Device for weft thread length measuring.

(54) Title of the invention: device for measuring the length of the weft thread:. on a weaving machine (57)

The weft yarn length measuring device of a weaving machine constructed according to the invention comprises at least two weft yarn supply units, each of which is associated with a weft yarn length measuring member (10) with conical circumferential surfaces (10a, 10b), at least two motors (5, 12) each adapted to wind the weft yarn around the conical threads. circumferential surfaces (10a, 10b) of the metering member (10), and weft yarn retention means (1.4, 16, 19, 20). to control the amount of weft yarn wound on the conical circumferential surfaces ("10a, 10b") and transfer the wound yarn in the direction of weft insertion. Rotational speeds of the respective motors (5, 12) and operation of the respective retention means (14,

16, 19, 20) the weft yarns are controlled by the control units (C1, C2) according to a predetermined weft yarn selection program. A non-contact winding sensor (31) can be associated with each yarn length measuring member (10); the weft threads wound on the metering member (10). The sensed signals are transmitted from the proximity sensor (31) to the control unit (C1), which commands the speed to the respective motors (5, 12) in order to compensate for any fluctuations occurring in the measured weft thread lengths.

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BACKGROUND OF THE INVENTION The present invention relates to a device for measuring the length of a weft thread on a weaving machine, comprising at least two weft yarn length measuring members associated with at least two weft yarn storage coils and provided with weft yarn winding areas associated with weft yarn retention means. the weft yarns are coupled to the drive motors.

A device for measuring the length of the weft thread corresponding to one weft picking and for temporarily storing the measured length of the weft thread is provided on the seal-free state, and in particular on the nozzle state. In a device of this type so far proposed in the art, the weft yarn fed from the weft yarn supply unit is wound to measure its length, and the weft yarn, the length of which has been measured, is provisionally stored in a wound state to be subsequently retracted for weft picking.

In a winding device of this kind, the weft yarn is wound onto the winding surface of the yarn length measuring element, for example a drum, and the length of the weft yarn wound thereon and its transfer to the weft yarn insertion direction are controlled by at least one pair of weft yarn retention pins. adapted to extend and retract into the winding surface prq. The weft yarn is usually guided through a feed tube adapted to rotate relative to the metering element, and is wound onto the winding surface of the element.

It should be noted that if only one type of weft yarn is fed from just a supply source and clogged to form a fabric, only one weft yarn length measuring unit is sufficient for this purpose. However, if the weft yarns are fed from two or more supply units, a number of weft yarn measuring units equal to the number of said supply units must be provided. For example, if two weft yarns are fed from two weft yarn supply units, two metering units are used. In this case, the feed rate of each weft yarn or the winding speed of each weft yarn to the metering element of each unit is half the winding speed if only one metering unit is used. (This speed will hereinafter be referred to as the normal winding speed.) This means that the length of each weft yarn is measured once per two weft pickings, the weft yarns being staggered alternately. This method of weft insertion is used not only to feed two weft yarns of different colors, but also to feed the same type of weft yarn from two weft yarn supply units to produce a uniform quality fabric and consisting of one type of weft yarn. This method of feeding the same type of weft yarn from multiple weft yarn supply units is known as weft blending.

The above-mentioned weft insertion method can be used in cases where three or more weft yarn supply units are used. For example, when three weft yarn supply units are used, the winding speed of each thread is one third of the normal winding speed and the length of each weft thread corresponding to one pick (hereinafter referred to as a predetermined length) is measured once every three weft pickings. whereby the measured lengths of the three weft yarns are gradually introduced. When four weft yarn supply units are used, the winding speed of each weft yarn is one quarter of the normal winding speed, and the length of each weft yarn equal to a predetermined length is measured once per four passes, the measured weft yarn length being staggered. The same applies if five or more weft yarn supply units are used. This method of weft yarn insertion is effective in cases where the weft yarns fed from the respective weft yarn supply units are different and are clogged alternately or when the aforementioned weft blending is performed to produce a uniform quality fabric. However, if weft yarns of two or more types are used and the weft threads of the same type are entered several times in succession, it would be necessary to arrange a number of weft yarn length measuring units equal to at least this number of weft threads in succession. .

In order to avoid this drawback, a weft length measuring device has been proposed which, in addition to the weft thread retention pin used on conventional devices, is provided with an auxiliary retention pin positioned closer to the fabric to be produced than the first retention pin for controlling the measured weft thread. in the direction of weft insertion, thereby allowing the weft thread of the same species to be inserted several times in succession (Japanese Laid-Open Patent Application No. 59740/1981). In this device, the weft yarns fed from the two weft yarn supply units are wound at appropriate constant speeds onto the winding surfaces of the respective weft yarn length measuring units. For example, if one of the weft yarns is stuck twice in succession, then the other yarn is stuck once, the winding speed of the first thread is equal to two thirds of the normal winding speed, while the winding speed of the remaining weft thread is one third of the normal winding speed.

In this method of weft insertion, it is assumed that when one weft is released and clogged with the auxiliary retention pin, one third of the predetermined length of the same weft thread is retained by the retention pin on the winding surface and one third of the predetermined length of the other weft. the thread is retained by the associated retaining pin on the associated winding surface. At the time of the next picking, the predetermined length of the first thread retained by the associated retaining pin on the winding surface is released and clogged by the retaining pins. At this time, two thirds of the predetermined length of the second thread are wound on the associated winding surface. At the time of the next weft picking, the length of the second thread is increased to the value necessary for one insertion (to a predetermined length), then this length of the second thread is released and clogged by the retaining pins. At this time, two-thirds of the predetermined length of the first thread are kept. In a further weft pick, the length of the first thread required for the next pick (predetermined length) is retained on the winding surface by the auxiliary retaining pin and one third of the predetermined length of the same thread is retained by the retaining pins on the same winding surface. Accordingly, it is sufficient to arrange only one auxiliary strand (the cutting pin) on the measuring unit of the length associated with said first thread.

If the two threads are staggered alternately in such a way that the same thread is stuck twice in succession, one auxiliary retaining pin may be provided on each metering unit. In this case, the winding speed of each weft thread is equal to half the normal winding speed.

However, in cases where the same thread fed from one supply unit is clogged several times in succession, there is a need to arrange a plurality of these auxiliary retaining pins on the metering unit allocated to the weft thread. For example, assuming one weft thread is inserted four times in succession, then the other weft thread is inserted three times in succession, then at a winding speed of the first weft thread equal to four sevenths of the usual speed, and at a winding speed of the second weft thread equal to With three sevenths of the usual speed, it is necessary that at the time when the first weft yarn is gradually being clogged, a plurality of the first weft yarn equal to at least two and two sevenths of a predetermined length is wound. This is because in this case, the length of the one thread on the winding surface is reduced to one and six seventh of a predetermined length for the second, pick, to one and three sevenths of a predetermined length for the third pick, and is equal to beforehand. set. for the fourth pick. In these circumstances, at the time the one thread is gradually being clogged, the thread length corresponding to the two threads and the other thread length, corresponding to the next two threads, must be retained by two separate pairs of auxiliary retaining pins.

The density of increasing the number of auxiliary retention pins with an increase in the number of successive weft threads fed from one supply source is undesirable as the construction of the weft thread metering device becomes complex. In addition, the above-described deficiency cannot be remedied if the weft thread is wound gradually.

Under these circumstances, there is a need for a weft yarn length measuring device allowing free choice of the weft yarn to be clogged without the need to replace mechanical parts.

Disadvantages of the known devices are essentially eliminated by the weft thread length measuring device according to the invention, characterized in that the drive motors coupled to the weft thread length measuring members are connected to the control means for controlling their speed of movement and the weft thread holding means are connected to control means for controlling their effectiveness. The rotational speeds of the drive motors, generally electric motors, and the functional timing of the respective weft yarn holding means can be varied by changing the weft yarn selection program and therefore without the need to replace mechanical parts, and a very varied weft pattern can be performed. The rotational speed of the motors is unlikely to be controlled in the manner required by the weft selection program, for reasons such as rotational resistance or unstable braking properties resulting in fluctuations in the measured weft thread lengths.

In an embodiment, it is preferable that the weft yarn length measuring member is formed by a drum mounted on a shaft, kinematically coupled to the drive motor.

A further object of the invention is that the holding means are formed by pairs of electromagnets associated with the weft yarn winding surfaces.

According to an advantageous embodiment of the invention, it is advantageous that each metering member is associated with a weft thread count sensor mounted on the weft yarn winding surface, which is connected to a control means for controlling the speed of movement of the metering member.

The invention will be more readily understood from the following description of preferred embodiments, illustrated by way of example only with reference to the accompanying drawings, in which: Figure 1 is a schematic plan view of one embodiment of a weft gauging system of the invention; Figure 2 are diagrams illustrating engine operation and winding and fouling 3 and 4 is respectively a plan view and diagrams similar to FIGS. 1 and 2 showing a modified embodiment of the invention.

In order to complete the description of one embodiment of the invention, FIGS. 1 and 2 are used in which reference numeral 1A denotes the weft yarn length measuring unit to which the weft yarn Y1 fed from the weft yarn supply unit 2A is wound and its length measured. Reference numeral IB denotes the weft yarn length measuring unit to which the weft yarn supply unit Y2 is fed from the weft yarn supply unit 2B and its length is measured. The units 1A and IB are similar in construction.

Referring only to the unit 1A, a rotatable support shaft 4 having a guide hole 4a on the weft yarn guide Y1 passes through the rotatably support member 3 mounted on some fixed parts, for example on the side of the weaving loom. The rotary support shaft 6 is rotated by a first motor 5, which is controlled by a functional command of the engine control unit C1, for example a microcomputer, giving command signals according to a predetermined weft selection program. On the front side of the support member 3, in the direction of the picking side of the weft thread, there is a fixed gear 6, on the front side of which the support element 7 is mounted, which in turn is fixed to the rotatable support shaft 4. On the support element 7, a winding tube 41 is arranged at an acute angle to the shaft 4. The winding tube 7 is mounted on the support. Hollow inside winding pipe no! it is connected to the thread guide opening 4a and its foremost part is located above the first conical circumferential surface 10a of the metering member 10, which will be described in the following. On the rotating support shaft 4, a holder 6 is formed on the customs side of the support element 7 for the purpose of relative rotation with the gear 9a. A metering member 10 having a weft yarn winding surface consisting of a first conical circumferential surface 10a and a second conical circumferential surface 10b and serving as a weft yarn length metering element, is mounted on a rotatable support shaft 4, on the front side of the holder.^for for relative rotation with the rotatable support shaft 4. A planetary gear 11 with an input planetary gear 11a engaged with the gear 6 and an output planetary gear 11b engaged with the gear 9a is mounted on the support element 7. The gear ratio between the gear 6 and the planet gear 11a is selected to be equal to the gear ratio between the gear 9a and the planet gear 11a. In this way, when the first engine is 5. in operation, to actuate the rotatable support shaft 4, not only the thread take-up tube 8 rotates, but also the planet gear 11 as a whole with the rotatable support shaft 4. The planetary gears 11a, 11b respectively engaged with the gear teeth wheels 9, 9a orbiting the rotatable support shaft 4, the metering member 10 remaining stationary without any rotation.

The rotating support shaft 4 of the weft yarn length measuring unit 1B is rotated by a second electric motor 12, which is controlled by a functional command of the engine control unit C1, issuing command signals according to the weft yarn selection program.

A first weft yarn retention member 14 that can be brought into contact with the first conical circumferential surface 10a by the operation of the electromagnet 13, and a second weft yarn retention member 16 that can be brought into contact with. the second conical circumferential surface 10b by the operation of the electromagnet 15 are arranged near the circumferential surface of the metering member 10 of the unit 1A. Similarly, the first weft yarn retention member 19 and the second weft yarn retention member 20 of the unit 1B may be contacted with the first conical peripheral surface 10a and the second conical peripheral surface 10b by the operation of the electromagnets 17, 18. The electromagnets 13, 15, 17, 18 are commands of the weft yarn restraint control unit C2, for example by a microcomputer, issuing command signals according to a predetermined weft yarn selection program.

Reference numeral 21 denotes a guide member for guiding the weft yarns Y1, Y2 in a known manner. Reference numerals 22, 23 denote the main nozzles used in a known manner for the individual insertion of the weft yarns Y1, Y2. During weft insertion, one selected nozzle of the two main nozzles 22, 23 is put into stand-by to weft thread length in accordance with the program for control unit C2 or the weft selection program for another control unit.

The main nozzles 22, 23 can be put into the weft thread clogging device by the device described in the co-pending patent application entitled Jet Weft Catch Device filed in the name of the present Applicant (Japanese Patent Application No. 149738/1982). Several electromagnets of this weft insertion device can optionally be excited according to the weft thread selection program for the control unit, as a result of which the selected nozzle from both main nozzles can be put into weft thread fouling.

CS 276583 E6

Suppose now that the first motor 20 is actuated according to a predetermined weft yarn selection program, so that the yarn winding tube 4 rotates about the metering member 10, which remains stationary as mentioned above. The weft yarn Y1 fed from the weft yarn supply unit 2A through the guiding aperture 4A and the winding tube 8 is wound onto the first conical circumferential surface 10a and its length is measured, the yarn being retained by the retention member 14, which according to the selection program the weft yarns in contact with the first conical circumferential surface 10a. Before the length of the weft yarn Y1 equal to a predetermined length is wound onto the first conical circumferential surface 10a, the first retaining member 14 is spaced from the first conical circumferential surface 10a so that the weft yarn W1 wound on the first conical circumferential surface 10a is shifted to a second conical peripheral surface 10b and retained by the second retention member 16 / in contact with the second conical peripheral surface 10b. While the first retaining member 14 is spaced from the first conical peripheral surface 10a, a further length of the weft yarn Y1 is fed to the second conical peripheral surface 10b in the above manner. When a yarn length Y1 equal to a predetermined length is wound onto the second conical circumferential surface 10b, the first retaining member 14 is contacted with the first conical circumferential surface 10a so that the weft thread length is provisionally disposed between the first and second retaining members 14/16. Y1 equal to a predetermined length. For this, when the second weft thread retention member 16 is spaced from the second conical circumferential surface 10b according to the weft selection programs, the weft thread Y1 is carried in the medium projected by the main nozzle 22 being in the picking position according to the weft selection program. is now clogged.

The weft yarn Y2 may be inserted similarly to the weft yarn Y1 in accordance with the weft yarn selection program.

Referring now to Fig. 2, a typical weft insertion will now be described using the first embodiment described above, wherein the weft yarns Y1, Y2 are clogged according to the weft insertion patterns or the weft selection program in such a way that yarn Y1 is clogged twice, yarn Y2. The thread Y1 is threaded four times, the thread Y2 is threaded twice, and finally the thread Y1 is threaded three times, respectively. It should be noted that in FIG. 2 the solid line represents the length of the unwound thread, while the dashed line represents the length of the measured thread.

Suppose now that the functional command of the engine control unit C1 issuing the command signals according to the weft selection program, the first motor 5 is actuated as indicated by the curve A1 in FIG. by determining the width of the fabric being fabricated and the number of covers per unit of time, and that the length of the weft yarn Y1 corresponding to a predetermined length is retained by the second retention member 16. and held on the second conical circumferential surface 10b. This operating state corresponds to the pivot angle 81 of the movable parts of the weaving loom, and at this time the first retaining member 14 'is brought into contact with the first conical circumferential surface 10a. When the second weft thread retention member 16 is spaced from the second conical circumferential surface 10b according to the weft selection program, the predetermined length of the weft thread Y1 previously deposited on the second conical circumferential surface 10b is retracted from the metering member 10 by the main nozzle 22 and clogged. ended at the hive 82 turning of the movable parts of the loom. During this time interval, the first motor 5 rotates at the speed V and the weft yarn Y1 is wound onto the first conical circumferential surface 10a as it is retained by the first retention member 14. Upon completion of the first weft picking, the second retention member 16 is brought into contact with the second conical peripheral surface 10b, while the first retention member 14 is spaced from the first crossbow CS 276583 B6 of the cylindrical peripheral surface 10a so that the yarn still wound on the first conical peripheral surface 10a. is converted to a second conical circumferential surface 10b. From this time, until the start of the second weft picking, the weft yarn winding Y1 continues to wind on the second conical peripheral surface 10b until a yarn length equal to a predetermined length is wound and deposited thereon. At the same time as the wound yarn so wound and stored begins to become clogged, the first motor 2 is smooth and slowed according to the weft selection program, as indicated by the curve 2Λ, and stops at the end of the third pick.

During the time when the first motor 5 is decelerated as described above, a second pick is made while the weft yarn length Y1 is wound on the metering member 10, equal to the yarn length for the fourth pick. Upon completion of the second weft pick, the engine control unit C1 operating the weft selection program command commands, the second motor 12 is accelerated from standstill as indicated by curve B1, slowed as indicated by curve B2, and stopped at the same time as the fourth weft pick is started. At the start of the third weft picking, the second retention member 20 associated with the metering unit IB is spaced from the second conical circumferential surface 10b so that the thread length Y2 deposited on the metering member 10 during the previous depositing cycle according to the weft insertion pattern E, shown in broken line in FIG. 2, indicating the inserted weft yarn Y2) is retracted and clogged by the main nozzle 23 from the metering member 10. During the time the second motor 12 is accelerated and decelerated as described above, the first retention member 19 is controlled according to the weft selection program such that the length of the weft yarn Y2 for the eighth weft pick is wound onto the metering member 10.

During the time the second motor 12 is accelerated and decelerated, i.e. from the end of the second weft picking to the start of the fourth weft picking, the second detent member 16 of the metering unit IA is brought into contact with the second conical peripheral surface 10b. With the start of the fourth weft picking, this retention member 16 is spaced from the second conical circumferential surface of the lobes to allow the predetermined length of the weft yarn Y1 to be met from the metering member 10 and clogged by the main nozzle 22. The first motor 2 »stopped at the end of the third weft picking is restarted and accelerated at the moment of stopping it, as shown by curve A3, so that at the time of the fifth weft picking, a constant speed V is reached again. the drum 10 wound the length of the weft thread for the fifth weft pick. &gt;

In this way, the motors 5, 12, the first retention members 14, 19 and the second retention members 16, 20 are controlled by the control units C1, C2 so that the fifth and subsequent weft pickings are performed as determined by the selection program.

; According to the invention, the winding speed of the weft yarns can be arbitrarily set to zero speed, constant speed, acceleration or deceleration, according to a program of choice, in a manner different from the conventional weft yarn gauging device. In addition, the operation of the weft yarn retention device can also be controlled according to the selection program in such a way that there is no need to increase the number of weft yarn retention members even when the weft yarn fed from one supply unit is clogged several times in succession. Therefore, any desired weft patterning can be arbitrarily selected by correctly assembling the ρχ-ogram selection and without the need to replace mechanical parts, except for increasing its reduction in the number of weft yarn length measuring units as a result of increasing or decreasing the number of weft yarn supply units.

CS 27G583 B6

Giant. 3 shows a modified embodiment according to which each weft thread measuring unit is associated with a sensor for sensing the number of weft threads on the drum 10. U, the measuring unit 1Λ is on the rotatable support shaft A, the back of the support member 3, or on its left 3, the gearwheel 30 is mounted, and the rotary support shaft A is driven by a first motor 5 operatively coupled to the gear 30. The aforementioned sensor for sensing the speed of the gear 30 or the number of threads Y1 on the metering member 10, for example a proximity switch 31, is disposed near the gear 30 for outputting signals to the engine control unit C1 giving functional commands to the first motor 5. a second engine .12 as will be described later. When the proximity switch 31 outputs an output signal to the control unit C1, a subsequent speed curve for the first motor 5 is calculated based on the time remaining until the predetermined weft thread length is measured, the rotation speed of the first motor 5 at the time the signal is emitted. sensor at unit C1 and at the programmed speed of the first motor 5 at the end of the weft thread measuring. The first motor 5 receives a command signal based on the result of the operation performed in the unit C1.

Referring now to Fig. 4, a typical weft insertion will now be described using the above-described embodiment provided with a wound count sensing means of wound weft threads in which the weft threads Y1, Y2 are clogged according to the weft insertion pattern so that the yarn Y1 is clogged twice. , the yarn Y2 is clogged once, the yarn Y1 is clogged four times, the yarn Y2 '' is clogged twice, and finally the yarn Y1 is clogged three times, respectively. The operation already described with reference to FIG. 2, is not described to avoid unnecessary description.

In the lower part of FIG. 4, indicating the length of the weft thread, the measured length is represented by a broken line and is represented by the product V. where t indicates the time that the moving parts of the weaving loom need to complete one revolution, and V is the predetermined speed of the motor 5 or 12, determined by the width of the fabric and the number of weft threads per unit time. The aforementioned yarn length is the yarn length Y1 or Y2, wound five times around the metering member 10. The dots on the curves indicating the rotational speeds of the first and second motors 5, 12 represent the time points of arrival of the output signals of the switch 31 to the control unit C1.

The rotation speed of the first motor 5 is programmed to equal a predetermined speed V at the time P1 when the metering is started, as well as at the time P2 when the metering is finished. In the measuring interval P1 - P2 (equal to the time interval t), the speed of the motor 5 is controlled as follows.

—O * -

At time P1, the first motor 5 is driven at a predetermined speed V as described above. This rotational speed is maintained by the command of the control unit C1 until the next output signal of the proximity switch 31 is received, i.e. the gear 30 performs one full revolution and the yarn Y1 is wound once around the metering blade 10. This time coincidence is shown in point al in FIG. 4. It is now assumed that the first motor 5 rotates at a predetermined speed V without changing the speed. At the time a1, when the proximity switch sensing signal 31 is applied, the control unit C1 calculates a subsequent speed curve for the first motor 5 to be constant and equal to V based on the time remaining until the end of the length measurement P2 or 4/5 t 4, at the actual speed V of the first motor 5 at time al and at the programmed speed of the first motor 5. at time P2, and gives the first engine a velocity command V based on the result of the operation. It is further assumed that the first motor 5 continues to rotate at speed V without changing the speed. Then, at the time a2 when the proximity switch sensing signal 31 is applied, the unit C1 calculates the subsequent speed of the first motor 5 to be constant and equal to V, based on the time remaining until the end of the length measurement P2 or 3/5 t_Qat the actual speed V of the first motor 5 at time a2 and n and the programmed speed V of the first engine 5 at time P2,

CS 27G583 B6 and gives the first motor 5 a velocity command V based on the result of the operation.

If the speed of the first motor 5 decreases from the time P1, the output signal of the proximity switch 31 is applied to the control unit C1 at a time later than the time a1 when it is _inThe signal of the proximity switch 31 is supplied to the unit C1. Therefore, at the time a1 kdv, this output signal is applied to the control unit C1, calculating this subsequent velocity curve for the first motor 5, based on the time to elapse before the metering of P2, which is less than 4/5 '. at the actual speed of the first engine 5 at the time of al? which is lower than V, and at the programmed speed V of the first motor 5 at time P2, and commands the first motor 5 to increase the speed.

Conversely, if the speed of the first motor 5 increased from the beginning of the transducer P1, the output signal of the proximity switch 31 is supplied to the control unit C1 before the time A1 of the output signal arrives. Therefore, at the time a1, when this output signal of the control unit cc is applied, this calculates a subsequent speed curve for the first motor 5 based on the time remaining until the metering time at P2 is greater than 4/5 t_Q, at the actual speed of the first motor 5 at time α1 which is greater than V, and at the programmed speed V of the first motor 5 at time P2, and commands the first motor E&gt; to reduce the speed.

Such speed control is performed each time the output signal of the proximity switch 31 is applied to the control unit C1 so that at time P2 a predetermined weft yarn length Y1 is wound on the metering member 10 and the speed of the first motor 5 sc is equal to the programmed speed V.

At the same time as the weft thread Y1, the length of which has been measured during the time period P1 to P2, becomes clogged, the first motor 5 is continuously decelerated and is stopped at the end of the third pick.

The speed of rotation of the first motor 5 in the time interval -P2 to P3 is determined so that at the beginning of the metering at time P2 it equals the speed V and is zero at the end of the metering at time P3 in Fig. to P3 (equal to 3/2 and corresponding to one and a half turns of the movable parts of the weaving loom) is performed similar to the speed control described above at times P1 to P2.

Therefore, at the time P2 when the proximity switch output signal 31 is applied to the control unit C1, the unit C1 calculates the subsequent speed curve for the first motor 5, based on the time remaining to P3 of 3/2 Οθ, based on the actual speed of the first motor 5 at time P2 and at the programmed speed of the first motor 5 at time P3, which is zero, and gives the first motor a command signal based on the result of the operation. The unit C1 performs similar speed control each time the output signal of switch 31 is received.

By the time period P2 to P3, the second pick is performed while the length of the weft yarn Y1 to be clogged in the fourth pick is wound on the metering member 10. At the end of the second pick, the second motor 12 is accelerated from standstill by the control of the control unit C1. During the measurement of the time Q1 to Q2 in Fig. 4, the second motor 12 is switched from acceleration to deceleration and is stopped at the beginning of the fourth weft pick by controlling the control unit C1.

By this time Q1 to 02, the speed control of the second motor 12 is performed by the unit C1 similar to the first motor 5, based on the output signals of the proximity switch 31 associated with the yarn length measuring unit 1B.

At the beginning of the third weft picking, the second retention member 20 associated with the second unit 1B is spaced from the second conical circumferential surface 10b and the length of the weft yarn W2 wound on the metering member 10 during the previous depositing cycle according to the weft insertion pattern is retracted by the main nozzle 23. with the metering member 10 to be clogged.

This length is equal to a predetermined length and corresponds to the height of the curve E drawn by the dashed line at the bottom of FIG. 4. During the period Q1 to Q2, the first retaining member 19 is controlled according to the weft selection program so that the weft length is wound on the drum. thread Y2 to be sewn during the eighth pick. During the period Q1 to 02, the second retaining member 16 associated with the unit 1A is brought into contact with the second conical peripheral surface 10b. At the time of initiation of the fourth pick, the second retention member 16 'is spaced from the second conical peripheral surface 10b such that the length of the weft yarn Y1 equal to a predetermined distance is retracted and clogged by the main nozzle 22 from the drum. The first motor 5, which was stopped at the end of the third pick, is accelerated at the moment of stopping so that at the beginning of the fifth pick, the specified speed V is reached. During this acceleration time of the first motor 5. the length of the weft yarn Y1 to be inserted during the fifth pick is wound on the drum.

The first and second motor 5, 12, the first retention members 14, 19 and the second retention members 16, 20 can in this way be controlled by the control units C1, C2 so that the fifth and subsequent weft pickings are performed according to a specified weft yarn selection program. In addition, since the speed of the first and second motors 5, 12 is controlled each time the output signals of the respective proximity switches 31 are fed to the control unit C1, the weft thread lengths can be accurately measured without any noticeable fluctuations. lengths.

The invention is not limited to the embodiments described above, but may include a number of modifications. For example, the retaining members 14, 16; 19, 20 may be extended and retracted by the associated electromagnets from the metering member 10. The winding tube 8 can be fixed and the metering member 10 can rotate. Three or more yarn supply units as well as three or more yarn length measuring units may be provided. In addition, only one, three or more thread retention members can be provided within the scope of the invention. The rotational speed of the motors 5, 12 can be predetermined by the control program, and the normal speed of the motors 5, 12 is compared with the programmed speed whenever the output speed control signal C1 is applied to the motor speed control unit C1. wherein the metering member 10 is rotated and the winding tube 8 is stationary.

It follows that the arrangement according to the invention allows precise control of the weft yarn winding speed on two or more drums, the length of the wound yarn and the operation of the yarn retention means according to a predetermined weft yarn selection program, allowing the weft yarn or yarn to be clogged. any desired designs without the need to replace the mechanical parts, provided that the control program is constructed accordingly. Further, in addition to the above-described control of the weft yarn winding speed and the operation of the weft yarn retention members, the weft yarn winding speed on the respective drums can be controlled whenever the output signals of the sensing means for sensing the number of weft yarn turns are output. In this case, any deviations of the engine speed from the programmed speed due to the rotational resistance or the unstable braking power can be compensated, thereby ensuring greater accuracy in measuring the length of the weft yarns.

ΗΕ Η TOVE