US3901284A

US3901284A - Weft carrier for a shuttleless loom

Info

Publication number: US3901284A
Application number: US430876A
Authority: US
Inventors: Christian Riolet
Original assignee: Saurer Diederichs SA
Current assignee: Saurer Diederichs SA
Priority date: 1973-01-22
Filing date: 1974-01-04
Publication date: 1975-08-26
Anticipated expiration: 1992-08-26
Also published as: IT1002074B; JPS53131070U; JPS5398868U; FR2214774B1; ES420959A1; GB1407383A; CA990182A; BE807484A; CH573488A5; JPS49108368A; DE2401032A1; DE2401032B2; FR2214774A1; DD109678A5; CS179998B2

Abstract

A shuttleless loom has a pair of weft carriers which reciprocate toward and away from each other from opposite sides of the shed to meet in the shed center and pass a weft filament from the feed carrier to the pickup carrier. Each carrier telescopes in a guide outside the shed which is provided with an actuating formation which serves to move a gripper element away from a retaining surface against the force of a spring. A latch pawl is provided in each carrier to hold the element away from the surface so long as the carrier is outside the shed in order to allow the feed carrier to grip a new weft filament and to allow the pickup carrier to release the thread it has drawn through the shed. The retaining surface of the feed carrier is spring-biased to pivot away from the clamping element when released, and the retaining surface of the pickup carrier grips the thread with a flap pressed by the clamping element against this surface.

Description

United States Patent 1 [111 3,901,284

Riolet Aug. 26, 1975 1 1 WEFT CARRIER FOR A SHUTTLELESS Primary Examiner-Henry S. Jaudon ,()()M Attorney, Agent, or FirmKarl F. Ross; Herbert [75] Inventor: Christian Riolet, Saint-Chef, France Dubno [73] Assignee: Saurer Diederichs S.A., [57] ABSTRACT Bourgom-Jalheu (lsere), France A shuttleless loom has a pair of weft carriers which re- [22] Filed: Jan. 4, 1974 Appl. No.: 430,876

ciprocate toward and away from each other from opposite sides of the shed to meet in the shed center and pass a weft filament from the feed carrier to the pickup carrier. Each carrier telescopes in a guide outside the shed which is provided with an actuating formation which serves to move a gripper element away from a retaining surface against the force of a spring. A latch pawl is provided in each carrier to hold the element away from the surface so long as the carrier is outside the shed in order to allow the feed carrier to grip a new weft filament and to allow the pickup carrier to release the thread it has drawn through the shed. The retaining surface of the feed carrier is spring-biased to pivot away from the clamping element when released, and the retaining surface of the pickup carrier grips the thread with a flap pressed by the clamping element against this surface.

10 Claims, 14 Drawing Figures PATENTEDAUGZBIQYS SIYKET 1 Or" 5 WEFT CARRIER FOR A SHU'ITLELESS LOOM FIELD OF THE INVENTION The present invention relates to a shuttleless loom. More particularly this invention relates to a weft carrier for inserting a weft thread in the shed of a shuttleless loom.

BACKGROUND OF THE INVENTION A type of shuttleless loom is known which has a pair of weft carriers each displaceable from a respective side of the shed into the shed center. The feed carrier grips and carries the end of a weft thread from one side of the shed to the shed center where this end is picked up by the takeup carrier and pulled to the other side of the shed.

Each carrier is usually formed as a pair of telescoping elements the outer of which is fixed outside the shed and the inner of which can move in and out in the shed for each pick. Each of these inner elements is formed substantially as a needle with a gripper at its end. The gripper of the feed needle must be opened as it is pulled out of the shed so as to receive a weft-thread end, and the gripper of the takeup needle must be opened as this element reaches the shed end so as to release the weft thread, leaving the weft in the shed for consolidation in the weave by battening.

This opening and closing of the grippers must take place at a very precise instant for proper weaving and they must not open other than at this instant. In order to prevent dropping of weft threads it is usually necessary in such looms to operate at a low speed in order to insure proper engagement and release of the weft thread. It has also been suggested to slow the operating cycle down just at the instant when the grippers are to be actuated. Neither of these arrangements has proven useful in practice, as both slow down production speed considerably.

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide an improved shuttleless loom.

Another object of this invention is the provision of an improved weft carrier for a shuttleless loom.

A further object is the provision of feed and takeup carriers which can operate at high speeds to insert a weft thread.

SUMMARY OF THE INVENTION These objects are attained according to this invention in a shuttleless loom having weft-carrier needles each provided with a support having a retaining surfaceand a clamping element pivotal on the support and engage able with the surface to grasp a thread. A spring normally urges the element against the surface to hold the thread. The carrier guide outside the shed is provided with an actuating formation which engages mechanism in the carrier adapted to pivot the element away from the surface when the support is at the end of the shed. Both of the carriers are constituted in this fashion so that when the feed carrier arrives at its end of the shed it opens to pick up a new weft, and when the takeup carrier arrives at its end of the shed it opens to release the thread now lying in the shed.

In accordance with another feature of this invention the formation on the outside guide is engaged by a roller on an end of one arm ofa two-arm lever which constitutes the element and whose other arm is engageable with the surface. Means is provided which is operated by the actuating formation on the outer element to lock the element in the open position so long as the carrier is outwardly beyond a predetermined position at the shed edge. Thus the gripper is locked open once it leaves the shed to allow a new thread to be laid in it or to allow the previously held thread to rest in the shed, whereupon the fabric can be beaten up and the grippers advanced toward each other within a newly formed shed again, with the feed carrier grasping the new thread and the takeup carrier pulling it through.

This locking mechanism comprises, according to this invention, a pivotal two-arm lever having a laterally opening cutout in which is receivable an extension or end of the clamping element. The locking lever can rock between an unlocked position wherein the extension is free of the cutout, and a locked position with the extension received in the cutout and the element immobilized. The ends of the two arms of this lever are actuated by a camming formation to move them between these positions, with the locking lever remaining in the locked position so long as the carrier is beyond the predetermined change-over position.

In accordance with another feature of the present invention the support carries a pivotal abutment which constitutes the retaining surface and is engageable with the clamping element to grasp the weft filament, and which is spring-biased into a position tending to free the filament. In this manner as soon as the clamping element pivots back the abutment will pivot in the opposite direction to open widely. Thus the element and the abutment meet flatly to grasp the filament.

BRIEF DESCRIPTION OF THE DRAWING The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a side-elevational view of the feed carrier according to this invention;

FIGS. 2 and 3 are sections taken along respective lines Il-II and IIIIII of FIG. 1;

FIGS. 4 and 5 are views similar to FIG. 2 illustrating the feed carrier in two other positions;

FIG. 6 is a side elevational view of the pickup carrier according to the present invention;

FIG. 7 is a top view of the carrier of FIG. 6; FIG. 8 is a section taken along line VIII-VIII of FIG.

FIG. 9 is a view similar to FIG. 7 illustrating the pickup carrier in another position;

FIGS. 10, l1, and 12 are views similar to FIG. 2 showing another feed carrier according to this invention; and

FIGS. 13 and 14 are side views of another pickup carrier in accordance with the present invention.

SPECIFIC DESCRIPTION As shown in FIGS. l9 the weft inserter according to the present invention comprises a feed carrier 1 having a head 2 and telescopically slidable within a fixed outer guide tube 3, and a pickup carrier 4 having a pickup hook 5 and telescopically slidable in a fixed guide tube 6. Both

tubes

3 and 6 are formed with respective actuating formations 7 and 7'.

The feed carrier 1 shown in FIGS. l-5 has a gripper lever 8 pivoted at 9 and formed with an end 11 that engages in abutment 12 pivoted at 13. A compression spring pivots the lever 8 clockwise into engagement with the abutment 12 and a hairpin spring 14 serves to pivot the abutment element 12 in the same direction so as normally to pull the two apart to form an open nip or mouth 46 (FIGS. 4 and 5). The spring force of spring 10 is greater than that of spring 14 so that in the absence of external forces the two

elements

11 and 12 lie together as a pair of gripping jaws (FIGS. 1 and 2). When the lever 8 is rotated counter-clockwise the element 12 is freed as shown in FIG. 4 to spread these two

jaws

11 and 12 and form a thread-receiving notch 46.

The other arm 19 of two-arm lever 8 carries a roller 20 which is engageable with the camming formation 7 so that, when the feeder head 2 is pulled back into the tube 3 as shown in FIG. 4, this roller 20 is pressed up to compress the spring 10 and rotate the lever 8 counterclockwise. The other arm 19 of the lever 8 is provided with an extension 19 pivoted at 47 on the lever 8 and adjustable by means of an eccentric screw so as to allow changing of the position of the extension 19' on the lever 8. The camming formation 7 here is formed with a short leading inclined ramp 7a, a flat central region 7b parallel to the tube 3 and the direction of displacement of the carrier 1, and another ramp 7c to the other side of the portion 7b.

In addition a locking pawl 22 is pivoted at 21 on the carrier and has a pair of

arms

22a and 22b engageable with the formation 7. This locking pawl 22 has a formation 23 in the form of a notch open toward the arm 19 in which another formation, here an extreme end 24 of this arm 19 is engageable. Thus as the feed carrier 1 moves back in the tube 3 the arm 22a is first cammed up, then the roller 20 as shown in FIG. 4. Subsequently the arm 22b is cammed up as shown in FIG. 5 to catch the end 24 in the cutout 23 so that even though the roller 20 is no longer in contact with the formation 7 the lever 8 is held in the open position. The stretch 7b has a length L which is shorter than the distance between the ends of

arms

22a and 22b. In this manner the pawl 22 is rocked first in one direction, then in the other. On displacement in the opposite direction the arm 22a is cammed up to free the end 24, and as shown in FIG. 2 this end 24 then lies against the pawl 22 to prevent it from catching and locking the lever 8.

The carrier head 2 as shown in FIG. 3 has a generally rectangular-section housing 42 which has on its horizontal lower front wall a point 43 and another point 44 on its upper horizontal front wall, which is slightly in back of the point 43. In addition the housing has a profiled lateral extension which prevents the head 2 from catching on weft threads perpendicular to the telescoping parts 1 and 3.

The pickup head 5 shown in FIGS. 6-9 is basically a hook. The two-arm lever 8' has an end 11 which presses a flap constitued by a short leaf-spring element 15 carried on a pin 16 against a fixed portion 12 (FIGS. 6 and 7). The weft thread indicated at T is caught between the jaws 11 and 12'. In all other respects the pickup carrier 5 is substantially identical to the feed carrier 2, with primes being added to the reference numerals where the structure is functionally the same. The pickup carrier 5 opens (FIG. 9) as it comes to the edge of the shed so as to release the weft thread in this shed.

FIGS. l0l2 show an arrangement substantially identical to that of FIGS. 1-5 except that the lever 8 is provided with an eccentric screw 25" having an off-center roller gudgeon 34 engaging in a crescent-shaped hole 33 in a pawl 31 pivoted at 32. This pawl 31 is formed with two

flats

48 and 50 and a tooth 52. The camming formation 7" is formed with two teeth 30 so that when the carrier 2 slides into the tube 3 these teeth 30 en gage and rotate the pawl 31 through substantially thereby camming up the roller 34" with the cam slot 33 that is not centered on the pivot 32. A holding element 36 pivoted at 37 has a flat surface 49 which lies when the nip 46 is closed against the surface 50 and which lies when the nip 46 is opened against the flat 48. A resiliently crushable body 38 lies between this element 36 and an ear 39 formed on the housing of the carrier 1 so as to urge the surface 49 against the disk 31 and hold this element against rotation from either of the positions illustrated in FIGS. 10 and 12. Thus the nip 46 will only open or close when the tooth 52 crosses over the teeth 30. This arrangement can also be employed on the carrier 5 as shown in FIG. 13.

FIG. 14 shows how a hairpin spring 40 can be used in place of the pivotal lever 36 and its biasing body 38.

I claim:

1. A weft carrier for inserting a weft in a shed of a shuttleless loom having a tubular carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising:

a support telescopingly displaceable in said tubular guide into and out of said shed and having a retain ing surface;

a gripping element pivoted on said support and engageable with said surface for pinching a weft thread against said surface;

a spring between said support and said element biasing said element against said surface; and

actuation means wholly carried in said support connected to said element and engageable with said formation for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed.

2. The carrier defined in claim 1 wherein said formation is a camming ramp and said actuation means includes a roller on said element and engageable with said ramp.

3. The carrier defined in claim 2, further comprising means on said support for locking said gripping element in an open position spaced from said surface on displacement of said support from said shed with said actuation means in engagement with said formation.

4. The carrier defined in claim 3 wherein the locking means includes a pivotal pawl engageable with said formation and with said element.

5. The carrier defined in claim 4 wherein said pawl is formed with a cutout, said element having an end engageable in said cutout.

6. The carrier defined in claim 1 wherein said support is provided with a displaceable flap engageable with said surface, said element being engageable with said flap to press same against said surface.

7. The carrier defined in claim 1 wherein said support comprises a housing of generally rectangular section.

8. A weft carrier for inserting a weft in a shed of a shuttleless loom having a carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising:

a support displaceable on said guide into and out of said shed and having a retaining surface;

a gripping element pivoted on said support and engageable with said surface for pinching a weft thread against said surface, said formation being a camming ramp;

a spring between said support and said element biasing said element against said surface;

actuation means on said support connected to said element and including a roller engageable with said formation for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed, said formation being at least one tooth and said actuation means including a pivotal pawl at least partially formed as a sector meshable with said tooth.

9. A weft carrier for inserting a weft in a shed of a shuttleless loom having a carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising:

a support displaceable on said guide into and out of said shed and having a retaining surface, said formation being a camming ramp;

actuation means on said support and including a roller mounted on said element and engageable with said ramp for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed; and

means on said support including a pivotal pawl engageable with said ramp and with said element for locking said gripping element in an open position spaced from said surface on displacement of said support from said shed with said actuation means in engagement with said formation, said pawl being displaceable between a locking position securing said element in said open position and an unlocking position permitting pivoting of said element, said carrier further comprising resilient biasing means for releasably holding said pawl in said locking and unlocking positions.

10. A weft carrier for inserting a weft in a shed of a shuttleless loom having a carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising:

actuation means on said support connected to said element and engageable with said formation for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed, said support being provided with a pivotal abutment constituting said surface, said carrier further comprising spring means for resiliently biasing said abutment away from said element.

Claims

1. A weft carrier for inserting a weft in a shed of a shuttleless loom having a tubular carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising: a support telescopingly displaceable in said tubular guide into and out of said shed and having a retaining surface; a gripping element pivoted on said support and engageable with said surface for pinching a weft thread against said surface; a spring between said support and said element biasing said element against said surface; and actuation means wholly carried in said support connected to said element and engageable with said formation for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed.

8. A weft carrier for inserting a weft in a shed of a shuttleless loom having a carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising: a support displaceable on said guide into and out of said shed and having a retaining surface; a gripping element pivoted on said support and engageable with said surface for pinching a weft thread against said surface, said formation being a camming ramp; a spring between said support and said element biasing said element against said surface; actuation means on said support connected to said element and including a roller engageable with said formation for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed, said formation being at least one tooth and said actuation means including a pivotal pawl at least partially formed as a sector meshable with said tooth.

9. A weft carrier for inserting a weft in a shed of a shuttleless loom having a carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising: a support displaceable on said guide into and out of said shed and having a retaining surface, said formation being a camming ramp; a gripping element pivoted on sAid support and engageable with said surface for pinching a weft thread against said surface; a spring between said support and said element biasing said element against said surface; actuation means on said support and including a roller mounted on said element and engageable with said ramp for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed; and means on said support including a pivotal pawl engageable with said ramp and with said element for locking said gripping element in an open position spaced from said surface on displacement of said support from said shed with said actuation means in engagement with said formation, said pawl being displaceable between a locking position securing said element in said open position and an unlocking position permitting pivoting of said element, said carrier further comprising resilient biasing means for releasably holding said pawl in said locking and unlocking positions.

10. A weft carrier for inserting a weft in a shed of a shuttleless loom having a carrier guide outside said shed operatively engageable with said carrier and provided with an actuation formation, said carrier comprising: a support displaceable on said guide into and out of said shed and having a retaining surface; a gripping element pivoted on said support and engageable with said surface for pinching a weft thread against said surface; a spring between said support and said element biasing said element against said surface; actuation means on said support connected to said element and engageable with said formation for pivoting said element against said spring away from said surface on displacement of said support to the end of said shed, said support being provided with a pivotal abutment constituting said surface, said carrier further comprising spring means for resiliently biasing said abutment away from said element.