JPH0466939B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a weft processing method in a fluid jet loom such as an air jet loom or a water jet loom.

Prior Art Unlike conventional shuttle looms, this type of fluid jet loom uses a fluid such as air or water to make the weft threads fly through the upper and lower warp openings without using a shuttle. Weft insertion errors are more likely to occur compared to shuttle looms. In addition, in fluid injection looms operating at high speed, even if the loom is stopped immediately after a weft insertion error is discovered, each part of the loom will not be damaged by excessive force due to sudden deceleration. In order to prevent this, the timing is set so that the machine stops after approximately one cycle of inertial operation after detecting a weft insertion error. Therefore, even if the loom starts to stop due to the weft insertion error signal, the next weft insertion cycle will be completed before the loom actually stops. Therefore, it is necessary to reverse the machine and remove not only the weft yarn that caused the weft insertion error, but also the weft yarn that was inserted in the cycle after the weft insertion error. However, the weft yarns inserted in this cycle are beaten like normal weft yarns and are firmly held in the woven fabric, making the removal work extremely complicated.
Moreover, when reversing as described above, it is necessary to operate each part of the loom and operate the loom according to complicated work procedures in order to repair the weft insertion error and restart the loom.
This requires a great deal of skill.

Additionally, if the weft yarn (including the selvage yarn) is cut during weaving work or the loom switch is turned off due to manual operation, the loom will lose its inertia due to the above-mentioned reasons.
It will stop after running for about a cycle. If it is attempted to remove the weft inserted during this inertial movement in order to prevent defects such as weaving steps from occurring in the woven fabric, it is not easy to remove it for the reasons described above.

In view of these circumstances, the applicant of the present invention,
As disclosed in Japanese Patent Application Laid-Open No. 58-197339, when a loom stop signal is detected, the loom is braked while preventing weft insertion until the loom stops, and then the weft is stopped between the upper and lower warps. This paper proposes a weft processing method for a fluid jet loom, which is characterized by reversing the loom to a state where the weft to be removed can be processed without supplying the weft to the weft. However, in this prior art processing method, a suction nozzle is used in the embodiment to prevent weft insertion, and problems that need to be solved arise with the use of the suction nozzle.

That is, as shown in FIG. 1, an example of a weft insertion mechanism that implements the above-mentioned processing method is as shown in FIG.
is fed from the cheese 2 via the tensor 3 by the feed roller 4 and stored in the pool pipe 6 by the air nozzle 5. A drive drum 7 that moves on the crankshaft of a loom (not shown) frictionally drives the feed roller 4, and a predetermined length of weft 1 is measured by the feed roller 4 according to the rotation of the crankshaft and is supplied to the air nozzle 5. A slit 8 is provided in the pool pipe 6, and the weft yarn 1 passes through the slit 8 and exits the pipe during weft insertion. A gripper 10 is provided between the pool pipe 6 and the main nozzle 9, and controls the supply of the weft yarn 1 from the pool pipe 6 to the main nozzle 9.
The main nozzle 9 and the gripper 10 are also synchronized with the rotation of the crankshaft, and the gripper 10 opens at a predetermined timing to release the weft 1, and the main nozzle 9 injects compressed air to move the weft 1 between the upper and lower warps.
is inserted into the weft, and the reed 11 beats it. 12 and 13 are detectors of an appropriate type provided near the selvage yarn on the opposite side of the main nozzle 9 in order to detect whether or not the weft yarn has been inserted reliably. 14
In order to prevent the weft in the main nozzle 9 from being pulled back to the pool pipe 6 side by the air flow from the air nozzle 5 when the machine is reversed, the gripper 10 is
This is an auxiliary gripper provided on the main nozzle side of the main nozzle, and is opened and closed by an electromagnetic solenoid 15 or an air cylinder (not shown).

The feed roller 4 described above is rotatably supported at the tip of an arm 17 that is rotatably supported around a pin 16. A spring 18 is stretched over the end of the arm 17 opposite to the feed roller supporting end, and is biased so that the arm 17 always comes into contact with the piston of the air cylinder 19. Therefore, by the action of the spring 18 and the air cylinder 19, the feed roller 4 can be in a state where it is pressed against the length measuring drum 7 and driven by friction, or a state where it is separated from the length measuring drum 7 and not driven.

According to the invention described in JP-A-58-197339, the weft insertion mechanism is further provided with a suction nozzle 20 such as an ejector type between the main nozzle 9 and the selvage yarn, and an air cylinder or an electromagnetic A suitable reciprocating member 21 such as a solenoid is connected to the suction nozzle 20, and when the reciprocating member 21 operates, a guide plate 22 attached to the tip of the suction nozzle 20 is ejected from the main nozzle 9. It is movable between an exit position outside the weft path and an entry position on the weft path. 23 is a weft cutting cutter attached near the tip of the main nozzle 9, and 24 is a valve that controls the timing of air jetting into the suction nozzle 20.

The weft insertion mechanism operates as described in detail in the above publication, but to explain the parts that are closely related to the present invention, in FIGS. 1 and 2, for example, a weft insertion error occurs. When the detectors 12 and 13 detect this and generate a stop signal,
The machine enters inertia operation, the valve 24 opens and the suction nozzle 20 starts suction, and the guide plate 22 enters the entry position due to the operation of the reciprocating member 21. Therefore, the weft yarn ejected from the main nozzle 9 during the inertial rotation of the machine frame is guided by the guide plate 22 located at the entry position (FIG. 1) and passes through the suction nozzle 20.
It is not inserted between the upper and lower warp threads. The machine rotates by inertia for about one cycle, then stops, and in accordance with the procedure described in the above-mentioned publication, reverses the machine, stops to remove the wrong thread, reverses to the crank angle position necessary for restarting, stops the machine, A restart is performed and normal operation resumes. On the other hand, the guide plate 22 remains in the entry position until just before the restart, and the valve 24 also remains open until just before the restart.

If we consider only to prevent the weft yarn of the weft insertion cycle from being inserted between the upper and lower warp yarns during the inertial rotation of the machine frame, suction by the suction nozzle 20 is necessary during the inertial rotation of the machine frame shown in Fig. 2. Only section A is in the middle. However, suction nozzle 2
0 is attached to a fixed machine frame,
Since the main nozzle 9 is generally fixed to a swinging sley (not shown), when the machine is reversed,
With the reversal, a displacement occurs between the main nozzle 9, which swings together with the sley, and the suction nozzle 20, which does not swing. Therefore, as can be understood from Fig. 3 A and B, if the suction period of the suction nozzle 20 is kept only in section A, suction is not performed in section B, so that the suction period in Fig. 3 I If the weft yarn 1 becomes clogged in the suction nozzle 20 as shown in the figure, the weft yarn mass inside the suction nozzle 20 will come out due to the movement of the main nozzle 9 in the direction of the arrow during the reverse rotation, and the When the machine is stopped, the suction yarn cannot be cut by the cutter 23, and even if the machine is restarted, the weft insertion error may occur again, or the weft yarn 1 may be stuck inside the suction nozzle 20 as shown in Fig. 3B. Even if the weft is properly absorbed, the reciprocating movement of the main nozzle 9 in the direction of the arrow during the reverse rotation causes slack in the weft yarn 1 as shown by the chain line, resulting in a cutting error with the arrow tension cutter 23.

Under these circumstances, in the weft processing method described in the above-mentioned Japanese Patent Application Laid-Open No. 58-197339, not only the above-mentioned section A but also the entire section B from the end of the inertial rotation of the machine to the time of restart, The suction nozzle 20 suctions the weft yarn. However, since the suction action of the suction nozzle 20 is controlled only by opening and closing a single valve 24, the suction force is a constant strong force over sections A and B, and the consumption of suction air is extremely large. Not only does this increase the amount of damage, but there is also the problem that the suction force can cause the weft to break, making it impossible to resume normal operation.

OBJECT OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and provide a fluid jet loom that consumes as little suction air as possible and does not hinder the transition to normal operation after stopping. An object of the present invention is to provide a weft processing method in the present invention.

Structure of the Invention In order to achieve the above object, the present invention provides a weft processing method in a fluid jet loom in which a weft is inserted between upper and lower warps by a fluid jet from a main nozzle. After the weft from the main nozzle is suctioned by a suction nozzle near the nozzle at a first predetermined suction force until it fully enters the suction nozzle, the first predetermined suction force is applied for a predetermined period of time until restarting. It is characterized in that suction processing is performed with a second predetermined suction force that is weaker than the suction force.

The first predetermined suction force needs to be strong as in the conventional technology in order to suction the weft jetted at high speed from the main nozzle, but the second predetermined suction force is It is sufficient that the strength is such that the weft yarn mass does not come out or the weft yarn portion between the suction nozzle and the main nozzle becomes slack. In an embodiment, the second predetermined suction force is adjustable by means of a throttle valve.

Embodiment FIG. 4 shows an air supply circuit to the suction nozzle 20 for carrying out the weft processing method according to the present invention. A first solenoid valve 27 corresponding to the valve 24 in FIG. 1, and a first solenoid valve 27
A second solenoid valve 28 is provided in parallel with the flow rate adjustment valve 28, and a throttle valve 29 for flow rate adjustment is connected to the second solenoid valve 28.

The circuit state in FIG. 4 shows the state immediately after the stop signal is issued, and the stop signal is also sent to the solenoid of the first solenoid valve 27 to keep the first solenoid valve 27 open. However, the second solenoid valve 28 is closed. Therefore, in section A, a strong first predetermined suction force similar to that described in Japanese Patent Application Laid-Open No. 58-197339 is applied by the air supplied to the suction nozzle 20 via the second solenoid valve 27. , acts on the weft yarn 1 from the main nozzle 9, and the same weft yarn is sucked into the suction nozzle 20.

Next, as shown in FIG.
The solenoid valve 27 is demagnetized and closed. This time point t may be determined by setting a timer to a time that can be determined empirically, and by setting the timer until this time has elapsed after the stop signal is generated, or by installing an appropriate weft sensor in the suction nozzle to confirm weft suction. This can be set at a predetermined time using a timer, or at the same time as the machine stops using an appropriate means (not shown) for detecting the stopped state. In this way, the first solenoid valve 27 is closed.

The open state of the second electromagnetic valve 28 is maintained for a predetermined period of time after the weft is suctioned with the first predetermined suction force as described above and until the time of restart.

In the timing diagram shown in FIG. 5, this predetermined time is determined by the main nozzle 9 moving in the direction of the arrow in FIG. From time t' when reversal starts until restart, the air from the air supply source 25 is supplied to the second solenoid valve 2.
8, the weft yarn 1 is adjusted to an appropriate amount by a throttle valve 29, and then supplied to a suction nozzle 20, where the weft yarn 1 is sucked with a second predetermined suction force that is weaker than the first predetermined suction force.

In addition, although there is a slight increase in air consumption, the predetermined time period may be from the time when the first solenoid valve 27 is closed to the time of restarting, or the period before restarting, although the problem of Fig. At a relatively late point in time t'' (see Figure 5)
It may be set from to the time of reboot.

Note that the electric circuit for opening and closing the first and second electromagnetic valves as described above is obvious to those skilled in the art, so illustration thereof will be omitted.

Effects of the Invention As described above, according to the present invention, when the machine stop signal is generated, the weft from the main nozzle is sucked into the suction nozzle with the first predetermined suction force, and then the weft yarn is sucked with the first predetermined suction force. Since it is configured to perform suction for a predetermined period of time until restarting with a weak second predetermined suction force, the amount of air consumed for suction is reduced as much as possible, saving energy and preventing thread breakage due to suction. decreases and improves productivity.

Further, the amount of air is adjusted to an optimum amount by throttling with a throttle valve.

Furthermore, in the weft insertion mechanism illustrated in FIG. 1, the gripper 10 is used to prevent the weft in the main nozzle 9 from being pulled back toward the pool pipe 6 by the air flow from the air nozzle 5 when the machine is reversed.
An auxiliary gripper 14 and an electromagnetic solenoid 15 for opening and closing the gripper are provided on the main nozzle side of the main nozzle. The auxiliary gripper 14 and the electromagnetic solenoid 15 can be eliminated.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing an example of a weft insertion mechanism capable of carrying out the weft processing method according to the present invention, and FIG. 2 is a timing diagram of the operational relationship between the machine base, suction nozzle, valve, and guide plate according to the prior art. A diagram showing
Figures 3A and 3B are partial sectional plan views showing problems solved by the prior art, Figure 4 is a solenoid valve piping system diagram for carrying out the weft processing method according to the present invention, and Figure 5 is a diagram of the present invention. It is a figure which shows an example of the operation timing of the machine base, suction nozzle, and 1st, 2nd electromagnetic valve in this invention. In the figure, 1 is the weft, 9 is the main nozzle, 20 is the suction nozzle, 27 is the first solenoid valve, and 28 is the second
The electromagnetic valve 29 is a throttle valve.

Claims (1)

[Claims] 1. In a weft processing method in a fluid jet loom, in which the weft is inserted between the upper and lower warps by a fluid jet from a main nozzle, when a machine stop signal is generated, a suction nozzle near the main nozzle inserts the weft from the main nozzle. After the suction process is performed at the first predetermined suction force until the weft yarn enters the suction nozzle sufficiently, the first
A weft processing method in a fluid jet loom, characterized in that suction processing is performed with a second predetermined suction force that is weaker than a predetermined suction force.