US3779286A

US3779286A - Method and apparatus for weaving terry cloth

Info

Publication number: US3779286A
Application number: US00294207A
Authority: US
Inventors: E Pfarrwaller
Original assignee: Sulzer AG
Current assignee: Sulzer AG
Priority date: 1972-10-02
Filing date: 1972-10-02
Publication date: 1973-12-18
Anticipated expiration: 1990-12-18

Abstract

The terry cloth weaving machine is provided with a means to vary the length of cloth travel downstream of the temples so as to maintain the fell straight. In one embodiment, a deflecting element is positioned between the breast beam and draw-off roller to deflect the cloth out of its normal path during reciprocation of the breast beam. In another embodiment, a vertically-reciprocal roller is mounted between the temples and breast beam to deflect the cloth.

Description

O Umted States Patent 1 1 1111 3,779,286

Pfarrwaller Dec. 18, 1973 [5 METHOD AND APPARATUS FOR WEAVING 607,377 7/1898 Hutchins 139/25 TERRY CLOTH 1,737,688 12/1929 Ryon 139/25 3.331 402 7/1967 Kathriner et =11... 139/291 Inventor: Erwin Pfarrwaller, Wimerthur. 3,428,095 2/1969 Pfarrwaller 1. 139/25 Switzerland [73] Assignee: Sulzer Brothers Ltd., Winterthur, Primary Emminer Henry S. Jaudon Swltzerland A!mrne vHugh A. Chapin et al.

[22] Filed: Oct. 2, 1972 Appl. No.: 294,207

Foreign Application Priority Data Oct. 11, 1971 Switzerland 140801/71 US. Cl. 139/25, 139/291 Int. Cl D03d 39/22 Field of Search 139/25, 29, 291,

References Cited UNITED STATES PATENTS Northrop 139/291 [57] ABSTRACT The terry cloth weaving machine is provided with a means to vary the length of cloth travel downstream of the temples so as to maintain the fell straight.

10 Claims, 5 Drawing Figures PATENTEUUEB 18 I975 SHEET 3 [IF 3 METHOD AND APPARATUS FOR WEAVING TERRY CLOTH This invention relates to a method and apparatus for weaving terry cloth.

As is known, during weaving on a weaving machine, the warp yarns and the finished cloth are normally supported under some tension in the weaving plane between a tension beam and a breast beam. Heald shafts form the warp yarns into a shed into which the wefts are picked and in which the wefts are beaten up into the fell by the reed, producing the cloth which is spread to its full width by a temple. The cloth is then deflected at the breast beam and run over a cloth draw-off roller (sand beam) and sometimes further deflecting means before being wound onto a cloth beam. After every blow of the reed, the cloth draw-off roller pulls the cloth forward by a distance corresponding to the gap between two wefts in the finished cloth. This forward pulling motion will herinafter be termed the normal draw-off motion.

Inorder to weave terry cloth, a weaving machine is generally provided with at least one second warp beam, the pile warp beam, off which pile warps are let under less yarn tension than the ground warps or, briefly, without tension. The pile warps are distributed across the entire width covered by the ground warp and are drawn through the shed in accordance with the weaving pattern desired and woven into the cloth as described below.

Relative motion of the front reversing point of the reed and of the fell, occurring in the weaving plane and in the direction of cloth advance, causes the individual weft yarns to be beaten up into the fell either immediately adjacent to the finished cloth (complete blow of the reed) or at a short distance from the finished cloth (partial blow of the reed). This may, for example, be effected in a known manner either by shifting the reed backwards or forwards on a sley in the desired rhythm or by keeping the reed position constant and' moving the warps and cloth, for example, by means of a suitable to-and-fro movement of the tension beam and breast beam, in addition to the normal draw-off motion imparted by the cloth draw-off roller.

Another known solution is to superimpose periodic forward and backward rotations on the normal drawoff motion of the cloth draw-off roller while the warp tension is kept constant by a suitable construction of the tension beam and warp let off device.

A complete blow of the reed is followed by two partial blows in the case of a three-weft binding and by three partial blows in the case of a four-weft binding, whereupon another complete blow follows and the sequence of partial" and complete" blows is repeated as long as terry cloth is being woven. With the first of the 'partial" blows, the picked weft at first stops some distance from the preceding completely beatenup weft, until joined by the next partly beaten-up wefts. The next immediately succeeding complete" blow shifts all the wefts in this sequence which have been partially beaten up forwards along the tauter ground warps so that they adjoin the cloth already formed. The pile warps which are under little or no tension have portions located between the first and subsequent origi-' nally partly beaten-up wefts which are disposed some distance from the shed apex. These pile warp portions are pushed forwards and upwards with the gently beaten-up wefts during the next complete blow to form the desired pile loops.

In known weaving machines in which the complete" and partial blows are produced by shifting the cloth, that is, by shifting the breast and tension beams, the temple may be moved to and fro in the same way as the breast beam. In such a case the temple is movable in a guide running parallel to the selvedge and is coupled to the breast beam or the drive for the breast beam. This prevents unnecessary repeated pulling of the selvedge through the template and consequent damage.

Experience shows, however, that when the temple and breast beam are fully synchronized, the resilience of the cloth and the variable angle of cloth warp round wrap breast beam still cause slight relative motion of the selvedge and temple. Because of the greater friction inside the temple, therefore, the fell recoil is not as large in the vicinity of the temple or selvedges as in the remainder of the cloth not directly gripped by the tem ple. As a result, the shed apex or fell does not run straight across the entire cloth width. The wefts and warps in the vicinity of the temple may therefore be woven more loosely than elsewhere in the cloth, making the pile loops irregular.

Accordingly, it is an object of the invention to insure a uniform fell recoil and regular pile loop formation over the entire cloth width in terry cloth weaving machines.

It is another object of the invention to eliminate relative motion between the cloth selvedge and a reciprocating temple in a terry cloth weaving machine.

Briefly, the invention provides a method and apparatus for maintaining the fell in a terry cloth weaving machine in a straight line across the machine width.

As is known, a usual method of weaving terry cloth having a ground fabric and terry loops woven therein forms a fell from a plurality of supplied ground and pile warps, uses a reed to beat successively supplied wefts into the fell at a front reversing point in a predetermined sequence of partial and complete blows relative to the fell to form the terry loops from the pile warps. In such a method, the resultant cloth is moved from the fell in a predetermined weaving plane and at least one temple is used to grip a selvedge of the cloth to spread the cloth widthwise. In accordance with the invention, such a method also includes the steps of periodically moving the fell forwards and backwards in the direction of cloth advance in the weaving plane relative to the front reversing point, periodically moving the temple forwards and backwards in the direction of cloth advance relative to the front reversing point within a preset amplitude of relative motion; and periodically moving the cloth forward and backwards in the weaving plane within a variable amplitude of motion relative to the front reversing point to adapt the effective amplitude of the cloth motion to the preset amplitude of the temple in order to maintain the fell in a straight line.

With regard to the apparatus of the invention, such provides a terry cloth weaving machine comprising a means for forming a shed of warps having a fell, a reed for beating wefts into the fell at a front reversing point to form a cloth, a means for advancing cloth from the fell int a weaving plane, a means for producing periodic relative motion of the cloth in the weaving plane backwards and forwards in relation to the direction of cloth advance over a preset amplitude, at least one temple which is movably mounted in the direction of cloth advance and is coupled to the means for producing periodic relative motion of the cloth, and means for varying the amplitude of relative motion of the cloth relative to the amplitude of relative motion of the temple. Where the means for producing cloth motion includes a reciprocally mounted breast beam over which the cloth passes and which is coupled to the temple as well as a cloth draw-off roller spaced from the breast beam, the means for varying the cloth motion can take various forms. For example, in one embodiment, the means for varying the amplitude may comprise an additional cloth diverting element which is situated between the temple and the cloth draw-off roller and whose position can be moved at right-angles to the direction of cloth advance.

Alternatively, in another embodiment, the means for varying the amplitude of the change in the distance travelled by the cloth may comprise an additional cloth deflecting element (such as a deflecting rail or a roller) which is situated between the breast beam and the cloth draw-off roller and whose distance in the direction of cloth advance from the front reversing position of the breast beam is smaller (to reduce the amplitude) or greater (to increase the amplitude) than the distance from the rear reversing position of the breast beam.

By means of the invention, the amplitude of the relative motion of that portion of the cloth situated in the weaving plane is adapted to the amplitude selected for the relative motion of the temple in relation to the front reversing point of the reed, that is, is greater or smaller according to the type of machine and material to be woven. Thus, the fell recoil in the ground, that is, in the central portion of the cloth, can be adapted tothe fell recoil in the selvedges, which pass through the temples, so that the shed apex or fell runs straight across the entire weaving width.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates an exaggerated simplified side view of a terry cloth weaving machine according to the invention;

FIG. 2 illustrates a modified means for varying the cloth motion according to the invention;

FIG. 3 illustrates a further modified means for varying the cloth motion according to the invention;

FIG. 4 illustrates a simplified plan view of the cloth end of another weaving machine embodying the invention, having a fixed breast beam, movable temple and cloth moved backwards and forwards by the cloth draw-off roller; and

FIG. 5 diagrammatically illustrates a process of form ing a terry cloth with a three-weft binding.

Referring to FIG. 1, the terry cloth weaving machine is provided with heald shafts l, 2, as is known, which are supplied with

ground warps

3, 3 and pile warps 4, 4 drawn off warp beams (not shown) and distributed across the weaving width. The

heald shafts

1, 2 serve to form a shed 5 from the ground and pile warps through which wefts are picked by a shuttle 6. A reed 7 is also provided to beat up the wefts into the fell, or shed apex 8 at a front reversing position whereat the reed 7 carries out a complete blow. The reed 7 occupies a rear reversing position 7' during picking as indicated in broken lines; The reed 7 is operated so as to carry out a pivoting motion as indicated by the arrow 9 between the two reversing positions.

Temples 16 (only one of which is shown for clarity) are disposed on opposite sides of the machine to grip the selvedge of the cloth 10 which is formed at the fell 8 and to spread the cloth l0 widthwise. A breast beam 11 is mounted downstream of the temples 16 and is reciprocally mounted in a known manner to move between a front reversing position 11' and a rear reversing position as shown in solid line. A take-up means including a cloth draw-off roller 12 (sand beam) and a deflecting roller 14 is mounted below the breast beam 11 so as to deflect the cloth about the breast beam 11 and

rollers

12, 14 before being wound on a cloth beam (not shown). The cloth draw-off roller 12 is driven continuously or intermittently (eg by a ratchet drive) in a known manner as indicated by an arrow 13 and draws the cloth 10 off at its normal draw-off speed, that is, by a distance equal to that desired between two successive wefts in the finished cloth after every blow of the reed 7.

In order to produce complete and partial blows of the reed 7, the breast beam 11, which is in the form of a strip running underneath the cloth 10 across its entire width, is moved in the weaving plane as indicated by a double arrow 15 from the rear reversing or complete blow position 11 shown with solid lines to the front reversing or partial blow'position l 1 in rythmn with the desired complete and partial blows along a guide and via a conventional drive mechanism (not shown). In order to clearly indicate the resulting effect, the amplitude of the breast beam motion is shown not to scale but is highly exaggerated. In reality, the magnitude of this motion is of the order of l to 2 centimeters (cm), depending on the type of cloth, the yarn material and the pile depth desired. By shifting the breast beam 11 forwards into the front position 11, the distance to be travelled by the cloth 10 between the reed reversing point 7 and the cloth draw-off roller 12 is lengthened in a known manner. Since the cloth 10 is gripped by the cloth draw-off roller 12, the fell 8.shifts to the right as shown in FIG. 1, for example to 8'. Since the position and motion of the reed 7 remain the same in this embodiment, the next weft, which is brought to the fell 8 with a partial blow of the reed 7, is not completely beaten up but remains at first at 8, that is, some distance from the previous, completely beaten-up weft which is now at about 8'. The pile warp yarns 4, 4' are bound in and gripped between the first and second and any further partly beaten-up wefts so that, when the breast beam 11 and therefore the fell 8 return to their

complete blow positions

11 and 8, the pile warps 4, 4, being more loosely held than the highly

tensioned ground warps

3, 3' are shifted forwards with the wefts and pushed upwards to form the desired pile loops.

The temples 16 are coupled rigidly to the breast beam 11 in a known manner by guide bars 17, to follow the breast beam motion between 11 and 11' precisely and to take up position 16 during a complete blow .and position 16' (shown with broken lines) during a partial" blow.

In order to reduce the amplitude of the additional cloth motion compared with that of the breast beam 11, a means in the form of a stationary deflecting element 18 is disposed between the breast beam 11 and the draw-off roller 12 perpendicularly of the path of the cloth 10. The distance 19' of this deflecting element 18 from the front breast-beam reversing position 11' is less (19' 19) than the distance from the rear reversing position 11.

In operation, as the breast beam 11 and temples 16 are reciprocated, the distance the cloth has to travel from the fell 8 to the draw-off roller 12 and, particularly, from the breast beam 11 to the draw-off roller 12 varies from a maximum when the breast beam 11 is in the rear reversing position to a minimum when the breast beam is in the front reversing position 11. As a result, during partial blows by the reed 7, the amplitude of the additional cloth motion is reduced relative to that of the breast beam 11 and adapted to the amplitude of the temple motion by means of a suitable choice of the relative position of the deflecting element 18 and the breast beam 11. This prevents any relative motion between the selvedge and temples and allows the fell 8 to remain as straight as possible across the cloth width.

Referring to FIG. 2, if the amplitude of the additional cloth motion is to be increased relative to that of the breast beam 11, as may be necessary with a different type of weaving machine and a different quality of yarn, the amplitude-varying means is in the form of a deflecting element 18' whose distance 20' from the front breast-beam reversing position 11' is greater (20 20) than its distance from the rear reversing position 11.

FIG. 3 shows another variant of the means for guiding the cloth 10 in the zone between the reed reversing point 7 and the cloth draw-off roller 12, for example, between the temple l6 and breast beam 11. In this case, the means includes a diverting element which comprises two fixed rollers 22 and a roller 24 situated between the fixed rollers 22 which is vertically movable as indicated by a double arrow 23. The position of the movable roller 24 is altered perpendicularly to the direction of cloth advance in synchronism with the breast beam or the cloth draw-off motion. If the roller 24 is moved up to 24 while the breast beam is in the front position 11', the amplitude of the cloth motion increases relative to that of the breast beam. If the roller motion 23 during this time is downwards from 24' to 24, the amplitude of the cloth motion decreases.

As a further alternative, the deflecting element 18 as shown in FIGS. 1 and 2 may, for example, be movable in a plane parallel to the weaving plane e.g. between a position under and to the right of the breast beam 11 as shown in FIG. 1 to a position directly under the breast beam 11 as shown in FIG. 2. Such an embodiment, also, permits the amplitude of the adidtional cloth motion to be varied continually. As a still further alternative, the deflecting elements 18, 18' as shown in FIGS. 1 and 2 may be omitted. In this case, in order to provide the desired variation in the amplitude of the cloth motion, the cloth draw-off roller 12 may be situated slightly higher up, that is, closer to the breast beam and may be mounted for reciprocating horizontal movement wherein movement forwards (to the right as shown in FIG. 1) reduces the amplitude of the cloth motion in much the same way as described above while backwards movement (to the left as viewed) increases the amplitude.

Referring to FIG. 4, in a further embodiment, the taut ground warps 3, 3' entering at the top as viewed run through the shed 5 into the reed 7, which has just beaten a weft (not shown) up completely into the fell 8. The temples l6 grip the selvedge areas 10,, of the cloth l0 and spread the cloth to its full width. The cloth 10 then runs down over a breast beam 11 in the form of a stationary but rotatable roller and round the cloth draw-off roller 12, up over the deflecting roller 14 and then onto the cloth beam (not shown). The next weft is then picked into the shed 5 by the shuttle 6 through a position 21 after the reed 7 has pivoted back into the rear position 7'. In this embodiment, the to-and-fro motion of the cloth 10 is produced by making the cloth draw-off roller 12 turn backwards and forwards in a known manner in addition to its normal draw-off motion (indicated by the arrow 13). The position of the temples 16 and selvedge during a partial" blow of the reed 7 is indicated by broken lines at 16'. In this embodiment, the desired variation of the amplitude of the to-and-fro cloth motion can be obtained by means of a diverting element 24 (not shown) according to FIG. 3, located between the temple l6 and the cloth draw-off roller 12.

Referring to FIG. 5, the finished cloth 10 containing a series of pile loops formed from pile warps is shown being drawn off to the right as indicated by an arrow. In each series two pile loops 4 project upwards and two pile loops 4' project downwards from the ground fabric which is formed from the ground warps 3, 3 and the successively picked wefts 21,, (complete blow), 21 (first partly beaten-up weft) and 21,, until the wefts adjoin the cloth 10 already formed. The pile warps 4, 4 under little or no tension, however, are bound in (woven in) by the

wefts

21, and 21 These pile warps 4, 4' are pulled to the right together with these wefts and pushed up to form another row of pile loops, whereupon another series of three wefts (two partly and one completely beaten up) are picked, and so forth.

If the second ground 4' of pile warps is omitted, only the upper pile loops 4 form on the cloth.

What is claimed is: 1. In a method of weaving terry cloth having a ground fabric and terry loops woven therein in a weaving frame wherein a fell is formed from a plurality of supplied ground and pile warps, a reed beats successively supplied wefts into said fell at a front reversing point in a predetermined sequence of partial and complete blows relative to said fell to form said terry loops from said pile warps, cloth is moved from said fell in a predetermined weaving plane, and at least one temple grips a selvedge of the cloth; the steps of periodically moving said fell forwards and backwards in the direction of cloth advance in said weaving plane relative to said front reversing point,

periodically moving said temple forwards and backwards in the direction of cloth advance relative to said front reversing point within a preset amplitude of relative motion; and

periodically moving the cloth forwards and backwards in said weaving plane within a variable amplitude of motion relative to said front reversing point to adapt the effective amplitude of the cloth motion to said preset amplitude of the temple, to maintain said fell in a straight line over the weaving machine width.

2. A terry cloth weaving machine comprising means for forming a shed of warps having a fell;

a reed for beating wefts into said fell at a front reversing point to form a cloth;

means for advancing cloth from said fell in a weaving plane;

means for producing periodic relative motion of the cloth in said weaving plane backwards and forwards in relation to the direction of cloth advance over a preset amplitude;

at least one temple movably mounted in the direction of cloth advance and coupled to said means for producing periodic relative motion of the cloth; and

means for varying the amplitude of relative motion of the cloth relative to the amplitude of relative motion of said temple.

3. A terry cloth weaving machine as set forth in claim 2 wherein said means for producing periodic relative motion of the cloth includes a breast beam coupled to said temple, said breast beam being reciprocally mounted in said weaving plane for passage of the cloth thereover and a cloth drawoff roller spaced from said breast beam to receive the cloth from said breast beam.

4. A terry cloth weaving machine as set forth in claim 3 wherein said means for varying the amplitude of relative motion of the cloth includes a cloth diverting element between said breast beam and said draw-off roller for selectively deflecting the cloth therebetween to vary the length of the cloth therebetween.

5. A terry cloth weaving machine as set forth in claim 4 wherein said breast beam is movable between a front reversing point and a rear reversing point and said element is positioned at a greater distance from said bresat beam front reversing position than said breast beam rear reversing position.

6. A terry cloth weaving machine as set forth in claim 4 wherein said breast beam is movable between a front reversing point and a rear reversing point and said element is positioned at a less distance from said breast beam front reversing position than said breast beam rear reversing position.

7. A terry cloth weaving machine as set forth in claim 3 wherein said means for varying the amplitude of relative motion of the cloth includes a cloth diverting element between said temple and said draw-off roller and means for moving said element perpendicularly to the direction of cloth advance in synchronism with the motion of said breast beam.

8. In a terry cloth weaving machine having a cloth take-up means, a reciprocally mounted breast beam over which cloth passes to said take-up means, at least one reciprocally mounted temple for gripping a selvedge of the cloth passing to said breast beam, and means for synchronizing the movement of said temple with said breast beam; means downstream of said temple relative to the direction of cloth advance for varying the length of travel of the cloth downstream of said temple in dependence on the movement of said breast beam.

9. In a terry cloth weaving machine as set forth in claim 8, said means for varying the length of travel of the cloth being a stationary deflecting element disposed between said breast beam and said take-up means perpendicularly of the cloth to deflect the cloth thereabout during movement of said breast beam from a front reversing point to a rear reversing point.

10. In a terry cloth weaving machine as set forth in cliam 8, said means for varying the length of travel of the cloth including a reciprocally mounted roller between said temple and said breast beam for moving perpendicularly of the cloth to deflect the cloth during advance thereover.

Claims

1. In a method of weaving terry cloth having a ground fabric and terry loops woven therein in a weaving frame wherein a fell is formed from a plurality of supplied ground and pile warps, a reed beats successively supplied wefts into said fell at a front reversing point in a predetermined sequence of partial and complete blows relative to said fell to form said terry loops from said pile warps, cloth is moved from said fell in a predetermined weaving plane, and at least one temple grips a selvedge of the cloth; the steps of periodically moving said fell forwards and backwards in the direction of cloth advance in said weaving plane relative to said front reversing point, periodically moving said temple forwards and backwards in the direction of cloth advance relative to said front reversing point within a preset amplitude of relative motion; and periodically moving the cloth forwards and backwards in said weaving plane within a variable amplitude of motion relative to said front reversing point to adapt the effective amplitude of the cloth motion to said preset amplitude of the temple, to maintain said fell in a straight line over the weaving machine width.

2. A terry cloth weaving machine comprising means for forming a shed of warps having a fell; a reed for beating wefts into said fell at a front reversing point to form a cloth; means for advancing cloth from said fell in a weaving plane; means for producing periodic relative motion of the cloth in said weaving plane backwards and forwards in relation to the direction of cloth advance over a preset amplitude; at least one temple movably mounted in the direction of cloth advance and coupled to said means for producing periodic relative motion of the cloth; and means for varying the amplitude of relative motion of the cloth relative to the amplitude of relative motion of said temple.