US3811479A

US3811479A - Selvedge forming apparatus in shuttleless looms

Info

Publication number: US3811479A
Application number: US00261955A
Authority: US
Inventors: A Gardella
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-06-21
Filing date: 1972-06-12
Publication date: 1974-05-21
Anticipated expiration: 1991-05-21
Also published as: NL7208462A; GB1399739A; FR2143492B3; FR2143492A1

Abstract

A method is disclosed for the formation of a selvedge in shuttle-less weaving looms, in which, at every one of its forward and backward runs through the warp shed, the weft inserter inserts a double weft thread, that is a twofold-bent weft thread, thus forming a continuous weft having loops on either side of the cloth which are formed by the weft inserter reversing its transverse motion, wherein the loops formed in the sequentially inserted double weft are engaged with one another, on the side of the fabric lying opposite to the entrance side of the weft inserter, in such a manner as to form at least one loop row or chain. Preferably the loop formed in each double weft thread is threaded through the loop of the preceding double weft thread. A device for performing this method is disclosed, wherein a selvedge-forming needle is arranged on the side of the cloth lying opposite to the entrance side of the weft inserter, and is automatically operable in synchronism with the weft inserter in such a manner as to pick up the loop of every new double weft thread which has been inserted by the weft inserter, and to slip them off the loop of the preceding double weft thread, which has been picked up and slipped on the needle shank at the time of the preceding weft insertion, thus causing the loop of the preceding double weft thread to be slipped through the loop of the preceding double weft thread and thus threading the loop of the new double weft thread onto the needle shank.

Description

United States Patent 191 Gardella [111 3,811,479 [451 May 21, 1974 SELVEDGE FORMING APPARATUS lN SHUTTLELESS LOOMS [76] Inventor: Adriano Gardella, 24B, Via A1 Capo di Santa, Genoa, ltaly [22] Filed: June 12, 1972 [21] Appl. No.: 261,955

[30] Foreign Application Priority Data JuneZl Italy. A/7l [52] US. Cl 139/124 A [51] Int. Cl D03d 47/42 [58] Field of Search 139/122 R, 124 A [56] References Cited 7 UNITED STATES PATENTS 3,136,343 6/1964 Firing 139/124A 3,682,205

8/l9'72 Scott .L l39/l24A Primary Examiner-Henry S. Jaudon Attorney, Agent, or Firm-Larson, Taylor & Hinds [57] 7 ABSTRACT A method is disclosed for the formation of a selvedge initiates-la earin lqwativ, ir l sbletsvrety es of its forward and backward runs through the warp shed, the weft inserter inserts a double weft thread, that is a twofold-bent weft thread, thus forming a continuous weft having loops on either side of the cloth which are formed by the weft inserter reversing its transverse motion, wherein the loops formed in the sequentially inserted double weft are engaged with one another, on the side of the fabric lying opposite to the entrance side of the weft inserter, in such a manner as to form at least one loop rowor chain. Preferably the loop formed in each double weft thread is threaded through the loop of the preceding double weft thread.

A device for performing this method is disclosed, wherein a selvedge-forming needle is arranged on the side of the cloth lying opposite to the entrance side of the weft inserter, and is automatically operable in synchronism with the weft inserter in such a manner as to pick up the loop of every new double weft thread which has been inserted by the weft inserter, and to Y slip them off the loop of the preceding double weft thread, which has been picked up and slipped on the needle shank at the time of the preceding weft insertion, thus causing the loop of the preceding double weft thread to be slipped through the loop of the preceding double weft thread and thus threading the loop of the new double weft thread onto the needle shank.

2 Claims, 10 Drawing Figures PATENTEDHAY 2 1 I974 SHEET '4 [If 6 SELVEDGE FORMING APPARATUS IN SHUTTLELESS LOOMS BACKGROUND OF THE INVENTION The present invention relates to shuttle-less weaving looms having one or more stationary supply bobbins and a weft thread inserting member, the so-called weft inserter (in form of a needle, a steel tape, or the like) which is reciprocated to and fro through the warp shed, from one warp side to the other, so as to insert, at every one of its forward and backward runs, a double weft, that is, a twofold bent weft thread, thus forming a continuous weft having loops formed on either side of the fabric by the reversing of the stroke of the weft inserter.

SUMMARY The invention aims to provide a method and an apparatus for the formation of a stable and uniform selvedge on the side of the fabric lying opposite to the entrance side of the weft inserter, i.e., lying opposite to the weft thread supply and insertion side.

To this end, according to the invention, the loops of the successive double weft threads are engaged with one another on the side of the fabric lying opposite to the entrance side of the weft thread inserter, so as to form at least one row or chain of loops.

Particularly, according to one embodiment of the invention, the loop of each double weft thread is inserted through the loop of the preceding double weft.

This method according to the invention may be carried into effect by any desired means adapted for forming a loop chain. A preferred selvedge-forming device of this type is constituted, according to the invention, by a selvedge-forming needle arranged onthe side of the fabric lying opposite to the entrance side of the weft inserter, and automatically operable in synchronism with the weft inserter itself, in such a manner that the said needle will pick up the loop of every new double weft which has just been inserted by the weft inserter, and will then slip off the loop of the preceding double weft which has been picked up and slipped on the needle at the time of the preceding weft insertion, thus inserting the loop of the new double weft through the loop of the preceding double weft, and thus slipping the loop of the new double weft on to the needle shank.

The said selvedge-forming needle may be constructed and operated in any suitable manner, while it may possibly co-operate with any auxiliary devices assisting in the formation of the loop chain. However, according to one preferred embodiment of the invention, the selvedge-forming needle is preferably constituted by a latch needle arranged between the weaving loom breast beam and the weft inserter path and extending substantially parallel to the warp threads, with its hook turned towards the weft inserter path. The said latch needle is preferably turned in such a manner that its hook and its latch come to be disposed sideways, on the needle side lying opposite to the cloth. In synchronism with the weft inserter, this selvedge-forming needle is given a reciprocating motion by the side of the warp, so as to be driven forwards in the direction of the weft inserter path, and to be retracted therefrom, and is also given a reciprocating lifting up and lowering down motion relative to the cloth plane. The whole being so provided that the said selvedge-forming needle advances in the direction of the weft inserter path up to reach its uplifted position, with its latch being opened and its hook being over a thread portion of every new double weft, at the time the weft inserter has completed its forward run (warp entering run), and is then lowered down and retracted from the weft inserter path, while the weft inserter is travelling on its backward run (warp leaving run). The selvedge-forming needle thus picks up and holds the newly inserted double weft, so that a loop is formed about the needle which loop is kept in the hook of said needle, while the loop which has been formed in the same manner from the preceding double weft and is held on the shank of the selvedge-forming needle is caused to slide onwards (on the needle shank, so as to be finally slipped thereoff). The loop from the preceding double weft, by being slipped off the selvedge-forming needle, closes the latch of said needle and is then slipped on the loop which has been formed in the newly inserted double weft, and is held in the needle hook and covered by the needle latch. Whereupon, the selvedge-forming needle is again advanced in the direction of the weft inserter path, so that the loop formed in the new double weft is slipped on the needle shank, whereby it opens the needle latch. The selvedgeforming needle is again lifted up and driven over a thread portion of the next-coming double weft.

The afore-described movement of theknitting machine needle as provided in the selvedge-fonning apparatus according to the invention may be imparted by driving means constructed in any desired manner.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 diagrammatically shows in plan view a shuttleless weaving loom having a selvedge-forming device according to the invention,

FIG. 2 shows an enlarged scale a detail of FIG. I corresponding to the selvedge-forming device,

FIG. 3 shows in plan view the selvedge-forming device, some parts of which have been omitted,

FIG. 4 is a longitudinal vertical section through the selvedge-forming device, on line IV-IV of FIG. 3,

FIGS. 5 to 10 diagrammatically show the essential components of the selvedgeforming device according to the invention, in a perspective view looking in the direction of arrow V in FIG. 3, and in the various selvedge-forming steps.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, 1 denotes the warp beam and 2 denotes the cloth taking up beam of a shuttle-less weaving loom. The insertion of the weft is accomplished by means of a tubular weft inserting needle 3 which is disposed in a horizontal position transversely to the warp 4. In the region of its rear end, that isof the end opposite to the warp 4, the weft thread-inserting needle 3 is fastened to a needle carriage 5 sliding on a fixed guide 6 which is parallel to the said needle 3 and is arranged on one side of the warp 4. The needle carriage 5 is reciprocated on the slide guide 6 in the directions of the double arrow F and is driven for example by means of a rocking driving arm 7 pivotally attached to the said needle carraige 5. The driving arm 7 is pivoted at 8 on the weaving loom frame and is in turn driven by a crank 10 to which it is connected by means of a link 11. The crank 10 is fixedly mounted on the driving shaft 12 and is suitably counterbalanced. In order to permit the rectilinear motion of the needle carriage 5 on its respective guide 6, the driving arm 7 is caused to slide longitudinally through a supporting member 13 which is rotatably mounted on the fulcrum pivot 8. The whole being so provided that the weft-inserting needle 3 is inserted into the warp shed and is caused to run forward until the fore end of the needle has reached the opposite side of the same warp, whereupon the weft-inserting needle 3 is returned to its starting position, in which it is completely drawn out of the warp, as shown in FIG. 1.

The weft thread 14 is supplied from a supply bobbin 15 arranged in a fixed position sideways of the warp 4, on the same side as the weft thread-inserting needle 3. The weft thread 14 is uncoiled from the said supply bobbin 15, is threaded through the rear end of the weftinserting needle 3, is passed through a bore extending the whole length thereof, is drawn out of the needle fore end, andis inserted into the fabric 16. Between the supply bobbin 15 and the weft thread-inserting needle 3 there is arranged a weft stop motion 17, preferably constructed according to other Patents of the same Patentee, which is operated by the bell-crank lever 18 and the rod 19, whose motion is caused by the arm 7 driving the needle carriage 5. The tail end of the thread wound on the first supply bobbin 15 is tied to the starting end of the thread wound on a subsequent or second supply bobbin 115, so that, any time the first bobbin 15 is run out, the supply of the weft thread 14 is assured without interruption from the second bobbin 115. Meanwhile a new first supply bobbin 15 is fitted in place, and its starting end is tied to the tail end of the second supply bobbin 115, and so on.

In practice, and contrary to what appears from the diagrammatic view in FIG. 1, the supply bobbin or bobbins 15, 115 are arranged, beneath the weftinserting needle 3, with their axes converging towards the axis of the weft stop motion 17. In the diagrammatic view in FIG. 1, the supply bobbins 15, 115 and the weft stop motion 17 are therefore shown, for the sake of an easier illustration, turned from a substantially vertical plane, in which the same actually lie, to a substantially horizontal plane, being parallel to the plane of the warp 4.

The weft-inserting needle 3, by being reciprocated through the warp shed 4 from one side to the opposite side, and back, inserts at each forward stroke (by entering into the warp) and at each backward stroke (by coming out of the warp) a double weft T, that is a twofold-bent weft thread, thus forming a continuous weft having loops formed on either side of the cloth 16 by the needle reversing its motion. In FIG. 2, A denotes the loops which have been formed by the double wefts T on the side of the cloth 16 lying opposite to the entrance side of the weft-inserting needle 3.

On the side of the cloth l6 lying opposite to the entrance side of the weft-inserting needle 3, between the path of this latter and the breast beam 109 of the weaving loom, there is arranged the selvedge-forming device according to the invention, which is very diagrammatically shown in FIGS. 1 and 2, and with more constructional details in FIGS. 3 and 4. Referring to FIGS. 3 and 4, the said selvedge-forming device is constituted by a horizontally disposed support 22 extending parallel to the warp threads 4, and fixedly mounted on the loom breast beam 109 so as to be cantilevered therefrom. To the underside of support 22 a bushing 23 is secured, in which a horizontal rod 24, parallel to the warp threads 4, is mounted so as to be longitudinally slidable. On the end of said rod 24 which is turned towards the clothtaking up beam 2 there is fixedly mounted a sleeve 25 carrying on its underside a vertical pivot to which an arm of a bell-crank lever 26 is pivotally attached (see also FIG. 2). The said bellcrank lever 26 is fulcrumed at 27 on the loom breast beam 109, while its other arm is pivotally attached to a driving rod 28 which, in turn, is operated by any suitable part (not shown) of the weaving loom, so as to swing the bellcrank lever '26 and therefore so as to reciprocate toand-fro the slidable rod 24 in the bushing 23, synchronously with the motion of the weft-inserting needle 3, as will be more fully explained hereinafter.

To the opposite end of rod 24, which is turned towards the path of the weft-inserting needle 3, a selvedge-forming head 20 is secured, which comprises a cross bar 29 carrying on its end parts two co-axial bushings 30, whose horizontal axesare directed transversely to the warp threads 4. In these bushings 30 a pivot 31 is rotatably mounted, and on the end of said pivot which projects towards the cloth 16 a selvedge-forming needle 21 is secured, which is constituted by a knittingmachine needle, having a hook 121 and a swinging latch 221. This selvedge-forming needle extends in the longitudinal direction of the warp threads 4 and projects forward towards the path of the weft-inserting needle 3. Furthermore, the selvedge-forming needle 21 is preferably so turned that its hook 121 and its latch 221 will be positioned sideways, on the side of the needle opposite to the cloth 16, as in FIGS. 2 and 3.

Between the two cushings 30 of theselvedge-forming head 20, a flap or blade 32 extending upwardly and having a vertical slot 33 is fixedly mounted on the pivot 31 which carries the selvedge-forming needle 21 (FIG. 4). In front of said flap 32, that is, on its side turned towards the path of the weft-inserting needle 3, a transverse abutment member 34 is provided, which by means of two small sideways projecting members 35 is secured to the corresponding bushing 30. To said trans verse abutment member 34 a substantially horizontal guide rod 36 is secured, which is arranged parallel to the warp threads 4. This guide rod 36 projects rearwardly, that is, towards the loom breast beam 109 and is passed through the slot 33 in flap 32. About the guide rod 36 is wound a helical pressure spring 37 which bears with one of its ends against a spring-bearing bushing 38, secured to the free end of the rod 36, while with its opposite end it bears against a spring-abutmentbushing 39 which is slidably mounted on rod 36 and'has a diameter greater than the width of the slot 33 in flap 32. This slidable spring-abutment-bushing 39 is thereis particularly apparent fore urged by the spring 37 against the flap 32 so-as to swing forward the flap 32 in anti-clockwise direction, as viewed in FIG. 4, thus causing the said flap to bear upon the transverse abutment member 34, as shown by full lines in FIGS. 3 and 4. However the flap 32 can be rocked backwards, that is, in clockwise direction as viewed in FIG. 4, together with the pivot 31 and the selvedge-forming needle 21, thus causing the springabutment-bushing 39 to slide backwards on rod 36 and loading the spring 37.

Referring to FIG. 4, on an upright part projecting from the upper side of the supporting member 22, a balance lever 40 is provided which extends substantially parallel to the warp threads 4 and is pivotally mounted at 41 on the said projecting upright part of the supporting member 22, so as to swing about said pivot 41 which is disposed transversely to the warp threads 4. On the fore end of said lever 40, that is in the direction of the path of the weft-inserting-needle, a stop tooth 42 is provided which engages the flap 32 in a manner that will be more fully described hereinafter. The opposite or rear end of lever 40, that is the end directed towards the loom breast beam 109, is urged upwardly by a pressure spring 43 and is connected to a tie rod 44, which is freely slidable through a slot in the lever 40 and has a threaded end projecting above said lever 40 and on which a large driving head is formed by screwing thereon screw nuts 144. The rod 44 is downwardlyextended through an opening 45 of the supporting member 22 and'is hinged to one arm of a bell-crank lever 46. This bell-crank lever 46 is fulcrumed at 47 on the loom breast beam 109 while the opposite lever arm is pivotally connected to a driving rod 48. As opposed to what has been shown in FIG. 4 for the sake of clearer illustration, the bell-crank lever 46 in practice lies in a plane at right angles to the plane of the drawing, that is, in a plane transverse to the warp, and swings about a pivot which is substantially parallel to the warp threads 4. The driving rod 48 extends therefore horizontally, transversely to the warp, underneath the cloth 16, up to the opposite side of said cloth, where said rod 48 is pivotally connected by one of its ends to one end of a balance lever 49 fulcrumed at 50 on the loom frame 9, as shown in FIG. 1. This lever 49 extends parallel to the warp threads 4, and its opposite end, that is the end in the direction of the warp beam 1, cooperates with the carriage 5 supporting the weftinserting-needle 3 and with any other part rigid with the said weft-inserting-needle 3, and movable therewith. The upper hooking tooth-carrying lever 40 of the selvedge-forming device is normally maintained by the action of its respective spring 43 and of the stop member constituted by the driving head 144 of link 44, in an angular rest position, in which the stop tooth 42 is lowered down into a catching position, in which it comes into engagement with the edge of the flap 32, as shown by full lines in FIG. 4. Upon completion of the forward stroke of the weft-inserting-needle 3 (by which it enters into the warp), the needle carriage 5 abuts against the end of the control lever 49 associated with said carriage, thus swinging the said lever and therefore causing, through the rod 48 and the bell-crank lever 46, a downward movement of tie rod 44. Therefore, the stop tooth-carrying lever 40 of the selvedge-forming device is shifted through the driving head 144 of said tie rod 44, and against the action of spring 43, into an angular position in which the stop tooth or detent 42 is lifted up into a flap-releasing position, in which it does not interfere with the flap 32, as shown by dot-and-dash lines in FIG. 4. The stop tooth 42 may be lifted up into such a releasing position, also independently of the

driving mechanism

44, 46, 48, 49, since the tooth-carrying lever 40 can be swung against the action of spring 43 by sliding on the tie rod 44, away from the head 144 thereof. On its force end, that is on the end turned towards the path of the weft-inserting-needle 3, the tooth or detent 42 has an inclined edge 142 which cooperates with the rear edge of the top end of the flap 32, in a manner which will be described hereinafter.

On the side of the support 22 which is turned towards the fabric 16, between the fabric 16 and the selvedgeforming needle 21, there is provided an upright weftholding wing or arm 51 extending parallel to the warp threads 4 in a forward direction towards the path of the weft-insening-needle 3, and swingably pivoted on a substantially horizontal pivot 52 extending sideways of the support 22, and transversely to the warp threads 4. The upward swinging of said weft-holding arm is limited by suitable abutment members, not shown. In the region of its fore end pointing in the direction of the path of the weft-inserting-needle 3, and at the lever of the cloth 16, the weft-holding arm 51 has a lower edge 54 which is inclined downwardly in the rearward direction and is provided with a notch 53 as shown in FIG. 4. In FIG. 4 also the slay 56 and the reed 55 of the weaving loom are shown in the position that the same assume by the inserting of the weft thread.

'The operation of the selvedge-forming device will be described hereinafter with reference to FIGS. 5 to 10. Assume the starting position to be the one shown by full lines in FIG. 4, in which the rod 24, and the associated selvedgeforming head 20 together with the needle-carrying pivot 31, the selvedge-forming needle 21, and also the flap 32, are fully withdrawn away from the weft-inserting-needle 3, while the stop tooth or detent 42 is in its lowermost position, in which it comes into engagement with the flap 32. The flap 32 projecting radially from the needle-carrying pivot 31 is in a substantially vertical position and is urged by the spring 37 against the transverse abutment member 34. The selvedge-forming needle 21, which is secured to the pivot 31, lies in a corresponding angular rest position slightly downwardly inclined relative to the plane of the fabric 16. The previously inserted double weft T1 is engaged in the notch 53 cut in the weft-holding arm 51 and forms a loop Al about the selvedge-forming needle 21, as shown in FIGS. 5 to 8. The said loop A1 of the preceding double weft thread T1 is engaged in the hook 121 of the selvedge-forming needle 21, in the same manner as shown in FIG. 9 for the loop A2 formed from the next-coming double weft thread T2.

On inserting a new double weft thread T2, during the forward stroke of the weft-inserting-needle 3 by which it enters into the warp shed, the rod 24, together with the associated selvedge-forming head 20, the needlecarrying pivot 31, and the selvedge-forming needle 21, is shifted forwards in the direction of the path of said weft-inserting-needle 3, that is, towards the left-hand side of FIG. 4, in the direction of arrow F1. Since the previously inserted double weft T1 is engaged in the notch 53 provided in the weft-holding arm 51, and is thus held thereby, its loop A1 is slipped back on the shank of the selvedge-forming needle 21, thus automatically opening the latch 221 as shown in FIG. 10 in connection with the loop A2 of the new double weft thread T2. Therefore, the loop A1 of the preceding double weft thread T1 is substantially shifted into the position as shown in FIG. 5, while the latch 221 of the selvedgeforming needle 21 remains opened. At about one-half of the forward stroke of the selvedge-forming head 20 in the direction of arrow Fl, the flap 32, supported by the needle-carrying pivot 31 abuts with its upper end against the detent 42 so that, while the forward run of the rod 24 and of the associated selvedge-forming head is being continued, the flap 32 is tilted backwards, against the action of spring 37, as shown by full lines in FIG. 5, and by dot-and-dash lines in FIG. 4. The needle-carrying pivot 31 is thus revolved in bushings 30 by an angle corresponding to the said tilting of flap 32 which is integral with said pivot, so that the said pivot moves the selvedge-forming needle 21 from its lowered-down angular rest position to a lifted up angular position, which is also shown in FIG. 5, and by dash lines in FIG. 4. At the end of the forward stroke of the selvedge-forming head 20 (position shown in FIG. and by dash lines in FIG. 4), the flap 32 is maintained by the arm 42 in its rearwardly tilted position, and therefore the selvedge-forming needle 21 is in its uplifted angular position, in which its hook 121 comes to be over the plane of the fabric 16.

In the meantime, the weft-inserting-needle 3 has completed its forward stroke and has reached its end position as shown in FIG. 5, in which the thread portion 1 14 of the new double weft thread T2 at the outside of said weft thread inserting-needle 3, lies under the uplifted selvedge-forming needle 21, between the hook 121 and the latch 221 of same. At this moment, the carriage 5 supporting the weft thread inserting-needle 3 hits and pushes the control lever 49 on to the other side of the loom, whereby it causes the detent 42 to be lifted up into its flap-releasing position, against the action of spring 43 and bythe action of the

transmission

48, 46, 44, and of the detent-carrying lever 40, as shown in FIG. 6 and by dot-and-dash lines in FIG. 4. The flap 32 which is no longer held by the stop tooth or detent 42 is swung forwards by the spring 37 up to the abutment cross piece 34, thus causing said flap to assume again its upright position, as shown in FIG. 6 and by dot-anddash lines in FIG. 4. The needle-carrying pivot 31 is then revolved by a corresponding angle in bushings 30, in such a manner that the selvedge-forming needle 21 is inevitably moved from its uplifted angular position to its lowered-down angular rest position, in which it engages the thread portion 14 of th new double weft thread T2 and comes to bear upon the said thread portion 114 with its needle part being comprised between the hook 121 and the still opened latch 221, as shown in FIG. 6. From this Figure it is also apparent that the thread portion 114 of the new double weft thread T2 which is engaged in the selvedge-forming needle 21 is being slightly inflected downwardly bysaid needle.

Subsequently the rod 24 of the selvedge-forming device is driven backwards, to the right-hand side of FIG.

- 4 in the direction of arrow F2, together with the associated selvedge-forming head supporting the needlecarrying pivot 31, the selvedge-forming needle 21, and also the flap 32, while the weft-inserting-needle 3 is beginning its backward stroke by which it comes out of the warp shed. Therefore, and thanks to the aforementioned downward bend of the external thread portion 114 of the new double weft thread T2, the second thread portion 214 of the said new double weft thread T2, which is being pulled out of the inside of the weft thread inserting-needle 3, is passed on to the selvedgeforming needle 21. In this way, the new double weft T2 is held by the selvedge-forming needle 21, thus forming thereabout a loop A2 which is lodged in the hook 121 of said selvedge-forming needle 21, as shown in FIG. 7.

By the beginning of the return stroke of the weftinserting-needle 3, at the time the carriage 5 supporting said needle is drawn away from the control lever 49, the spring 43 again urges the stop tooth or detent 42 down into its flap-engaging position and again moves into starting position the whole of the

mechanism

40, 44, 46, 48, 40 operating the said detent. Therefore,

during the backward stroke of the rod 24 and the associated selvedge-forming head 20, I the flap 32 abuts against the detent 42 which is in its flap-engaging lowered-down position, but the said flap easily goes therebeyond, since by coming to slide upon the inclined detent for edge 142, it will temporarily lift said detent upwards, thus merely causing the detent-carrying lever 40 to swing against the action of spring 43, in the manner as shown in FIG. 7.

During the return stroke of the weft-inserting-needle 3 and the simultaneous backward stroke (arrow P2) of the selvedge-forming head 20, the loop A1 of the preceding double weft thread T1 is slipped on the shank of the selvedge-forming needle 21 towards the end thereof, since the previously formed double weft-is still engaged in the notch 53 in the weft-holding arm 51 and is held thereby, as shown in FIG. 8. The loop A1 of the preceding double weft thread Tl thus abuts against the opened latch 221 of the selvedge-forming needle 21 and swings it forwards upon the hook 121 into the closure position, thus shutting therein the loop A2 of the new double weft thread T2. Whereupon, the loop A1 of the preceding double weft thread T1 is passed on to the closed latch 221 and is slipped off the selvedgeforrning needle 21, as shown in FIG. 9. Thus, the loop A2 of the new double weft thread T2 is threaded by the selvedge-forming needle 21 through the loop A1 of the preceding double weft thread T1, thus forming a link stitch.

At the time the weft-inserting needle 3 has been completely drawn out of the warp shed, and has reached its starting position as shown in FIG. 1, the slay 56, which up to now has remained substantially stationary in the position as shown in FIG. 4, performs its heat, that is, is driven forwards together with the reed 55, towards the loom breast beam 109 (to the right-hand side in FIG. 4), and backwards again. Therefore, the preceding double weft thread T1 comes to be disengaged, by the action of the reed 55, from the notch 53 in the weftholding arm 51, since it is no longer held. by the selvedge-forming needle 21. Whereas, the new double weft thread T2, by having its loop A2 held in the selvedge-forming needle 21, is pushed by the reed 55 against the inclined fore edge 54 of the weft-holding arm 51, thus causing the said am to be temporarily swung upwards about its fulcrum 52, and thus sliding upon the said inclined edge 54 of said arm, up to be engaged in the bottom notch 53, in the place where the preceding double weft T1 was held, as shown in FIG. 10. Therefore, on inserting the subsequent weft, at the time the rod 24 of the selvedge-forming device is again driven forwards in the direction of arrow F1 togehter with the selvedge-forming head 20, the loop A2 of the double weft thread T2 is slipped backwards on the selvedge-forming needle 21, the weft T2 being held in the groove 53 by the weft-holding arm 51. Therefore, the loop A2'of the already inserted double weft thread T2, which is still held in the hook 121 of the selvedgeforming needle 21, by swinging the latch 221 of said needle into its opened position, as shown in FIG. 10, is slipped on the shank of the needle 21 itself. This cycle is repeated in the manner as afore-described.

In FIGS. 2 and 3, and also in FIGS. 5 to 10, it is apparent that by the selvedge-forming process and device according to the invention the loops A of the sequentially inserted double wefts T come to be engaged with one another, that is, come to be threaded the one into the other, on the side of the cloth l6 lying opposite to the entrance side of the weft-inserting-needle 3, in such a manner as to form a selvedge composed by a loop row or chain.

Of course the invention is not limited to the illustrated and described embodiment, but may be practiced by any other means making the selvedge by the same selvedge-forming method, while the aforedescribed selvedge-forming device may equally well be modified, particularly in construction, without departing from the leading principle as described above and as claimed hereinafter.

I claim:

1. A selvedge-forming device for the formation of a selvedge in a shuttle-less loom, comprising a warp shed, a weft inserter forjinserting a double weft thread, Le, a two fold-bent weft thread, at every one of its forward and backward runs through the warp shed, to thereby form a continuous weft having loops on either side which are formed by the weft inserter reversing the transverse motion thereof, loops formed in the sequentially inserted double weft being engaged with one another, on the side of the fabric lying opposite to the entrance side of the weft inverter, in such a manner as to form at least one loop row or chain, said device further comprising a selvedge-forming needle located on the side of the cloth lying opposite the entrance side of the weft inserter, and means for providing automatic operation of said needle in synchronism with the weft inserter in such a manner as to pick up the loop of every new double weft thread which has been inserted by said weft inserter, and to slip this loop off the loop of the preceding double weft thread which has been picked up and slipped on the needle shank at the time of the preceding weft insertion, thus causing the loop of the new double weft thread to be slipped through the loop of the preceding double weft thread thereby threading the loop of the new double weft thread onto the needle shank, a needle-carrying pivot for fixedly mounting the selvedge-forming needle in a substantially radial position, said needle-carrying pivot being arranged transversely to the warp threads, a selvedge-forming head for rotatably mounting said needle-carrying pivot, said selvedge-forming head being slidably guided by the side of the warp threads and being so reciprocated as to be driven forward, in the direction of the path of movement of the weft inserter, and backwards, synchronously with the movement of the weft inserter itself, means for rotating the needle-carrying pivot in one direction so as to angularly lift up the selvedge-forming needle in correspondence with a terminal fraction of the forward stroke of the selvedge-forming head and to turn the needle-carrying pivot in the opposite direction, so as to angularly lower down the selvedge-forming needle at the end of the forward run of the selvedgeforrning head, an arm formed integral with said needlecarrying pivot, a return spring for maintaining said arm in an angular reset position corresponding to the lowered down position of the selvedge-forming needle, a detent which cooperates with said return spring in such a manner that said arm is retained by the detent during the terminal fraction of the forward run of the selvedge-forming head and is thus angularly shifted against the action of its respective retum spring, whereby the needle-carrying pivot is caused to be correspondingly turned, and the selvedge-forming needlev to be swung into the uplifted position thereof, and means for disengaging the detent from the arm of the needle-carrying pivot any time the selvedge-forming head is in the stroke end-position thereof, thereby causing the said arm to be returned to its angular position by the action of its respective return spring, and thus the selvedge-forming needle to be swung into its lowered down position.

2. A selvedge-forming device is claimed in claim 1 further comprising means for controlling the detent cooperating with the arm on the needle-carrying pivot, said controlling means comprising a mechanism responsive to a member afiixed to the weft inserter for disengaging said detent from said arm when the weft inserter is ending the inlet stroke thereof into said warp shed.

Claims

1. A selvedge-forming device for the formation of a selvedge in a shuttle-less loom, comprising a warp shed, a weft inserter for inserting a double weft thread, i.e., a two fold-bent weft thread, at every one of its forward and backward runs through the warp shed, to thereby form a continuous weft having loops on either side which are formed by the weft inserter reversing the transverse motion thereof, loops formed in the sequentially inserted double weft being engaged with one another, on the side of the fabric lying opposite to the entrance side of the weft inverter, in such a manner as to form at least one loop row or chain, said device further comprising a selvedge-forming needle located on the side of the cloth lying opposite the entrance side of the weft inserter, and means for providing automatic operation of said needle in synchronism with the weft inserter in such a manner as to pick up the loop of every new double weft thread which has been inserted by said weft inserter, and to slip this loop off the loop of the preceding double weft thread which has been picked up and slipped on the needle shank at the time of the preceding weft insertion, thus causing the loop of the new double weft thread to be slipped through the loop of the preceding double weft thrEad thereby threading the loop of the new double weft thread onto the needle shank, a needle-carrying pivot for fixedly mounting the selvedge-forming needle in a substantially radial position, said needle-carrying pivot being arranged transversely to the warp threads, a selvedge-forming head for rotatably mounting said needle-carrying pivot, said selvedgeforming head being slidably guided by the side of the warp threads and being so reciprocated as to be driven forward, in the direction of the path of movement of the weft inserter, and backwards, synchronously with the movement of the weft inserter itself, means for rotating the needle-carrying pivot in one direction so as to angularly lift up the selvedge-forming needle in correspondence with a terminal fraction of the forward stroke of the selvedge-forming head and to turn the needle-carrying pivot in the opposite direction, so as to angularly lower down the selvedge-forming needle at the end of the forward run of the selvedge-forming head, an arm formed integral with said needlecarrying pivot, a return spring for maintaining said arm in an angular reset position corresponding to the lowered down position of the selvedge-forming needle, a detent which cooperates with said return spring in such a manner that said arm is retained by the detent during the terminal fraction of the forward run of the selvedge-forming head and is thus angularly shifted against the action of its respective return spring, whereby the needlecarrying pivot is caused to be correspondingly turned, and the selvedge-forming needle to be swung into the uplifted position thereof, and means for disengaging the detent from the arm of the needle-carrying pivot any time the selvedge-forming head is in the stroke end-position thereof, thereby causing the said arm to be returned to its angular position by the action of its respective return spring, and thus the selvedge-forming needle to be swung into its lowered down position.

2. A selvedge-forming device is claimed in claim 1 further comprising means for controlling the detent cooperating with the arm on the needle-carrying pivot, said controlling means comprising a mechanism responsive to a member affixed to the weft inserter for disengaging said detent from said arm when the weft inserter is ending the inlet stroke thereof into said warp shed.