US3796236A

US3796236A - Weft thread inserting means

Info

Publication number: US3796236A
Application number: US00312890A
Authority: US
Inventors: H Kamp
Original assignee: W Schlafhorst AG and Co
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 1971-12-09
Filing date: 1972-12-07
Publication date: 1974-03-12
Anticipated expiration: 1991-03-12
Also published as: BE792510A; JPS4864259A; CH545362A; DE2160998A1

Abstract

A device for inserting weft threads in looms having stationary supply spools includes a conduit disposed between the warp threads of the shed and through which the weft threads are passed by on air stream passing through the conduit. A plurality of segments having weft thread egress slots are disposed adjacent one another and sleeves are mounted on the segments for movement parallel to the direction of the weft thread to connect the segments to form the closed conduit.

Description

Unite States Patent Kamp Mar. 12, 1974 WEFT THREAD INSERTING MEANS 3.416572 12/1968 Giavini 139/126 W l 9 [75] Inventor: Heinz Kamp, Rickelrath, Germany 1412763 [1/1968 ueger 3 H26 [73] Assignee: i g Primary Examiner-Henry S. Jaudon one eng 8 ac ermany Attorney, Agent, or Firm-Herbert L. Lerner [22] Filed: Dec. 7, 1972 [2]] Appl. No.: 312,890 [57] ABSTRACT [30] Foreign Application Priority Data A device for inserting weft threads in looms having D 9 1971 G 2160998 stationary supply spools includes a conduit disposed ermany between the warp threads of the shed and through which the weft threads are passed by on air stream 139/126 zi i j gi passing through the conduit. A plurality of segments having weft thread egress Slots are disposed adjacent [58] Flew of Search 139/122 Z;B one another and sleeves are mounted on the segments for movement parallel to the direction of the weft thread to connect the segments to form the closed [56] References Cited Conduit UNITED STATES PATENTS 1/1971 Svaty 139/127 10 Claims, 6 Drawing Figures PATENIEDMAR 12 I974 SHEET 1 OF 3 FIGB Pmmwaam Ian I 3.796236 sum g or s WEFT THREAD INSERTING MEANS The invention relates to a device for inserting weft threads in looms equipped with stationary supply spools. The weft threads are passed by means of an air stream through the openings of a multiplicity of segments which are arranged side by side in rows and which are disposed between the warp threads of the shed and which have a weft-thread egress slot that can be closed.

In such devices the weft threads drawn from stationary supply spools disposed outside the shed are passed into a shed having a low height. The segments extending into the shed are arranged and distributed at regular intervals over the entire width of the web. The existing open space between the segments serve to pass therethrough unimpeded, individual warp threads. As soon as a weft thread has been carried across the width of the web, it is carried to the dividing point of the shed through the weft-thread egress slots of the segments and looped at the selvage of the web.

In one known device of the type described hereinabove, the weft-thread egress slots of the segments can be closed, whereby each segment is provided with a guide opening closed in on itself for the weft thread. Uncontrollable breaking-out of the latter during the carrying-in, particularly over large web widths, is thereby prevented. Such a device, however, suffers from the disadvantage of considerable air losses in the area of the spaces between the individual segments. To correct this shortcoming, an arrangement has become known which firmly encloses the warp threads by two lengthwise sections which are bent in a U-shape configuration. The two sections are movable against each other and have side walls with tongues and gaps forming a shed, and which produces in'this manner within a smaller section of the shed a space closed on all sides through which the weft thread is drawn. In this, as well as in the previously described arrangement, the wellknown disadvantage remains that in the free-flight of the weft threads, the latter loose part of their twist as they are carried in, so that the finished woven goods have undesirable and uncontrollable effects. A further disadvantage of the last-mentioned device resides in the favt that a considerable mechanical effort is required to realize a design selection of reasonable and practical effect.

' Looms are also known in which, in order to avoid loss of twist, the weft thread is gripped by means of a gripper shuttle and is carried in or guided in segments in a similar manner through a small shed. In such known looms the gripper shuttles are driven through the row of segments, and thereby through the shed, by means of mechanical impact devices. The disadvantage of these known devices resides in the high initial acceleration in launching the gripper shuttle and the strain on the weft-thread material connected therewith. Finally a loom is also known in which a weft thread is carried in by a cartridge which is comparable to a transport element with a gripper shuttle. The cartridge itself is propelled by an air blast through a weft tube attached laterally to the web and subsequently, without additional guide elements, through the warp threads which form the shed. Apart from the fact that the trajectory of a free-flight projectile causes difficulties with wider webs, the noise produced in the launching of a cartridge constitutes a considerable nuisance. It is an obother to form a closed through passage. With such a de vice it is possible to permit a number of free-standing segments to swing into the warp threads of a shed as heretfore, or also viceversa, to let warp threads immerse into the space between stationary segments, and yet to establish a single closed tube from the many freestanding segments within the shed in spite of this indispensable requirement and the resulting interference between warp threads and segments. With such a tube, the sleeves can serve, at the same time, to close the weft-thread egress slots of the individual segments. In this manner, an insertion channel is formed for the free-flight weft thread which operates without air losses and considerably reduces the air requirement for a loom. While being carried in, the weft thread cannot collide with its front end nor at any point of its length with segment interspaces or break out laterally at these points.

As previously mentioned, the segments arranged according to the invention can be arranged stationary and the warp threads of the shed can dip into the spaces between the segments. However, it is also possible to permit the segments to swing into and out of the spaces between the warp threads of a shed. In such a case, the segments are preferably connected with the sley. In either case, however, it is particularly advantageous if, according to a further feature of the invention, the sleeves connecting the segments with each other are coupled for the purpose of opening and closing the weft-thread egress slots as well as the spaces between the segments, with actuator elements for the opening and closing motions which are controlled by the main shaft of the loom synchronously with the formation of the shed.

The device according to the invention can, however, be used to particular advantage also in looms in which the weft threads are inserted into the shed by gripper shuttles. According to a further feature of the invention, the aforesaid is achieved by providing an arrangement whereby the segments, which can be closed to form a tube by means of the sleeves, are connected to a device to supply the interior of the tube with a suction or compressed air stream for transporting a gripper shuttle back and forth. Apart from the known advantages for the weft material to be woven, such as the elimination of the untwisting effect and of the poor guidance reliability during insertion, it is possible by connecting a suction or compressed air stream to the segments which are closed to form a tube, to lead a gripper shuttle with its weft thread through the tube and to return the gripper shuttle to the launching side after looping the weft thread at the web. According to a further advantageous feature of the invention, the actuating elements for the opening and closing motion the gripper shuttle in the tube formed by the segments and sleeves. With such an arrangemtn it is possible to obtain the advantageous possibility over a mechanical impact mechanism of altering the flight velocity of the gripper shuttle by continuous or section-wise opening or closing of the weft-thread egress slots as well as the spaces between the segments, thereby controlling the suction or compressed air stream within the tube and in turn, thereby controlling the velocity of the gripper shuttle. In this manner it is possible, for example, to impart to the gripper shuttle a gradual acceleration and to exert, a braking action on it at the end of the insertion travel, whereby the stress on the weft thread can be very considerably reduced.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention is illustrated and described in relationship to specific embodiments, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is an exploded view of a segment of a weft thread inserting device according to one embodiment of the invention.

FIG. 2 is a perspective view of the segment shown in FIG. 1 but with the parts assembled and in a condition wherein the weft-thread egress slot is open and the sleeve is pushed in.

FIG. 3 is a perspective view of the segment shown in FIG. 1 but in a condition wherein the weft-thread egress slot is closed and the sleeve is pushed out.

FIG. 4 is a elevational view of a shed with actuating elements for opening and closing the segments.

FIG. 5 is a sectional view of a closed row of segments and showing a gripper shuttle in the starting position.

FIG. 6 is a side view, on a smaller scale, of the gripper shuttle magazine shown in FIG. 5.

Referring to the drawings, FIG. 1 shows an exploded view ofa segment 1 with the various parts arranged relative to a segment ring 2 to indicate particularly clearly which parts are moved during the opening and closing operations. The segment ring 2 is firmly mounted on a segment holder 3 of which only the upper part is shown in FIGS. 1, 2 and 3. A segment attachment 4 is immovably fastened on the segment ring 2 by means of two pins 8 which are driven into respective holes 8, in the segment ring 2. The segment attachment 4 with its roof-shaped incline facilitates the dipping of the segment 1 into the group of warp threads of the shed. A sleeve 5 is located in in front of the segment ring 2. The sleeve 5 is rotatably supported in the segment ring 2 and can be displaced parallel to the direction of the weft. The sleeve 5 has a turning arm 6 and a weftthread egress slot 7 as will be further explained. In addition the sleeve 5 has a shoulder forming a sealing surface 9 as well as two pins 10 and 11. The pin 10 as well as the turning arm 6 move, in the assembled condition, in

elongated slots

13 and 12 respectively machined into the segment ring 2 with each

elongated slot

13, 12 having the same pitch angle, the arrangement be such that a rotary motion of the sleeve 5 causes an axial displacement of the sleeve 5. The turning arm 6 is led not only through the elongated hole 12, but also through a further elongated slot 14 of a segment part 15 which fits into a recess 16 which is machined at the inside surface of the segment ring 2. Thus the segment part 15 in this m,nner is supported displaceably, like the sleeve 5, in the weft direction, so that part of the weft-thread egress slot 7 of the sleeve 5 is sealed off by the segment part 15 which protrudes from the segment ring 2. This condition is shown in FIG. 3.

The part of the weft-thread egress slot 7 in the segment ring 2 which cannot be covered up by the sleeve 5 is closed by means of a segment part 17 which is inserted into a further recess 18 in the segment ring 2 and which can be moved back and forth by the pin 1 ll of the sleeve 5. In this regard the pin 11 engages an elongated slot 19 in the segment part 17.

Pins

20 and 21 on segment part 17 engage short

elongated hole guides

22 and 23 respectively, in segment ring 2, the arrangement being such that the segment part 17 moves only straight or circumferentially inside the recess 18 during displacement of pin 11. The position of the segment part 17 with the weft-thread egress slot 7 closed can be seen particularly clearly in FIG. 3.

A cover strip 24 has an elongated slot 25 through which two pins with heads 27 are press-fitted into holes 26 in segment ring 2. The two pins having heads 27 provide the longitudinal guidance for the cover strip 24 and serve to seal the elongated hole 12 in the segment ring 2. An elongated slot 28 in the cover strip 24 serves as the passage opening for the turning arm 6.

FIG. 2 shows the segment 1 in the condition in which the weft-thread egress slot 7 in the segment ring 2 as well as the weft-thread egress slot 7 in the sleeve 5 are conincident and thereby form a single opening for the passage of the weft-thread. The shoulder of the sleeve 5 which is provided with the sealing surface 9 rests, in the FIG. 2 position, firmly against the segment ring 2. In the condition of the segment shown in FIG. 2, it becomes possible to dispose or immerse it into the warp or to swing it out of the shed.

If the turning arm 6 is swung by means of an arrangement as shown in FIG. 4 in the direction of the arrow 28 (shown in FIG. 2) the condition of the segment 1 shown in FIG. 3 will result. In this latter condition, the sleeve 5 is pushed out of the segment ring 2 so far that its sealing surface 9 comes to rest at the lateral surface of an adjacent segment ring (not shown in FIG. 4, but shown in FIG. 5) and the weft-

thread egress slots

7 and 7 are closed. In the relative condition of all movable parts shown in FIG. 3, a completely closed tube formed by the segment rings 2 and the sleeves 5 is produced through which a free-flight weft-thread can be blown, or a weft-thread carried by a gripper shuttle can be transported by means of a suction or compressed air stream.

FIG. 4 shows a shed formed by warp threads 29 which at their deviding point become a woven web 30. At the dividing point of the shed is a weft-thread 31 which has been pushed against the web. As already indicated, the segments 1 are mounted on segment holders 3 and can be pivoted about the center of a shaft 32, (FIG. 4) in the direction of the double arrow 33 by means of a reed 34, synchronously with the motions for the formation of the shed aswell as the weft thread loop. Each segment arm 8 has an extension 3' on which is pivoted an angle lever 35 which, in turn, is movably connected to the turning arm 6 of a segment 1 by means of an elongated slot 36 in angle lever 35. The angle lever 35 has a portion 38 which rests, through the biasing force of a tension spring 37, on the circumference of a cam 39. The cams 39 of a row of segments are fastened to a shaft 40 which is rotatably supported in the segment holders 3. The shaft 40 is driven in the same manner as the motions for the formation of the shed as well as the weft-thread looping from the main shaft of the loom. The opening and closing motions for the individual segments are derived from the cam 39. By suitable displacement of some cams 39' relative to each others, the opening and closing motions for all of the segment rings and sleeves arranged in one row of segments need not occur simultaneously, but the possibility exists to open the weft-

thread egress slots

7, 7 as well as the spaces between segments 1 bridged by the sleeves 5, in a controlled pattern and to thereby change the air flow in the tube formed by the segments. Air flow changed in this manner can be used, as already mentioned, for decelerating and accelerating the gripper shuttle within a row of segments. Of course, all laminations and the spaces between them can also be opened or closed simultaneously. In such a case it is sufficient to place the ends of the turning arms 6 in a U-shaped bar to permit the latter to be moved by a few angle levers 35 and an equal number of cams 39. FIG. 5 shows the segment rings 2 with their sleeves 5 fitted together to form a closed tube when the turning arms- 6 are actuated in the appropriate position as previously described. The tube formed by the segments 2 and the sleeves 5 is connected, in the example of the embodiment shown in FIG. 5, with a resiliently adjoining launching tube section 43 in which a gripper shuttle 41 is held in readiness. A weft thread 31 has been fed to the gripper shuttle 41 in a manner known per se. The launching tube section is part of an also known gripper shuttle magazine 44 (FIG. 6) which can be equipped, for example, with six receiving and launching stations for gripper shuttles and which is arranged at both ends of the tube of segments. The gripper shuttle magazine 44 has a connecting hold 45 for compressed or suction air as well as alternatingly supplied channels 42 for the back and forth transport of the gripper shuttles.

FIG. 6 shows a circular gripper shuttle magazine 44 in which a launching tube section 43 has assumed a position relative to the shed, which is suitable for carrying-in the weft thread. The gripper shuttle magazine 44 is advantageously driven in the direction toward the dividing point of the shed. As previously mentioned, the gripper shuttle 41 can be returned within the tube formed by the segments and the sleeves as well as in a separate tube outside the shed. For this purpose, a smooth tube may be suitably aligned, for example, in

position 43' with the launching tube segments 43, which can also be supplied with a stream of suction or compressed air.

I claim:

1. Device for inserting weft threads in looms having stationary supply spools wherein the weft threads are carried by an air stream passing through a conduit disposed between the warp threads of the shed, comprising a plurality of segments disposed adjacent to one another and having aligned openings, said segments having means defining a weft thread egress slot, each of said segments having sleeves movably parallel to the direction of the weft thread and which are operable to connect said segments to form a closed through conduit.

2. Device according to claim 1 wherein said sleeves are operable to close said means defining the weft thread egress slot.

3. Device according to claim 1 wherein said loom has a main drive shaft, actuating means actuated by said main drive shaft, and complying said sleeve and said actuating means whereby said latter means is operable to effect opening and closing of said means defining the weft thread egress slot.

4. Device according to claim 3 comprising a gripper shuttle disposed in said conduit, and means supplying said conduit with a stream of suction air or compressed air for transporting said gripper shuttle back and forth within said conduit.

5. Device according to claim 4 comprising means operably associated with said actuating means for controlling the opening and closing motion of said means defining a weft thread egress slot as a function of the distance travelled by said gripper shuttle in said conduit formed by said segments and sleeves.

6. Device according to claim 1 wherein said segments are spaced from one another to permit warp threads to pass therebetween, said space being closed when said sleeves are moved to connect said segments to form said closed through conduit.

7. Device according to claim 1 wherein each of said segments comprises a ring element having a radial opening, and means mounted on said ring element movable circumferentially for closing said radial opening.

8. Device according to claim 7 wherein said sleeve has a radial opening which is operable to be aligned with said radial opening in said ring element.

9. Device according to claim 8, wherein circumferential displacement of said sleeve, effects axial displacement of said sleeve relative to said ring element.

10. Device according to claim 8 wherein means are mounted on said ring element for effecting closure of said radial opening in said sleeve.