock passing between them, in accordance with the teachings in the copending application of David W. Appel et al., Ser. No. 278,521, filed May 2, 1963. The paper stock starts to drain immediately on contact with the wire 20; and the stock passes, as it forms into a web, around the roll 21, being disposed between the felt 36 and the wire 20. The web in passing around the roll 21 in a sandwich between the wire 20 and felt 36 is dewatered primarily due to the force with which the wire bears on the roll 21 and on the web and felt 36 because of the tension maintained on the wire around the roll, although centrifugal force also helps in this respect. The web continues along with the wire 20 and felt 36 to the rolls 22 and 55. The wire 20 separates from the felt 36 at this point, and the paper web continues with the felt 36, traveling on the underside of the felt. The web follows the felt 36 rather than the wire 20 at this point, since the felt is considerably more dense than the wire.
The felt and web travel through the main press 53, and the press 53 is effective to press some of the remaining water from the web traveling on the underside of the felt, and this dewatering action is augmented by the bottom felt 56 which functions to absorb water from the web as the web passes through the main press. The felt 36 continuing to carry the web on its under surface passes around the rolls 48 and 47 to the pressure roll 46, and the web transfers from the felt 36 on to the drier drum 50 in the nip between the roll 46 and the drum 50. As the drum 50 rotates, the web is carried on the outer surface of the drum 50 through the nip between the pressure roll 44 and the drum50, and the pressure roll 44 also has a dewatering action on the web and causes sure adherence of the web on the drum 50. The web in traveling with the drum 50 to the doctor blades 51 and 52 is dried, and one or the other of the blades 51 and 52 doctors the web from the drum 50. The web is then reeled into rolls by any suitable reeling equipment (not shown).
It will be observed that the felt 36 between the roll 21 and the web couching line between the rolls 22 and 55 has no reverse bends in it; that is, the felt 36 does not'pass around any roll or any other support that has the function of bending the felt in a direction opposite to that in which it is bent in passing around the roll 21. The sandwich of the wire 20, the web, and the felt 36 thus is not disturbed in passing from the roll 21 to the couching line between the rolls 22 and 55, and a relatively perfect sheet is thus formed.
The principal difference between the embodiment of the invention illustrated in FIG. 2 and that illustrated in FIG. 1 is that the stock inlet is disposed to direct stock horizontally rather than vertically and the wire covers about 180, rather than of the periphery of the slice roll. Parts in the FIG. 2 embodiment which are similar to those in the FIG. 1 embodiment are designated by the same reference characters except with the sufiix a added. A slice roll 21a is utilized, and the inlet 67a directs the stock horizontally and to a place directly above the center of rotation of the roll 21a.
The FIG. 2 embodiment includes a forming fabric 72, which is similar to the fabric in the first embodiment, except that it is of different length. The fabric 72 extends around slightly more than of the slice roll 21a and around a roll 73 which is smaller in diameter than the slice roll 21a and is positioned above the roll 21a. The forming fabric 72 extends also about the rolls 22a to 28a. It will be observed that there is a small gap between the rolls 73 and 21a and that the forming fabric 72 bridges this gap. The paper stock inlet 67a is positioned to discharge stock horizontally and between the rolls 21a and 73 and on to this portion of the forming fabric bridging the gap between these rolls.
A felt 74, which is similar to the felt 36 except that it is a different length, extends around the roll 21a for more than 180 of its periphery. The felt 74 also extends around simple turning rolls 75, 76 and 77, also about rolls 38a to 48a corresponding to the similarly numbered rolls in the first embodiment, also between rolls 54a and 49a corresponding to the rolls 54 and 49 and between rolls 22a and 55a corresponding to the rolls 22 and 55. A bottom felt 56a is utilized, and this extends around rolls 57a to 64a and about the roll 49a and through the nip between the press rolls 54a and 49a.
In operation, paper stock is discharged horizontally from the inlet.67a between the rolls 73 and 21a. The formation takes place on the wire 72, and the web is dewatered as it passes around the slice roll 21a positioned between the wire 72 and felt 74 primarily due to the tension maintained on the wire 72. The web then proceeds through the remainder of the papermaking machine similarly as in the first described embodiment. This form of the invention provides more forming length for the paper web, since the wire 72 lies on the slice roll 21a for about 180 instead of about 90; and hence this form is better suited for heavy weight webs than is the first form of the invention.
The modified form of the invention illustrated in FIG. 3 is basically the same as that shown in FIG. 1, except that the rolls 22, 23, 24 and 55 have been dispensed with, and a wire supporting roll 78 is utilized instead of the wire supporting rolls 22, 23 and 24. Parts in the FIG. 3 embodiment have been given reference numerals corresponding to similar parts in the FIG. 1 embodiment, ex cept with a sulfix b added to each reference numeral. An endless forming wire 79 similar in construction to the fabric 20 but shorter in length is used, and the wire 79 extends from the roll 29b around the slice roll 21b and around the roll 78 to the rolls 25b, 26b, 27b and 28b. The roll 78 is smaller in diameter than the roll 21b and is positioned below the roll 21b, with its center offset toward the drier end of the machine with respect to the center for the roll 21b, so that the wire 79 leaves the surface of the roll 21b on a line 80 on the bottom of the roll 21b, whereby'the wire 79 is supported by the roll 21b for approximately 90 of the circumference of the roll 21b.
The felt 81 is similar to'the felt 36 and is supported by the same rolls except that the felt passes directly from the roll 21b to the press roll 49b. Since the pass of the felt 81 from the roll 21b lies above and is more upwardly directed than is the pass of the wire 79 from the roll 21b to the roll 78, the felt 81 leaves the surface of the roll 21b along a line 82 which is close to but is spaced from the line 80 on the periphery of the slice roll 21b.
The FIG. 3 embodiment functions much the same as the FIG. 1 embodiment except that the wire 79 is separated from the felt 81 and the paper web carried by the felt 81 while the felt 81 is still in contact with and is supported by the slice roll 21b. Therefore, there is no wire-web-felt sandwich except on the cylindrical surface of the slice roll 21b, and no such sandwich has been changed from a cylindrical form on the roll 21b to a planar form as it exists between the rolls 21 and 22 in the first embodiment. Therefore, even less disruption of the web can be expected using the FIG. 3 embodiment than with the FIG. 1 embodiment; since the wire-web-felt sandwich, when it exists, has the constant cylindrical form of the roll 21b.
The embodiment illustrated in FIG. 4 differs mainly from the FIG. 2 embodiment in eliminating the rolls 22a and 55a and the contacting portions of the forming wire and felt between the rolls 21a and 22a. In these respects, the FIG. 4 form is also similar to the, FIG. 3 form. A
number of parts which are similar to parts described in previously described embodiments are utilized, and these are designated by the same reference characters except that it is of different length, and the wire 83 extends around the rolls 73c and 210. A roll 84 is provided beneath the roll 21c. The roll 84 is smaller in diameter than the roll 21c and has its center approximately below the center of the roll 21c. The forming fabric extends from the roll 21c around the roll 84 and from thence around rolls 25c to 280. A felt 81c is provided which is similar to the felt 81 in the FIG. 3 embodiment and is supported by similar rolls.
The rolls 84 and 210 have the wire 83 and felt 81c passing between them, together with the formed paper web therebetwen, and the roll 84 may either be positioned to have a pressure nip with the roll 21c, or the roll 84 may be positioned downwardly slightly to provide a small gap between the rolls 84 and 210 so that no pressure exists on the wire and felt as they pass between these rolls. If the roll 84 is positioned to have a pressure nip with the roll 210, the roll 84, in this case, should preferably have an open construction on its peripheral surface, that is, it should either be a solid roll provided with small circum- 'ferential grooves or else the roll should be hollow with a drilled periphery.
In operation, the paper stock is directed into the gap between the rolls 73c and 21c and on to the portion of the wire 83 that bridges this gap. A paper web is thus formed on the wire and travels between the wire '83 and felt 810 for about 180 around the roll 21c. The wire 83 in forcefully bearing on the slice roll 21c is effective for dewatering the web in its travel around the roll 21c; and, assuming there is no pressure nip between the roll 84 and roll 210, the paper web is drawn from the wire 83 and follows the felt 81c quite similarly to the action of the felt 81 in the FIG. 3 embodiment in transporting the web from the slice roll 21b. The paper web is dewatered in the main press 53c and is transferred on to the drier 50c as with prior embodiments. If the roll 84 is positioned to have a presure nip with the roll 21c, these rolls provide a dewatering action on the paper web as it passes through this mp.
The embodiment of the invention illustrated in FIG. 5 is quite similar to that illustrated in FIG. 4 but mainly differs from it in that the forming fabric travels only over 90 of the slice roll instead of 180, and the bottom felt is run in contact with the top felt and slice roll as well as through the nip of the main press. The FIG. 5 embodiment includes parts similar to parts in prior embodiments, and these are designated with the same reference characters with the additional d suffix. This embodiment includes the forming fabric .85 which is similar to the fab- 'ric 20, except that it is of different length. The fabric 85 passes over the rolls 73d and 21d and over an additional roll 86 which is positioned below the roll 21d such that there is a stretch 85g of the fabric 85 extending approximately vertically and downwardly from the portion of the periphery of the roll 21d which is most remote from the drier end of the machine. The wire 85 extends around substantially 'of the periphery of the slice roll 21d, since the roll 73d has its center disposed approximately above the center of the roll 21d and since the stretch 85g of the wire 85 is nearly vertical. The fabric 85 also extends around rolls 25d to 28d. A felt 81d is used, and this extends over the roll 21d for about 225 on the periphery of the roll 21d, leaving the roll 21d on its bottom; and the felt extends also over the rolls 75d to 77d and rolls 38d to 49d, similarly to the felt 810 in the FIG. 4 embodiment.
A bottom felt 87 is utilized, and this is similar to the felt 56 except that it is of greater length. The felt 87 extends over the roll 49d and rolls 57d to 64:2, similarly to the felt 56; in addition, the felt 87 extends over rolls 88. 89 and 90. The rolls 88 and 90 are simple turning rolls. The roll 89 has its center positioned below the center of the slice roll 21d and is a suction roll and provides a pressure nip with the roll 21d so as to form a press with the slice roll 21d.
In operation, the stock inlet 67d discharges stock into the open nip between the rolls 73d and 21d and on to the portion of the wire 85 bridging the gap between the rolls. A paper web is thus formed on the wire 85 and is positioned between the wire and the felt 81d as they pass about the roll 21d. The web is dewatered .due to the tension on the wire 85 as the web passes around the roll 21d with the wire and the felt, and the wire leaves the felt and web on a line 91, which is substantially on the same level as the center of the slice roll 21d. The web and felt continue around the roll 21d to the nip between the rolls 21d and 89, and the felt 81d and web travel directly from this nip to the roll 49d, with the web adhering to the bottom surface of the felt 81d. The press, including the rolls 21d and 89 and the bottom felt 87 passing through the nip between the rolls 89 and 21d, helps in dewatering this web; and the web is further dewatered and dried in passing through the main press 53d and on to the drier drum 50d, as in previously described embodiments.
The papermaking machines of the invention advantageously form a paper webbetween a felt and a forming 7 wire, and each includes a slice roll about which'the felt and wire pass with the wire being exterior with respect to the felt. A breast roll is provided in close proximity but spaced from the slice roll, so that the wire bridges the gap between the two rolls; and paper stock projected into this gap on to the wire forms a paper web that lies between the felt and the wire asthey pass about the slice roll. Dewatering of the paper web in the wire-web-felt sandwich passing around the slice roll occurs due to the tension applied to the wire causing it to forcefully bear on the slice roll and squeeze the paper web between the felt and wire. Centrifugal force on the water within the web being formed alsohelps in this respect but is effective particularly in removing the water from the wire once the water has been squeezed from the paper web due to the tension on the wire.
In order to provide a substantial forming length in the felt-wire sandwich supported by the slice roll, the wire preferably extends around the slice roll from 90 to'180". Depending on the consistency of the stock supplied between the slice and breast rolls, the speed of the machine, the gap between the slice and breast rolls, the speed of the stock discharged from the associated inlet, the tension of the forming wire, the diameter of the slice roll, and other factors, the forming length of the felt-wire sandwich varies in length. The forming length is that length from the transverse line on the wire at which stock is'applied on to the wire to the line on the wire about the slice roll at which a discrete paper web appears. It will therefore be understood that for thicker basis weights, the arc of the wire-felt sandwich about the slice roll of about 180 is preferred. Such an arc occurs in the embodiments shown in FIGS. 2 and 4. For lighter basis weight webs, such as for tissue, the 90 arc of the wire and felt included in the other embodiments is entirely adequate.
It may be mentioned, incidentally, that within the forming length of the wire and felt, the stock being formed into the web has a substantially constant pressure and that the forming length is self-adjusting; that is, it increases automatically with increased web basis weight and machine speed, for example. The consistency and velocity of the stock, the gap between the breast and slice rolls, the speed of the machine and other factors are, of course, properly adjusted so that there is no back-flow of the stock from between the breast and slice rolls, and the felt-wire sandwich on the slice roll accepts all of the stock supplied.
In order that there may be a minimum of disturbance of the web after initial dewatering in the felt-wire sandwich about the slice roll, the machine arrangements of the invention are such that the wire-web-felt sandwich is not given any reverse bends; that is, bends in a direction opposite to that which the sandwich has in passing around the slice roll, before the web is removed from the wire and is carried by the felt for subsequent additional dewatering and drying. In the FIG. 1 and FIG. 2 embodiments, the wire-web-felt sandwich passes directly, in a straight line, from the slice roll to a couching roll at which the felt and wire separate. The FIG. 1 embodiment provides about 90 of travel of the wire about the slice roll, and the FIG. 2 embodiment provides about 180 of travel about the wire of the slice roll. The other embodiments, namely, those shown in FIGS. 3, 4 and 5, advantageously do not provide any type of wire-web-felt sandwich subsequent to the slice roll. In the FIG. 3 embodiment, the wire 79 travels over only one of the lower quadrants, of the slice roll 21b, while the wire 85 in the FIG. embodiment is so arranged that it travels over only 'roll'21c of about 180.
I wish it to be understood that the invention is not to be'limited to the specific constructions and arrangements shown and described, except only insofar as the claims may be so limited, as it will be understood to those skilled in the art thatchanges may be made without departing from the principles of the invention.
What is claimed is:
1. In a paper web forming machine, the combination of an endless paper web forming fabric having interstices therethrough for draining paper stock deposited thereon, an endless felt, means for supporting and-moving said fabric and also said felt each in the form of a loop and including a plurality of supporting rolls, said rolls including a slice roll and both said fabric and said felt passing around it with a substantial arc of at least with said fabric being outermost and including a second roll disposed adjacent to and in proximity to said slice roll and having said fabric passing around it and bridging to said slice roll, and a paper stock inlet arranged to direct the stock between said slice and second rolls so that the stock drains through said fabric to form a paper web between said fabric and said felt which passes around said slice roll, said supporting means including a third roll which is substantially spaced from said slice roll and is in such position that said felt passes from said slice roll to said third roll in a straight pass.
2. In a paper web forming machine as set forth in claim 1, said third roll also supporting said fabric in addition to said felt so that both said fabric and said felt pass from said slice roll in a straight pass to said third roll and so that said fabric separates from said felt on said third roll with the paper web continuing to follow along with said felt.
3. In a paper web forming machine as set forth in claim 1, said supporting means also including a fourth roll which supports said fabric and is so positioned that the fabric travels from said slice roll to said fourth roll and leaves said slice roll on the periphery of the slice roll along a'line which precedes the line at which said felt leaves said slice roll during the rotation of the slice roll. 4. In a paper web forming machine as set forth in claim 1, said supporting means also including a fourth roll which supports said fabric and around which said fabric travels-and which has a pressure nip with said slice roll so that said fabric and said felt separate at the nip of said fourth roll and slice roll.
5. In a 'paper web forming machine as set forth in claim 3, said supporting means also including a fifth roll having a pressure nip with said slice roll positioned about the periphery of the slice roll so that said felt exclusive of said fabric passes through said nip, and a second endless felt passing through said nip along with said first named felt for removing water from the paper web which is carried by said first named felt. 1
References Cited I, UNITED STATES PATENTS 3,224,928 12/1965 Lee et al 162-417 3,325,745 6/1967 Graham 1 62317 DONALL SYLVESTER, Primary Examiner.
A. C. HODGSON, Assistant Examiner.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3224928 *||Dec 21, 1961||Dec 21, 1965||Kimberly Clark Co||Papermaking machine using a moving felt through a pressure forming slice and the same felt throughout the machine|
|US3326745 *||Dec 4, 1964||Jun 20, 1967||Kimberly Clark Co||Apparatus for forming paper between a forming wire and felt|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3625814 *||Jun 13, 1969||Dec 7, 1971||Allis Chalmers Mfg Co||Multilayer papermaking machine with impervious roll web former|
|US3876498 *||Sep 14, 1973||Apr 8, 1975||Beloit Corp||Controlled forming wire separation on impervious roll of twin-wire papermaking machine|
|US4102737 *||May 16, 1977||Jul 25, 1978||The Procter & Gamble Company||Process and apparatus for forming a paper web having improved bulk and absorptive capacity|
|US6398916 *||Dec 16, 1999||Jun 4, 2002||Valmet Karlstad Ab||Simplified through-air drying paper making machine having a twin wire forming section|
|EP1245727A1 *||Mar 26, 2001||Oct 2, 2002||A. CELLI S.p.A||Machine and method for producing a sheet of paper material|
|U.S. Classification||162/317, 162/301, 162/214|