JP6380434B2 - Weft detection method and weft detection device in jet loom - Google Patents

Description

  The present invention relates to a weft detection method and a weft detection device in a jet loom, and more particularly to a weft detection method and a weft detection device for detecting a weft arrival timing.

  In the jet loom, it is important to achieve a good weft insertion state in which the weft reaches a predetermined weft insertion end position at a predetermined timing in order to weave a high-quality woven fabric. There is a method in which the first time when the detection signal level obtained from the weft detector exceeds the set threshold value within a predetermined period during one rotation of the machine base is the weft arrival timing. However, the signal output from the weft detector may be not only the weft detection signal but also the fluff detection signal or noise signal, and the fluff detection signal or noise signal is output prior to the weft detection signal within the predetermined period. In this case, the detected weft arrival timing may be significantly different from the actual weft arrival timing.

  Conventionally, there has been proposed a weft insertion control device in a jet loom that can avoid a decrease in measurement accuracy of the weft arrival timing even when there is a fluff detection signal or a noise signal (see Patent Document 1). The weft insertion control device of Patent Document 1 counts the photoelectric weft detector that detects a weft reaching a predetermined weft insertion position, the number of detection pulse signals input from the weft detector, and the detection pulse signal. It comprises a weft presence / absence determining means for measuring input timing. Then, when the number of detection pulse signals input within a predetermined period during one rotation of the machine base reaches a preset number (set number), it is determined as the weft arrival timing.

  The signal due to fluff or noise tends to be generated relatively constantly for each rotation of the machine base, and the set number can be grasped by measuring the signal generation due to fluff or noise before the original weaving stage. The In the apparatus of Patent Document 1, when the number of pulse signals generated due to fluff or noise is (N-1) before the weft arrival signal generation, the signal generation timing due to the weft arrival is when the Nth pulse signal is detected. For example, when the number of pulse signals generated due to fluff or noise is 1, as shown in FIG. 7A, the pulse signal E2 generated before the weft arrival timing is not determined as the weft arrival signal, The leading pulse signal E1 of the pulse train E generated after the signal E2 is determined as a pulse having an accurate weft arrival timing. If the number of pulse signals generated due to fluff or noise is two, as shown in FIG. 7B, the two pulse signals E2 generated before the weft arrival timing are not determined as the weft arrival signals. In addition, the leading pulse signal E1 of the pulse train E generated after the two pulse signals E2 is determined as a pulse having an accurate weft arrival timing.

JP-A-4-24245

  In the apparatus of Patent Document 1, when the amount of fluff is large and a large amount of fluff signals are included, the actual weft arrival timing may be erroneously recognized. When controlling the weft arrival timing by pressure or the like, there is a possibility of causing a weft error by erroneously determining that the weft arrival is too early and lowering the main air pressure. Further, when the amount of fluff is smaller than the set number, a timing later than the original weft arrival is recognized as the weft arrival timing.

  The present invention has been made in view of the above problems, and the object thereof is a weft detection method in a jet loom capable of detecting accurate weft arrival timing without being affected by the amount of fluff, and It is to provide a weft detection device.

  The weft detection method in the jet loom that solves the above problem is a weft detection method in the jet loom that detects the weft arrival angle by the output pulse of the photoelectric weft detector that detects the weft. If the pulse generation angle sequence of the output pulse output from the photoelectric weft detector has a pulse generation angle smaller than the average value of the weft arrival timing, the pulse generation angle with the smallest difference from the average value is assumed. The weft arrival timing, the difference between the provisional weft arrival timing and the immediately preceding pulse generation angle is compared with the first comparison value, and if the difference is equal to or greater than the first comparison value, the provisional weft arrival timing is defined as the weft arrival timing. If the difference is less than the first comparison value, the pulse generation angle immediately before the provisional weft arrival timing is set as a new provisional weft arrival timing, and the difference between the new provisional weft arrival timing and the immediately preceding pulse generation angle is the first generation value. If the difference is greater than or equal to the first comparison value and the new provisional weft arrival timing is set to the weft arrival timing, Whether the difference between the arrival timing and the pulse generating angle immediately before is equal to or greater than the first comparative value, or said repeated until temporary weft arrival timing is the smallest pulse generating angle among the pulse generating angle train.

  In addition, when there is no pulse generation angle smaller than the average value in the pulse generation angle sequence, a pulse generation angle that is larger than the average value and has the smallest difference from the average value is set as the temporary weft arrival timing, The difference between the weft arrival timing and the pulse generation angle immediately thereafter is compared with the second comparison value. If the difference is less than the second comparison value, the temporary weft arrival timing is set as the weft arrival timing, and the difference is the second comparison value. If the value is greater than or equal to the value, the pulse generation angle immediately after the provisional weft arrival timing is set as a new provisional weft arrival timing, and the difference between the new provisional weft arrival timing and the pulse generation angle immediately thereafter is compared with the second comparison value. If the difference is less than the second comparison value, the procedure for setting the new provisional weft arrival timing as the weft arrival timing is referred to as the new provisional weft arrival timing and the immediately following pulse. The difference between the generation angle is repeated until the one second becomes less than the comparison value, or the temporary weft arrival timing becomes the largest pulse generating angle among the pulse generating angle train.

  According to this configuration, when the pulse generation angle sequence has a pulse generation angle smaller than the average value of the weft arrival timing, the pulse generation angle having the smallest difference from the average value is set as the temporary weft arrival timing, The difference from the immediately preceding pulse generation angle is compared with the first comparison value. If the difference is greater than or equal to the first comparison value, the provisional weft arrival timing is determined as the weft arrival timing. If the difference is less than the first comparison value, the pulse generation angle immediately before the weft arrival timing is set as a new provisional weft arrival timing, and the difference between the new provisional weft arrival timing and the pulse generation angle immediately before is determined as the first comparison value. If the difference is equal to or greater than the first comparison value, the procedure for setting the new provisional weft arrival timing as the weft arrival timing is the difference between the new provisional weft arrival timing and the pulse generation angle immediately before the first comparison value. The weft arrival timing is detected by repeating until the temporary weft arrival timing reaches the minimum value or the smallest pulse generation angle in the pulse generation angle sequence.

  Further, when there is no pulse generation angle smaller than the average value in the pulse generation angle sequence, the pulse generation angle that is larger than the average value and has the smallest difference from the average value is set as the temporary weft arrival timing, The difference from the immediately following pulse generation angle is compared with the second comparison value. If the difference is less than the second comparison value, the provisional weft arrival timing is set as the weft arrival timing. If the difference is equal to or greater than the second comparison value, the pulse generation angle immediately after the provisional weft arrival timing is set as a new provisional weft arrival timing, and the difference between the new provisional weft arrival timing and the pulse generation angle immediately thereafter is the second comparison value. If the difference is less than the second comparison value, the procedure for setting the new provisional weft arrival timing as the weft arrival timing is the difference between the new provisional weft arrival timing and the pulse generation angle immediately thereafter. The weft arrival timing is detected by repeating until the provisional weft arrival timing becomes the largest pulse generation angle in the pulse generation angle sequence or less than the comparison value. Therefore, it is possible to detect the accurate weft arrival timing without being affected by the amount of fluff.

  A weft detection device in a jet loom that solves the above problem is a weft detection device in a jet loom that detects a weft arrival angle by an output pulse of a photoelectric weft detector that detects a weft. And pulse generation angle applying means for applying a pulse generation angle to the pulse signal input from the photoelectric weft detector, and pulse generation for generating a pulse generation angle sequence based on the pulse generation angle of each input pulse signal An angle train creation means, a pulse angle train storage means for storing the pulse generation angle train for each pick, and an average weft arrival timing calculation means are provided. In addition, when the pulse generation angle sequence stored in the pulse angle sequence storage means has a pulse generation angle smaller than the average value of the weft arrival timing, the pulse generation angle having the smallest difference from the average value is set to the temporary weft arrival time. Comparing the difference between the first provisional weft arrival timing setting means as the timing, the provisional weft arrival timing set by the first provisional weft arrival timing setting means and the pulse generation angle immediately before the first comparison weft, If the difference is greater than or equal to the first comparison value, the provisional weft arrival timing is taken as the weft arrival timing. If the difference is less than the first comparison value, the pulse generation angle immediately before the provisional weft arrival timing is taken as the new provisional weft arrival timing. The difference between the new provisional weft arrival timing and the immediately preceding pulse generation angle is compared with the first comparison value, and the difference is not less than the first comparison value. According to the procedure of setting the new temporary weft arrival timing as the weft arrival timing, the difference between the new temporary weft arrival timing and the immediately preceding pulse generation angle is equal to or greater than the first comparison value, or the temporary weft arrival timing is First weft arrival timing determination means that repeats until the smallest pulse generation angle in the pulse generation angle row is reached.

  Further, when there is no pulse generation angle smaller than the average value in the pulse generation angle sequence, a pulse generation angle that is larger than the average value and has the smallest difference from the average value is set as the temporary weft arrival timing. The difference between the provisional weft arrival timing setting means and the provisional weft arrival timing set by the second provisional weft arrival timing setting means and the pulse generation angle immediately thereafter is compared with a second comparison value, and the difference is the second comparison value. If the difference is less than the comparison value, the temporary weft arrival timing is set as the weft arrival timing. If the difference is equal to or greater than the second comparison value, the pulse generation angle immediately after the temporary weft arrival timing is set as the new temporary weft arrival timing. The difference between the arrival timing and the pulse generation angle immediately thereafter is compared with the second comparison value. If the difference is less than the second comparison value, the new temporary weft arrival tie The difference between the new provisional weft arrival timing and the immediately following pulse generation angle is less than the second comparison value, or the provisional weft arrival timing is determined in the pulse generation angle sequence. Second weft arrival timing determination means that repeats until the largest pulse generation angle is obtained.

According to this configuration, the weft detection method can be implemented. Therefore, it is possible to detect the accurate weft arrival timing without being affected by the amount of fluff.
A setting unit that sets the first comparison value and the second comparison value may be provided. As the first comparison value and the second comparison value, preset values may be used. However, if a setting unit is provided, the first comparison value and the second comparison value that are more suitable for the weaving conditions are used. Can be set.

  According to the present invention, accurate weft arrival timing can be detected without being affected by the amount of fluff.

The schematic block diagram of a weft insertion apparatus. The schematic diagram which shows a setting screen. (A)-(c) is a schematic diagram explaining an effect | action. The flowchart explaining an effect | action. The flowchart explaining an effect | action. The figure which shows the pulse generation angle of each pick. (A), (b) is a schematic diagram explaining a prior art.

Hereinafter, an embodiment in which the present invention is embodied in an air jet loom will be described with reference to FIGS.
As shown in FIG. 1, a weft insertion device 10 of an air jet loom includes a weft storage device 11, a main nozzle 12 for weft insertion, a tandem nozzle 13 disposed upstream of the main nozzle 12, and a main nozzle. 12, a plurality of weft insertion sub-nozzle groups 14 </ b> A to 14 </ b> F disposed on the downstream side of 12, and a flange 15. The eaves 15 are formed by arranging a plurality of eaves having guide recesses in the weft insertion direction. The tandem nozzle 13 includes an ABS (automatic weft braking device) 16. The sub-nozzle groups 14A to 14F have a configuration in which a plurality of (four in this embodiment) sub-nozzles 14 are collectively arranged as one group.

  The weft storage device 11 is configured to wind and store the weft Y supplied from the weft cheese 17 as a yarn supplying section around a length measuring drum 19. The weft storage device 11 has a locking pin 20 a that is driven by an electromagnetic solenoid 20 and can be attached to and detached from the length measuring drum 19. The weft Y wound around and stored on the length measuring drum 19 is controlled to be pulled out from the length measuring drum 19 by engagement / disengagement between the locking pin 20a and the length measuring drum 19. The measuring drum 19 includes a photoelectric balloon sensor 21 that detects the balloon of the weft Y drawn from the measuring drum 19. The balloon sensor 21 detects a weft Y balloon when wefts are inserted.

  The air supply source 22 is connected to the main tank 25 via a pipe 23 and a regulator 24. The main tank 25 is connected to the main nozzle 12 via a pipe 23 and a main valve 26, and is connected to the tandem nozzle 13 via a pipe 23 and a tandem valve 27. The air supply source 22 is connected to a sub tank 29 via a pipe 23 and a regulator 28. The main valve 26 and the tandem valve 27 are controlled by the control device C, and the injection timing of the compressed air from the main nozzle 12 and the tandem nozzle 13 is controlled. The air supply source 22 is configured by, for example, an air compressor.

  The sub tank 29 includes a plurality of sub valves 30, and each sub valve 30 is connected to a plurality of sub nozzle groups 14 </ b> A to 14 </ b> F by a pipe 23. When each sub valve 30 is opened, compressed air is simultaneously injected from the four sub nozzles 14 of the corresponding sub nozzle groups 14A to 14F. Each sub-valve 30 is controlled by the control device C, and is controlled to open and close like a relay at a predetermined timing during weft insertion, so that compressed air is relay-injected from the sub-nozzle groups 14A to 14F.

  A weft feeler 31 as a photoelectric weft detector for detecting the weft Y is provided on the side opposite to the main nozzle of the reed 15. The weft feeler 31 detects the end of the weft Y at the end of the weft insertion of one pick. When the weft feeler 31 detects the weft Y and the fluff, it outputs a pulse signal.

  The control device C includes a CPU 35 and a memory 36. The control device C controls the pressure of the main tank 25 via the regulator 24 and controls the pressure of the sub tank 29 via the regulator 28. The control device C controls the injection timing of the compressed air from the main nozzle 12 and the tandem nozzle 13 by opening / closing control of the main valve 26 and the tandem valve 27. The control device C controls relay injection of the sub nozzle groups 14 </ b> A to 14 </ b> F by opening / closing control of the sub valve 30.

  The control device C constituting the weft arrival timing detection device receives the output pulse signal output from the weft feeler 31 when the weft feeler 31 detects the weft, and stores the input timing of the output pulse signal as the machine base angle. More specifically, the CPU 35 gives a machine angle at the time of pulse generation to each pulse input in the weft detection range as a pulse generation angle and creates a pulse generation angle sequence. That is, the CPU 35 constitutes a pulse generation angle applying unit and a pulse generation angle sequence creating unit. The pulse generation angle sequence created by the CPU 35 is stored in the memory 36. That is, the memory 36 constitutes a pulse angle sequence storage unit. Further, the CPU 35 calculates the weft arrival timing TW from the pulse generation angle sequence and also calculates the average value of the weft arrival timing TW to constitute an average weft arrival timing calculation means.

That is, the weft arrival timing detection device includes a pulse generation angle applying unit, a pulse generation angle sequence creating unit, a pulse angle sequence storage unit, and an average weft arrival timing calculation unit.
When the pulse generation angle sequence stored in the memory (pulse angle sequence storage means) 36 has a pulse generation angle smaller than the average value of the weft arrival timing, the CPU 35 temporarily sets the pulse generation angle having the smallest difference from the average value. It functions as first temporary weft arrival timing setting means for setting the weft arrival timing (temporary TW).

  Further, the CPU 35 compares the difference between the provisional weft arrival timing set by the first provisional weft arrival timing setting means and the pulse generation angle immediately before it with the first comparison value (Tfwd), and the difference is the first comparison value. If the difference is less than the first comparison value (Tfwd), the pulse generation angle immediately before the provisional weft arrival timing is set as a new provisional weft arrival timing. The difference between the arrival timing and the immediately preceding pulse generation angle is compared with the first comparison value (Tfwd), and if the difference is greater than or equal to the first comparison value (Tfwd), the procedure for setting the new provisional weft arrival timing as the weft arrival timing Whether the difference between the new provisional weft arrival timing and the pulse generation angle immediately before it is equal to or greater than the first comparison value (Tfwd), or the provisional weft arrival timing is in the pulse generation angle sequence Functions as the first weft arrival timing determining means for repeated until the largest pulse generation angle.

  Further, when there is no pulse generation angle smaller than the average value in the pulse generation angle row, the CPU 35 sets the second temporary provisional yarn arrival timing as a temporary generation yarn arrival timing that is greater than the average value and has the smallest difference from the average value. It functions as a weft arrival timing setting means.

  Further, the CPU 35 compares the difference between the provisional weft arrival timing set by the second provisional weft arrival timing setting means and the pulse generation angle immediately thereafter with the second comparison value (Trea), and the difference is the second comparison value. If the difference (Trea) is less than the value (Trea), the weft arrival timing is set as the weft arrival timing, and if the difference is equal to or greater than the second comparison value (Trea), the pulse generation angle immediately after the temporary weft arrival timing is set as the new temporary weft arrival timing. A procedure in which the difference between the weft arrival timing and the pulse generation angle immediately thereafter is compared with the second comparison value (Trea), and if the difference is less than the second comparison value (Trea), the new provisional weft arrival timing is set as the weft arrival timing. The difference between the new provisional weft arrival timing and the pulse generation angle immediately thereafter is less than the second comparison value (Trea), or the provisional weft arrival timing is not in the pulse generation angle sequence. In functions as the second weft arrival timing determining means for repeated until the largest pulse generation angle.

  That is, the control device C that constitutes the weft arrival timing detection device includes first temporary weft arrival timing setting means, first weft arrival timing determination means, second temporary weft arrival timing setting means, and second weft arrival timing determination means. .

  A function panel 40 as an input / output device is connected to the control device C. The function panel 40 includes a display screen 41 and input keys (not shown). The display screen 41 includes a setting screen 42 (shown in FIG. 2).

  As shown in FIG. 2, the setting screen 42 includes a weft detection range setting unit 44, a first comparison value setting unit 45, a second comparison value setting unit 46, and a yarn detection pulse number setting unit 47. The weft detection range setting unit 44 sets the weft detection range when the control device C detects (calculates) the weft arrival timing, the first comparison value setting unit 45 sets the first comparison value (Tfwd), and the second The comparison value setting unit 46 sets the second comparison value (Trea), and the yarn detection pulse number setting unit 47 sets the minimum pulse number for determining that the weft Y exists in the weft detection range. In the example of FIG. 2, the minimum machine base angle of the weft detection range is 220 ° and the maximum machine base angle is 310 °.

Next, the operation of the apparatus configured as described above will be described.
First, the weft detection range, the first comparison value Tfwd, the second comparison value Trea, and the number of yarn detection pulses are set. As the values of the weft detection range, the first comparison value Tfwd, the second comparison value Trea, and the number of yarn detection pulses, values entered by the operator in a state where the setting screen 42 is displayed on the display screen 41 of the function panel 40 are used. The In this embodiment, for example, the values shown in FIG. 2 are set. That is, the first comparison value Tfwd and the second comparison value Trea are both 5 °. Note that the first comparison value Tfwd and the second comparison value Trea are measured in advance by operating the loom before the original weaving stage. In this state, when the operator operates a weft arrival timing detection start switch (not shown), the weft arrival timing detection operation by the control device C is started.

The control device C detects the weft arrival timing according to the flowcharts of FIGS.
First, in step S1, the controller C receives a pulse generation angle of a pulse signal within a preset machine angle range (220 ° to 310 °). Then, a pulse generation angle sequence is created based on the pulse generation angle of each input pulse signal, and the pulse generation angle sequence is stored in the memory 36 for each pick.

  Next, in step S2, an average value of the weft arrival timing is calculated, and a table of generation angles of signal generation pulses when it is determined that there is a weft as shown in FIG. 6 is created. The table data and the average value of the weft arrival timing are sequentially updated.

  Next, in step S3, it is determined whether or not there is a pulse generation angle smaller than the average value of the weft arrival timing. If there is a pulse generation angle smaller than the average value of the weft arrival timing, the process proceeds to step S4.

  Next, based on the table in step S4, the pulse generation angle closest to the average value of the weft arrival timing (including coincidence) from the pulse generation angle sequence (that is, including the coincidence), that is, the smallest difference from the average value is determined as the provisional weft arrival timing (provisional TW ).

  Next, in step S5, the difference θf1 between the provisional weft arrival timing (provisional TW) and the immediately preceding pulse generation angle is compared with a preset first comparison value Tfwd. If the difference θf1 is greater than or equal to the first comparison value Tfwd, step S5 is performed. Proceeding to S6, the provisional weft arrival timing (provisional TW) is set as the weft arrival timing.

  In step S5, if the difference θf1 is less than the first comparison value Tfwd, the process proceeds to step S7. After the previous pulse generation angle is set as a new temporary weft arrival timing (temporary TW), the process proceeds to step S8, and new in step S8. The difference θf2 between the temporary weft arrival timing (temporary TW) and the immediately preceding pulse generation angle is compared with the first comparison value Tfwd.

  If the difference θf2 is greater than or equal to the first comparison value Tfwd in step S8, the process proceeds to step S9, and a new provisional weft arrival timing (provisional TW) is set as the weft arrival timing. If the difference θf2 is less than the first comparison value Tfwd in step S8, the process proceeds to the next step S10. After the previous pulse generation angle is set as a new temporary weft arrival timing (temporary TW), the process proceeds to the next step. The difference θfn between the new provisional weft arrival timing (provisional TW) and the immediately preceding pulse generation angle is equal to or greater than the first comparison value Tfwd, or the generation of the smallest pulse in the provisional weft arrival timing in the pulse generation angle sequence Repeat until the angle is reached. When the difference θfn between the new provisional weft arrival timing (provisional TW) and the immediately preceding pulse becomes equal to or greater than the first comparison value Tfwd in step Sn, the process proceeds to step S (n + 1), and the new provisional weft arrival timing ( Temporary TW) is defined as the weft arrival timing. When the provisional weft arrival timing (provisional TW) becomes the smallest pulse generation angle in the pulse generation angle sequence, the provisional weft arrival timing (provisional TW) is set as the weft arrival timing in step S (n + 2). And

  If there is no pulse generation angle smaller than the average value of the weft arrival timing in step S3, the process proceeds to step S (n + 3), and the pulse closest to the average value (including coincidence), that is, the pulse having the smallest difference from the average value. After the generation angle is set to the provisional weft arrival timing (provisional TW), the process proceeds to step S (n + 4). In step S (n + 4), the difference θr1 between the provisional weft arrival timing (provisional TW) and the immediately following pulse generation angle is compared with a preset second comparison value Trea, and the difference θr1 is less than the second comparison value Trea. Then, the process proceeds to step S (n + 5), and the provisional weft arrival timing (provisional TW) is set as the weft arrival timing. If the difference θr1 is greater than or equal to the second comparison value Trea in step S (n + 4), the process proceeds to step S (n + 6), and the next pulse generation angle is set as a new provisional weft arrival timing (provisional TW). Go to n + 7). In step S (n + 7), the difference θr2 between the new provisional weft arrival timing (provisional TW) and the immediately following pulse generation angle is compared with the second comparison value Trea, and if the difference θr2 is less than the second comparison value Trea, the step. Proceeding to S (n + 8), the new provisional weft arrival timing (provisional TW) is set as the weft arrival timing. If the difference θr2 is greater than or equal to the second comparison value Trea in step S (n + 7), the process proceeds to the next step S (n + 9), and the next pulse generation angle is set as a new temporary weft arrival timing (provisional TW). Proceed to step. Thereafter, the same procedure is followed, whether the difference θrn between the new provisional weft arrival timing (provisional TW) and the immediately following pulse generation angle is equal to or greater than the second comparison value Trea, or the provisional weft arrival timing (provisional TW) is the pulse generation angle. Repeat until the largest pulse generation angle in the row, that is, the last pulse generation angle is reached. Then, when the difference θrn between the new provisional weft arrival timing (provisional TW) and the immediately following pulse generation angle becomes less than the second comparison value Trea in step S (2n), the process proceeds to step S (2n + 1). The temporary weft arrival timing (provisional TW) is defined as the weft arrival timing. In addition, when the temporary weft arrival timing (temporary TW) becomes the largest in the pulse generation angle sequence in step S (2n), that is, when it becomes the last pulse generation angle, in step S (2n + 2), The temporary weft arrival timing (temporary TW) is defined as the weft arrival timing (TW).

  For example, as shown in FIG. 3 (a), there are a plurality of pulse signals across the average weft arrival timing (average TW), and the intervals d1, between three pulse generation angles P1, P2, P3 smaller than the average TW When d2 is less than the value of the first comparison value Tfwd, the following occurs. Since the pulse generation angle P1 is closest to the average value of the weft arrival timing and smaller than the average value, the pulse generation angle P1 becomes a temporary TW, and the interval d1 between the pulse generation angle P1 and the pulse generation angle P2 becomes θf1 in the flowchart. An interval d2 between the pulse generation angle P2 and the pulse generation angle P3 is θf2 in the flowchart. In step S5 of the flowchart described above, since the difference θf1 is not equal to or greater than the first comparison value Tfwd, the process proceeds to step S7. In step S7, after the pulse generation angle P2 becomes the temporary TW, the process proceeds to step S8, and the difference θf2 between the pulse generation angle P2 and the pulse generation angle P3 is compared with the first comparison value Tfwd. Since the difference θf2 is not equal to or greater than the first comparison value Tfwd, the process should proceed to the next step. However, since there is no pulse signal before the pulse generation angle P3, the pulse generation angle P3 becomes the weft arrival timing.

  Further, as shown in FIG. 3B, there are a plurality of pulse signals across the average weft arrival timing (average TW), and the intervals d1, between the three pulse generation angles P1, P2, P3 smaller than the average TW Of d2 ′, the interval d1 is smaller than the value of the first comparison value Tfwd, and the interval d2 ′ is larger than the value of the first comparison value Tfwd. Since the pulse generation angle P1 is closest to the average value of the weft arrival timing and smaller than the average value, the pulse generation angle P1 is a temporary TW. In step S5 of the flowchart, since the interval d1, that is, the difference θf1 is not equal to or greater than the first comparison value Tfwd, the process proceeds to step S7. In step S7, the pulse generation angle P2 becomes the temporary TW. Thereafter, the process proceeds to step S8, where the interval d2 between the pulse generation angle P2 and the pulse generation angle P3, that is, the difference θf2 is compared with the first comparison value Tfwd. Since the difference θf2 is equal to or greater than the first comparison value Tfwd, the process proceeds to step S9, and the pulse generation angle P2 becomes the weft arrival timing.

  Further, as shown in FIG. 3C, there are three pulse generation angles P1, P2, P3 larger than the average TW, and among the intervals d1 ′, d2 of the three pulse generation angles P1, P2, P3. When the interval d1 ′ is larger than the value of the second comparison value Trea and the interval d2 is smaller than the value of the second comparison value Trea, the following occurs. In this case, since there is no pulse generation angle smaller than the average value of the weft arrival timing, in step S (n + 3) of the flowchart, the pulse generation angle P1 is set as the temporary TW and the process proceeds to step S (n + 4). The difference θr1 from the immediately subsequent pulse generation angle P2 is compared with the second comparison value Trea. Since the difference θr1 is not less than the second comparison value Trea, the process proceeds to step S (n + 6). In step S (n + 6), the pulse generation angle P2 is set as a new temporary TW, and then the process proceeds to step S (n + 7). In step S (n + 7), the difference θr2 between the pulse generation angle P2 and the pulse generation angle P3 is compared with the second comparison value Trea. Since the difference θr2 is less than the second comparison value Trea, the process proceeds to step S (n + 8), and the pulse generation angle P2 is set as the weft arrival timing.

  Next, a method for detecting the weft arrival timing will be described with reference to the table of FIG. The table shows the pulse generation angles confirmed when it is determined that there is a weft, and shows a pulse generation angle sequence for each pick. The detection range is a machine base angle of 210 to 310 °, the average TW is 244 °, the first comparison value Tfwd = 5 °, and the second comparison value Trea = 5 °.

  For example, in the No. 3 pick, a pulse generation angle earlier (smaller) than the average value 244 ° is searched. Since there is a pulse generation angle at 242 °, it becomes a weft arrival timing (TW) candidate (temporary weft arrival timing). Since there is no pulse signal before that, 242 ° is the weft arrival timing (TW).

  In the No. 15 pick, the pulse generation angle is 243 ° earlier (smaller) than the average value 244 °, and therefore, the weft arrival timing (TW) is a candidate (temporary weft arrival timing). Before that, there is 219 °, but since it is 5 ° or more away from the temporary weft arrival timing 243 °, 243 ° is the weft arrival timing (TW).

  In the No. 1 pick, since there is no pulse generation angle earlier (smaller) than the average value 244 °, a pulse generation angle later (larger) than the average value 244 ° is searched. Since there is a pulse generation angle at 250 °, it becomes a weft arrival timing (TW) candidate (temporary weft arrival timing). Since the later angle is 254 ° and not more than 5 °, 250 ° is the weft arrival timing (TW).

Similarly, when the weft arrival timing (TW) is searched for in the pulse generation angle trains of other picks, the generation angle shaded in FIG. 6 becomes the weft arrival timing (TW).
According to this embodiment, the following effects can be obtained.

  (1) The weft detection method uses the average value when the pulse generation angle sequence of the output pulses output from the photoelectric weft detector (weft feeler 31) has a pulse generation angle smaller than the average value of the weft arrival timing. The pulse generation angle with the smallest difference is set as the temporary weft arrival timing. Then, the difference between the provisional weft arrival timing and the pulse generation angle immediately before is compared with the first comparison value. If the difference is equal to or greater than the first comparison value, the provisional weft arrival timing is set as the weft arrival timing, and the difference is the first comparison. If it is less than the value, the pulse generation angle immediately before the provisional weft arrival timing is set as a new provisional weft arrival timing. Then, the difference between the new provisional weft arrival timing and the immediately preceding pulse generation angle is compared with the first comparison value. If the difference is equal to or greater than the first comparison value, the new provisional weft arrival timing is set as the weft arrival timing. This is repeated until the difference between the new provisional weft arrival timing and the pulse generation angle immediately before it becomes equal to or greater than the first comparison value, or the provisional weft arrival timing reaches the smallest pulse generation angle in the pulse generation angle sequence.

  Further, when there is no pulse generation angle smaller than the average value in the pulse generation angle sequence, the pulse generation angle that is larger than the average value and has the smallest difference from the average value is set as the temporary weft arrival timing, The difference from the immediately following pulse generation angle is compared with the second comparison value, and if the difference is less than the second comparison value, the provisional weft arrival timing is set as the weft arrival timing, and if the difference is greater than or equal to the second comparison value, the provisional weft arrival timing The immediately following pulse generation angle is set as a new provisional weft arrival timing, the difference between the new provisional weft arrival timing and the immediately following pulse generation angle is compared with the second comparison value, and if the difference is less than the second comparison value, a new The procedure for setting the weft arrival timing as the weft arrival timing is determined based on whether the difference between the new weft arrival timing and the immediately following pulse generation angle is less than the second comparison value or the weft Repeated until arrival timing is the largest pulse generating angle among the pulse generating angle train. According to this configuration, accurate weft arrival timing can be detected without being affected by the amount of fluff.

  (2) The weft detection device is a weft detection device in a jet loom that detects a weft arrival angle based on an output pulse of a photoelectric weft detector (weft feeler 31) that detects a weft. A pulse generation angle applying means for applying a pulse generation angle to the pulse signal input from the photoelectric weft detector; and a pulse generation angle array for generating a pulse generation angle array based on the pulse generation angle of each input pulse signal. A creation means, a pulse angle string storage means for storing a pulse generation angle string for each pick, and an average weft arrival timing calculation means are provided. Further, when the pulse generation angle sequence stored in the pulse angle sequence storage means has a pulse generation angle smaller than the average value of the weft arrival timing, the pulse generation angle having the smallest difference from the average value is set as the provisional weft arrival timing. The difference between the first weft arrival timing setting means and the provisional weft arrival timing set by the first provisional weft arrival timing setting means and the pulse generation angle immediately before is compared with the first comparison value. If the comparison value is greater than or equal to the comparison value, the temporary weft arrival timing is set as the weft arrival timing. If the difference is less than the first comparison value, the pulse generation angle immediately before the temporary weft arrival timing is set as the new temporary weft arrival timing. The difference from the previous pulse generation angle is compared with the first comparison value, and if the difference is equal to or greater than the first comparison value, the new provisional weft arrival timing is set to the weft arrival timing. The difference between the new provisional weft arrival timing and the immediately preceding pulse generation angle is greater than or equal to the first comparison value, or the provisional weft arrival timing is the smallest pulse generation angle in the pulse generation angle sequence. First weft arrival timing determination means that repeats until

  Further, when there is no pulse generation angle smaller than the average value in the pulse generation angle row, the weft detection device uses the pulse generation angle that is larger than the average value and has the smallest difference from the average value as the provisional weft arrival timing. The difference between the second weft arrival timing setting means and the provisional weft arrival timing set by the second false weft arrival timing setting means and the pulse generation angle immediately thereafter is compared with the second comparison value, and the difference is the second If the difference is less than the comparison value, the temporary weft arrival timing is set as the weft arrival timing. If the difference is equal to or greater than the second comparison value, the pulse generation angle immediately after the temporary weft arrival timing is set as the new temporary weft arrival timing. The difference from the immediately following pulse generation angle is compared with the second comparison value. If the difference is less than the second comparison value, the new provisional weft arrival timing is set as the weft arrival timing. In order, until the difference between the new provisional weft arrival timing and the immediately following pulse generation angle becomes less than the second comparison value, or the provisional weft arrival timing reaches the largest pulse generation angle in the pulse generation angle sequence Repeating second weft arrival timing determination means.

According to this configuration, the weft detection method can be implemented. Therefore, it is possible to detect the accurate weft arrival timing without being affected by the amount of fluff.
(3) The weft detection device includes a first comparison value setting unit 45 that sets the first comparison value Tfwd and a second comparison value setting unit 46 that sets the second comparison value Trea. A preset value may be used as the first comparison value Tfwd and the second comparison value Trea. However, if the first comparison value setting unit 45 and the second comparison value setting unit 46 are provided, the first comparison value Tfwd and the second comparison value Trea can be used according to the weaving conditions. Therefore, the first comparison value Tfwd and the second comparison value Trea that are more suitable can be set.

  (4) The weft detection device includes a setting screen 42 for displaying and setting the first comparison value Tfwd and the second comparison value Trea set by the first comparison value setting unit 45 and the second comparison value setting unit 46. Yes. The setting screen 42 only needs to be able to input a setting value, and the setting value may not be displayed. However, when the set value is displayed, it is easier for the operator to prevent erroneous input by confirming the set value.

The embodiment is not limited to the above, and may be embodied as follows, for example.
The setting screen 42 for displaying the first comparison value Tfwd and the second comparison value Trea set by the first comparison value setting unit 45 and the second comparison value setting unit 46 may be omitted. However, when the set value is displayed, the operator can easily confirm the set value, and it is easy to prevent erroneous input.

  ○ The first comparison value Tfwd and the second comparison value Trea are not input by the operator, but a plurality of first comparison values Tfwd and second comparison values Trea are previously stored in the memory 36 of the control device C in accordance with the weaving conditions. The first comparison value Tfwd and the second comparison value Trea that are stored and suitable for the weaving conditions may be automatically set by the control device C.

The detection of the weft arrival timing is not limited to the weft detection method using pulses, but may be performed using the yarn signal integration method.
○ The tandem nozzle 13 may be omitted.

  Y ... Weft, P1, P2, P3 ... Pulse generation angle, TW ... Weft arrival timing, Tfwd ... First comparison value, Trea ... Second comparison value, 31 ... Weft feeler as photoelectric weft detector, 35 ... Pulse generation Angle providing means, pulse generation angle train creating means, average weft arrival timing calculating means, first temporary weft arrival timing setting means, first weft arrival timing determining means, second temporary weft arrival timing setting means, and second weft arrival timing determination CPU as means, 36... Memory as pulse angle sequence storage means, 45... First comparison value setting section as setting section, 46... Second comparison value setting section as setting section.

Claims (3)

A weft detection method in a jet loom for detecting a weft arrival angle by an output pulse of a photoelectric weft detector for detecting a weft,
If the pulse generation angle sequence of the output pulse output from the photoelectric weft detector has a pulse generation angle smaller than the average value of the weft arrival timing, the pulse generation angle with the smallest difference from the average value is set to the temporary weft arrival A difference between the provisional weft arrival timing and the immediately preceding pulse generation angle is compared with a first comparison value. If the difference is equal to or greater than the first comparison value, the provisional weft arrival timing is defined as a weft arrival timing. Is less than the first comparison value, the pulse generation angle immediately before the provisional weft arrival timing is set as a new provisional weft arrival timing, and the difference between the new provisional weft arrival timing and the pulse generation angle immediately before is determined in the first comparison. If the difference is equal to or greater than the first comparison value, the procedure for setting the new temporary weft arrival timing as the weft arrival timing is referred to as a new temporary weft arrival timing. Timing and its or the difference between the pulse generation angle immediately before is equal to or greater than the first comparative value, or said repeated until temporary weft arrival timing is the smallest pulse generating angle among the pulse generating angle train,
When there is no pulse generation angle smaller than the average value in the pulse generation angle row, a pulse generation angle that is larger than the average value and has the smallest difference from the average value is set as the temporary weft arrival timing, and the temporary weft arrival timing The difference between the timing and the pulse generation angle immediately thereafter is compared with the second comparison value. If the difference is less than the second comparison value, the provisional weft arrival timing is set as the weft arrival timing, and the difference is greater than or equal to the second comparison value. Then, the pulse generation angle immediately after the provisional weft arrival timing is set as a new provisional weft arrival timing, and the difference between the new provisional weft arrival timing and the immediately following pulse generation angle is compared with the second comparison value. Is less than the second comparison value, the procedure for setting the new provisional weft arrival timing as the weft arrival timing is used as the new provisional weft arrival timing and the immediately following pulse generation. Weft detection method in a jet loom which difference between the degree is equal to or repeated until the or the temporary weft arrival timings second becomes less than the comparison value is the largest pulse generating angle among the pulse generating angle train. A weft detection device in a jet loom for detecting a weft arrival angle by an output pulse of a photoelectric weft detector for detecting a weft,
Pulse generation angle applying means for applying a pulse generation angle to the pulse signal input from the photoelectric weft detector;
Pulse generation angle sequence creating means for creating a pulse generation angle sequence based on the pulse generation angle of each input pulse signal;
Pulse angle sequence storage means for storing the pulse generation angle sequence for each pick;
An average weft arrival timing calculating means;
When the pulse generation angle sequence stored in the pulse angle sequence storage means has a pulse generation angle smaller than the average value of the weft arrival timing, the pulse generation angle having the smallest difference from the average value is set as the provisional weft arrival timing. First temporary weft arrival timing setting means,
The difference between the provisional weft arrival timing set by the first provisional weft arrival timing setting means and the pulse generation angle immediately before is compared with a first comparison value, and if the difference is equal to or greater than the first comparison value, the provisional weft The arrival timing is the weft arrival timing, and if the difference is less than the first comparison value, the pulse generation angle immediately before the provisional weft arrival timing is the new provisional weft arrival timing, and the new provisional weft arrival timing and the immediately preceding pulse The difference between the generated angle and the first comparison value is compared, and if the difference is equal to or greater than the first comparison value, the procedure for setting the new provisional weft arrival timing as the weft arrival timing is the new provisional weft arrival timing and immediately before it. The difference between the pulse generation angle and the pulse generation angle is equal to or greater than the first comparison value, or the temporary weft arrival timing is the smallest in the pulse generation angle sequence. A first weft arrival timing determining means repeats until the angle,
When there is no pulse generation angle smaller than the average value in the pulse generation angle row, the second temporary weft yarn having a pulse generation angle larger than the average value and having the smallest difference from the average value as the temporary weft arrival timing. Arrival timing setting means;
The difference between the provisional weft arrival timing set by the second provisional weft arrival timing setting means and the pulse generation angle immediately thereafter is compared with a second comparison value, and if the difference is less than the second comparison value, the provisional weft arrival is reached. If the timing is the weft arrival timing and the difference is equal to or greater than the second comparison value, the pulse generation angle immediately after the provisional weft arrival timing is set as a new provisional weft arrival timing, and the new provisional weft arrival timing and pulse generation immediately thereafter are generated. The difference between the angle and the second comparison value is compared, and if the difference is less than the second comparison value, the procedure for setting the new provisional weft arrival timing as the weft arrival timing is the new provisional weft arrival timing and the immediately following The difference between the pulse generation angle is less than the second comparison value, or the provisional weft arrival timing is the largest in the pulse generation angle sequence. A second weft arrival timing determining means repeats until,
A weft detection device in a jet loom characterized by comprising:   The weft detection device in a jet loom according to claim 2, further comprising a setting unit that sets the first comparison value and the second comparison value.