US2983986A

US2983986A - Papermker's felt

Info

Publication number: US2983986A
Application number: US811421A
Authority: US
Inventors: Howard M Helland
Original assignee: LOCKPORT FELT Co
Current assignee: LOCKPORT FELT Co
Priority date: 1959-05-06
Filing date: 1959-05-06
Publication date: 1961-05-16
Anticipated expiration: 1978-05-16

Description

May 16, 1961 H. M. HELLAND 2,983,986

PAPERMAKER S FELT Filed May 6, 1959 FIG.4

`\\\\ INVENTOR:

HO'WARDMHELLAND Patented May 16, 1961 ,Unite States Patent @me 2,983,986 PAPERMAKERS FELT Filed May 6, I1959,' ser. N. 811,421 1 '7 cli'msgicl. asi-17s) p This invention relatesto a structurally improved papermakersfelt, such as for `use Iforvexample in the manufacture'ofpaper, paper board, pulp, and similar items suclfasf` for ,example asbestos shingles, Transite pipes, and" like products. vMore speciiically, the invention relatesto` improvements infthe art, referred to in my pre- 'viously filed `applicationsy Serial No. 743,624, filed lune 23, 1958,' and SerialNo; 756,405, iiled August 2.1, 1958. I It is a primary object of the presentinvention to provide an improved papermakers felt constructed of any oftheconventionally used grades of wool, cotton, or other natural or synthetic fibres or combinations thereof; so fabricated as to provide a papermakers felt, which at the same time possesses optimum lateral balance and resstance to longitudinal curl, and is of high bulk characteristics. l j l Another object ofthe invention is to provide a felt as aforesaid which presents a smooth working surface of improved p ulp supporting andv cushioning' characteristics. Another object is Vto provide a felt as aforesaid which isv eiiicient as` a `drainage iilter in its intended use. Still another object is to provide an improved felt as aforesaidv whichis of ldesirable strength in the direction ofthe feltfloadandwhicli' also inherently possesses improvedf dimensional stability characteristics. f ffOthei' A'objects'and advantages of the invention will appear-,fronrthe specification hereinafter, and the accompanying drawings wherein: A Fig. l is a diagrammatic perspective View of one form of plied yarnlsuch' as maybe employed in construction of afelt of the` present invention; Fig. 2 isa planiview (at reduced scale) of a laterally distorted swatch` of fabric, illustrating the braid pattern employed in thernanufacture of the felt, the yarnsbeing shown `as variouslyfcolored to facilitate reading the drawing; f l Fig. 3 is a plan view corresponding to Fig. 2 but of a swatch of the fabrication as it actually appears subsequent to initial braiding thereof; and Fig. 4 is a diagrammatic fragmentary 'sectional view taken along line IVl-IV of Fig. 2.4

z' In the papermakerswetfelt art it is a prime object to provide a' fabric structure which is of high bulk characteristics yet longitudinally strong, comprising an eiiicient water-'drainage or iilter membrane. For such purposes the lwool and/ or other fibres used must be so integrated as ytopr'esent to the pulp being treated a uniformly s'moothandfle'vel yet resilient surface. The present in- Vention provides the vabove stated objects through use of a novel fabrication of yarns whereby the individual fibres subsequentv to the yarn interlocking operation remain free to move relative to one another during the fabricr n systems, and may be either singles or plied" yarns.

In fabricating a felt of the present invention either a singles yarn ora conventional plied yarn may be employed. Or, as still another alternative, as a separate operation, Va plurality of singles .yarns made with a singles twist such as the pair of yarns 10-1'2 shown in Fig. l may be' plied as by means of a neutralizing Z twist. Hence, the resultant plied yarnv designated generally at 14 comprises intertwined singles yarns, the individual iibres of which are as near as possible untwisted. V.By way of a specic example, the card roping may be initiallydrafted and S twisted at the rate for example of 4.0 t.p.i. (twists per inch), depending upon the fibre lengths and other variables. The two singles yarns so produced may then be relatively entwined by means of a neutralizing Z twist in such manner as to provide a plied yarn for example of 4.5 t.p.i. Approximately this ratio of singles and plied yarn twists will rev stock 14 as explained hereinabove.

sult in production'of a plied yarn as indicated at 14 in the drawing wherein the individual libres are only very slightly twisted (in `one direction or the other) or are substantially untwisted aboutv their own axes, while gently winding spirally about the neutral axis of the yarn.

-In the alternative, the card roping may be initially formed into singles yar-n stock by means of a Z twist operation, and the singles yarns may thereupon be S twisted into plied yarn form, to provide the plied yarn In either case the yarn stock may be described as comprising two groups of untwisted fibres gently rolling around vone another. Due to the fact that the singles yarns are relatively entwined the overall structure of the plied yarn 14 has adequate strength to withstand the subsequent braiding operation, in spite yof thefact that the individual fibre are substantially untwisted.

Asr the second step in the manufacture of the felt of the present invention, pluralities of the yarns 14 are intertwined as shown in Fig. 2.` The construction is illustrated herein as when being laterally stretched out of its natural se condition, to facilitate understanding the nature of the yarn interweaving system. When the structure is relaxed its longitudinal resiliency causes it to return to its normal condition as shown in Fig. 3 and it will be noted that the yarns14 are interlinked and nested together in a manner quite unique in the wet felt art. Each plied yarn member of the system runs generally longitudinally of thebelt into which the fabric is made, although it follows a slightly zig-zag course. To facilitate reading the Vdrawing some of the yarns are darkly colored as indicated at 16 in Figs. 2, 3. It will be seen that along each leg of the zig-zag course each yarn passes rst over two adjacent yarns and then reverses course and passes under the same two yarns. yIt then reverses course again and passesover the same two yarns, but then continues on the same course and passes under two more yarns. It then reverses course and passes over the two last mentioned yarns, whereupon it reverses again and passes under the two last mentioned yarns; and so on throughout the length of the fabrication. In my prior application Serial No.` 743,624 referred to hereinabove, each yarn passes either over or under all of the adjacent yarns throughout each leg of its zig-zag course, and in application Serial No. 756,405 each yarn passes first over two yarns and'then u nder two yarns, and then reverses course and passes under two yarns and then over, and so on. Thus the constructions are substantially different.

Subsequent to braiding, the fabric is submitted to any suit-able shrinking and fulling orlmillingf operations;-

and thus the `fabric isV shrunk and fulled as into the 3 form illustrated by Figs. 3-4. As shown in Fig. 3, the yarns 14 are substantially straightened out in plan view to their conditions of maximum eiciency with respect to resistance to tension loads on the felt. It will of course be understood that the fabric of the invention may be constructed by any suitable type machine.

Whereas, the yarns 14, due to their relatively entwined positions in the interlock pattern acquire optimum felt tension resistance characteristics, the locally soft nature of the yarn stock permit them to easily deform and bulk out and respond in improved manner to the fulling treatment because the individual fibres thereof are of improved mobility. Hence, in the resulting lfelt fabrication the fibres provide a mat of superior surface smoothness and cushioning characteristics. At the same time the double thickness and laterally unrestrained nature of the interlock pattern permits the fabric to breathe and to operate with maximum efficiency in accord with the phenomenon of capillarity and in response to the pumping action within the felt when passing through compression rolls; thereby improving its water removing abilities. For the same reason the fabric is of improved inherent selfcleaning characteristics and is more responsive to conventional cleaning devices than are felts of other construction. Thus, each fibre of the fabrication is disposed to act more eiciently in its assigned task.

By virtue of the more efficient bulking of the fibres in the felt of the invention, it is of superior surface or finish characteristics. It is a feature of this invention that in the finished felt belt the individual yarns and fibres are disposed at angles only slightly oblique to the direction of Ibelt travel (Fig. 3); thereby providing a felt of increased total load pulling power for the same felt weight, and avoiding head-on impacts of yarn rises or floats against stationary equipment such as suction boxes, cleaning shoes, etc.

' It is a particular feature of the present invention that by virtue of the braid pattern of the yarns a belt (such as a papermakers felt) made from this fabric is laterally balanced and does not tend to curl up in the direction of its yarns. Hence, the felt is inherently balanced and tends to ride true on the rollers of the paper making machine. At the same time the fabric yarns retain their optimum bulk characteristics, as explained hereinabove. Thus, it will of course be appreciated that the invention is not limited to the precise construction illustrated herein nor to the specific wet felt usage described hereinabove, and that the construction may be modified such as 4for example by interlacing each yarn any other desired number of times with adjacent yarns along each short general course before reversing course into a long general course, without departing `from the spirit of the invention or the scope of the appended claims.

I claim:

1. A new papermakers felt belt for supporting and draining paper making material, said belt comprising a felt-like fabric structure having only substantially untwisted yarns running generally parallel and lengthwise of the belt with adjacent yarns interlocked by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course lengthwise of the belt, each yarn member passing lalong each leg of the zig-zag course first over two adjacent yarns of adjacent courses, and then reversing to pass under the same two yarns; again reversing course and passing over the same two yarns and then passing under paired adjacent yarns while continuing on the same course, whereupon it again reverses course and repeats the aforesaid pattern, the individual fibres of said yarns being spirally wound but substantially untwisted about their own axes, said yarns each comprising card roping twisted only slightly into twisted yarn form, said fabric being fulled.

2. A new papermakers felt belt for supporting and draining paper makingv material, said belt comprising a felt-like fabric formed` solely of relatively soft twisted yarns running lengthwise thereof in side-by-side relation and interlocked by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course lengthwise of the belt, each yarn member passing along each leg of the zig-zag course first over two adjacent yarns of adjacent courses, and then reversing to pass under the same two yarns; again reversing course and passing over the same two yarns and then passing under paired adjacent yarns while continuing on the same course, whereupon it again reverses course and repeats the aforesaid pattern, the individual fibres of said yarns being substantially untwisted about their own axes, said fabric being fulled.

3. A new papermakers felt belt for supporting and draining paper making material, said belt comprising a felt-like structure having only substantially untwisted plied warp yarns running generally parallel and lengthwise thereof with adjacent yarns interlocked by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course lengthwise of the belt, each yarn member passing along each leg of the zig-Zag course first over two adjacent yarns of adjacent courses, and then reversing to pass under the same two yarns; again reversing course and passing over the same two lyarns and then passing under paired adjacent yarns while continuing on the same course, whereupon it again reverses course and repeats the aforesaid pattern, the individual fibres of said yarns being spirally wound but substantially untwisted about their own axes, said plied yarns each comprising a pair of singles yarns each comprising card roping twisted into conventional S twisted yarn form and Z twisted together in opposite direction into plied yarn form, said interlocked yarns being fulled.

4. A new papermakers fabric belt for supporting and draining paper making material, said belt comprising a felt-like structure having relatively soft twisted warp plied yarns running lengthwise thereof in side-by-side relation and interlocked by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course lengthwise of the belt, each yarn member passing along each leg of the zig-zag course first over two adjacent yarns of adjacent courses, and then reversing to pass under the same two yarns; again reversing course land passing over the same two yarns and under paired adjacent yarns while continuing on the same course, whereupon it -again reverses course and repeats the aforesaid pattern, the individual libres of said yarns being substantially untwisted about their own axes, said yarns each comprising a pair of singles yarns twisted together into plied yarn form, said fabric being fulled.

5. A new papermakers felt fabric for supporting and draining paper making material, said fabric comprising a structure of relatively soft-twisted plied yarns running lengthwise thereof in side-by-side relation and interlocked by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course lengthwise of the fabric, each yarn member passing along each leg of Ithe zig-zag course first over adjacent yarns of adjacent oourses, and then reversing to pass under the same two yarns; again reversing course and passing over the same two yarns and under paired adjacent yarns while continuing on the same course, whereupon it again reverses course and repeats the aforesaid patern, said yarns having their individual fibres substantially untwisted about their own axes and each comprising a pair of singles yarns S twisted together into plied yarn form, each of said single yarns comprising card roping Z twisted in opposite direction into singles yarn form, said fabric being fulled.

6. A papermakers felt for supporting and draining paper making material, said felt comprising a fabric structure having plied yarns running lengthwise thereof in sideaby-side relation and interlocked by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course` lengthwise of the belt, each yarn member passing along each leg of the zig-zag course rst over adjacent yarns of adjacent courses, and then reversing to pass under the same two yarns; again reversing course and passing over the same two yarns and under paired adjacent yarns while continuing on Ithe same course, whereupon it again reverses course and repeats the aforesaid patern, said yarns each oomprising a plurality of singles yarns twisted together cinto plied yarn form, each of said singles yarns comprising card roping twisted into yarn form, said fabric being fulled.

7. A new papermakers felt for supporting and draining paper making material, comprising a fabric structure having only warp yarns, said warp yarns running lengthwise of the fabric and in side-by-side relation, each warp yarn being intenlocked alternately with yarns adjacent thereto by means of a braiding pattern disposing each yarn member to follow a slightly zig-zag course lengthwise of the belt, each yam member passing along References Cited in the le of this patent UNITED STATES PATENTS 897,551 Lundgren Sept. 1, 1908 1,497,068 Collingbofurne June 10, 1924 2,423,828 Chagnon July 15, 1947 OTHER REFERENCES Eifect of Ply Twist on Single Twist from Textile World, February 21, 1931, page 38. Copy in Class 57- 139, Div. 21.