US 3675687 A
A pneumatic thread preparing and presenting mechanism which is suitable for handling low twisted yarns in that the thread in its path from the storage cone to the weaving shed is exposed to relatively low tensions.
Claims available in
Description (OCR text may contain errors)
United States Patent Vermeulen et a]. 14 1 July 11, 1972  MECHANISM FOR PREPARING AND 58 Fleld olSearch ..139/122 R, 127 P; 66/125 PRESENTING SINGLE THREAD LENGTHS TO A WEFT DEVICE OF A  Ram CM WEAVING LOOM FOREIGN PATENTS 0R APPLICATIONS I 1 lnvemom Jan Antonius 6,616,526 5/1968 Netherlands ..139/121 P both of Deume, Netherlands 461,401 8/! 968 Switzerland ..139/121 P  Assignee: v M'chhdabflek L. m strike 477,58l 8/]969 Switzerland 139/127 P Deurne, Netherlands Primary Examiner-Henry S. Jaudon Filed: Attorney-Marshall & Yeasting l. N "8,043 [211 App 51 ABSTRACT  Foreign u u Prim-"y m A pneumatic thread preparing and presenting mechanism which is suitable for handling low twisted yarns in that the March 30, I971 Netherlands ..7003045 thread in its path f a storage cone to the weaving shed is exposed to relatively low tensions. 52 us. c1 ..139 127 P [51 1 Int. Cl. ..D03d 47/34 2 Claims, 4 Drawing Figures MECHANISM FOR PREPARING AND PRESENTING SINGLE THREAD LENGTI-IS TO A WEFI DEVICE OF A WEAVING LOOM BACKGROUND OF THE INVENTION The invention aims at providing a simplified mechanism for preparing and presenting measured single thread lengths to a weft device of a weaving loom, said mechanism being particularly suitable to be applied in weaving looms adapted for weaving with a false selvage such as occurs when weaving with various kinds of synthetic yarns.
More particularly the invention aims at providing a pneumatic thread preparing and presenting mechanism which is suitable for handling low twisted yarns in that the thread in its path from the storage cone to the weaving shed is exposed to relatively low tensions, as compared with the known mechanisms, and in general is spared in greater measure.
Various constructions of mechanisms serving for the preparation and presentation to a weft device of a weaving loom of measured thread lengths are already known. Said mechanisms, which mostly are adapted to the preparation of double thread lengths and to weaving with selvage, are relatively complicated in view of the many moving parts, the application of inserting needles and the special provisions connected with the launching of double thread lengths in two pieces of unequal length.
SUMMARY OF THE INVENTION The mechanism proposed by the invention is characterized by a first auxiliary nozzle which follows a thread feeding device, said nozzle having its exit opening directed to a first storing shaft for permitting a first thread loop to be received in said storing shaft, the leading run of said loop extending via a first thread clamp through a second auxiliary nozzle, the exit opening thereof being situated opposite to a second storing shaft for the reception into the said shaft of a second thread loop, the leading run of which extends to the main nozzle of the weft device, a second thread clamp as well as a cutting device being provided adjacent to the main nozzle. The thread clamps as well as the cutting device are controlled so that during the one half of a weaving cycle the first thread clamp is closed, the second thread clamp is open and the cutting device is inoperative a thread loop previously formed in the second storing shaft being inserted into the weaving shed by the main nozzle and a new" thread loop being at the same time inserted into the first storing shaft by the first auxiliary nozzle whereas in the other half of the same weaving cycle the first thread clamp is opened and the second thread clamp is closed, the thread loop formed during the previous half cycle in the first storing shaft being transmitted by the second auxiliary nozzle to the second storing shaft, whereas the cutting device is actuated at the transition from the first to the second half of the weaving cycle for cutting off the thread length inserted into the weaving shed by the main nozzle.
Preferably the nozzles are controlled so that the first auxiliary nozzle is actuated continuously, the second auxiliary nozzle only during the second half of the weaving cycle and the main nozzle only during the first half of the weaving cycle.
BRIEF DESCRIPTION OF THE DRAINING FIG. 1 is a diagrammatic view in perspective of a mechanism embodying the invention,
FIG. 2 is a fragmentary elevation of a conventional device for controlling the supply of air to a nozzle.
FIG. 3 is a fragmentary elevation of a conventional device for operating a thread clamp.
FIG. 4 is a fragmentary elevation of a conventional thread cutting device.
In the mechanism shown in the drawing, which mechanism is adapted to be mounted alongside a weaving machine, the weft thread 1 is drawn directly from a storage cone 2 and supplied via a pneumatically operating supply and breaking device 3, controlling the tension of the thread, to a set of measuring rolls 4a, 4b. The pneumatic supply and breaking device 3 is for instance constructed as described in the Dutch patent application 66l0l74, laid open for public inspection. From the measuring rolls 4a, 4b, the larger one 40 of which may be driven at a speed that is adjustable in correspondence with the width of the cloth to be woven, the thread is taken by a first auxiliary noule S of a known type which permits the thread to be received in the shape of a loop 6 into the storing shaft 7. If necessary the end 7' of the shaft 7 may also be connected to a suction device. The thread further moves via a first thread clamp 8 through a second auxiliary noule 9, which last mentioned auxiliary nozzle may likewise be of a known type and is adapted to permit, by means of a transporting air jet produced by it, the reception of a second loop 10 of the thread into the storing shalt II. If necessary also the end 11' of the shaft ll may be connected to a suction device which may be intermittently actuated. The leading run of the loop 10 moves via a guide 12 to the main noule l3 which has its exit opening situated before the weaving shed and is adapted to insert intermittently, that is at each revolution of the main shaft of the weaving machine, a length of the thread 1 into the weaving shed, said length being measured corresponding to the desired cloth width. The thread leaving the main nozzle 13 passes a second thread clamp 14 and a cutting device 15. The last mentioned device may be of any desired type, and may consist of a movable part 15' and a stationary part 17. Particularly when handling synthetic threads a cutting device may be used which operates by burning or melting the thread by means of heat.
In the embodiment shown the storing shafts 11 and 7 are axially aligned and at the transition between such shafts a screen 16 has been placed in order that the opposite air streams prevailing in the shafts may not influence each other.
The operation of the mechanism described above is as follows.
The drawing shows the mechanism in a phase in which the main noule 13 is about to insert the loop 10 (formed in the storing shaft 11) into the weaving shed via the thread clamp 14 (open at this moment), and via the inoperative cutting device 15. The thread clamp 8 is in closed position at this moment whereas the auxiliary nozzle 9 is not actuated.
At the end of the launching by the main nozzle I3 of the thread length corresponding to the loop 10 into the weaving shed, the thread clamp 14 is closed, controlled by a shaft 18 driven from the main shaft of the weaving machine, and the cutting device 15, which maybe similarly controlled by the shaft 18, is actuated to separate the weft thread length from the rest of the thread and to permit the beating up of said length into the cloth 19 during the second half of the weaving cycle by means of the reed 20. At the same time the auxiliary nozzle 9 is actuated by the opening of an air supply valve 21 controlled by the shaft 18, and the thread clamp 8, which is controlled like the clamp 14, is opened in order to transmit the loop 6 (formed during the launching that has just ended, by means of the continuously blowing" auxiliary nozzle 5, in the storing shaft 7) into the storing shaft 1 1. Thereafter the thread clamp 8 is again closed and the actuation of the auxiliary nozzle 9 is ended in order that the thread length formed in the shafi 11 may be inserted, with the thread clamp 14 opened, into the weaving shed by means of the main nozzle 13.
I. A wei't drawing device for presenting measured thread lengths to a weaving machine, comprising a continuously activated first auxiliary nozzle, mechanism for feeding a thread continuously to such nozzle, a first storage shalt arranged to receive a first loop of the thread discharged by such nozzle, a second auxiliary nozzle arranged to withdraw the leading run of such loop of thread from the first storage shalt, a first thread clamp located adjacent to the second auxiliary nozzle, a second storage shaft arranged to receive a second loop of the thread discharged by the second auxiliary nozzle, a main weftinserting blowing nozzle arranged to withdraw the leading run of the second loop of thread from the second storage shaft, and a second thread clamp and a cutting device through which clamp may be closed while the second auxiliary nozzle is active and the main blowing nozzle is inactive.
2. A weft drawing device according to claim 1 wherein the first and second storage shafts are so arranged that the leading run of the loop in the first storage shafi is in alignment with the trailing run of the loop in the second storage shaft.