Weft insertion apparatus

Abstract: A weft yarn (4) is needed to be inserted into a a picking main nozzle (3) when the weft yarn (4) is broken between the picking main nozzle (3) and a yarn package during weaving operation. The present invention relates to a weft insertion apparatus capable of inserting the weft yarn (4) automatically. According to the weft insertion apparatus (1), the weft yarn (4) is flown by an air current generator (8) from a winding yarn guide (9) on a stationary drum type measuring and storing device (2) toward a yarn suction device (22), received by the yarn suction device (22), retained by a yarn conveying member (23) at the portion adjacent to the yarn suction device (22) and guided into an inlet of the picking main nozzle (3).

Description: The present invention relates to an improvement of a weft insertion apparatus for inserting a weft yarn on a measuring and storing device into a main nozzle. There have been disclosed prior art automatic weft insertion apparatus of this type in Japanese Patent Laid-open Publication Nos. 64-40638, 62-62955 (see also EP-A-0 216 220), 61-119746 (see also EP-A-0 171 057) and the like. Inasmuch as the prior art weft insertion apparatus have a weft insertion suction tube positioned over a storage drum, an insert rapier is restricted in its operation for grasping and conveying a weft yarn extended between a winding yarn guide and the suction tube, whereby an erroneous operation is liable to occur. Furthermore, inasmuch as the insert rapier moves near the measuring and storing device and moves to an inlet of the main nozzle, the amount of motion in the radial direction of the storage drum and an insertion direction is increased whereby a mechanical error is increased which results in unstable insertion opparation. It is proposed that an intermediate nozzle is provided between the main nozzle and the measuring and storing device and the weft yarn is once inserted from the winding yarn guide to the intermediate nozzle and thereafter air is jetted from the intermediate nozzle toward the inlet of the main nozzle to comlete the weft yarn inertion. In this case, inasmuch as the weft yarn is picked, in weaving operation, through the intermediate nozzle, the picking operation is liable to be unstable due to the internal resistance of the intermediate nozzle and the weft yarn insertion operation, i.e., to insert the weft yarn by air from the intermediate nozzle to the main nozzle, becomes unstable. That is, air is rebounded at the inlet of the main nozzle and is liable to generate the turbulence which needs a special arrangement of the main nozzle. However, in view of the picking operation, it is undesirable to provide the special arrangement of the main nozzle and difficult to be performed. It is therefore an object of the present invention to provide a weft insertion apparatus capable of guiding the weft yarn on the measuring and storing device to a picking main nozzle with assurance. To achieve the object of the present invention, the weft insertion apparatus of the present invention comprises an air current generator provided at the portion communicating with a winding yarn guide of the drum type measuring and storing device, a yarn suction device at the portion adjacent to the picking main nozzle, i.e., to the inlet of the main nozzle in confronting relation with an exit of the winding yarn guide located at the prescribed rotary position and a yarn conveying member for effecting reciprocal motion between the yarn suction device and the inlet of the picking main nozzle. At the time of the weft insertion operation, the air current generator generates the air current inside the winding yarn guide in the weft yarn insertion direction to thereby disperse the internal weft yarn toward the inlet of the yarn suction device. During the term, the yarn suction device generates the air current in the drawing direction at the state where the yarn suction device confronts the exit of the winding yarn guide to thereby draw a running weft yarn inside thereof. Thereafter, the yarn conveying member retains or grips the weft yarn at the portion adjacent to the yarn suction device and moves toward the main nozzle thereby guiding the weft yarn to the portion adjacent to the inlet of the main nozzle. At this state, the main nozzle generates the air current in the picking direction so as to draw the weft yarn guided by the yarn conveying member thereinto so that the main nozzle is in a picking standby state. According to the present invention as mentioned above, inasmuch as the weft yarn is guided by the air current from the winding yarn guide to the yarn suction device, a mechanical guiding member for guiding the yarn is unnecessitated to simplify the structure thereof. Furthermore, the yarn is not received by the main nozzle but received by the exclusive yarn suction device so that the yarn can be received together with air current with assurance. Still furthermore, since the yarn is mechanically guided by the yarn conveying member from the yarn suction device to the main nozzle, the yarn is inserted with assurance and without an erroneous operation. With the arrangement of the present invention set forth above, the following effects can be obtained. Firstly, inasmuch as the arrangements of the insert rapier and the yarn suction device are simplified, the weft insertion apparatus can be put into practice with ease. Secondly, inasmuch as the insert rapier is operated linearly or in the circular arc with simple repetitive operation, a complex guide mechanism is unnecessitated so that the yarn insertion can be effected with assurance. Thirdly, inasmuch as the weft yarn is guided by the air current generated by the air current generator from the winding yarn guide to the yarn suction device provided at the side of the main nozzle, the yarn insertion is effected at high speed. Fourthly, the weft yarn is not received by the main nozzle but received by the exclusive yarn suction device so that the weft yarn can be received by the exclusive yarn suction device with assurance. Fifthly, the weft yarn insertion from the yarn suction device to the main nozzle is effected by the yarn conveying member, i.e., by the insert rapier and the yarn guide with the weft yarn being held mechanically, the weft yarn can be guided toward the inlet of the main nozzle with assurance and without erroneous operation. Sixthly, since the yarn suction device and the yarn conveying member are respectively provided at the side of the main nozzle, the yarn suction device and the yarn conveying member can be utilized in common even in case of a multicolor loom. The invention is claimed in claim 1, with further embodiments in claims 2-7. The above and other objects, features and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings. Fig. 1 is a plane view of a weft insertion apparatus according to a first embodiment of the present invention; Fig. 2 is a side elevational view of the weft insertion apparatus of Fig. 1; Fig. 3 is a front elevational view of the weft insertion appartus of Fig. 1; Fig. 4 is a cross sectional view of a yarn suction device employed in the weft insertion apparatus of Fig. 1; Fig. 5 is an enlarged side elevational view of an insert rapier employed in the weft insertion apparatus of Fig. 1: Fig. 6 is an enlarged plane view of a yarn guide employed in the weft insertion apparatus of Fig. 1; Fig. 7 is a plane view of a yarn slope employed in the weft insertion apparatus of Fig. 1; Figs. 8 to 11 are front elevational views and a side view according to other embodiments of the present invention; Fig. 12 is a block diagram of a driving control circuit for a yarn guide motor; Fig. 13 is a block diagram showing an arrangement of a switching circuit; Fig. 14 is a block diagram showing a control system of cylinders; Fig. 15 is a view of an assistance in explaining yarn signals relative to solenoid valves; and Fig. 16 is a block diagram showing an arrangement of a driving control circuit for a loom motor. A weft insertion apparatus according to a first embodiment of the present invention will be described with reference to Figs. 1 to 7. Figs. 1 to 3 illustrate an arrangement of a weft insertion apparatus 1 in relation to a drum-type measuring and storing device 2 and a picking nozzle 3. There is provided a yarn guide device 50 composed of mainly guide tubes 6, 7 between the measuring and storing device 2 and yarn packages 5, 5. A weft yarn 4 is supplied from one of the yarn packages 5, 5 and travels inside the guide tubes 6, 7 and guided inside a winding yarn guide 9 of the measuring and storing device 2. A leading end of the weft yarn 4 supplied from one package 5 is connected to a tail end on the other package 5 and the weft yarn 4 is retained by two clampers 10, 10 positioned between the yarn packages 5, 5. The weft yarn 4 thus held by the two clampers 10, 10 can be cut by two electromagnetic operation cutters 11, 11. One guide tube 6 among two guide tubes 6, 7 of the yarn guide device 50 is inserted into an end of the guide tube 7 and retractably retained by a pneumatic driving cylinder 12. An air current generator 8 is provided at the inlet side of the one guide pipe 6. The other guide pipe 7 is disposed so as to cross a central axis of a storage drum 14 of the measuring and storing device 2 and connected to an inlet side of a rotary shaft portion of the winding yarn guide 9 and to a pullback nozzle 13. The pullback nozzle 13 is provided for generating air current inside the winding yarn guide 9 in the pullback direction so as to pullback the weft yarn 4 from the storage drum 14. When the weft yarn 4 remained on the measuring and storing device 2, i.e., the weft yarn 4 remained on the storage drum 14 is removed in the case that the yarn is broken between the measuring and storing device 2 and the main nozzle which result in stoppage of the loom. The weft yarn 4 on the storage drum 14 is removed by the cooperation of the pullback nozzle 13 and retracting motion of a retaining pin 18 from the circumference of the storage drum 14 and a predetermined rotary motion of the winding yarn guide 9 at low speed in the direction opposite to the winding direction. The rotary motion of the winding yarn guide 9 is controlled by a driving control circuit 98 of a motor 19 as illustrated in Fig. 12. That is, when the weft yarn 4 is removed from the drum 14, the driving control circuit 98 sets a flip-flop 134 when an operation instruction is applied to an input terminal 146 whereby a contact 152 is closed by a driver 148, a relay 150 so that the motor 19 is rotated by a driving amplifier 191 in the direction opposite to the winding direction of the weft yarn 4 at the rotating speed set by a setting unit 154. A counter 130 receives a rotary pulse signal from an encoder 57 connected to a rotary shaft of the motor 19. The driving control circuit 98 resets the flip-flop 134 when the rotary pulse signal reaches a predetermined value set by a setting unit 126 so that the rotary motion of the motor 19 stops. The rotary pulse signal from the encoder 57 is converted to a voltage by an F/V converter 192 and applied to an adding point 190 as a feedback signal. A leading end of the weft yarn 4, after it is pull back, is cut by an electoromagnetic operation cutter 15 and discharged from a discharge pipe 16 to a prescribed position. Since the pullback nozzle 13 is kept operated after the weft yarn 4 is cut off, the cut end of the weft yarn 4 from the yarn package 5 is kept held inside the pullback nozzle 13. When the weft yarn 4 now supplied from the yarn package 5 is cut between the yarn package 5 and the measuring and storing device 2, the breakage state is detected by a yarn detector 17 at the portion, e.g., of the guide tube 6 or the guide tube 7 so that the loom stops. Thereafter, a blowing nozzle 61 and the main nozzle 3 jet air under pressure so as to remove the weft yarn 4 from the storage drum 14 while a suction device in an improper weft yarn removal device 38 is operated and a retaining pin 18 is retracted from the circumference of the storage drum 14. As a result, the weft yarn 4 on the drum 14 passes the main nozzle 3 and is discharged into the improper weft yarn removal device 38. When a yarn detector 39 provided in the improper yarn removal device 38 provides a yarn nonexisting signal, a blowing nozzle 61, the main nozzle 3 and the removal device 38 respectively stop their operations. A cylinder 12 advances the guide tube 6 to thereby move the inlet side of the guide tube 6 to the portion adjacent to the weft yarn 4 positioned in the intermediate position between the two clampers 10, 10. At the same time, the air current generator 8 generates air current inside the guide tubes 6, 7 and the winding yarn guide 9 in the drawing direction. Then, the cutter 11 at the cut portion cuts the weft yarn 4 between two clampers 10, 10. Hence, a new leading end of the another yarn package 5 is drawn inside the guide pipe 6 together with air current and the weft yarn 4 from the another yarn package 5 is removed from the clamper 10 by the release operation of the clamper 10 or by a strong suction caused by air current. The weft yarn 4 is then drawn into the guide tubes 6, 7 and finally guided inside the winding yarn guide 9. The operations set forth above are sequentially effected by a controller, not shown. The drum type measuring and storing device 2 winds and measures the weft yarn 4 on the circumference of the stationary storage drum 14 by the rotary motion of the winding yarn guide 9 while the weft yarn 4 is retained by the retaining pin 18, thereafter stores the weft yarn on the storage drum 14. The winding yarn guide 9 is tubular and supported at the rotary shaft thereof in the central axis of the storage drum 14 and is driven by the motor 19. Although the retaining pin 18 is driven by a solenoid 20 to thereby enter the circumference of the storage drum 14 and retain the weft yarn 4 on the storage drum 14 when the measuring and storing operation is performed, the retaining pin 18 withdraws in the picking phase to thereby release the weft yarn 4, which is stored on the measuring and storing device 2 after subjected to the measurement, from the storage drum 14, whereby the weft yarn 4 is ready for picking. The picking main nozzle 3, when in the picking phase a solenoid valve 69 directly connected thereto is opened, draw the released weft yarn 4 into the picking fluid, thereby jetting the weft yarn 4 together with the picking fluid along the guide of a reed 21 and picking the weft yarn 4 into a shed of the warp yarn. The picking main nozzle 3 is fixed as well as the reed 21 on a reed holder 267 which is mounted on a slay sword 265. The picking main nozzle 3 performs swinging motion in synchronism with the motion of the loom. The weft insertion apparatus 1 according to the first embodiment of the present invention is composed of the air current generator 8, a yarn suction unit 22, a yarn conveying member 23 and a cutter 36. The air current generator 8 is provided not only at the guide tube 6 but also at the guide tube 7 or the winding yarn guide 9 for generating air current inside the winding yarn guide 9 in the yarn insertion direction of the weft yarn 4. The yarn suction device 22 confronts the outlet of the winding yarn guide 9 when stopped and attached to the side, e.g., the portion over the picking main nozzle 3, via supporting shafts 71, 73 on a frame 24 and composed of a suction nozzle 25, a trumpet-shaped guide body 26 provided at the suction side of the suction nozzle 25 and a discharge pipe 27 provided at the discharge side of the suction nozzle 25 as illustrated in Figs. 1 and 4. A tip end of the discharge pipe 27 is positioned at the portion adjacent to the improper yarn inlet portion of the improper yarn removal device 38 mounted on the frame 24 via a stay 75. The yarn conveying member 23 retains the weft yarn 4 extended between the winding yarn guide 9 and the yarn suction device 22 and guides the weft yarn 4 from the yarn suction device 22 to the inlet side of the main nozzle 3. The yarn conveying member 23 comprises an insert rapier 28 as illustrated in Fig. 5, a forked shaped yarn guide 29 attached to the tip end of the insert rapier as illustrated in Fig. 6, a supporting body 77 for rotatively supporting the insert rapier 28 and the yarn guide 29 via an arm 30, a fulcrum shaft 32 and a cylinder 31. The arm 30 is rotatively suppoted by the supporting body 77 which is fixed to the supporting shaft 71 by the fulcrum shaft 32 at the rear end thereof. The arm 30 holds the insert rapier 28 and the yarn guide 29 and is connected to a piston rod 33 of the cylinder 31 by a pin 34 at the rear end thereof via the fulcrum shaft 32. The cylinder 31 is rotatively supported by a supporting shaft 35 to the frame 24 at the rear end thereof. Hence, the yarn conveying member 23 is movable by rotation thereof from the front side of the yarn suction device 22 to the inlet side of the main nozzle 3. There is attached the solenoid operation cutter 36 as illustrated in Fig. 2 to the supporting shaft 73 by a bracket 37. The solenoid operation cutter 36 can be attached to the portion adjacent to a side of the yarn suction device 22 as illustrated in Fig. 4. There is provided a yarn slope 40 at the portion adjacent to the insert rapier 28 as illustrated in Fig. 7 so that the weft yarn 4 extended from the cutter 34 to the main nozzle 3 is not entangled with the weft yarn 4 from the storage drum when the weft yarn is cut between the main nozzle 3 and the yarn suction device 22. In the initial yarn insertion operation or the yarn insertion operation after breakage of the weft yarn 4, the winding yarn guide 9 is positioned always in confronting relation with the yarn suction device 2 so as to be ready for the weft insertion operation. That is, the controller (not shown) provides an instruction signal to an input terminal 162 of the driving control circuit 98 after the loom is stopped. At this time, the winding yarn guide 9 has stopped already at an arbitrary position simultaneously with the stoppage of the loom. A flip-flop 163, upon reception of the instruction signal, is set and a contact 166 is closed by a driver 164, a relay 165 so that the motor 19 is rotated at the speed set by a setting unit 167. A converter 168 receives a pulse signal from the encorder 57 and converts the pulse signal into a rotary angle signal which is provided to the comparator 169. The comparator 169 provides a signal to the flip-flop 163 when an output of the converter 168 coincides with a predetermind rotary angle set by a setting unit 170 whereby the flip-flop 163 is reset to stop the rotary motion of the motor 19. The yarn conveying member 23 is kept stopped at a standby position by the cylinder 31. When the weft yarn is broken, the controller, not shown, processes as mentioned earlier and thereafter the air current generator 8 generates air current inside the winding yarn guide 9 in the yarn insertion direction so that the weft yarn 4 inside the guide tubes 6, 7 is inserted into the winding yarn guide 9 and is jetted from the tip end thereof so as to run into the yarn suction device 22. Whereupon, the yarn suction device 22 generates air current by the suction nozzle 25 into the yarn insertion direction at the picking operation. Furthermore, the suction unit of the improper yarn removal device 38 starts the suction operation. Accordingly, the weft yarn 4 flies out of the exit of the tip end of the winding yarn guide 9 and travels toward the yarn suction device 22 and is introduced into the inside of the discharge pipe 27 by the air current in the direction of the yarn suction device 22 via the inside of the suction nozzle 25. The existence of the weft yarn 4 inside the discharge pipe 27 is detected by the yarn detector 39 at the inside of the improper yarn removal device 38 or the inside of the discharge pipe 27. After detection of the weft yarn 24, the air current generator 8 stops and the cylinder 31 actuates so that the insert rapier 28, the yarn guide 29 and the yarn slope 40 of the yarn conveying member 23 are respectively rotated about the fulcrum shaft 32 so that the insert rapier 28 is moved from the standby position to the inlet side of the main nozzle 3. When the yarn guide 29 is moved to the posision on the axial line of the suction nozzle 25, the weft yarn 4 extended from the winding yarn guide 9 to the suction nozzle 25 is positioned inside a guide introduction opening 79 of the yarn guide 29 and thereafter guided to an introduction groove 81 defined at the center of the yarn guide 29 with the movement of the yarn guide 29. At this time, the weft yarn 4 is retained by the tip end portion of the insert rapier 28 disposed in parallel with the introduction groove 81 at the same position and the retained weft yarn 4 is moved to the inlet of the main nozzle 3. At this time, the weft yarn 4 is pulled back from the discharge pipe 27 and guided toward the inlet side of the main nozzle 3. At this state, the retaining pin 18 of the measuring and storing device 2 advances toward the circumference of the storage drum 14, thereafter the winding yarn guide 9 is rotated at the prescribed amount to thereby wind the weft yarn 4 preliminarily on the storage drum for the necessary amount. That is, when the insert rapier 28 reaches the inlet of the main nozzle 3, the instruction signal is provided from the controller to an input terminal 136 of the driving control circuit 98 so that a flip-flop 132 is set and a contact 142 is closed by a driver 138 and a relay 140 whereby the motor 19 is rotated at the speed set by a setting unit 144. When the motor 19 is rotated for the amount prescribed by a setting unit 171, a counter 128 resets the flip-flop 132 so that the motor 19 is stopped. Thereafter, when the air current is generated inside the main nozzle 3 by the actuation of the solenoid valve 69 in the picking direction so that the weft yarn 4 guided by the insert rapier 28 and the yarn guide 29 is drawn inside thereof. Thereafter, the cutter 36 is actuated to cut the weft yarn 4 between the yarn suction 22 and the yarn conveying member 23. After the weft yarn 4 is cut, the weft yarn 4 extended from the winding yarn guide 9 to the main nozzle 3 is not entangled with the cut end of itself due to the existence of the yarn slope 40. So, the cut end of the weft yarn 4 is easily guided to the inside of the main nozzle 3 and inserted into the main nozzle 3. The weft yarn 4 inside the discharge pipe 27 is drawn into the improper yarn removal device 38 by the air current and discharged to the prescribed position. At the same time, the retaining pin 18 is retracted from the circumference of the storage drum 18 and when a release detecter 83 provided at the portion adjacent to the storage drum 14 detects the number of windings, e.g., two windings of the weft yarn released from the storage drum 14, the retaining pin 18 advances to the circumference of the storage drum 14. The weft yarn 4 inserted into the main nozzle 3 by the already actuated blowing nozzle 61 is guided into the suction opening of the improper yarn removal device 38. When the yarn detecter 39 detects the weft yarn 4, a cutter 263 is actuted to cut the weft yarn 4 at the tip end of the main nozzle 3. Thereafter, the yarn suction device 22, the suction unit of the improper yarn removal device 38 and the main nozzle 3 are respectively stopped and the insert rapier 28 returns to the standby position. The preliminary winding operation can be effected when the weft yarn 4 has been extended between the winding yarn guide 9 and the yarn suction device 22. In this case, the insert rapier 28 retains the weft yarn 4 extended between the retaining pin 18 and the yarn suction device 22. The weft yarn 4 may be gripped and conveyed by a yarn gripping device provided at the tip end of the insert rapier 28. A weft insertion apparatus according to a second embodiment of the present invention will be described with reference to Fig. 8. In the second embodiment employing a two-color loom, in order to utilize a common yarn suction device 22, an axial line 51 of the each storage drum 14 (a rotary center line of the each winding yarn guide 9) respectively passes through the corresponding inlet of the main nozzle 3 of the two-color loom and a center line 53 of the exit of the each winding yarn guide 9 is defined to pass through a common point adjacent to the portion over the main nozzle 3 and the yarn suction device 22 is provided at the common point. The inlets of the main nozzle 3 are disposed in parallel with each other and spaced in the same interval from the swing motion center of the reed holder 67. In this case, the output of a driving control circuit 98 of the motor 19, as illustrated Fig. 13, is connected to each motor 19a, 19b via a swiching circuit 100 so that the driving control 98 is commonly utilized to the motor 19a, 19b. That is, when the instruction signal is provided by the controller, a corresponding flip-flop 104 or 105 is set via AND gates 102 or 103 which has received the weft yarn selection signal from a weft yarn selection device 101 so that a corresponding contact 108a or 109b is closed by an actuated driver 106 or 107 and an actuated relay 108 or 109 whereby the corresponding motor 19a or 19b for the prescribed winding yarn guides 9, 9 is ready to be rotated. Stoppage position of the each winding yarn guide 9, 9 is previously set in the setting unit 170 and the corresponding set value is read out therefrom on the basis of the weft insertion selection signal. The driving control circuit 98 can be provided per each of the motors 19a, 19b so that the driving control circuit 98 is actuated on the basis of the weft yarn selection signal provided by the weft yarn selection device 101. According to the present invention, the exits of each winding yarn guide 9 are defined to have cross angles between the center lines 55 of the winding yarn guide 9 and the center lines 53 of the exits thereof are set to be α . Accordingly, the cross point is positioned midway of the distance connecting centers of the storage drums 14, 14 and at the surface vertical to a straight line connected to the centers of the storage drums 14, 14. With such an arrangement, at the weft insertion operation, the corresonding winding yarn guide 9 stops at the prescribed rotary position so that the weft yarn 4 from the winding yarn guide 9 is supplied to the common yarn suction device 22 which results in that the yarn suction device 22 is commonly utilized for the weft yarns 4 in the two-color loom. A weft insertion apparatus according to a third embodiment of the present invention will be described with reference to Fig. 9. The third embodiment relates to the weft insertion apparatus employing a four-color loom in which each axial shaft line 51, .. 51 of the each storage drum 14, .. 14 (a rotary center line of the each winding yarn guide 9, ... 9) respectively passes through the corresponding inlet of the main nozzle 3 while the center line 53 of the exit of the each winding yarn guide 9, .. 9 is respectively defined to pass through a common point adjacent to the portion over the main nozzle 3 and the yarn suction device 22 is provided at the common point. In upper measuring and storing devices 2, 2 according to the third edmbodiment, there are provided the winding yarn guides 9, .. 9 each having the exit so as to form the crossing angle β between center lines 55 of the winding yarn guides 9 and the center lines 53 of the exits thereof. In lower measuring and storing devices 2, 2 there are provided the winding yarn guides 9, .. 9 each having the exit so as to form the cross angle γ. The relationship between the crose angle β and the cross angle γ is expressed as β<γ . The driving control circuit 98 of the motor 19 is substantially same as that of the second embodiments except that the number of the motor 19 is increased. When the multicolor loom, e.g., a four-color loom is employed, the insert rapier 28 shall be moved to the corresponding inlet of the main nozzle 3 at the weft insertion operation. Hence, the yarn conveying member 23 is structured to be movable by a dividing mechanism 41 capable of dividing into X and Y directions which are common to four main nozzles 3a, 3b, 3c and 3d as illustrated in Fig. 10. The dividing mechanism 41 comprises a rotary actuator 43 capable of rotatively supporting the insert rapier 28, a slider 99 capable of vetically movably supporting the rotary actuator 43 together with the insert rapier 28 by a pneumatic driving double mechanism cylinder 87 and a base 110 horizontally movably supporting the rotary actuator 43 together with the insert rapier 28 by a pneumatic double mechanism 85. Each of the cylinders 85, 87 is connected, as illustrated in Fig. 14, to solenoid valves 89, 91; 93, 95. There is provided a switching circuit 97 at the solenoid portions of the solenoid valves 89, 91; 93, 95. The switching circuit 97 is connected to the weft yarn selection device 101 at the input side thereof in which active or inactive signals a, b, c, d are provided to each of the solenoid valves 89, 91; 93, 95 in response to the selected kind of weft yarn as illustrated in Fig. 15. Consequently, the dividing mechanism 41 moves toward the X-axis (horizontal) direction or the Y-axis (vertical) direction for thereby allowing the tip end of the insert rapier 28 to move to any of the inlet side of the corresponding main nozzles 3a, 3b, 3c, 3d. Although the weft insertion apparatus according to the third embodiment can be moved from the yarn suction device 22 to the main nozzle 3 by the rotary motion of the yarn conveying member 23, the yarn conveying member 23 can be structured to perform the linear motion by a cylinder 44 as illustrated in Fig. 11. That is, a piston rod 45 of the cylinder 44 at the retraction position advances when the weft yarn is guided so that the weft yarn 4 extended from the winding yarn guide 9 to the yarn suction device 22 is retained by the insert rapier 28 and guided to the inlet of the main nozzle 3. In case of the weft yarn insertion operation in the multicolor loom, the cylinder 44 is positioned as to mate with the corresponding main nozzle 3 as the rotary actuator 43 is so that the weft yarn 4 is guided to each inlet side of the main nozzle 3. The stoppage position of the main nozzle 3 to which the weft yarn is inserted may be always constant by switching the stoppage angle of the loom corresponding to the selected kind of weft yarn instead of moving the position of the insert rapier 28 in the X-axis direction. The stoppage angle of a drive motor 54 of the loom is controlled by a driving control circuit 52 connected to the weft yarn selection device 101 as illustrated in Fig. 16. Two stoppage angles of a loom are set in a setting unit 58 in response to the kind of yarns a, b and b, c. When the instruction signal is provided from the controller, not shown, to an input terminal 60 after the loom is stopped, a flip-flop 62 is set and a contact 64 of the relay 63 to be driven by the driver 65 is closed so that the driving motor 54 is rotated by the driving circuit 67 at the prescribed speed. Whereupon, a selection instruction unit 66 reads the set value corresponding to the weft yarn selection signal from the setting unit 58 and provides the set value thus read to a comparator 68. The comparator 68 resets the flip-flop 62 when the output of a converter 70 coincides with the set value to thereby stop the loom at the prescribed rotary position. In this case, the cylinder 87 alone serves as the driving member for moving the insert rapier 28. The switching circuit 97 controls the solenoid valves 93 and 95 so as to advance or retract the cylinder 87 in response to the selected kind of yarns a, b and the kind of yarns c, d. The rotary motion of the driving motor 54 is detected by an encoder 59 and the detected rotary motion is fedback to the adding point 155 by a F/V converter 56. With such an arrangement, the insert rapier 28 may be moved in the Y-axis direction only. In case that all inlets of main nozzle of the multicolor loom can be disposed on a circular arc around the swing motion axis of the slay sword 265, the common suction device 22, the yarn conveying member without the dividing mechanism and the stoppage angle controller can be employed. Although the invention has been described in its preferred form with a certain degree of paticularity, it is to be understood that many variations and changes are possible in the invention without departing from the scope thereof as claimed.

Claims: A weft insertion apparatus (1) comprising: an air current generator (8) for generating air current through a winding yarn guide (9) of a measuring and storing device (2) in the picking direction; a yarn suction device (22) disposed at a position other than the axial shaft line of a picking main nozzle (3) and at the side of the picking main nozzle (3) thus confronting an exit of the winding yarn guide (9) which is positioned in a prescribed rotary position; and a yarn conveying member (23) for grasping a weft yarn (4) extended between the measuring and storing device (2) and the yarn suction device (22) and guiding the weft yarn (4) thus grasped to an inlet of the main nozzle (3). A weft insertion apparatus (1) according to claim 1, and further comprising: a cutter (36) for cutting the weft yarn (4) between the yarn suction device (22) and the yarn conveying member (23). A weft insertion apparatus (1) according to Claim 2, wherein rotary center lines of a plurality of winding yarn guides (9) coincide with centers of the inlets of the picking main nozzle (3) of a multicolor loom while exits of the plurality of winding yarn guides (9) are directed to a common yarn suction device (22) at the prescribed rotary position. A weft insertion apparatus (1) in a multicolor loom having a plurality of measuring and storing devices (2) each provided with the winding yarn guide (9) and a plurality of main nozzles (3) disposed in parallel with each other according to Claim 1 or 2 characterized in that the yarn conveying member (23) is supported by a dividing mechanism (41) which is movable to a prescribed position on the basis of an instruction from a weft yarn selection device (101). A weft insertion apparatus (1) according to Claim 3, wherein inlets of two main nozzles (3) are disposed in parallel with each other and spaced in the same interval from the swing motion center of a reed holder (267), the inlets of the main nozzles (3) to which the weft yarn (4) is inserted are positioned to prescribed positions on the basis of the instruction from a weft yarn selection device (101). A weft insertion apparatus (1) according to Claims 1, 2, 3, 4 or 5, wherein the yarn conveying member (23) comprises a rotatable insert rapier (28) and a forked yarn guide (29) attached to a tip end of the insert rapier(28). A weft insertion apparatus (1) according to Claims 1, 2, 3, 4 or 5, wherein the yarn conveying member (23) comprises the linear insert rapier (28) which is attached to a tip end of a piston rod (33) of the cylinder (31).

Inventors: TAKEHANA TATSUO, TAKEHANA, TATSUO
Applicants: TSUDAKOMA IND CO LTD, TSUDAKOMA CORPORATION
Application year: 1990
Main classification: D03D47
IPC codes: D03D47