GB2347687A - Yarn carrier for a gripper axminster carpet loom has two sets of locating notches - Google Patents

Abstract

A yarn carrier 10 for a gripper Axminster carpet loom is elongate and axially displaceable to allow a chosen yarn to be presented to an associated gripper 22. The yarn carrier, which is preferably horizontally oriented, has two sets of notches (26, figure 1) and 28 and associated setting bars 48 and 50 which operate independently to engage the notches and arrest the carrier in a predetermined position. The set of notches 28 is used for setting the carrier for the yarn draw-off operation whilst the set of notches (26, figure 1) is used for setting the carrier during yarn cutting. The carrier is displaced by way of an engagement device controlled by a Jacquard, or similar system, and a selector 12 which is pivotally connected 14 to the carrier.

Description

AXMINSTER YARN SELECTION This invention relates to the selection of yarn in gripper Axminster carpet looms and in particular relates to a horizontal selector system.

In gripper Axminster carpet looms typically each gripper has associated therewith a respective elongate bar-like yarn carrier having a plurality of apertures through each of which extends a respective yarn from a supply, these yarns being, for instance, of different colours so that longitudinal displacement of a carrier enables the yarn selectively to be offered to the gripper for a length to be drawn off, severed from the supply, and brought into position to be incorporated into the carpet being woven to produce the desired pattern therein. Control of the yarn carriers is normally achieved by the use of Jacquard or other patterning mechanisms which determine the carrier movement.

Hitherto, the selector system for such looms is mounted at an angle to the horizontal, see for example our GB patent number 2189515. This configuration allows gravity to assist the return of the yarn carriers. While there has been a proposal for a horizontal selector system, in this the yarn carriers are spring loaded for return to the de-selection position. It has been found in practice that the use of spring loaded carriers slows down production since there is a certain amount of oscillation in the carriers and they cannot be accurately positioned if the machine is operated too fast.

The invention seeks to provide a horizontal colour selector system for a gripper Axminster type loom improved in the above respects.

According to the present invention there is provided a gripper Axminster carpet loom in which each gripper has associated therewith a respective elongate yarn carrier having means for locating a plurality of yarns at intervals along its length, each carrier being axially displace able to present a chosen yarn to an associated gripper according to the longitudinal position of the carrier, means for the axial movement ofthe carrier comprising an engagement device movable under the control of the Jacquard or other patterning system and an associated entrainment device comprising an elongate member extending generally in the axial direction of its associated carrier and pivoted thereto, characterised in that the carrier is provided with two sets of notches corresponding to the number and pitch of yarns in a yarn platform, and a setting bar is provided for each set of notches, each setting bar being operatable to engage with a respective notch and arrest the motion of the carrier in a predetermined position.

In addition to the two sets of notches equalling the number of yarns supplied in each yarn platform, there is preferably provided an extra notch set at a defined distance greater than the yarn carrier pitch towards the pivot. The set of notches furthest from the pivot are for setting the carrier for the cutting of the yarn, the set of notches closer to the pivot are for setting the carrier for gripper operation and the extra notch is for setting the carrier at the fully de-selected position, as will be described more fully hereinafter. The provision of the selector bars allows the yarn carrier to be halted completely in an accurately preset position. Thus the loom incorporating the selector system of the invention can be operated much faster than models hitherto available.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which, Figure 1 is a diagrammatic elevational view of a yarn carrier in accordance with the invention; Figure 2 is a similar view to Figure 1 illustrating the gripper and the engagement device at the selection position; Figure 3 is a similar view to Figure 2 at the knife-cut position; and Figure 4 is a similar view to Figure 2 at the fully de-selected position.

Referring to the drawings, a yarn carrier generally designed 10 which comprises an engagement device in the form of a selector 12 pivotally attached at 14 to a setting body 16 of the carrier 10. The setting body 16 includes yarn platforms 18 having, in the present case, twelve aperture means 20 to present a chosen yarn to an associated gripper 22. The setting body 16 terminates in a stabiliser 24 and carries two sets of notches in the form of"V"shaped cut-outs 26,28 as well as a further single"V"-shaped notch 30 closer towards the pivot 14.

As can be seen from Figure 2, each yarn carrier 10 runs between the teeth of two or more combs 32,34 in order to stabilise its lateral position when reciprocating in operation of the loom.

The distal end of the selector 12 is provided with a neb 36, a nick 38, a ramp 40 and a flat land 42. The neb 36 cooperates with one of twelve teeth or slots 44 in an engagement device in the form of a slotted bar 46, each tooth 44 corresponding to a yarn platform.

Two setting bars are provided above the notches in the setting body 16. A carrier setting bar 48 is above the notches 26 and a gripper setting bar 50 is above the notches 28.

Thus the yarn carrier 10 comprises four main components: the stabiliser 24, yarn platforms 18, and setting body 16, which are rigidly attached to one another, and the selector 12 attached to the setting body by means of a pivot pin 14.

Operation of the mechanism is as follows. The slotted bar 46 reciprocates under the control of the loom. The position shown in Figure 2, indicated as'Y'fully positive, is the selection position at which the gripper 22 grips a selected yarn from the yarn platform, in the case shown yarn number 11. The carrier is moved by the relevant tooth 44 of the slotted bar 46 engaging in the neb 36 of the selector. Just towards the end of this selection movement, the gripper setting bar 50 is moved downwards towards the setting body where it locates in the corresponding notch 28 of the gripper carrier setting notches. This both halts the carrier and positions it accurately so that the gripper 22 accurately picks the correct yarn from the relevant yarn platform.

As the motion continues, the gripper carrier bar 50 retracts allowing the carrier to move towards the left (as viewed in Figure 3) at the same time as which the gripper 22 rotates away from the setting body 16 pulling the yarn with it. This movement is known as"draw-off'. At this point a knife (not shown) is moved to sever the yarn from the platform prior to the gripper moving to take the cut-off tuft to be woven into the carpet fabric. In accordance with the invention, the knife cut setting bar 48 at this point engages with a corresponding notch 26 of the knife cut setting notches again stopping and stabilising the bar and preventing it being disturbed by the knife cutting apparatus.

Figure 4 illustrates the final position in which the carrier 10 is in its fully de-selected position.

From Figure 3, the knife cut setting bar 48 is lifted again allowing the bar to move further to the left as shown in the figure after which the gripper setting bar 50 locates with the single notch 30. In this point the yarn carrier 10 is in the maximum rightward position, or"Y" negative position, which is the de-selected position in the loom. The gripper 22 presents the tuft to be woven into the carpet as is known in the art.

A typical loom/Jacquard cycle would take the following form, started from the fully de-selected position shown in Figure : The slotted bar 46 starts its selection movement and the selector 12 is flicked upwardly off the nick 38 by the ramp 40 rising up a location bar 52 until the flat land 42 rests on it so that the neb 36 can be drawn up to engage with a relevant tooth 44 of the slotted bar 46. Which tooth 44 the neb engages with depends on which yarn platform is to be presented to the gripper, there being the same number of teeth 44 as there are yarn platforms and these being spaced according to the pitch of the yarn platforms. The Jacquard mechanism controls the positioning of the slotted bar 46 and thus which tooth 44 is above the neb 36. The gripper setting bar 50 drops down into the corresponding notch of the gripper carrier setting notches 28 to deaden the motion of the yam carrier 10 and align it for the gripper 22. The gripper 22 closes on the selected yarn and the gripper setting bar 50 lifts out of the corresponding notch of the setting body.

As the gripper 22 draws away from the yarn carrier 10, the carrier is moved by the slotted bar 46 to create a near square yarn draw-off. Just before the end of the draw-off, the knife cut setting bar 48 is driven down into the relevant notch 26 of the setting body. This prevents the yarn carrier 10 from being moved by the yarn cutting device (not shown) moving into position and performing the cutting of the yarn. After the yarn has been cut, the knife cut setting bar 48 is lifted out of the setting body and the yarn carrier 10 is driven back to its fully de-selected position (as shown in Figure 4) by the slotted bar 46. Just towards the end of de-selection, the gripper setting bar 50 is driven downwardly into the setting body again, into the nick 30, to align the yarn platforms, ensure the selector 12 is brought down so that its nick 38 locates on the location bar 52 and to deaden the inertia of the yarn carrier. The gripper setting bar 50 is then lifted ready for the next cycle.

If a yarn carrier has not been selected, be it a failure in the selector drive or otherwise, the motion of the loom will not be jeopardised as the gripper 22 will still be able to enter the yarn carrier, though no yarn will be presented, and the carrier setting bars will enter the respective nicks as described above.

The invention provides a simple and accurate mechanism for controlling the yarn carrier enabling a gripper Axminster loom to operate at greater speeds than hitherto with the Jacquard selection bars in a horizontal orientation.

Claims (5)

1. CLAIMS 1. A gripper Axminster carpet loom in which each gripper has associated therewith a respective elongate yarn carrier having means for locating a plurality of yarns at intervals along its length, each carrier being axially displaceable to present a chosen yarn to an associated gripper according to the longitudinal position of the carrier, means for the axial movement of the carrier comprising an engagement device movable under the control of the Jacquard or other patterning system and an associated entrainment device comprising an elongate member extending generally in the axial direction of its associated carrier and pivoted thereto, characterised in that the carrier is provided with two sets of notches corresponding to the number and pitch of yarns in a yarn platform, and a setting bar is provided for each set of notches, each setting bar being operatable to engage with a respective notch and arrest the motion of the carrier in a predetermined position.
2. 2. A loom as claimed in claim 1 wherein, in addition to the two sets of notches equalling the number of yarns supplied in each yarn platform, there is provided an extra notch set at a defined distance greater than the yarn carrier pitch towards the pivot.
3. 3. A loom as claimed in either of claims 1 or 2 in which there are 12 apertures in each yarn platform and twelve notches in each set.
4. 4. A loom as claimed in any of claims 1 to 3 in which the selection bars are oriented horizontally.
5. 5. A loom substantially as hereinbefore described with reference to the accompanying drawings.