US3092150A

US3092150A - Weaving method and loom

Info

Publication number: US3092150A
Application number: US31995A
Authority: US
Inventors: Birmans Josef; Steinert Herbert
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-06-02
Filing date: 1960-05-26
Publication date: 1963-06-04
Anticipated expiration: 1980-06-04

Description

June 4, 1963 J. BIRMANS ETAL 3,092,150

WEAVING METHOD AND LOOM Filed May 26, 1960 8 Sheets-Sheet 1 v 'a: w m

INVENTOPS:

5 5/? moms HER BERT s Tan/191- J1me 1963 J. BIRMANS ETAL 3,09

WEAVING METHOD AND LOOM Filed May 26, 1960 8 Sheets-Sheet 2 F/Ci 2 F/C-i 3 INVENTOPS 1 WJW y "M June 4, 1963 I J. BIRMANS ETAL 3, WEAVING METHOD AND LOOM Filed May 26, 1960 8 Sheets-Sheet 3 June 4, 1963 J; BIRMANS ETAL WEAVING METHOD AND LOOM 8 Sheets-Sheet 4 Filed May 26, 1960 INVENTOES 3'0 SEP 3 m l e-R3597 5 ram?)- 7 w W *W June 4, 1963 J. BIRMANS ETAL 3,092,150

WEAVING METHOD AND LOOM Filed May 26, 1960 8 Sheets-Sheet 5 lmmi=illll iIIlIH 1 Mia-"M70195 3'05 FF 505mm: e /raeer i'MlF/PF June 4, 1963 J. BIRMANS ETAL WEAVING METHOD AND LOOM 8 Sheets-Sheet 7 Filed May 26, 1960 /NVENTOP S June 4, 1963 J. BIRMANS ETAL 3,

WEAVING METHOD AND LQOM Filed May 26, 1960 s Sheets-Sheet a F76 l7 F7616 F767. /9

INVENIUIQ s r United States Patent 3,092,150 WEAVING METHOD AND LOOM Josef Birmaus and Herbert Steinert, Velbert, Rhineland,

Germany, assignors, by mesue assignments, to Raymond Dewas, Amiens, Somme, France Filed May 26, 1960, Ser. No. 31,995 Claims priority, application Germany June 2, 1959 7 Claims. (Cl. 139-122) The invention relates to looms comprising picking members which are provided with yarn grippers to engage the yarns to be introduced into the shed and which pick, as a rule, while the slay is in its backward stroke and which co-operate with a patterning device-adapted to select one or more different weft threads simultaneously and to move the same near the picking member, the weft threads being derived from a number of weft bobbins which are arranged substantially fixedly on the same side of the loom as the picking member but separately therefrom. A distinction is made between shuttleless nipper looms and looms comprising nipper shuttles. The invention relates mainly to a nipper loom in which the picking members take the form of two supply and delivery nippers which are so moved through the shed in opposite directions to one another by flexible strips or rodding that the supply nipper carries the weft as far as the centre of the shed and transfers the weft at the centre of the shed to the delivery nipper.

In known conventional looms comprising freely moving shuttles, the fabric is patterned in the weft, by being given different colours, yarn numbers, yarn substances or the like, mainly by means of complicated transmissions having a relatively high mass movement, chambers being moved perpendicularly or in a circle, and the shuttles which are disposed in the chambers acting as bearers for the weft yarns wound on bobbins. On the other hand, in nipper looms in which the picking members for yarnchanging in the fabric are constrainedly guided, only small mass movements and small forces are required, since the weft yarns are drawn off stationary weft bobbins disposed outside the fabric and are brought near the picking member just by being bent. The loom can therefore operate at a much greater rate than can the known changing looms comprising freely moving shuttles.

In the case of looms in which the picking member is guided positively, it has already been proposed, for the selection and picking of different kinds of weft yarns, that the same be brought near the picking member by h0rizon tally moving weft yarn lancets which are disposed outside the fabric edge and which are controlled by a perforated paper card and by transmission elements, the yarn gripper of the picking member to be supplied by means of a circularly oscillating arm. This known arrangement and method has considerable disadvantages. The mechanism for selecting the weft yarns and preparing the same for the picking member by repeated bending is too complicated and liable to disturbances, more particularly where a large number of different kinds of weft yarn, for instance, eight kinds of weft yarn, have to be dealt with.

The result of repeatedly subjecting the weft threads to considerable bending in a number of planes of movement is that the weft yarn in the picking member is overstressed when drawn off the bobbin rapidly over this very bent path. A frequent result, more particularly in the case of short-staple yarn, is breakage of the weft yarn. Another disadvantage is that it is very easy for more than one particular weft yarn to be accidentally transferred to the picking member, more particularly in the case of hairy weft yarns having projecting fibre ends which assist movement of the yarn. Another disadvantage is that the weft yarn lancet is moved on a single-lift basis during each rotation of the slay drive shaft, with the result that, for instance, if

3,@9Z,150 Patented June 4, 1963 twenty weft yarns of the same kind have to be picked, the weft yarn concerned has to be bent twenty times, so that the stressing of the weft yarn is increased.

Other disadvantages are connected with the method of controlling the horizontally moving weft yarn lancets of this known apparatus by means of the endless paper control cards. The perforated card is explored by fine steel needles, a perforation in the card corresponding to a movement of the associated horizontal lancet and therefore to a preparation of the associated weft yarn for the picking member. The gaps between the card perforations and the needles must therefore be very accurate if errors are to be avoided. Another disadvantage is that only one operating element is provided for each horizontal weft yarn lancet, so that the control perforations in the card must always be disposed lengthwise thereof in the same direction. Due to the necessary considerable gap between perforations, the control card is relatively long, a feature which is very disadvantageous, more particularly in the case of long weft yarn pattern repeats, and very expensive. Another disadvantage is that the control unit shaft must rotate once for each picking period (one rotation of the slay drive shaft), consequently the speed of the loom can be raised only to limited extent if operational reliability is not to be impaired. Finally, the known selecting device is devoid of any safety device for preventing the unwanted picking of a number of weft yarns into the same shed, an error which can be caused by card errors, sticking of the needles or other faults in the mechanism.

The invention has for its object to obviate these difiiculties and disadvantages and provides a reliable loom and a weaving method which is much less harsh on the Weft yarns than the prior art methods and which therefore pro vides a fabric of very good quality.

According to the main features of the method according to the invention, instead of the various kinds of weft yarn being guided rectilinearly in their inoperative position, then subsequently bent repeatedly for picking, at the yarn nipping station where the weft yarns are prepared for the picking member and engaged thereby, the converse is effected, the weft yarns being guided at least substantially rectilinearly in their picking position, while the yarns which it is required not to use are bent into their inoperative position out of the yarn-catching path, from which inoperative position the weft yarns to be picked are returned separately or severally, depending upon the pattern, to the straight position and transferred to the picking member. Consequently, the weft yarn in the picking member is drawn off its bobbin rapidly precisely at the time when the weft yarn is most stressed by the sudden acceleration, in an at least substantially straight line, a feature which greatly reduces yarn stressing and weakening and even complete breakage. It has been found very advantageous if the weft yarns which, when in their operative position extend at least substantially straight from the yarn carrier eyelets to the edge of the fabric, are raised vertically into the inoperative position and then simply allowed to drop or are constrainedly lowered, severally or separately as required, for picking according to the pattern.

In the apparatus according to the invention, the various kinds of weft yarn are guided at least substantially rectilinearly from the yarn carrier eyelets to the fabric edge at the yarn interception station of the loom where the weft yarns are prepared for and engaged by the picking :member, and the loom comprises weft yarn lancets so disposed and controlled as to bend the weft yarns when not in use from the yarn-intercepting path into the inoperative position and as to return the weft yarns, separately or severally as required for the weft pattern, from the inoperative position to the straight position, in order that the weft yarns [may be transferred to the picking member in their straight position and picked by the picking member into the shed with an at least substantially straight draw-off from the said eyelets. Very advantageously, the weft yarn lancets thus controlled are disposed vertically in order that they may raise the weft yarns vertically out of the thread-intercepting path when such yarns are not in use, whereafter the weft yarns drop or are lowered positively into the straight position separately or severally as required by the pattern.

Very advantageously, a conventional shedding device, more particularly a dobby known per se, can be used for this purpose and be appropriately provided with weft yarn lancets and lancet levers.

Conveniently, the movement of the weft yarn lancets is on a double-lift basis and is mainly derived not from the perforations in the control card but from raised parts or cams thereon. A safety device can be provided to prevent accidental double picking into the same shed and to stop weft yarn supply when the direction of drive shaft rotation is reversed.

Other objects and features of the invention will become apparent from the following detailed description of the drawings in which embodiments of the invention are illustrated by way of example with reference to a nipper loom comprising nipper members operating in opposite directions to one another. In the drawings:

FIGURE 1 is a front elevation showing the main features of a loom, a number of separate weft yarn bobbins being disposed on one side of the machine, such bobbins being used alternately as required by the patterning, the position of the device for selecting and supplying the weft yarns also being visible,

FIGURE 2 is a diagrammatic front elevation showing the position of the weft yarns and the arrangement of the weft yarn lancets and of the weft yarn feed device,

FIGURE 3 is a plan view corresponding to FIG- URE 2,

FIGURE 4 is a perspective view showing the relative positions of the selector device and of the weft yarn feed device, some parts being omitted for clarity,

FIGURE 5 is a view in section and to an enlarged scale of the selector device shown in FIGURE 4,

FIGURE 6 is a part of the plan view of FIGURE 5,

FIGURE 7 diagrammatically illustrates the operating principle of the lifting members shown in FIGURE 5 in the normal position,

FIGURE 8 illustrates a piece of a control strip with a few control cams fitted to it,

FIGURE 9 diagrammatically illustrates the operation of the drawhook control for shedding devices having their own control cards,

FIGURE 10 is part of a plan view corresponding to FIGURE 9,

FIGURE 11 is an elevation of the weft yarn feed device as seen in the direction of weft yarn movement,

FIGURE 12 is a front elevation of a detail of the control card mechanism,

FIGURE 13 is a side elevation of the mechanism shown in FIGURE 12,

FIGURE 14 is a perspective view of part of the control card mechanism shown in FIGURES 4, 5 and 8,

FIGURES 15-19 illustrate details of such strip and various kinds of control cams therefor.

In the loom shown in FIGURE 1, weft yarn bobbins 1 are placed in a frame 2 on the left-hand side of the loom as seen from the operators position. Weft yarns 3 run off the bobbins 1 by way of yarn brakes 4 and yarn carriers 5 to an edge 6 of a fabric. If required, the bobbins 1 and the other elements just mentioned can be disposed on the right-hand side of the loom.

Weft yarn lancets 8 having eyelet-like ends through which the weft yarns 3 are drawn are disposed between the yarn carriers 5 and the fabric edge 6 in order to bring the various weft yarns 3 into the region of the yarn gripper of a picking member 7. The lancets 8 are lowered alternately in accordance with the weft yarn pattern required in the fabric, and are controlled by a selector device 9. Disposed at an appropriate distance from the lancets 3 is a weft yarn feed device 10 which moves one or more lowered yarns 3 first horizontally towards the reed and, when the end position of the horizontal movement has been reached, performs a further vertical movement as far as a point where the yarn gripper of the picking member 7 can receive the yarn 3 offered to it. The position of the yarns 3 between the yarn carriers 5 and the fabric edge 6 greatly affects how the yarns 3 are stressed when they are drawn off by the moving picking member 7. The weft yarn arrangement chosen is such that the line which interconnects the yarn carriers 5 and the fabric edge 6 in the picking position is a straight or substantially straight line, so that the yarns 3 are stressed very little.

FIGURE 2 is a view showing the position of the weft yarns 3 as seen from the loom operators position at the front of the loom; the line 3 denotes a weft yarn in its inoperative position, and the chain line 3 denotes a weft yarn ready for picking.

FIGURE 3 is a view looking down on the weft yarns 3, six different weft yarns 3 being shown by way of example in this case. In contrast to the known devices, the weft yarns 3 form a straight or substantially straight line between the yarn carriers 5 and the fabric edge 6, even in this plan view. The lancets 8 are moved vertically at a place along the straight line and are so arranged that the straight lines are not interrupted.

The weft yarn control device is illustrated in FIGURE 4. In this device a drawhook knife drive shaft 12 is driven, for instance, by an auxiliary shaft 11, the shaft 12 revolving once for every two revolutions of the slay drive shaft (two picking periods). The shaft 12 can be driven through the agency of chain wheels and a chain, bevel gearing, spur gearing or equivalent transmission elements. If required, the shaft 12 can be driven by a shaft 13 which drives the weft yarn supply device. Secured to the shaft 12 is a cam disc 14 which operates by way of a lever 15, draw rod 16 and lever 17 to oscillate a drawhook knife shaft 18.

Referring to FIGURE 5, double-armed drawhook knife arms 19 are rigidly secured to, and rotate solidly with, the drawhook knife shaft 18. The arms 19 are further interconnected by drawhook knives 20, 20' which can be of cylindrical or prismatic cross-section. Lancet levers 22, at least two of which must be provided, are secured to a spindle 21, are of double-armed design and carry at one end the lancet 8 and at the other end a rocking lever 23 pivotable around a spindle 24.

As can be seen in FIGURE 6, the rocking levers 23 consist of two riveted or welded plates 23a, 2312 or they can be made in one piece. Drawhooks 25, 25' are pivotably mounted at the left-hand and right-hand end of the lever 23. Each lancet lever 22 is drawn upwards by a spring 26, the end position being indicated by the lever 23 abutting stops 27, 27'. This position is shown diagrammatically in FIGURE 7 and will hereinafter be referred to as the normal position. Each

individual draw hook

25, 25 is drawn by its respective spring 28, 28' against a respective card pin 29, 29', the card pin guides 30, 30' locating by means of heads 31, 31' the initial position of the

respective drawhook

25, 25. The shanks 25", 25' of the drawhooks 25, 25' disposed in the lever 23, are not coplanar but are offset from one another as can be seen in the plan view given in FIGURE 6.

On the basis of the normal position shown in FIGURE 7, in which the

drawhooks

25, 25 are disposed outside the area of movement of the drawhook knives 20, 20', the initial position of the lancet levers 22 would remain unchanged, but for the weft yarn changing required, one or more lancets 8 must be lowered by means of the lancct levers 22 in order to bring one or more weft yarns 3 near the yarn gripper of the picking member 7. To

this end, the drawhooks 25, 25' are pivoted towards the drawhook knives 20, respectively and thus move into the path of the rising

drawhook knife

20 or 20. Due to this rising movement of the drawhook knife 20 or 20', the engaged drawhook or 25' respectively is also raised, either the left-hand or the right-hand arm of the lever 23 serving as pivot and abutting the corresponding abutment 27 or 27'.

The upward movement of the

drawhook

25 or 25" raises the spindle 24 so that the left-hand arm of the lancet lever 22 is pivoted upwards around the spindle 21, while the right-hand arm of the lancet lever 22, and with it the lancet 8, are lowered. If the required sequence of picking is such that the same 'weft yarn 3 appears several times consecutively in the fabric, then, for instance, the drawhook 25 can be engaged with the rising drawhook knife 26 during the first picking period, and the drawhook 25 can be engaged with the drawhook knife 20' during the second picking period. A lift compensation is therefore provided within the lever system by the lever 23. The advantage over the known devices is that the lancet 8 and therefore the one or more weft yarns 3 remain in the final position for a definite number of picking periods, that is for as long as the piece of fabric requires the same kind of Weft yarn. Unnecessary movements and stressing of the weft yarns are therefore avoided so that the yarns 3 are not given severe treatment.

This position of the

drawhooks

25, 25 relatively to the :drawhook knives 20, 2G is shown in FIGURE 5. Since the dralwhook knife shaft 18 is driven by way of the drawhook knife driveshaft 12, two picking periods corresponding to one revolution of the shaft 12, the cam disc 14 (FIGURE 4) is designed so that, in the cadence of the movement, for instance, the drawhook knife 20 rises during one picking period, and the drawhook knife 20 rises during the following picking period. This double-1ift arrangement enables maximum loom speed, so far as weft yarn control is concerned, to be much higher than in the single-lift system.

The drawhooks 25, 25' must be engaged periodically with the corresponding drawhook knives 20, 20' in accordance with the required weft yarn sequence, such a periodic engagement being produced by horizontal movement of card pins 29, 29. The horizontal movement thereof is controlled by a perforated strip 32 comprising interchangeable earns 33. The two drawhooks 25, 25 are connected to the lever 23 which is connected to the lancet lever 22. The same is therefore moved in a direction depending upon which of the drawhooks 25 or 25' is being engaged by the cam 33 with the drawhook knife 20 or 20'. A similar arrangement of the

drawhooks

25, 25, lever 23 and, of course, lancet lever 22 is known in dobbies for changing the cross-weaving of the warp yarns.

Referring to FIGURE 8, the

dnawhooks

25, 25 are controlled by means of a continuously perforated endless strip 32. The reference I refers to the first picking period, and the reference II refers to the second picking period. The brackets indicate that the two rows of perforations belong together and act only on one lancet l ver 22.; For example, the top row of perforations acts by way of the card pin 29 to control the associated dnawhook 25, and the next row of perforations acts by way of the card pin 29' to control the drawhook 25'. Cams 33 are placed in the perforations 34 in accordance with the required weft yarn sequence. Consequently, the gap between the rows I and II can be about as small as the gap in the paper strip of a paper card dobby, so that even with long weft yarn repeats the perforated tape 32 is relatively short. The cams ensure that the card pin 29 or 29' can act directly upon the corresponding

drawhook

25 or 25, since the tension of the spring 28 or 28' is absorbed by the card cylinder 35 by way of the

drawhook

25 or 25 in their effect upon the card pin 29 or 29'. The maximum speed of operation is higher than in the prior art apparatus due to the omission of the intermediate pins, cam discs and other intermediate members required in the known control arrangements. Also, variations between the perforation gaps of the strip 32 and between the gaps of the

pins

29, 29 can be greater without any risk of incorrect control of the drawhook 25 or 25'.

As shown in FIGURE 5, the strip 32 is conveyed over the card cylinder 35 which comprises feed projections 36 and which is rigidly secured to a spindle 37. Spindle 37 is rotatably mounted in two swing arms 38 pivotable around a spindle 39. The bottom part of the swing arms 38 carries a roller 40. The rightand part of the swing arm 38 is pulled down by a spring 41 so that the roller 40 bears against a can disc 43 secured to a rotating shaft 42, which latter runs at the same speed as the shaft '12. The drive can be taken from the shaft 12 by way of a chain and chain wheels, bevel gearing and shaft transmission or equivalent mechanical elements. A wheel 44 is connected to the spindle 3-7. The left-hand part of the arm 38 bears a roller-fitted lever 45 comprising a roller 46 which is drawn by a spring 47 into a tooth space in the wheel 44 and which therefore fixes the exact angular position of the perforations 34, strip 32 and cams 33 relatively to the pins 2 9, 29.

A stepping crank 48 comprising a stepping pin 49 is secured to the shaft 42. When the shaft 42 is rotated, for example in a'clockwise direction, the bottom part of the swing arm 38 is moved to the right, and the top part to the left, through the agency of the cam disc 43 and roller 40, so that the cams 33 are moved out of the range of the

pins

29, 29. As the shaft 42 continues to rotate, the wheel 44- is advanced stepwise by one tooth space through the agency of the crank 48 and pin 49. After the wheel 44 has thus been moved on in a stepwise manner, the spring 4 1, corresponding to the return line of the cam disc 43, pulls the top part of the arm 38, and therefore the card cylinder 35, to the right until a cam 33 on the strip 32 moves the

drawhook

25 or 25 by Way of the pin 29 or 23' so far that such drawhook bears against its respective drawhook knife 20 or 20 (position shown in FIGURE 5). However, if no cam is present in the perforation 34 intended for the

29 or 29", the drawhook 25 or 25' remains in its normal position (FIG- URE 7). The card cylinder 35 is moved on in the manner described once every two picking periods, the stepwise movement corresponding to the angle which corresponds to the gap between the rows I, II, I, and II shown in FIGURES.

The weft yarns 3 to be picked are selected in a periodic repetition in accordance with the arrangement of the cams 33 on the strip 32. If only one weft yarn 3 is to be picked during each picking period, only one lancet 8 must be lowered. To ensure that two or more lancets 8 are not lowered because of card errors or other circumstances, with the result of an accidental double or multiple pick, microswitches 78 are so placed above the lancet levers 22 that a circuit 78a of switch 75 is closed whenever any lancet lever 22 descends. This is true since microswitches 73 are normally kept open by the upward urgence of the corresponding lancet lever 22 for maintaining circuit 78a open and thus deenergized. If the movements are correct and only one lancet lever 22 has been lowered, thus, closing the corresponding rnicroswitch 78, and in turn completing the circuit 78a, the voltage of the closed circuit 78a is too low to energize a relay which operates the loom stop motion (not shown). If two or more lancet levers 22 descend, however, the resultant voltage is sufficient for the relay to operate the stop motion. Also, the feeding of the yarn 3 to the picking member 7 is interrupted. Where it is required to pick more than one weft yarn during one picking period for some fabrics, however, the supply circuit for the microswitches 78 is interrupted by a switch (not shown).

Referring to the example illustrated in FIGURE 9,

in looms comprising shedding devices with their own control card for raising or lowering the warp yarns, the engagement of the

drawhooks

25 or 25 with the drawhook knives or 20 can be initiated by the card of the shedding device, in which case the elements 32-36 and 4349 are emitted. Instead, a prism 50 is secured to the spindle 37 and the cam disc 43 is replaced by a double cam disc 43, the oscillating movement of the spindle 37 being retained. The prism 50 is formed with dovetail or similar grooves 51 (FIGURE 10) in which rods 52 can be moved. The same comprise raised parts 53 and are drawn by springs 54 against a stop 55. In the position shown in FIGURE 9, where the raised part 53 is in its lowest position, the card pins 29, 29' are not moved when the prism 50 pivots to the right, consequently the pins 29, 29' do not act upon the drawhooks 25, However, when a rod 52 is moved upwards against the spring 54 by the shedding device, the same operating by way of a connection 56 and of transmission means (not shown), the raised part 53 also rises, the rising movement being limited by an abutment 57. During the subsequent movement of the prism 50 to the right, the

card pin

29 or 29 engages the corresponding .drawhook 25 or 25 with the corresponding drawhook knife 2% or 29. This arrangement performs the same function as the strip 32 and cams 33. Since the rods 52 are actuated by the shedding machine during every picking period, the double-cam disc 43 is provided for this method of control, with the result that the prism 50 is also moved to the right during each picking period.

As shown in FIGURE 4, the weft yarn control device 9 lowers the one or more selected weft yarns 3 into a predetermined position. A weft yarn supply device 10, shown solely by way of example in FIGURES 4 and 11, is provided to bring the selected weft yarn or yarns 3 into the region of the yarn gripper of the picking member 7. FIGURE 4 illustrates the position of the device 19 relatively to the device 9. The supply device drive shaft 13, which extends parallel with the weft thread 3 included in the fabric, is rotated by way of the auxiliary shaft 11 and rotates once during each picking period. Two

cam discs

58, 59 are secured to the end of the shaft 13, the cam disc 58 being provided for horizontal movement of a fork 60, and the cam disc 59 being provided for vertical movement of the fork 60.

FIGURE 11 illustrates the device 10 as seen in the direction of weft yarn movement. The cam disc 58 raises the right-hand arm of a cranked lever 62, such arm bearing a roller 61, so that an arm 63 which is pivotable on the same spindle as the bent lever 62 is pivoted to the right by a pawl 64. The arm 63 is drawn against a stop 66 by a spring 65. The fork 60 is mounted in the arm 63 for rotation around a spindle 67. The forward part of the fork 60 is given an additional vertical movement by a thrust rod 68. Such vertical movement is derived from the cam disc 59 by means of a double-armed lever 69 comprising a roller 70 at its left-hand end. The lever 62 and the double-armed lever 69 are interconnected by a spring 71 so that the rollers 61, 70 are urged into operative engagement with the

cam disc

58, 59. If required, the

cam disc

58, 59 can be designed for positive movement.

The time sequence of the movements of the fork 60 depends upon how the weft yarns 3 are moved by the device 9. In FIGURE 11, the weft yarns in the inoperative position have the reference 3, while a weft yarn which has been lowered by the device 9 has the reference 3. As soon as the weft yarn 3 has reached the position X1, the fork 60 is moved horizontally to the right in the manner hereinbefore described so that the weft yarn 3' is moved as far as position X2. After such position has been reached, the weft yarn 3' is moved vertically downwards as hereinbefore described as far as point Y, the weft yarn 3' being placed behind a hook 73 on the slay 72 and thus being prepared for the yarn gripper of the picking member 7. Control means 74 can be associated 8 with the hook 73 to check for the presence or absence of yarn 3 (FIGURE 4).

To find lost, missing or broken yarns 3, the direction of rotation of the loom drive shaft must be reversed. To this end, a switch 75 for three control conditions is provided and is illustrated by way of example in FIGURE 4. Button 0 stops the loom, button I is for normal operation and button II" is for reverse. When button II is operated, a circuit for a solenoid 76 is also closed, the solenoid 76 acting by way of a rod 77 to raise the pawl 64 (FIGURE 11). Further movement of the cranked lever 62 therefore has no effect on the arm 63 which therefore remains in its initial position. This prevents the fork 60 from colliding with the picking member 7, since the functions occur at different times when the direction of rotation is reversed. The stopping effect of the checking device 74 can also be used to energise the solenoid 76 to prevent a subsequent and unwanted introduction of one or more weft yarns.

Referring to FIGURES l2 and 13, which are a front elevation and side elevation respectively showing how the card pins 29, 29 cooperate with the control earns 33 of the strip 32 shown in FIGURE 8, relatively large variations can exist without any chance of incorrect operations of the

pins

29, 29, a. feature which improves reliability of operation. The normal position of the

pins

29, 29 is shown in full line, and their end positions are shown in chain line.

FIGURES 14-16, which are a perspective view, a fragmented elevation and a view in cross-section respectively of the strip 32, illustrate a thin strip 32 which is formed over the whole card surface with perforations or perforation rows 34 and which engages around part of the card cylinder 35 having the spindle 37 and which is advanced by means of the feed projections 36. Small control earns 33 are placed in the particular apertures 34 required for the pattern and control the card pins 29, 29' as shown in FIGURE 13. In this case the strip 32 is made not of paper but of a plastic foil which is insensitive to atmospheric humidity, a feature which is very advantageous and which prevents incorrect control operations; such incorrect operation is inevitable with paper cards because of the wear of the paper strips. The plastic foils can be made of acetate or polyamine or polystyrene or polyethylene or the like.

Referring to FIGURES 17 to 19, the control earns 33 can be of various kinds. They can be in cylindrical or polygonal shape and can be made of metal or plastic, for example, synthetic resin textile fabric, polyamine, acetate or polyethylene. The control cam 33a shown in FIGURE 17 is tapped and can therefore be connected to the strip 32 by means of a screw or bolt 80 and washer S1. The control cam 33b shown in FIGURE 18 is formed at the top with a bore with an annular groove, while the bottom part 82 in shape resembles a collar-stud. The bottom part 82 is introduced into the corresponding perforation 34 in the strip 32, whereafter the top part 33b is simply pressed over the bottom part 82 in the manner of a snap fastener. The control cam 33c shown in FIG- URE 19 is hollow and takes the form of a two-piece press stud. The top part 330 is inserted through the required perforation 34 in the strip 32 and then secured by means of the pressed-on bottom part 83. In contrast to the conventional paper cards, which have to be punched out by means of expensive card punchers for one particular pattern and are useless for different patterns, the cams 33a, 33b, 330 can be removed from the strip 32 at any time, so that the same can be used over and over again for different patterns or designs.

What is claimed is:

1. A loom in the form of a gripper loom comprising a slay swinging about pivots for executing forward and backward strokes and for picking different kinds of weft yarns, a number of weft yarn bobbins disposed on the same side of the loom, a picking member to grip the yarns,

a selector device, and a weft yarn supply device, said selector device including weft yarn lancets and lancet selector means, and a patterning device, for selecting and controlling the weft yarns which are to be picked, said yarns being drawn off the weft yarn bobbins through yarn carrier eyelets for introduction into the shed during the backward stroke of the slay and being moved transversely of the warp for such introduction by said selector device and in such movement causing the removal of the Weft yarns from a number of bobbins disposed separately from one another on the same side of the loom, the various kinds of weft yarn extending at least substantially straight from the eyelets to the fabric edge when positioned for use at the yarn catching station, the weft yarn lancets being so disposed and controlled as to bend the weft yarns not in use out of the yarn catching path into inoperative positions and so as to move the weft yarns from the inoperative positions into the yarn catching path straight position for picking in accordance with the patterning device, for the purpose of transfer to the picking member and for the purpose of an at least substantially straight draw off out of the eyelets and introduction into the shed when the lancets are in yarn catching path straight position, said lancets being so disposed that the at least substantially straight line formed by the weft yarn between the fabric edge and the nearest yarn support point is not greatly interrupted by the position of the lancets, said lancet selector means so moving the lancets at least approximately vertically downwardly that the weft yarns are brought into a stand-by position near the picking member when the lancets are in yarn-catching path-straight position, and for transferring the weft yarns, said weft yarn supply device having cam means and a weft yarn supply fork mounted for horizontal and vertical movement, said cam means so controlling said weft yarn supply fork, that said fork, when a lancet moves downwardly, first moves horizontally, then is moved vertically towards said picking member, and, in said such fork movement, offers the weft yarn to the picking members.

2. A loom according to claim '1, characterised in that the selector device including the selector means for each lancet comprises two drawhooks, a rocking lever pivotally connected to said drawhooks, a lancet lever pivotally connected to said rocking lever and bearing the lancet, and said selector means further includes drawhook knives and a cam disc which rotates once every two picking periods and which moves a drawhook knife upwards during the first picking period and downwards during the next picking period.

3. A loom according to claim 2, characterised in that the selector device comprises a perforated strip with fitted cams, such strip controlling the movement of the drawhooks into the engaged position of the drawhook knives.

4. A loom according to claim 2, characterised in that the selector device comprises transmission elements which control the movement, initiated by a shedding device having its own control card provided with card pins, of the drawhooks into the engaged position of the drawhook knives and which operate lengthwise movable rods comprising raised parts, which rods, when in their normal position, do not affect the card pins of the selector device and, in their operative position limited by a stop, operate by way of the card pins to bring the drawhooks into engagement with the drawhook knives.

'5. A loom according to claim 2, characterised in that the selector device comprises a stopping relay, microswitch means which, as the lancet levers start to descend, so affect the stopping relay voltage that, if only one lever descends, said relay remains unactuated, While if more than one lever descends, the stopping relay is operated.

6. A loom according to claim 5, characterised in that it comprises a pawl holding said fork in normally operating position a means operated by the microswitch means and by the motor switch, and actuated upon the simultaneous descent of a number of lancet levers and upon reverse running of the loom driving motor, to move said pawl to fork releasing position.

7. A gripper loom comprising a slay pivotally mounted for executing forward and backward strokes and for picking different kinds of weft yarns, a number of weft yarn bobbins disposed separately from one another on the same side of the loom, a picking member to grip the weft yarn at a yarn picking station adjacent the fabric edge, weft yarn carrier eyelets disposed between said bobbins and said picking station, a selector device including Weft yarn lancets, lancet selector means and patterning means for selecting and controlling the weft yarns to be picked, and a weft yarn feed device including a feeding fork mounted :for both horizontal and vertical movement and cam means for so moving said fork for transferring the selected weft yarns by said fork to the picking member at said yarn picking station, the different kinds of weft yarns extending from said bobbins through said eyelets and in a substantially straight line path from said eyelets to the fabric edge when operatively positioned for use at said picking station and being movable transversely of the warp for introduction into the shed during the backward stroke of the slay, said lancets being controlled by said lancet selector means in accordance with said patterning means for upward movement from straight line operative position in which the corresponding weft yarns extend in said substantially straight line path for a substantially straight line draw off through said eyelets and introduction into the shed to inoperative position in which the corresponding weft yarns not in use are upwardly displaced from said straight line path to inoperative position, said lancets being so disposed when in said operative position that the substantially straight line formed by the weft yarn between the fabric edge and the nearest weft yarn support point is not greatly interrupted by the position of the lancets, and upon downward movement of a lancet from inoperative position to operative posi tion to move a corresponding yarn from inoperative position to operative position in said substantially straight line path, said fork being movable by said cam means first horizontally to engage the weft yarn in said straight line path and then vertically towards said picking member to offer said yarn to said picking member at said picking station.

References Cited in the file of this patent UNITED STATES PATENTS 1,943,012 Gabler Jan. 9, 1934 2,429,394 Clairmont Oct. 21, 1947 FOREIGN PATENTS 1,132,916 France Nov. 12, 1956 396,961 Great Britain Aug. 17, 1933 443,251 Great Britain Feb. 25, 1936

Claims

1. A LOOM IN THE FORM OF A GRIPPER LOOM COMPRISING A SLAY SWINGING ABOUT PIVOTS FOR EXECUTING FORWARD AND BACKWARD STROKES AND FOR PICKING DIFFERENT KINDS OF WEFT YARNS, A NUMBER OF WEFT YARN BOBBINS DISPOSED ON THE SAME SIDE OF THE LOOM, A PICKING MEMBER TO GRIP THE YARNS, A SELECTOR DEVICE, AND A WEFT YARN SUPPLY DEVICE, SAID SELECTOR DEVICE INCLUDING WEFT YARN LANCETS AND LANCET SELECTOR MEANS, AND A PATTERNING DEVICE, FOR SELECTING AND CONTROLLING THE WEFT YARNS WHICH ARE TO BE PICKED, SAID YARNS BEING DRAWN OFF THE WEFT YARN BOBBINS THROUGH YARN CARRIER EYELETS FOR INTRODUCTION INTO THE SHED DURING THE BACKWARD STROKE OF THE SLAY AND BEING MOVED TRANSVERSELY OF THE WARP FOR SUCH INTRODUCTION INTO THE SHED DURING THE AND IN SUCH MOVEMENT CAUSING THE REMOVAL OF THE WEFT YARNS FROM A NUMBER OF BOBBINS DISPOSED SEPARATELY FROM ONE ANOTHER ON THE SAME SIDE OF THE LOOM, THE VARIOUS KINDS OF WEFT YARN EXTENDING AT LEAST SUBSTANTIALLY STRAIGHT FROM THE EYELETS TO THE FABRIC EDGE WHEN POSITIONED FOR USE AT THE YARN CATCHING STATION, THE WEFT YARN LANCETS BEING SO DISPOSED AND CONTROLLED AS TO BEND THE WEFT YARNS NOT IN USE OUT OF THE YARN CATCHING PATH INTO INOPERATIVE POSITIONS AND SO AS TO MOVE THE WEFT YARNS FROM THE INOPERATIVE POSITIONS INTO THE YARN CATCHING PATH STRAIGHT POSITION FOR PICKING IN ACCORDANCE WITH THE PATTERNING DEVICE, FOR THE PURPOSE OF TRANSFER TO THE PICKING MEMBER AND FOR THE PURPOSE OF AN AT LEAST SUBSTANTIALLY STRAIGHT DRAW OFF OUT OF THE EYELETS AND INTRODUCTION INTO THE SHED WHEN THE LANCETS ARE IN YARN CATCHING PATH STRAIGHT POSITION, SAID LANCETS BEING SO DISPOSED THAT THE AT LEAST SUBSTANTIALLY STRAIGHT LINE FORMED BY THE WEFT YARN BETWEEN THE FABRIC EDGE AND THE NEAREST YARN SUPPORT POINT IS NOT GREATLY INTERRUPTED BY THE POSITION OF THE LANCETS, SAID LANCET SELECTOR MEANS SO MOVING THE LANCETS AT LEAST APPROXIMATELY VERTICALLY DOWNWARDLY THAT THE WEFT YARNS ARE BROUGHT INTO A STAND-BY POSITION NEAR THE PICKING MEMBER WHEN THE LANCETS ARE IN YARN-CATCHING PATH-STRAIGHT POSITION, AND FOR TRANSFERRING THE WEFT YARNS, SAID WEFT YARN SUPPLY DEVICE HAVING CAM MEANS AND A WEFT YARN SUPPLY FORK MOUNTED FOR HORIZONTAL AND VERTICAL MOVEMENT, SAID CAM MEANS SO CONTROLLING SAID WEFT YARN SUPPLY FORK, THAT SAID FORK, WHEN A LANCET MOVES DOWNWARDLY, FIRST MOVES HORIZONTALLY, THEN IS MOVED VERTICALLY TOWARDS SAID PICKING MEMBER, AND, IN SAID SUCH FORK MOVEMENT, OFFERS THE WEFT YARN TO THE PICKING MEMBERS.