JPH0437174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method of applying tension to a weft by a tensor located between a yarn feeding section and a weft length measuring device of a shuttleless loom.

Prior Art FIG. 1 shows an example of a shuttleless loom in which the method of applying weft tension according to the present invention can be implemented, that is, an air jet loom, in which the weft W from the yarn feeding section 1 is passed through the tensor 2 and then measured for length. After being sent to device 3 and measured in a known manner by the length measuring device, which may be of a known structure as disclosed in Japanese Utility Model Application Publication No. 56-39486, an air nozzle for the weft pool is 4. The weft thread passes through a weft pool pipe 5, a weft guide 6, and a gripper 7, and then reaches an air nozzle 8 for weft flying. The air nozzle 8 also has a sleigh 10 supporting a reed 9.
The weft yarns W, whose lengths are measured by the length measuring device 3, are aligned in the weft insertion direction at the top and are exposed to air flow from an air source (not shown) communicating with the air nozzle 8 during weft insertion. Then, it is inserted into the openings of the ground warp 11 and the selvedge warp 12 formed by the heald frame for the ground warp and selvedge warp (not shown). Although not shown, the sleigh 10 is usually provided with a large number of known weft guide members and an appropriate number of auxiliary air nozzles in parallel with the reed 9.

In such a shuttleless loom, the tensioner 2 includes a washer tenser as shown in FIG. 1 and an air tensor as shown in FIG. The weft yarn is always held between the washer 2b, and tension is always applied to the weft yarn drawn out from the yarn feeding section 1 by the feed roller 3a of the length measuring device 3.
In addition, in the air tensor, as shown in Figure 2, compressed air from an air source (not shown) is supplied to the regulating valve 2.
By constantly injecting compressed air from the air nozzle 2d in the direction of the yarn feeding section 1 through the air nozzle 2d, tension is constantly applied to the weft yarn pulled out from the yarn feeding section 1 by the feed roller 3a. Granted.

In this way, with conventional tensors, tension is always applied to the weft yarns, so in the case of washer tensers, there are problems in that the weft yarns are damaged and the washer wears out prematurely. In this case, there was a problem in that a large amount of compressed air was consumed.

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide a weft tensioning method that solves the problems of the prior art mentioned above.

Structure of the Invention According to the research of the present inventor, as mentioned above, the conventional tensioner conventionally applies tension to the weft at all times, but the purpose of installing the tensioner is to This is to prevent the weft threads from being unwound too much toward the length measuring device due to inertia, especially in the case of thick threads, and from getting tangled without being guided to the designated part of the length measuring device. It turns out that the tensor function is not necessary.

Further, according to research by the inventor of the present application, while the loom is stopped, the weft from the yarn feeding section may be loosened to some extent by its own weight. Therefore, even if tension is applied to the weft yarn by the tensor during stopping to prevent overrun of the weft yarn, that is, loosening on the weft length measuring device due to over-feeding, the weft yarn between the yarn feeding section and the tensor is is affected by the above-mentioned overrun and may become loose due to its own weight. Therefore, if the loom is started with such slackness present, the slackness will remain and it will be difficult to apply appropriate tension to the weft yarns.

Based on this knowledge, in order to achieve the above-mentioned purpose, the weft tension applying method according to the present invention operates the tensioner from before the machine starts to a predetermined time after the machine starts, and then disables it. In this case, the tensioner is operated from a predetermined time point before stopping until after stopping, and when the tenser is operated, tension is applied to the weft yarn to the weft length measuring device.

Embodiment 1 FIG. 3 shows a schematic block diagram of an apparatus for implementing the first embodiment of the present invention (implemented in an air tensor), and the apparatus is operated according to the flowchart of FIG. 4. As a result, as shown in FIG. 5, the air tensioner is operated to apply tension to the weft yarn.

That is, in FIG. 3, a solenoid valve 21 is interposed between the air tensor 2 and the air source 20,
The solenoid valve 21 is controlled by a control device 22 such as a microcomputer. The control device 22 has an arithmetic processing unit 23 and a driver 24, and the arithmetic processing unit 23 includes a stop signal from a sensor 25 that detects machine stop conditions due to selvage thread, discarded selvage, warp thread, weft thread breakage, human operation, etc. A request signal is input. Further, an activation signal from a switch button 26 for operating the machine base motor is input to the arithmetic processing section.

In FIG. 3 and FIG. 4, when starting, first, the power is turned on and the output signal of the arithmetic processing unit 23 drives the driver 24, and the output signal of the driver 24 drives the solenoid valve 21. Turns on and opens. Therefore, compressed air from the air source 20 is supplied to the air nozzle 2d of the tensor 2,
The tensor 2 is in an operating state in which compressed air is injected from the air nozzle 2d to apply tension to the weft.
Thereafter, when the switch button 26 of the machine base motor is pressed, the motor is turned on and the machine base rotates. On the other hand, the activation signal from the switch button 26 is also supplied to the arithmetic processing unit 23, and the arithmetic processing unit 23 measures a predetermined time from the time when the activation signal is input using a timer, and when the timer reaches the indicated value, the arithmetic processing unit 23 The output signal of 23 is the driver 24
The solenoid valve 21 is closed by the output signal of the driver 24, and the tensor 2 becomes inoperable.

In this state, the machine continues normal operation, during which time the tensor 2 is inactive and does not apply unnecessary tension to the weft. During this normal operation, when the sensor 25 generates a machine stop request signal and inputs it to the arithmetic processing unit 23, the arithmetic processing unit 23 drives the driver 24,
The solenoid valve 21 is activated by the output signal of the driver 24.
Open it and put Tencer 2 into operation. On the other hand, the arithmetic processing unit 23 detects the crank angle of the machine base, and when a predetermined angle suitable for stopping the machine base is detected, the motor is turned off and a brake (not shown) is turned on to stop the machine base.

If the power is not turned off, the machine will stop with Tencer 2 operating.

Next, when you turn on the switch button to restart, the machine will restart according to the procedure described for startup.

Although the time from when the machine starts to start until the tensor 2 finishes operating is controlled by a timer, it may also be controlled by the crank angle.

Therefore, according to the first embodiment of the present invention, as can be understood from FIG. 5, during startup (including restart), the tensor is operated from before startup to a predetermined point after startup, and then is turned off. When the machine is activated and the machine is stopped,
The tensor is operated from a predetermined time before stopping until after stopping, and the tenser does not always apply tension to the weft.

Embodiment 2 FIG. 6 is a diagram corresponding to FIG. 3 when the present invention is applied to a washer tensor, and the main difference is that the tensor 2 has a spring 2a and a washer 2b.
This second embodiment is substantially the same as the first embodiment described above, in that it is of the washer type and that a solenoid 27 is used instead of the solenoid valve 21 to drive the tensor. act.

Effects of the Invention As described above, according to the present invention, since the tensor does not operate all the time, tension is not constantly applied to the weft. Therefore, in the case of an air tensioner, the amount of air consumed is greatly reduced and energy is saved, and in the case of a washer tensioner, the weft yarns are not damaged, and the durability of the tensioner is increased. Considering the problem of loosening of the weft between the yarn feeder and the tensor when the loom is stopped, the tensioner is operated for a predetermined period before and after the loom is started, so that the weft that loosens during the stop is removed during this predetermined period. Tension is applied inside by a tensor to remove looseness,
It is supplied to the weft length measuring device. Therefore, the slack can be removed and appropriate tension can be applied to the weft. Furthermore, if a microcomputer is used to control the tensor, the sensor activation timing and activation time can be easily adjusted using software.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing an example of a shuttleless loom in which the present invention can be implemented, FIG. 2 is a schematic plan view of a shuttleless loom with a different tensor type from that in FIG.
The figure is a schematic block diagram of an apparatus for implementing the first embodiment of the present invention, and FIG. 4 is a flowchart for implementing the first embodiment of the present invention in the apparatus of FIG.
Fig. 5 is a diagram showing the operation timing of the machine base and tensor etc. in the first embodiment, and Fig. 6 is a diagram showing the operation timing of the machine base and tensor etc.
1 is a schematic block diagram of an apparatus for carrying out an embodiment; FIG. In the figure, 1 is a yarn feeding section, 2 is a tensor, 3 is a weft measuring device, 21 is a solenoid valve, 22 is a control device, 25 is a tensor, and 27 is a solenoid.

Claims (1)

[Claims] 1. In a shuttleless loom that has a tensor between the yarn feeding section and the weft length measuring device, when starting, the tenser is activated from before startup to a predetermined point after startup, and then is deactivated, and when the loom is stopped, . A weft tension applying method, which operates the tenser from a predetermined time before stopping until after stopping, and applies tension to the weft to the weft length measuring device when the tenser is activated.