US1965084A - Loom with stationary weft supplies - Google Patents

Description

fiufly 3, 1934. w. POOL LOOM WITH STATIONARY WEFT SUPPLIES Filed Jan. 8, 1932 WILUAM POOL ,S m m H R W W /A patented July 3, 1934 LOOM -WITH STATIONARY WEFT SUPPLIES William Pool, Spondon, near Derby, England, as-

signor to Celanese Corporation of America, a corporation of Delaware Application January 8, 1932, Serial No. 585,479 in Great Britain February 6, 1931 11 Claims.

I method of drawing weft from the supply which consists in forming a loop of weft at one or both sides of the loom and presenting the weft to a dummy shuttle or other inserting device for insertion into the warps.

According to the invention, the weft loop is formed by trapping devices which are movable so as successively to occupy positions in which weft engaged by one trapping device can be engaged by a travelling member which draws the Weft into loop form for presentation to a dummy shuttle or the like, and the movement of the trapping devices is intermittent so that they move quickly into position for the travelling member to engage the weft, and then move slowly through that 'j part of the cycle during which weft is drawn by the travelling member. In this way, not only is reception of the weft by the travelling member rendered more certain, but the passage of the member between the devices occurs at an earlier j period in the loop-forming cycle than is possible with the trapping devices moving at a uniform rate. Two or more travelling members are preferably provided to draw loops in turn, one moving into weft-engagin position during the forinaiion of a preceding loop. The loop may be of a length sufrlcient for one or two picks, the limbs the loops in the latter case being inserted in turn into separate sheds. The latter method of insertion is the one to which the subsequent description will be chiefly directed.

Since in the insertion of v eft from one or both of the loom a length of loop sunicient for two picks r. ust be formed before a single pick can be inserted from either side of the loom, it follows hat the actual loop-forming operation at either side of the loom will only occupy about half the tin a required for insertion of the four picks repre ented by a complete loop-forming and weft-inserting cycle, unless it can be arranged that a second loop can be in the course of formation before the insertion of the second pick of the previously formed loop. This is effected by the intermittent movement of the trapping devices since the devices can be brought into position for the second loop to be in the course of formation while the second limb of the first loop is being picked, and even practically completed before the first loop has been severed from the weft supply. Thus, after the travelling member is clear of the trapping devices, these move more quickly while the loop is being drawn and while they are approaching a succeeding position in which a further loop of weft is to be formed. The rate at which weft is drawn from the supply is thus considerably reduced.

A further advantage arising from this arrangement is that a shorter length of chain or other flexible member can be used, since the second of the travelling members is required to follow the first member in much closer order, no idle run or length of chain being necessary to provide for the movement of the second trapping device during the time occupied by the insertion of the second pick of the first loop. This advantage is of importance in looms requiring to weave fabrics of large width, since the length of chain run between the trapping devices and the point of re lease of the bight of the loop must in general be equal to, and is usually greater than, the width of the fabric, and any idle run necessary for the travelling members would obviously increase the total length of chain to be used. Yet another advantage is that the trapping devices can be spaced closer together, in View of the larger interval provided for the passage of the travelling member between them.

The intermittent motion of the trapping devices may be provided by any suitable mechanism adapted to give the slow and quick movements of the devices at the required points in the loop forming cycle. One convenient mechanism for this purpose comprises a pair of intermeshing helical gears forming a quick-pitch worm gear in the drive for the trapping devices, which may conveniently be mounted on a rotatable disc or other member, and cam means are provided to give an endwise movement of the worm to reduce the efiective rate of drive in one part of the cycle, and increase it at another point. The cam may be formed as a groove on the boss of the gear, which groove engages a fixed pin. The gear is arranged to be slidable endwise along a key on its supporting shaft. The shaft may also be splined or otherwise formed to allow this endwise movement. Instead of the cam arrangement above described a separate cam driven from any suitable part of the mechanism and connected with the gear in any convenient manner, or any other type of mechanism to give the intermittent motion, such as a Geneva-stop mechanism, may be employed.

One form of weft-loop measuring apparatus according to the invention will now be described in greater detail with reference to the accompanying drawing, but it is to be understood that the following description is given by way of example only and is in no way limitative.

Fig. 1 is a general arrangement of the apparatus according to the invention, showing mechanism for producing the intermittent movement of the trapping devices, for driving the endless loop-forming chain, for tensioning the Weft during insertion, and for cutting the weft loop from the supply;

Figs. 2 and 3 show two views in elevation of the gear for moving the trapping devices; and

Fig. 4 shows the extent of the alternating quick and slow movements of the trapping devices.

Referring to Fig. 1, 5 is an endless chain driven by a sprocket 6 and following a path determined by three further sprockets '7, 8 and 9, the sprocket 8 being capable of determining the limit of the loop drawing movement of the chain and the sprocket 9 serving to tension the chain. Gears 10 driven by the sprocket 8 enable the chain to drive a horizontal shaft 11 which carries a worm gear 12 meshing with a worm wheel 13 on a shaft 14 running parallel to the downward run of the chain 5. Bevel gears 15 enable the shaft 14 to give a disc 16 a rotatory motion in a plane parallel to the downward run of the chain. A pair of trapping devices 17, 18, each comprising a fixed jaw 19 and a movable jaw 20, are carried on the face of the disc 16.

On the side of the disc facing the chain 5 moving jaws 20 are provided with plunger-s 22 passing through the disc and operated by a fixed cam 23 carried by a bracket 24 in which the shaft 14 and the shaft 25 of the disc 16 are journalled. The cam 23 thus causes the trapping devices 17, 18 to be opened alternately as the disc 16 performs its rotary movement.

The worm 12 is slidably mounted on a splined portion 26 of the shaft 11 and is connected by a pin 27 passing through a slot 28 in the shaft 11 to the end of a rod 29 within the hollow bore of the shaft. The rod 29 projects from one end of the shaft and is engaged by a bell-crank lever 30 whose follower 31 engages with a cam 32 keyed to the shaft 11. Thus, as the shaft rotates the cam 32 causes the rod 29 to reciprocate within the shaft 11 to produce a similar reciprocation of the worm 12 lengthwise of the shaft. A spring 33 provides an endwise motion of the worm 12. In this way, though the Worm rotates solidly with the shaft 11 and remains permanently in mesh with the worm wheel 13, the endwise motion of the worm imparts a variable angular velocity to the worm wheel 13, and consequently to the disc 16.

The ratio between the maximum and minimum velocities is determined by the cam 32 whose profile regulates the rate of endwise movement of the worm 12. Conveniently the variable angular velocity of the disc 16 is such that the trapping devices 17, 18 move over the arc a of about 90, shown in Fig. 4 at about three times the speed with which they move over the are D. Likewise the arc c is covered at a rate about three times the rate over the are d, it being understood that one trapping device covers the arcs a and 21 while the other covers the arcs c and d.

As will be seen from Fig. 3, pegs 34 which are carried by the chain 5 pass across the face of the disc 16 in a direction which bisects the arcs a and 0 covered by the rapid movement of the trapping devices. Consequently, the trapping devices are able to perform this part of their rotary motion without interfering with the free passage of the pegs 34 and the distance between the pair of trapping devices 1'7, 18 may be reduced to quite a small amount with consequent reduction in the size and Weight of the rotating parts, there being a space at least equal in width to the distance e while the pegs cross the disc. Further, the short distance between the pair of trapping devices is of advantage in providing certain engagement of the weft by the devices, as will now be described.

Weft 44 is taken from a stationary bobbin (not shown) suitably mounted at the side of the loom and is led through suitable guides to the disc 16 where it is held in one of the trapping devices. In Fig. 4. it is shown as held in the trapping device 1'7, the other device 18 being held open by the cam 32. Rotation of the disc 16 causes the weft extending back from the trapping device 17 to the supply to pass across and into the open jaws of the device 18, thus providing a length of weft between the two devices which can be engaged by the pegs 34 as the pegs are carried along the downward path of the chain 5.

The pegs 34 pass over the face of the disc 16 at about the time the open trapping device 18 has commenced to sweep over the are 1), that is while the trapping devices are commencing their slower movement. There is thus ample time for the pegs to pass over the disc Without danger of catching the trapping devices, even though the distance between the devices does not substantially exceed the width of the two pegs.

It will be seen that the pegs 34 draw out a loop of weft between the devices 1'7, 18, his loop being sufficient to provide two picks of weft for insertion into the warps in the manner described in U. S. application S. No. 484,785 filed 27th September, 1930. The loop drawing movement is substantially completed during the slow movement of the trapping devices. When the device 17 has swept over the are d it is caused by the cam 32 to release its hold on the weft for the insertion of the left-hand limb of the loop into the warps, the finger 36 having in the meantime entered the bight of the weft loop to maintain the weft taut and to hold the second limb of the loop in position for presentation to the dummy shuttle or other inserting device as described in U. S. application S. No. 484,785. This presentation is effected by means of a depresser 37 carried by the sley 38 of the loom.

Prior to release of one end of the weft loop by the trapping device 1'7 the trapping device 18 closes on its limb of the loop. The device 18 then sweeps quickly across the are c to cause the weft to extend again between the two trapping devices in readiness for the next loop forming operation, the cycle proceeding exactly as before with the exception that the devices 17, 18 have interchanged their positions.

The second loop is conveniently formed by a second pair of pegs 34 on the chain 5, these passing across the weft extending between the devices at about the time the device 17 commences to sweep across the are I). The first pair of pegs meanwhile returns along the upper run of the chain 5 in readiness for the formation of yet a further loop.

Double pegs 39 are provided to guide the weft squarely into the open trapping devices, during the rotation of the disc and to maintain the weft in proper relation to the devices after its engagement thereby. Further pegs 40 on the opposite sides of the trapping devices also assist in guiding the weft through the devices.

After formation of a weft loop by the pegs 34 the loop is severed from the supply at about the point 41 for which purpose the cutting means described in U. S. application Ser. No. 580,618 filed Dec. 12, 1931 are particularly suitable. These cutting means may be actuated as described in that specification simultaneously with the finger 36 and conveniently by means of the same cam, since severance of the second limb of the weft loop from the supply should take place at the time the finger is raised to allow the limb to be carried into the shed by the dummy shuttle.

Engagem nt of the weft by the trapping devices 17, 18 occurs just after the devices start on are I), while closure of the devices on the weft after loop-drawing takes place at the end of arc b, i. e. about 45 before bottom centre, release of the first limb of the loop taking place at about the same time from the other trapping device which has then traversed are (1. Cutting of the loops from the supply is efiected when a trapping device is covering or has completed are (3.

Since the lower run of the chain is diverted by the sprocket 6, a guard i2 is provided to cause the weft loop to follow the run of the chain as it is drawn out by the pegs 34.

Release of the loop from the pegs may be effected simply by the turning of the pegs as the chain passes round the sprocke '7, but may, however, be controlled by the means described in U. S. application Ser. No. 580,61. filed Dec. 12, 1931.

Since weft loop drawing is an intermittent operation, compensating means may be provided to enable the weft to be drawn from th supply 35 at a steady rate. For this purpose the compensating means described in U. S. application Ser. No. 580,618 filed Dec. 12, 1931 may be employed, these means being conveniently driven in synchronism with the loop-forming mechanism by means of a cam 43 keyed to the shaft 11.

The weft-presenting mechanism shown in Figs. 2 and 3 is conveniently built as a unit which is capable of adjustment in a direction parallel to the shaft 14 to afford a means of regulating the length of the loop in accordance with the width of the fabric being woven. The length of the chain 5 has, of course, to be altered to suit the position of the disc-driving unit. The cutting position of the knife 41 is also adjustable, for the purpose described in U. S. application Ser. No. 580,616. Likewise the position of the sprocket '7 may be regulated to vary the point of release of the loop from the pegs 34.

For insertion of hairpins cf weft from the two sides of the loom, similar loop-forming mechanisms are provided on the two sides of the loom to operate as described in U. 5. application S. No. 434,785 and U. S. application Ser. No. 580,616. The mechanism on the two sides of the loom (where insertion takes place from both sides) may be independently driven by their respective chains; they may, however, be provided with a connecting shaft so that one mechanism drives the other, using only a single chain drive. In this case it may be necessary to provide a universal joint or coupling in establishing the common drive so that any adjustment made in the position of the mechanisms due to peculiarities of loom construction or those required for loop formation may be provided for. Instead of driving the mechanisms through one of the chains, the two mechanisms may be driven by gearing connected to a common drive shaft.

The weft loops of double pick length form f hairpins of weft in the fabric, the bight of each hairpin lying at the side of the fabric from which it was introduced, (thus forming a selvedge), and the ends of the limbs of the hairpin extending to or towards the other edge of the fabric. Ends projecting from the edge of the fabric may be cut off neatly during weaving, or afterwards by means of a cropping machine.

What I claim and desire to secure by Letters Patent iSf- 1. Weft-withdrawing means for looms in which the weft supply does not pass through the warp shed, said means comprising a pair of movable trapping devices, a travelling member adapted to engage weft trapped in one device and extended between said trapping devices and to draw said Weft into loop form preparatory to the insertion of weft from said loop into the warp shed, means adapted to move said trapping devices quickly into weft engaging position just prior to the engagement of the weft by the travelling member, and slowly during loop formation, and means adapted to release the loop from the trapping devices for insertion of weft into the warp shed.

2. Weft-withdrawing means for looms in which the weft supply does not pass through the warp shed, said means comprising a pair of movable trapping devices, a plurality of travelling members adapted to engage in turn weft trapped in one device and extending between said trapping devices and to draw said weft into successive loops preparatory to the insertion of weft from said loops into the Warp shed, means adapted to move said trapping devices quickly into weft-engaging position just prior to the engagement of the weft by each travelling member, and slowly during loop formation, and means adapted to release the loops from the trapping devices for insertion of weft into the warp shed.

3. Weft-withdrawing means for looms in which the weft-supply does not pass through the warpshed, said means comprising a pair of trapping devices, a travelling member adapted to engage a length of weft connected to the supply and extending between said trapping devices and to draw said length into a loop between said devices preparatory to the insertion of weft from said loop into the warp-shed, means adapted to move said trapping devices so that they interchange their positions in successive loop-forming oper ations in such a manner that one device moves into the position previously occupied by the other by two stages of movement, one quick and the other slow, and means adapted to release the loop from the trapping devices for insertion of weft into the warp-shed.

4. Weft-withdrawing means for looms in which the weft-supply does not pass through the warpshed, said means comprising a pair of trapping devices, a travelling member adapted to engage a length of weft connected to the supply and extending between said trapping devices and to draw said length into a loop between said devices preparatory to the insertion of weft from said loop into the warp-shed, a worm gear adapted to impart movement to said trapping devices, means adapted to impart an endwise to and fro movement to said worm in such a manner as to cause the trapping devices to interchange their positions in successive loop-forming operations so that one device moves into the position previously occupied by the other by two stages of movement, one quick and the other slow, and means adapted to release the loop from the trapping devices for insertion of weft into the warpshed.

5. Weft-withdrawing means for looms in which the weft-supply does not pass through the warpshed, said means comprising a rotatable disc, a pair of weft-trapping devices on said disc, at least one travelling member adapted to engage weft extending between said trapping devices and to draw said weft into loop form preparatory to the insertion of weft from said loop into the warpshed, a worm gear adapted to drive said disc comprising a rotatable hollow shaft, a worm slidably keyed upon said hollow shaft, a cam mounted upon said shaft, spring-loaded intermediate means between said cam and said worm adapted to impart a to and fro endwise movement to said worm so as to vary the effective rate of drive of the gear, so that the trapping devices on said disc interchange their positions in successive loopforming operations in such a manner that one device moves into the position previously occupied by the other by two stages of movement, one quick and the other slow, and means to release the loop from the trapping devices for insertion of weft into the warp-shed.

6. A loom in which the weft-supply package ;does not pass through the warp shed, said loom form preparatory to the insertion of weft from said loop into the warp shed, means adapted to move said trapping devices quickly into weftengaging position just prior to the engagement of the weft by the travelling member, and slowly ;during loop formation, and means adapted to release the loop from the trapping devices for insertion of weft into the warp shed.

'7. A loom in which the weft-supply package does not pass through the warp shed, said loom comprising a pair of movable trapping devices, a

travelling member adapted to engage weft trapped in one device and extending between said trapping devices and to draw said weft into a loop sufficient for two picks preparatory to the v insertion of weft from said loop into the warp shed, means adapted to move said trapping devices quickly into weft-engaging position just prior to the engagement of the weft by the travelling member, and slowly during loop formation,

and means adapted to release the loops from the trapping devices for insertion of weft into the warp shed.

8. A loom in which the weft-supply package does not pass through the warp shed, said loom comprising a pair of movable trapping devices, at least one travelling member adapted to engage weft trapped in one device and extending between said trapping device and to draw said Weft into loop form preparatory to the insertion of weft from said loop into the warp shed, means adapted to move said trapping devices quickly into weftengaging position just prior to engagement of the weft by the travelling member, and slowly during loop formation, means adapted to release the loop from the trapping devices, means adapted to in- 'sert picks from said loop into the warp shed, and means adapted to present said picks to said inserting means.

9. A loom in which the weft supply package does not pass through the warp-shed, said loom comprising a pair of trapping devices, a travelling member adapted to engage a length of weft connected to the supply and extending between said trapping device and to draw said length into a loop between said trapping devices preparatory to insertion of weft from said loop into the warp-shed, means adapted to move said trapping devices so that they interchange their positions in successive loop-forming operations in such a manner that one device moves into the position previously occupied by the other by two stages of movement, one quick and the other slow, means adapted to release the loop from the trapping devices, means adapted to insert picks from said loop into the warp-shed, and means adapted to present said picks to said inserting means.

10. A loom in which the weft supply package does not pass through the warp-shed, said loom comprising a pair of trapping devices, a travelling member adapted to engage a length of weft connected to the supply and extending between said trapping devices and to draw said length into a loop between said trapping devices preparatory to insertion of weft from said loop into the warp-shed, a worm gear adapted to impart movement to said trapping devices, means adapted to impart an endwise to and fro movement to said worm so as to cause said trapping devices to interchange their positions in successive loop-forming operations in such a manner that one device moves into the position previously occupied by the other by two stages of movement, one quick and the other slow, means adapted to release the loop from the trapping devices, means adapted to insert picks from said loops into the warp-shed, and means adapted to present said picks to said inserting means.

11. A loom in which the weft supply package does not pass through the warp-shed, said loom comprising a rotatable disc, a pair of weft-trapping devices on said disc, at least one travelling member adapted to engage weft extending between said trapping devices and to draw said weft into loop form preparatory to the insertion of weft from said loop into the warp-shed, a worm gear adapted to drive said disc comprising a rotatable hollow shaft, a worm slidably keyed upon said hollow shaft, a cam mounted upon said shaft, spring-loaded intermediate means between said cam and said worm adapted to impart a to and fro endwise movement to said worm so as to vary the effective rate of drive of the gear, so that the trapping devices on said disc interchange their positions in successive loop-forming operations in such a manner that one device moves into the position previously occupied by the other by two stages of movement, one quick and the other slow, means adapted to release the loop from the trapping devices, means adapted to insert picks from said loop into the warp-shed, and means adapted to present said picks to said inserting means.

WILLIAM POOL.

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