US3494384A

US3494384A - Looms

Info

Publication number: US3494384A
Application number: US695946A
Authority: US
Inventors: Jean Amengual; Georges Lang
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-01-24
Filing date: 1968-01-05
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10
Also published as: BE708093A; FR1518797A; DE1710209A1; IL29279A; AT286896B; GB1213587A; YU32784B; OA02724A; ES349824A1; YU17468A; NL6800953A

Description

Feb. 10, 1970 'J/AMENGUAL ET L I 3,

LOOMS Filed Jan. 5, 1968 v 4 She ets-Sheet 1 Feb. 10, 1970 J. AMENGUAL ET AL 3,494,384

LOOMS Filed Jan. 5, 1968 4 Sheets-Sheet 2 Feb. 10, 1970 AMENGUAL ET AL 3,494,384

LOOMS Filed Jan. 5, 1968 4 Sheets-Sheet 3 Feb. 10, 1970 J- AMENGUAL ETAL 3,494,384

LOOMS Filed Jan. 5, 1968 4 Sheets-Sheet 4 United States Patent int. 01. D03d 47/00, 45/10 US. Cl. 139-125 6 Claims ABSTRACT OF THE DISCLOSURE A weft control apparatus is provided for a loom of the type having a weft supply reel at each side of the frame and a gripping shuttle passing from side to side through the lay comprising a detector coil which is mounted at the center of the lay and connected to an amplifying circuit. An impulse is generated in the coil at each passage of the gripping shuttle by magnetic plates on the shuttle and operates the cutter mechanism and the brake mechanism for the weft supply reel. Means are also provided for applying tension to be inserted weft at the instant of beat up.

This invention relates to improvements in looms of the type employing a pirnless shuttle or a gripping shuttle.

In looms of this type employing a pirnless shuttle or gripping shuttle, the transverse movements of the shuttle from side to side of the loom lay the weft in the shed from two stationary supply reels. In these known looms the shuttle comprises a gripper and a cutter the release of which is carried out, for example, by means of adjustable pressure boxes. This arrangement contains several disadvantages such as the complicated construction of the shuttle and the fact that the shuttle tends to be diverted by shocks to which it is subjected each time it passes a boss. Further experience has shown that if the weft is cut by a mobile cutter carried by the shuttle the cutting is effected in relatively different places between one weft and the next which gives rise to the appearance of more or less irregular fringes at the edges of the selvedge of the cloth.

The main object of the present invention is to avoid these inconveniences in a loom of the type referred to by providing a gripping shuttle which is not subjected to any shock during picking and which ensures that the operation is carried out smoothly in high speed looms.

The loom according to the invention comprises at least 0 two weft supply reels mounted at the sides of the frame and a pirnless shuttle or gripping shuttle picking transversely of the lay characterized in that the shuttle is provided adjacent each end with an internal lip and at least one plate of a ferro-magnetic material capable of generating, during its passage across a detector coil positioned at the center of the lay, an impulse which is amplified electronically for actuating a cutter arranged vertically between the warp yarns adjacent each selvedge for cutting the weft which the said shuttle has laid in the form of a loop passing over the leading lip of the shuttle and a brake which prevents further withdrawal of weft from the supply reel while the shuttle draws the trailing end of the weft into the shed to form a single pick.

This arrangement allows for automatic re-enery of alternate ends of the weft into the shed to form a solid selvedge. The feed eyelets more with the lay during its oscillatory movement so that each weft is drawn rearwardly at the end of the pick i.e. at the moment of beat up to ensure that the weft is under controlled tension to avoid irregularities or other faults which occur in certain cloths of this type.

3,494,384 Patented Feb. 10, 1970 ice The invention will be described with reference to the accompanying drawings:

FIGS. 1 to 7 are diagrammatic plan views showing the successive phases of an operational cycle of a loom in acocrance with the invention;

FIG. 8 is a side view of the shuttle;

FIG. 9 is a plan of same showing the upper face;

FIG. 10 is a plan of same from below;

FIGS. 11 and 12 are respectively sections on lines XI-XI and XIIXII, FIG. 9;

FIG. 13 is a part side View showing the left hand cutting mechanism ready to cut a weft yarn about to be laid in the already open shed;

FIG. 14 is a similar view showing the cutting mecha nism hidden at the moment of beat up of the lay;

FIG. 15 is a plan view of FIG. 13 showing the arrangement of the cutting mechanism at the moment of cutting the weft yarn;

FIG. 16 is a side view showing a brake for the Weft yarn in the open position;

FIG. 17 is a front elevation;

FIG. 18 corresponds to FIG. 16 after the brake has operated;

FIG. 19 shows the brake about to be re-set on the return stroke of the lay;

FIG. 20 is a diagrammatic circuit diagram showing the arrangement for releasing the brakes and the cutting mechanism by the shuttle;

FIG. 21 is a diagrammatic plan of a modification of the invention in which the shuttle causes the impulse for the release of the cutting mechanism and the brakes by the interception of a beam of light which energises a photo-electric cell mounted on the lay.

The loom according to the invention comprises a frame, not shown, of known construction in which a lay 1, having a plurality of reeds 1 thereon is given an oscillated beat up movement in known manner. The arrangement also includes a picking mechanism, also well known, which projects a shuttle through successive sheds alternatively in opposite directions.

The gripping shuttle 2 according to the invention is characterized in that its upper face is recessed from end to end to provide a longitudinal groove 3 into which are lowered, at the required time,

eyelets

4 and 5 through which the weft passes at either side of the loom. A slot 6 is formed in the upper face of the weft inserter 2 to ex tend laterally of the groove 3. A metal member 7, mounted in the slot 6, is formed at each end with projecting

lips

8 and 9 with the lateral edge 10 of member 7 flush with the corresponding side of the groove 3, Below the lip 9 a cylindrical guide 11 is mounted which operates as a thread guide over which the yarn slides while being retained by the lip 9. A guide 12 is similarly arranged below the lip 8.

To facilitate the engagement of the weft alternatively under one or other of the lips 8 and 9 a lateral recess is provided opposite each of them on the side of the shuttle giving access to the upper face thereof. These recesses are designated 13 for the

lip

8 and 14 for the lip 9.

Two

magnetic metal plates

15 and 16 are provided on the base of the shuttle. In the form shown in FIGS. 8 to 12 the

plates

15 and 16 are mounted in a fixed position on the body of the shuttle 2 flush with the lower surface 17 of the base. Alternatively, means may be provided for varying the distance between the

plates

15, 16. Further these latter may be completely enclosed in the body of the shuttle 2 without being directly visible on the lower face 17 of the base. Finally, the ends of the shuttle may be pointed and terminate in

noses

18 and 19, preferably of metal.

It will be appreciated that the shuttle 2 is a very simple member without any moving parts. It may be in a very flat form so that the time of its passage through the shed corresponds to a much larger angle of rotation of the crank shaft than for known looms.

The successive phases of the operation of the loom for the traverse of the shuttle 2 from right to left, according to the invention, are shown in FIGS. 1 to 7. Near the selvedge of the cloth 21), already woven, are two concealed

cutters

21 and 22, the mounting of which is hereinafter described. These cutters follow the movement of the lay 1 and when in the operative position (FIGS. 3 to 6) are positioned vertically between the warp yarns as shown in FIGS. 13 to 15 for the cutter 21. Each

cutter

21 and 22 is employed for cutting the weft yarn laid by the shuttle 2 and its operation is caused by the passage of one of the

plates

15 or 16 across a detector 23 arranged in a central position on the lay 1. This detector 23 is arranged in an electric circuit which will be more fully described with reference to FIG. 20.

At the right hand side of the loom a weft supply 24 provides the yarn 25 which passes over a brake 26 before passing through the feed eyelet 5.

Similarly on the left hand side of the 100m a weft supply 27 provides the yarn 28 which passes over a brake 29 before passing through the feed eyelet 4. The mounting of the brakes, 26 and 29 is shown in detail in FIGS. 16 to 19 and the brakes are released by the passage of the shuttle 2 across the detector 23.

The electric circuit is designed to operate only the cutter 22 and the brake 26 when the shuttle 2 travels from right to left as shown in FIGS. 1 to 7 and only the cutter 21 and brake 29 when the shuttle 2 travels in the reverse direction as will be described later.

The operation is as follows:

The lay 1' in FIG. 1 is shown in the beat up position, i.e. the reeds 1 are in contact with the fell of the cloth 20. The two

cutters

21 and 22 are inoperative while the feeders 4 and are in the forward non-presenting position. The shuttle 2 is in the box at the right hand side of the loom.

In FIG. 2 the lay 1' has moved to the rear most position for the start of picking and the left hand cutter 21 remains in its inoperative position due to a locking means (not shown) while the right hand cutter 22 has entered the shed. The left hand feeder 4 remains in the forward non-presenting position where it is held by a spring (not shown). The right hand feeder 5 is temporarily held by the lay during its rearward movement, its locking to the lay 1' having been effected during the preceding beat up. The right hand feeder 5 thus presents the weft yarn 25 in front of the lip 8 of the shuttle.

As the shuttle 2 is moved to the left in the direction of the arrow 30 as shown in FIG. 3, the weft yarn 25 is engaged by the lip 8 and the eyelet 5 is engaged in the longitudinal groove 3.

The shuttle 2 passes into the shed (FIG. 4) and draws in the weft 25 in the form of a loop of U shape, the top of which slides over the guide 12 of the lip 8. This brings the trailing end 25a of the yarn 25 which is attached to the fell of the cloth 20 at the right hand side into the shed for engagement by the cutter 22. This latter is open at this time while the brake 26 at the right hand side remains inoperative to allow the yarn 25 to be fully withdrawn from the supply reel 24.

As soon as the shuttle 2 passes the detector 23 the resultant pulse actuates the cutter 22 and applies the brake 26. The trailing end 2511 is cut while the brake 26 is applied to prevent further delivery from the supply reel 24. In following this course the shuttle 2 draws into the shed the loop of weft 25 (FIG. 5) to finally lay a single weft (FIG. 6) when the said shuttle 2 passes the selvedge at the left hand side of the cloth.

The shuttle 2 then enters the left hand shuttle box and the lay 1' again beats up (FIG. 7) and lays the weft 25 which has just been inserted. This beat up by the reeds on the lay 1 is accompanied in its movement by the feeder 5 in the direction of arrow 31 to diagonally move the weft between the brake, which remains engaged, and the feeder 5 (FIG. 7). This results in a slight tension being exerted on the weft 25 in the direction shown by the arrow 32 which straightens the weft 25 throughout its length at the exact moment of beat up. Any formation of faults such as waves or irregularities which might be formed in the cloth if the weft remained slack, if it were left in the form shown in the shed FIG. 6, are avoided.

After this cycle a new cycle re-commences from the lefthand side of the loom while the shuttle 2 travels to the right. The left hand cutter 21 is shown in FIGS. 13 to 15. This cutter comprises a metal plate 33 which lies in a vertical plane when the shed is open (FIGS. 13 to 15). This plate 33 is mounted on a rod 34 which extends parallel with the spindle 41 of the loom. The end of the rod 34 which is arranged outside the left hand selvedge of the cloth 20 is aifixed to a support 35 which is carried on arm shaft 36 arranged parallel to the rod 34. This arm shaft 36 arranged parallel tot he rod 34. This arm shaft 36 rotates freely in a stationary support 37 arranged on the side of the loom in order to retain in position the stationary casing 38 of a temple 39. This latter comprises well known teeth or dents arranged helically to consolidate the edge of the cloth 20. The edge engages on the upper part of the temple 39 below a stationary guide 40. The casing 38 carries the spindle 41 of the temple 39.

The rotary arm 36 is mounted in alignment with the spindle 41 of the temple. The free end of the arm 36 is formed with a lug 42 in which engages one end of a torsion spring 43. The opposite end of the spring is anchored to the stationary support 37. In the example described a helical spring 43 is employed. The unit is so mounted that the twisting couple exercised by the spring 43 about the arm 36 tends to resiliently urge the

unit

33, 34, 35 in the direction of the arrow 44 in FIG. 13 until the support 35 engages against a stop (not shown) which locates the lower part of the plate 33 vertically between the warp yarns 45 which form the shed. In this position the plate 33 is situated between the temple 39 and the lay 1'.

However when the lay beats up by pivoting in the direction of the arrow '46 (FIG. 14) it moves into contact with the support 35 which pivots into a horizontal position about the arm shaft 36 in the direction of the arrow 47. The plate 33 thus pivots above the temple 39 and the cutter 21 is raised (FIG. 14) to allow the lay 1' to beat up. The plate 33 is formed with a curved guide surface 48 (FIG. 13) of V shape in profile, in which a weft 28 is engaged when the shuttle 2 enters the shed when travelling from left to right. A bevelled blade 49 is provided which slides vertically from top to bottom in a rectangular slot 50 formed in the plate 33. Due to the tension on the weft 28 during the first portion of the movement of the shuttle the said yarn 28 rests in contact with the bottom of the guide 48 so that at the moment when the blade 49 is lowered an instantaneous cutting of the yarn 28 will occur.

The control of the blade 49 is effected by a picking band 51 the free end of which engages an aperture in the upper end of the blade 49 whilst its other end is affixed to a leaf spring 52 affixed to the support 35. This spring 52 is preferably of steel and the central portion forms a mobile armature capable of being attracted by an electro magnet 53 carried in any known manner (not shown) by the support 35 and/ or the rod 34.

A projection 54 is provided on the back of the lower part of the oscillating support 35 (FIG. 14) for contact by a movable abutment 55 to retain the cutter 21 in the inoperative position when this is required in the cycle of the loom. The arrangement for moving abutment 55 is not shown since this is not critical to the present inven tion. Furthermore, both cutters could be allowed to move into and out of operative position between the waip yarns in synchronization with the movement of the lay.

The right hand brake 26 is shown in FIGS. 16 to 19 and acts on a weft yarn 25 coming from the right hand supply reel 24.

This brake comprises a stationary shoe 56 of arcuate shape over which passes a metal band 57 such as a steel band. One end of the band 57 is afiixed to a stationary support formed by a stirrup 58. The other end of the brake band 57 is engaged by a crank pin 59 of a crank 60 which is capable of oscillating on a stationary support 61 of the shoe 56. The crank 60 is actuated by a torsion spring 62 which tends continuously to swing in the direction of the arrow 63 (FIG. 18) i.e. in the direction of the plane of the lay 1. When the crank 60 is submitted solely to the action of the spring 62, the brake 26 is applied and the yarn 25 is gripped between the shoe 56 and the band 57.

The lay 1' operates a movable rod 64 which pushes the crank 60 in the reverse direction as shown in FIG. 19 at the moment of beat-up. This releases the brake 26 and an arm 65 on the crank 60 engages behind the end of a bell crank armature 66 which oscillates about a pivot 67. This armature 66 is attracted by an electro magnet 68 when this latter is energized. The armature 66 is then moved in the direction of the arrow 69 (FIG. 18), and clears the end of the arm 65. The crank 60 which was held against the action of the spring 62, is suddenly freed and pivots in the direction of the arrow 63 under the action of the spring and immobilizes the weft yarn 25 as shown in FIG. 18.

As soon as the electro magnet 68 ceases to be energized and the rod 64 holds crank 60 in the position shown in FIG. 19 a spring 70 moves the armature 66 which returns to contact a stationary stop 71 (FIG. 16).

Such a brake is susceptible of responding substantially instantaneously from the set position shown in FIG. 16 while the shuttle 2 draws the weft 25 from the supply reel 24. As the shuttle 2 passes the detector 23 the impulse which is setup causes the energization of the electro magnet 68 which attracts the armature 66 to instantaneously free the arm 65 to apply the brake 26.

The electric circuit is as follows:

As shown in FIG. the central portion of the lay 1 carries the detector 23. This latter is formed as a coil on a bobbin preferably formed with a magnetic core in order to increase the sensitivity of the apparatus. An A.C. current from the mains 72 is fed to the primary winding of a transformer 73 the secondary winding of which is connected in series with the detector coil 23. This circuit is made up of two

branches

74 and 75. The branch 74 contains a rectifier 76 preferably consisting of a silica diode, a first resistance 77, a second resistance 78 and a third resistance 79.

Condensers

80, 81 and 82 are connected across the

branches

74 and 75, respectively, in advance of the resistance 77, between this latter and the resistance 78 and after this latter. The circuit constitutes a filter RC acting as a half wave rectifier to ensure the energization of the detector 23 by a unidirectional current as continuous as possible. The condenser 82 remains charged while a constant current i circulates in the resistance 79 and the coil of the detector 23.

When one of the

metal plates

15 or 16 of the inserter 2 passes the detector 23, the reluctance of the magnetic circuit is modified and results in an instantaneous variation of the current. A transient voltage appears across the terminals of the resistance 79 and the voltage variation is implified by a continuous current amplifier 83 which transmits an output sequel employed to operate a silica thyration 84. The collector and the base of this latter feed into a charging circuit 85 consisting of a transformer 86, a resistance 87 and a rectifier 88, preferably a silica diode. The primary of the transformer 86 is arranged across the two branches of the circuit to discharge periodically into a charging circuit when the thyration 84 is conducting.

The circuit of the units 85 is completed by a reversing switch 90 operated by a rotary cam 91 mounted on a half speed spindle of the loom, and controls the four coils of the electro magnets operating the

brakes

26, 29

and the

cutters

21, 22. For clarity the

same references

26, 29 and 21, 22 are applied to the coils of the electro magnets and to the parts themselves as shown in FIG. 20.

The coils of the brake 29 and the cutter 21 are arranged in series and the condenser 89 discharges itself after the cam 91 has moved the reversing switch onto a terminal 92 and when the thyration 84 has become conducting. Similarly the coils of the brake 26 and the cutter 22 are arranged in series and receive the discharge from the condenser 89 when the moving arm of the reversing switch 90 is on the other terminal 93 and the thyration has become conducting. The reversing switch 90 makes contact alternately with the

terminals

92 and 93 as the shuttle 2 travels in one direction or the other through the shed.

Thus it will be understood that at each impulse generated in the detector 23 one of the two

groups

21 and 29 or 22 and 26 receives the discharge of the condenser 89 which causes instantaneously the application of the appropriate brake and the operation of the corresponding cutter.

It must be understood that the same result by replacing the silica thyration 84 by a gas thyration or a transistor of sufficient power to provide a correct release of the brakes and cutters.

Similarly it is clear that the operation of the required controls for the picking of the loom may be obtained either by two

plates

15 and 16 on the shuttle 2 and a single detector 23 on the lay 1' (as shown in the drawings) or by a single metallic plate on the shuttle 2 and two detector coils spaced apart on the lay 1'. The distance apart of the coils may be adjustable, as well as that of the

plates

15 and 16 as already described. This allows for the independent control of the two selvedges of the cloth 20. Further a detector formed with a single nonmagnetic coil on the lay 1' may be employed, the shuttle 2 then being provided with one or two permanent magnets instead of the

plates

15, 16.

Finally a single metal plate may be provided on the shuttle 2 and a single detector coil in the centre of the lay in which case it is sufficient to introduce by electronic means a time delay in the circuit of the amplifier 83 to release the brake and the cutter with the necessary switching according to the direction in which the inserter is being picked.

The foregoing description is only given by way of example and does not limit the scope of the invention by replacement of the detail parts described by other equivalents. In particular the invention is not avoided by making the shuttle 2 more or less heavy according to the type of loom or the nature of the weft and the width of the loom. Further the

brakes

26 and 29 may be of any type with or without previous tensioning so long as the principle of application is carried out in conjunction with an electro magnetic release. In certain cases it may be an advantage to provide means for braking the weft close to each selvedge.

These means may be effected by the displacement of yarn parallel to the warp yarns and the closure of which takes place in advance of that of the shed.

The

cutters

21 and 22 may be arranged outside the shed at each edge of the cloth 20 in which case the ends of the weft are not turned inwardly to form the selvedge.

Finally the detection of the passage of the shuttle 2 may be carried out by any known electric or electronic means. In particular a system of electronic eyes may be employed such as a lamp and a photo electric cell 101 (FIG. 21) mounted on the lay in place of the detector 23 so that the luminous beam 102 is interrupted by each passage of the shuttle 2.

What we claim is:

1. A weft control apparatus for looms in which weft threads extend from the fell at each selvage edge of the warp to supply reels at each side of the loom frame and a gripping shuttle passing from side to side through the shed on a race on the lay; the improvement comprising a projecting lip at each end of said shuttle for engaging the weft between said fell and said supply and pulling the same through the shed, detecting means mounted on the lay for detecting the passage of said shuttle and providing a corresponding electrical impulse, circuit means including said detector means for amplifying said impulse, cutting means and braking means for the weft mounted at each side of said loom, said cutting means and said braking means being actuatable by said amplified impulse, said cutting means being positioned vertically through the warp yarns in close proximity to each selvedge and operable to cut the weft adjacent the selvage during the passage of said shuttle through the shed, said braking means being operable at the time of cutting to grip the weft to prevent further drawing from the reel and to allow the loop formed by the trailing end of the cut weft to be drawn through the shed, and means for applying tension to the inserted weft during the beat up of the lay.

2. A weft control apparatus as set forth in claim 1 wherein the detecting means for detecting the passage of said shuttle comprises a ferro-magnetic plate mounted on said shuttle and a detector coil mounted at the center of said lay and wherein said circuit means includes an amplifier electrically connected in circuit with said detecting means for amplifying the impulse from said coil, a thyratron and a reversing switch; said cutting means and said braking means each including an electro-rnagnet having a coil in said circuit, said cutting means and said braking means at one side of said loom being energizable simultaneously during movement of said shuttle in one direction and the cutting means and the braking means at the other side of said loom being actuatable simultaneously during movement of said shuttle in the opposite direction.

3. A weft control apparatus as set forth in claim 1 wherein the detecting means for detecting the passage of said shuttle comprises a luminous source to create a beam of light and a photo-electrical cell mounted at the center of said lay, the luminous beam being broken at each passage of said shuttle to generate an electrical impulse which is transmitted to the amplifying circuit means which includes a thyratron and a reversing switch; said cutting means and said braking means each including electro magnets having coils in said circuit means, said cutting means and said braking means at one side of said loom being actuatable simultaneously upon passage of said shuttle in one direction and said cutting means and said braking means at the other side of said lOOrn being actuatable simultaneously upon passage of said shuttle in the opposite direction.

4. A weft control apparatus as set forth in claim 1 wherein said two lips on said shuttle are formed at opposite ends of a metal member, weft guide means disposed under each weft with the lateral edges of said lips being flush with the side of a groove extending longitudinally of said shuttle.

5. A weft control apparatus as set forth in claim 1 wherein said cutting means comprises a metal plate arranged vertically, a movable support on which the metal plate is mounted, a stationary support upon which said movable support is pivoted, a spring resiliently biasing said plate into a position where the lower part thereof passes between the warp yarns whereby said plate receives an impact from the lay at each beat up to pivot the plate from between the warp yarns, a further spring, lay means slidably mounted on said plate and controlled by said further spring, guide notch means in said plate for receiving said weft yarn during movement of said shuttle, electromagnetic means carried by said plate and energised by said circuit means for controlling the movements of said further spring and said blade to out said weft while disposed in said notch means.

6. A weft control apparatus as set forth in claim 1 wherein each braking means comprises a stationary shoe of arcuate shape, a flexible metallic band passing over the shoe, means for pivotally mounting one end of said band on said shoe, a crank pin pivotally mounted on said shoe and secured to the other end of said band, torsion spring means for actuating said crank pin in the direction to clamp the weft yarn between said shoe and said band, an arm integral with said crank pin, a mobile armature normally engaged by said arm to separate said band from said shoe and electro-magnetic means actuated by said detector-amplifier system for moving said mobile armature out of engagement with said arm to allow said spring means to move said band into clamping position on said shoe.

References Cited UNITED STATES PATENTS 2,567,751 9/1951 Wolke 139-341 2,604,124 7/1952 Budzyna et al 139l27 2,806,487 9/1957 Zapf 139302 2,809,672 10/1957 Purdy 139-341 3,386,477 6/1968 Durand 139--122 3,124,166 3/1964 Pfarrwaller 139-126 HENRY S. JAUDON, Primary Examiner US. Cl. X.R.