US3815645A

US3815645A - Machine cloth for the paper or cellulose industries

Info

Publication number: US3815645A
Application number: US00212350A
Authority: US
Inventors: F Codorniu
Original assignee: Nordiska Maskinfilt AB
Current assignee: Nordiska Maskinfilt AB
Priority date: 1970-12-31
Filing date: 1971-12-27
Publication date: 1974-06-11
Anticipated expiration: 1991-06-11
Also published as: SE355389B; CA943044A; GB1381651A; DE2164700A1; NL7118173A; AU459906B2; AU3753171A

Abstract

A papermaker''s cloth or a cloth for similar purposes having interlacing means at both transverse edges of the cloth in the shape of loops which, when interlocked form a continuous joint in said cloth. The locking loops are formed by weaving the weft yarns in two different layers about one or two temporary threads positioned at the edge or edges of the warp, or alternatively, at the centre thereof, whereby the locking loops will be located entierly between the upper and the lower surfaces of the weave. The loops are thereafter heat treated and the temporary thread removed. The invention also concerns a method of producing said loops.

Description

United States Patent [191 Codorniu MACHINE CLOTH FOR THE PAPER OR CELLULOSE INDUSTRIES [75] Inventor: Francisco Lorente Codorniu,

Halmstad, Sweden [73] Assignee: Nordiska Maskinfilt Aktiebolaget,

Halmstad, Sweden [22] Filed: Dec. 27, 1971 [211 APPENQE, 1 23%,

[30] Foreign Application Priority Data [58] Field of Search 139/20, 383 A, 383, 425 A, 139/408410; 28/72 R; 162/D1G. l, 358, 348

[56] References Cited UNITED STATES PATENTS 1,994,280 3/1935 Hindle 139/383 A 2,041,841 5/1936 Lanz..; 139/20 2,540,874 2/1951 Geddings 139/383 A 2,883,734 4/1959 Draper, Jr 139/383 A 2,903,021 9/1959 Holden et a1. 139/383 A 2,907,093 10/1959 Draper, Jr 139/383 A I 2,949,134 8/1960 Hindle et a1. 139/383 A 3,030,690 4/1962 Mizell 139/383 A [111 3,815,645 [4 1 June 11, 1974 3,139,117 6/1964 Koppelman et a1 139/20 FOREIGN PATENTS OR APPLICATIONS 982,682 2/1965 Great Britain 139/383 A 19,491 1902 Great Britain 139/409 OTHER PUBLICATlONS 325,773, 7-1970, Swedish Publ. Application (Codorniu).

Primary Examiner-James Kee Chi [57] ABSTRACT A papermakers cloth or a cloth for similar purposes having interlacing means at both transverse edges of the cloth in the shape of loops which, when interlocked form a continuous joint in said cloth. The locking loops are formed by weaving the weft yarns in two different layers about one or two temporary threads positioned at the edge or edges of the warp, or alternatively, at the centre thereof, whereby the locking loops will be located entierly between the upper and the lower surfaces of the weave. The loops are there- I after heat treated and the temporary thread removed.

The invention also concerns a method of producing said loops.

1 Claim, 8 Drawing Figures PATENTEUJUHN '91 3.815645,

SHEET 10? 3 PATENTEDJUN 1 1 new. 3.8151345

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3 or 3 MACHINE CLOTH FOR THE PAPER OR CELLULOSE INDUSTRIES BACKGROUND OF THE INVENTION The normal use of cloths for the paper and cellulose industries are in the tubular (continuous) condition. Manufacture of continuous products is in general carried out along two lines: as tubular (circular) fabrics or spliced (jointed) fabrics. The tubular or seamless weaving technique is applied in most cases where the product is to be mounted in a continuous condition. The exception thereto may be when the cloth is too long to be manufactured according to the tubular weaving techinque or when the field of usage is such that the tubular weaving techinque being the more complicated one from a manufacturing point of view, can be avoided without lessening the usability of the cloth. Jointed cloths maybe divided into two groups, viz. those that permit mounting in a continuous condition in the machine but for other reasons are not woven as tubular fabrics, and those that-necessarily must be open (unspliced) during mounting. The former group generally permit jointing to be carried out during the manufacture', giving a joint which in appearance and other characteristics on the whole agrees with the rest of the cloth. The cloths that need be open when delivered to the site of use and subsequently be jointed during mountingmust be provided with locks at both cloth ends. A lock for this purpose .must, however, fulfil the following demands: 1. The lock must be as durable as the rest of the cloth and as resistant against mechanical, chemical and thermal decomposition. 2. The lock parts must be easy to join together during mounting to ensure that the operation standstill is minimized at cloth replacements. 3. It must be easy to form the lock during the manufacture of the cloth proper. 4. In certain fields of usage there are also demands on minimum marking, in additionto which the lock must have the same openness as the rest of the cloth.

The locks most commonly used are those employed for dryer cloths and certain felt cloths, and denominated mechanical locks. These locks constitute so called fastenerlocks similar to those used when splicing driving-belts. The hooks 'aredriveninto the material itself or into separate locking straps which are then mounted on the cloth proper. Such locks are useful for instance for dryer cloths, although they have certain deficiences. In other cloths, for instance those intended for certain felts oras forming wires for the manufacture of fibreboards, locks of this kind cannot be used on account of the excessive marking they cause. For these purposes cloths made from synthetic resin filament yarns, usually monofilaments, are completely prevalent. In these cases the lock is made from loops formed from the samematerial as that making up the cloth or from a separate thread integrated with the cloth. An example of the former lock is disclosed in the Swedish than the joint disclosed in the Published Application No. 322,980, primarily because the weaving thereof cannot be performed until the manufacturer has received a particular order from the user and because the length of the cloth is limited in dependence on the width of the loom.

Although the lock in accordance with the Swedish Published Application No. 322,980 as well as the woven locks may be said to represent the prior art fulfilling all the demands enumerated above, these locks are not quite satisfactory in some positions of use. The reason therefor is that all loops of the kind hitherto known have possessed a maximum dimension exceeding the thickness of the cloth. Consequently, cloths incorporating such loops cannot be used for instance for Kamyr-dewatering cloths, forming wires for cellulose and double wire presses, and several others, precisely on account of the size of the loops. For these and similar positions of use tubular woven products have so far been the only solution. The unavoidable disadvantage is the necessity for the machine designers to install so called cantilever systems in machines of this kind. Systems of this nature naturally imply increased machine costs, costs which are further increased as a result of the machines becoming broader and thus demanding heavier cantilever systems.

I SUMMARY OF THE INVENTION The present invention relates to acloth having a lock which is suitable for use in the positions of use enumerated above andsimilar positions. The lock consists of a number of loops formed alternatingly at the two mutually opposite transverse edges of the cloth from one common thread which also is a part of the longitudinal threads of the cloth (weft threads). The characterising feature of the invention is that the loops are positioned in their entirety between the two planes forming the upper and the lower faces of the cloth. This characterising feature of the invention is obtained, in accordance with apreferred embodiment of the invention, in that two consecutive weft threads at different levels in the cloth are made from one common thread forming a locking loop in the transitional area between the two weft threads. 3 I

When weaving with comparatively rigid yarns, such as monofilaments, thewarp commonly forms sinuous threads in the loom, these threads coiling or twisting about the relatively straight weft threads. As a consequence, the warp will form the surface layers of the cloth and because the warp thread loops in a multileaved weave will not be positioned in a longitudinal row of uniform loop shape the warp cannot form the locking loops in accordance with the inventionn as these will be in a position above at least one of the surfaces of the cloth. It is thus necessary that the locking loops are formed from the weft yarn which, however, on account of its straightness is not very suitable for separate splicing outside the loom. The reason herefor is that an extremely broad joint zone is required to achieve sufficient strength as the straight threads have a low sliding resistance and may be pulled out from the weave fairly easily. To solve this problem the loops are, in accordance with the invention, formed directly in a loomsuch that one and the same thread without interruptions is used to form a series of loops alternatively in the two edges of the cloth while the same thread simultaneously constitutes a longitudinal thread in the finished cloth.

The present invention also concerns a method of manufacturing a cloth having the loops as indicated above.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described more in detail in the following with reference to the accompanying drawings, in which:

FIG. 1 is a vertical transverse section taken in parallel with the extension of the warp threads in a double layer weave,

FIG. 2 is section along line IIII of FIG. 1,

FIG. 3 illustrates on an enlarged scale one marginal portion of the weave provided with the locking loops in accordance with the invention,

FIG. 4 is an end view which in the scale of FIGS. 1 and 2 illustrates the end portions of a weave being manufactured in accordance with the teachings of the invention with locking loops at both ends of the weave,

FIG. 5 is a view similar to the one illustrated in FIG. 4 but on a reduced scale and shows schematically the extension of only those threads of the weave which in the-position of use thereof constitute the longitudinal threads, including the locking loops thereof,

FIG. 6 is a similar view to the one shown in FIG. 4, the locking loops being, however, positioned in the upper cloth of the weave,

FIG. 7 is a similar view to the one shown in FIG. 4 but illustrates the provision of locking loops at both edges of both the upper and the lower cloth,

FIG. 8 illustrates schematically and in a perspective view the course of a weftthread as laid about a border thread to form the locking loops and the extension thereof in relation to one of the warp threads.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT As illustrated in FIG. 1, the cloth comprises

warp threads

1, 2, 3', 4 extending in the plane of the drawing, and

weft threads

5, 6, 7, 8 extending normally relatively the plane of the drawing, divided into two separate layers. The

warp threads

1, 2, 3, 4 consist of sinuous or wave-like threads which are. twisted about the comparatively

straight weft threads

5, 6, 7, 8. If these threads were joined in a manner similar to the one described in the above referenced Swedish Published Application No. 322,980 the result would be that the loops would extend partly beyond the two surfaces 9 and 10 of the wire.

FIG. 2 illustrates the embodiment of the straight weft threads 5, 6 in the sinuously extending

warp threads

1, 2, 3, 4.

In FIG. 3 the two weft threads 5 and 6 comprise one common thread 11 which thread forms the locking loop 12 at the edge of the cloth said loop being positioned entirely between the two

planes

13, 14 forming the surface of the cloth. The locking loops are manufactured at'the same time as the cloth itself, as is illustrated in principle in FIGS. 4 and 5. The

warp threads

1, 2, 3, 4 of the upper cloth and the warp threads 15, I6, l7, 18 of the lower cloth are threaded through the loom comb and reed in the conventional manner. At the far end of one edge, for instance the right one with reference to FIG. 4, is threaded a border thread 19 of the cloth. The result thereof is that the two weft which is coarser than the rest of the threads and preferably consists of a synthetic resin monofilament having a diameter of 2 mm. This single thread is controlled completely individually as compared with the rest of the threads of the warp. During insertion of the first weft thread 5, thread 1 is in lifted position while

threads

2, 3, 4 of the upper cloth and all threads 15, l6, l7, 18 of the lower cloth and border cloth 19 are in lowered position. During insertion of the second weft thread border thread 19 and

threads

1, 3, 4 of the upper cloth are in lifted position while the rest of the threads are in lowered position. The first two weft threads are woven into the upper cloth. The third and the fourth weft threads pass through the lower cloth around the border thread 19 and therefrom pass back through the lower cloth. At the transition between the upper cloth and the lower cloth and vice versa the thread forms a so called turning fold in accordance with the common practice in tubular weaving. I

In accordance with another embodiment represented I in FIG. 6 the border thread 19 has been moved to the centre of the upper cloth. The weft thread passes through one half of the upper cloth, around the border thread and thereafter back through the lower cloth and the second half of the upper cloth, around the border thread and back through thesame half of the upper cloth and the entire lower cloth. As mentioned, the border thread extends in the centre of the upper cloth, and each edge of the cloth consists of saidturning fold known from the tubular weaving technique.

In accordance with a third embodiment illustrated in FIG. 7, two shuttles are used. Two border threads 19" are positioned ateach selvage of the weave. One shuttle passes through the upper cloth, around the left border thread 19 and back through the upper cloth. The second shuttle passes through the lower cloth, around the right border thread 19" and back through the lower cloth. The weave thus comprises two locks. The cloths may be used interconnected or individually. If desired, only one of the cloths may be produced, making use of one shuttle only.

In accordance with all the embodiments referred to, the loops are exposedto a heattreatmentto set them in position before removal of the border thread.

Contrary to the prior art types of locks mentioned in the introduction, the weft threads extend in pairs in planes which are at a right angle relatively the surfaces threads, which together make up the same pair, correspond to one single thread only from the point of view of openness and consequently it becomes possible to double the weft density in a cloth of this kind as compared with for instance a single-layer cloth without impairing the openness. a consequence, the number of loops is likewise doubled and thus the strength greatly improved.

The embodiments illustrated indicate one pattern only but it is evident that the invention is not limited thereto but embraces also other types of weave patterns being within the scope of the appended claims.

What I claim is:

l. A flat woven double layer cloth having surfaces forming two planes and terminating in two transverse edges, having warp and weft threads, for use in the paper making and cellulose industries, particulary as a cloth for dewatering and filtering and as a forming fabric for cellulose and course paper and as a press felt,

adapted for interconnection by means of a locking thread for the purpose of making said cloth endless, and said locking loops being positioned in their entirety between the two surfaces of said cloth.

Claims

1. A flat woven double layer cloth having surfaces forming two planes and terminating in two transverse edges, having warp and weft threads, for use in the paper making and cellulose industries, particulary as a cloth for dewatering and filtering and as a forming fabric for cellulose and course paper and as a press felt, said cloth having the weft threads longitudinal in the position of use, each of said layers having first and second planes of weft threads, locking loops formed by joining respective weft threads of said first plane and said second plane in the two transverse edges of said cloth, said locking loops of said respective layers being adapted for interconnection by means of a locking thread for the purpose of making said cloth endless, and said locking loops being positioned in their entirety between the two surfaces of said cloth.