JPH0672345B2 - Weft length measuring method for shuttleless loom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a weft measuring method in a shuttleless loom.

(Prior Art) Generally, in a jet loom, it is necessary to constantly measure the amount of weft yarns inserted from the jetting fluid and keep it at a constant value. As an apparatus for performing this type of measurement, for example, Japanese Patent Laid-Open No.
There is one shown in No. 29640. This device locks and unwinds the weft yarn stored on the drum with a solenoid pin that can be brought into and out of contact with the outer peripheral surface of the drum at regular intervals, and the weft yarn is unwound once every time the weft yarn is unwound and unwound. Is detected by the sensor and a signal is output to the control system to start the counting operation. When the counted value reaches a predetermined value set corresponding to the required weft insertion amount of the weft, the solenoid pin locks the weft on the outer peripheral surface of the drum and stops the weft insertion operation.

In this type of device, even if a cotton fly or the like passes through the detection area of the sensor, the sensor may detect it and output an erroneous signal to the control system, resulting in malfunction of the control system.
The frequency of malfunctions by this control system increases in proportion to the number of times the sensor operates. Therefore, in the above-described device in which the sensor detects the passage of the weft each time the weft is unwound and unwound, the number of malfunctions by the control system increases, and the length of the weft may not be accurately measured.

Further, in the weft supply device disclosed in JP-A-59-125944, when the weft stored on the drum is pulled out,
The first rewinding, the next rewinding and the rewinding are detected by the detector and a detection signal is output to the control system. Based on the time between the first detection signal and the next detection signal, weft insertion of the weft ends. It calculates time. Then, the solenoid pin is brought into contact with the outer peripheral surface of the drum in accordance with the calculated time to regulate the unwinding of the weft.

However, even in this device, since the detector operates twice, the detector frequently outputs an erroneous signal due to the passage of the cotton dust, etc., and there is room for improvement in the weft length measurement error due to the malfunction of the control system. There is.

(Problems to be Solved by the Invention) As described above, the present invention is intended to solve the problem that the control system malfunctions at the time of weft insertion, resulting in many weft length measurement errors. An object of the present invention is to provide a weft length measuring method in a shuttleless loom, which can perform highly accurate weft length measurement by reducing the operation of detecting the unwinding of the weft.

Configuration of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, according to the present invention, the weft engaging means separates from the drum in one weft insertion, and the first unwinding of the weft. The movement is detected to measure the time between both movements, the time required for unwinding the weft necessary for weft insertion is calculated based on this measurement time, and the weft locking means is operated based on the calculation result. It adopts a means of contacting the outer peripheral surface of the drum to prevent the unwinding of the weft.

(Operation) By adopting the above-mentioned means, the present invention detects only the passage of the weft that is first unwound when the weft is inserted.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings.

A motor 2 whose speed is controlled by a motor rotation speed control device 1 such as an inverter is mounted and supported on one side of a loom (not shown), and a drive gear 4 is fixed to a front end portion of a motor shaft 3 of the motor 2. ing.

Above the drive gear 4, a driven gear 5 meshing with the drive gear 4 is provided.
Is provided, and the rotary shaft 6 of the driven gear 5 is provided with a yarn guide hole 6a along the axis. The rotating shaft 6 is supported at the front by a supporting frame 7 so as to be relatively rotatable, and a first locking gear 8 fixed to the front surface of the supporting frame 7.
And is attached to a hollow rotary bracket 9 so as to be integrally rotatable. A cylindrical bobbin winding arm 10 is fixed to the rotating bracket 9 so as to be oblique to the rotating shaft 6, and a front end thereof is opened near an outer peripheral surface described later.

A second locking gear 12 facing the rotation bracket 9 is supported at the tip of the rotary shaft 6 so as to be rotatable relative to it, and a drum 11 is fixed to the front surface of the second locking gear 12 via a bracket 13. Has been done. The weft yarn Y supplied from the cheese T is wound around the yarn winding surface of the drum 11 via the yarn introducing hole 6a and the yarn winding arm 10.

A support 14 is fixed to the rotating bracket 9,
A pair of planetary gears 17 and 18 fixed to both sides of the support 14 via a mounting shaft 15 mesh with the first and second locking gears 8 and 12, respectively. When the rotary shaft 6 and the rotary bracket 9 rotate as the motor 2 rotates,
Since 14 also rotates around the rotating shaft 6 and both planetary gears 17 and 18 revolve while meshing with the first and second locking gears 8 and 12, both locking gears 8 and 12 do not rotate. As a result, the bracket 13 and the drum 11 are held stationary. The stationary state of the drum 11 can be held by a known means such as using a magnet or a weight.

Near the outer peripheral surface of the front portion of the drum 11, a locking pin 19 as a weft locking means is projected and withdrawn by an electromagnetic solenoid S.
Is provided, and the electromagnetic solenoid S is electrically connected to the control unit C via the solenoid drive unit 20. And
The electromagnetic solenoid S is excited based on the signal output from the control unit C, the locking pin 19 is engaged with the outer peripheral surface of the drum 11 so as to be able to come into contact with and separate from the drum 11, and the weft yarn Y wound and stored on the drum 11 is stored. The withdrawal is regulated.

Similarly, a first reflection type photoelectric sensor 21 having a light projecting portion and a light receiving portion is arranged in the vicinity of the outer peripheral surface of the front portion of the drum 11, and the weft Y of a predetermined amount or more is stored on the outer peripheral surface of the drum 11. It is designed to detect whether or not there is. The photoelectric sensor 21 is electrically connected to the control unit C via the waveform shaping unit 22,
The operation of the motor 2 is controlled via the control unit C in accordance with the amount of the weft Y accumulated on the drum 11.

Further, a second reflection type photoelectric sensor 23 is arranged in the vicinity of the outer peripheral surface of the front part of the drum 11 with a phase difference of 180 ° with the locking pin 19, and the weft yarn Y stored on the outer peripheral surface of the drum 11 is unwound. When unwinding, the first rewinding of the same weft yarn Y is detected. The photoelectric sensor 23 includes a waveform shaping unit 24 and a timer 24a.
Is electrically connected to the control unit C via.

Reference numeral 27 in FIG. 1 denotes a main nozzle in which the weft yarn Y unwound on the outer peripheral surface of the drum 11 is provided.
Are to be drawn in by the jet of fluid.

As shown in FIG. 3, the computer 28 of the control unit C is shown.
A preset weft insertion amount n (indicating the number of turns on the drum 11) of the weft Y is set in a central processing unit CPU, a read-only memory ROM, and a readable / rewritable memory RAM. It has been entered.

As shown in FIG. 1, the locking pin 19 is in contact with the outer peripheral surface of the drum 11, and the weft Y is wound and stored on the outer peripheral surface of the drum 11 in a required amount. At this time, the motor 2 is stopped and the bobbin winding arm 10 is also stationary. When the machine stand rotates from this state and the machine stand rotation angle reaches a predetermined value, the control section C outputs an operation command to the solenoid drive section 20 and the timer 24a based on the detection signal from the machine stand rotation angle detection device 26. .

The solenoid drive unit 20 demagnetizes the electromagnetic solenoid S based on the operation command from the control unit C, and causes the locking pin 19 to retract as shown in FIG. 2 to separate it from the outer peripheral surface of the drum 11. At the same time, the timer 24a starts the time measuring operation based on the operation command from the control section C.

When the locking pin 19 is separated from the outer peripheral surface of the drum 11, the weft Y that is wound and stored on the outer peripheral surface of the drum 11 is pulled out from the drum 11 based on the fluid jet from the main nozzle 27, and the weft Y is It is fed into the main nozzle 27 and weft insertion is started.

At the time of weft insertion described above, when the weft Y is pulled out,
The weft Y on the drum 11 is unwound, and the passage of the weft Y that is first rewound is detected by the second reflective photoelectric sensor 23. Then, the photoelectric sensor 23 outputs a weft passing signal to the timer 24a to stop the time measuring operation of the timer 24a. Therefore, the timer 24a measures the time t from the time when the locking pin 19 exits, that is, from the start of weft insertion to the rewinding of the first half winding of the weft Y, and outputs it to the control unit C.

Then, the control unit C multiplies the time required to unwind the weft insertion required amount based on the measurement time t, that is, the value obtained by multiplying t by the difference between the previously input weft insertion required amount n and the first rewinding amount. (N-1 / 2) 2t is calculated, and from the first half turn rewinding, (n
-3/2) 2t has passed, and an operation command is sent to the solenoid drive unit 20 in consideration of a slight response delay while reaching (n-1 / 2) 2t. Therefore, the locking pin 19 projects into the unwinding of the n-th winding yarn and contacts the outer peripheral surface of the drum 11, whereby the unwinding of the weft yarn Y is restricted to n windings and the weft insertion is completed. .

Also, the weft Y on the drum 11 during the pulling out of the weft Y
When the winding storage amount is gradually decreased and the storage amount becomes equal to or less than a predetermined amount, the first photoelectric sensor 21 detects this and outputs a weft storage amount detection signal to the control unit C. Then, the control unit C sends an operation command to the motor 2 based on the storage amount detection signal until the amount of the weft yarn Y stored on the outer peripheral surface of the drum 11 becomes equal to the required storage amount of the weft yarn.

As described above, in the present invention, when the weft Y is inserted, only the passage of the weft Y that is first rewound is detected by the photoelectric sensor 23.
And outputs a weft passing signal to the control unit C, and the control unit C measures the time required at the start of weft insertion and the time required for one weft insertion based on this passage signal. Therefore, the frequency of occurrence of a detection error due to foreign matter such as fly dust is low, and the detection accuracy is extremely high. Therefore, the malfunction of the control unit C is reduced, and stable measurement operation can be performed.

EFFECTS OF THE INVENTION As described in detail above, the present invention detects the operation of the weft locking means separating from the drum in one weft insertion and the first rewinding operation of the weft, and detects the time between both operations. The time taken for the weft to be unwound for weft insertion is calculated based on the measured time, and the weft locking means is brought into contact with the outer peripheral surface of the drum based on the result of the calculation to prevent the weft from being unwound. As a result, it is possible to reduce the operation for detecting the unwinding of the weft yarn, and to perform an excellent effect that the weft yarn length can be measured with high accuracy.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment embodying the present invention,
2 is a partially cutaway side view showing a change from FIG. 1, FIG.
The figure is a block diagram showing a control unit. Drum 11, weft lock pin 19, weft Y.

Claims (1)

[Claims] 1. A rotary drive mechanism stores and winds the weft around an outer peripheral surface of the drum, and a weft locking means that abuts on the outer peripheral surface of the drum prevents unwinding of the weft. A weft measuring method in which the weft is pulled out from the outer peripheral surface of the drum, and the operation of the weft locking means separating from the drum and the first rewinding operation of the weft are detected in one weft insertion. The time between both operations is measured, and the time required for unwinding the weft necessary for weft insertion is calculated based on this measured time, and the weft locking means is applied to the outer peripheral surface of the drum based on the calculation result. A weft measuring method for a shuttleless loom that comes into contact with the weft to prevent it from unwinding.