JPH02175950A - Weft-length measuring apparatus for fragment loom - Google Patents

Abstract

PURPOSE:To prevent defective weft insertion without applying a load to a nozzle and, accordingly, without increasing the capacity of a pump system by measuring the length of a weft with a length-measuring roller synchronous to the flying of weft with a fluid nozzle and forcedly introducing the weft to the nozzle. CONSTITUTION:A length-measuring roller 15 is placed in a weft channel between a weft bobbin 14 and a fluid nozzle 13 and the roller 15 is provided with its driving motor 17 and a drive-control circuit 18. The driving motor 17 is energized synchronous to the start of the ejection of the fluid nozzle 13 to rotate the length-measuring roller 15 by specific revolutions to pull out a weft 18 from the weft bobbin 14 at a length corresponding to the rotational number. The pulled weft 8 is flown toward the warp opening part by the fluid nozzle 13.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a weft lengthening device in a fragmentary loom.

(Prior Art) In a fragmentary loom, a weft fed into a warp opening is measured and cut. In FIG. 5, the warp threads 2 wound around the yarn beam 1 are passed through an opening 7 between the guide rollers 3 and 4 by belt frames 5 and 6 (only two are shown).
is formed. The weft yarn 8 is inserted into this opening.

The inserted weft yarn is then driven in by the reed 9. The woven fabric formed by weft insertion is wound up on a take-up roller IO. The reed 9 is swingable between a retracted position shown by a solid line and a driven position shown by a chain line, and is swung by receiving power from a drive source 11 via a crank mechanism or a cam mechanism. The weft yarn 8 is as shown in FIG.

The length is measured by a length measuring device 12, and the length is flown to the warp opening by a fluid nozzle, for example, a water jet nozzle 13.

As length measuring machines, several methods have been proposed and put into practical use, such as a drum length measuring method and a pool pipe length measuring method. In the drum length measuring method, the length of the weft to be inserted is set by winding the weft, which is easily unwound and wound around the bobbin of the weft supply mechanism, by a predetermined length onto a length measuring drum having a tapered peripheral surface. The pool pipe length measurement method measures the length of a weft thread wound around a bobbin by pulling it into the pipe using a vacuum.

(Problems to be Solved by the Invention) The drum length measurement method described above requires a baffle plate to prevent the so-called ballooning phenomenon in which the weft yarn unwound from the length measurement drum spreads in the radial direction when the weft yarn is made to fly with the jet nozzle. Therefore, there is a problem in that the friction between the baffle plate and the weft puts a large load on the jet nozzle. This interlayer causes incomplete flight of the weft yarn, leading to a high load on the jet nozzle and the pump system that drives it. In addition, with the pool pipe length measurement method mentioned above, the vacuum pressure during length measurement becomes a load on the jet nozzle, so the flight capacity must be significantly increased, and the increased capacity of the pump system increases bulk and noise. There is also the problem that it also gets larger.

An object of the present invention is to provide a weft length measuring device for a fragmentary loom that can measure a length of 8 without particularly improving the flying ability of the nozzle and without causing heavy snowfall on the device.

(Means for Solving Problem 31) The length measuring device of the present invention is rotatably disposed in a weft passage between a fluid nozzle and a weft supply mechanism, and measures a length of a weft wound around the weft at least once. a long roller; a drive motor that rotates the length measuring roller in order to unwind a predetermined length of weft from the weft supply mechanism; and a drive motor that operates in synchronization with the flight of the weft to rotate the length measuring roller a predetermined number of times. The invention is characterized by comprising a control device for controlling the

(Function) When the weft opening is formed and the timing for weft flight is reached, the control device drives the drive motor to rotate the length measuring roller a predetermined number of times to let out the weft from the weft supply mechanism.

The drawn-out weft yarn is inserted into the warp opening by a fluid nozzle. When the weft yarn is driven in by the reed, the cutter is activated to cut the weft yarn.

(Example) The present invention will be described in detail below based on an example shown in the drawings. In FIG. 1, a length measuring roller 15 is provided in the weft passage between the fluid nozzle 13 and the bobbin 14 as a weft supply mechanism.
is rotatably arranged. The bobbin 14 is wound with a weft drawn from a barn, a cone, etc. in such a manner that it can be easily unwound. The length measuring roller 15 is a roller made of a hard material plated with chrome, for example, and a weft thread 8 is wound at least once around the outer periphery of the roller as shown in FIG. A pinch roller 16 made of an elastic material is elastically brought into contact with the outer peripheral surface of the length measuring roller 15 so that the weft and the length measuring roller 15 do not slip in the transfer direction. The length measuring roller 15 is driven by a drive motor 17. The rotation of this drive motor 17 is controlled by a drive motor control circuit 18. This circuit 1
8 is controlled by a control signal from a control device 19 that controls the entire loom main body. The operation of the nozzle is controlled by a nozzle control circuit 20 that is controlled by a signal from a control device W119.

Note that the nozzle control circuit 20 and the drive motor control circuit 18 may be mechanisms that are mechanically operated by signals output from the control device 19. The weft may have a flange for preventing the weft from coming off.

The operation of the embodiment configured as above will be explained. Fourth
The figure shows the timing of weft insertion and driving, and when the motor 11 of the loom main body is turned on, the main shaft 11a
(see FIG. 5) is constantly rotated, causing the reed 9 to swing. The reed 9 has one driving position per rotation of the main shaft 11a, and the main shaft angle is 65', 425°, and 785°.
position). As the main shaft rotates, the warp yarns alternate between upper and lower yarns to form an opening 7.

The nozzle 13 is turned on when the warp threads 2 form an opening, and starts spraying to make the weft threads 8 fly. At this time, the drive motor 17 that rotationally drives the length measuring roller 15 is turned on, and the roller 15 is rotated a predetermined number of times. When the length measuring roller 15 rotates, the weft 8 wound around it is unwound from the bobbin 14 by a length corresponding to the number of rotations of the roller 15.

This unwound weft yarn 8 is made to fly toward the opening 7 (see FIG. 5) by the nozzle 13 that has started jetting. The length measuring operation by the length measuring roller 15 is temporarily stopped when the drive motor 17 is stopped. The length measuring operation, that is, the rotational drive of the length measuring roller is stopped at the same time as or slightly before the nozzle 13 stops ejecting. After the reed 9 drives the weft fed into the opening 7, the cutter 21 (
(see FIG. 5) is activated to cut the weft yarn 8. Thereafter, the length measuring roller 15 is driven to rotate in synchronization with the rotation of the main shaft, that is, with the timing of weft flight, and measures the length of the weft. Here, the timing of the start of jetting from the nozzle 13 and the start of rotation of the length measuring roller 15 will be explained in a little more detail.

If the motor is driven earlier than the nozzle starts jetting, the length measuring roller will start feeding the yarn immediately, and the length measuring roller 15 will start feeding the yarn.
There is a fear that the weft yarn may become loose between the nozzle 13 and the nozzle 13.

However, in reality, after turning on the drive motor 17,
Since there is a time lag until the length measuring roller 15 starts rotating, the actual length measuring start time is slightly to the right of the position shown in FIG.

The length measured by the length measuring roller 15 is appropriately set by controlling the rotation angle of the roller with the rotation angle of the drive motor 17 according to the length of the weft depending on the width of the woven fabric. In addition, in the weft passage between the bobbin 14 and the nozzle 13,
Of course, weft clippers may be provided before and after the length measuring roller 15. Although a ballooning phenomenon occurs in the weft yarn between the clipper and the bobbin 14, this phenomenon does not become a load on the nozzle 13 because the weft yarn is forcibly conveyed by the length measuring roller 15.

FIG. 3 shows another example of controlling the rotation of the length measuring roller 15. A clutch 22 is provided in the rotation transmission system between the constantly rotating drive motor 17 and the length measuring roller 15, and this clutch is activated by a clutch control circuit 23 in synchronization with the weft flight to drive the roller 15 to rotate and measure the length. . It is also possible to use the driving force of the motor 11 (see FIG. 5) of the main body in place of the driving motor 17. According to such a configuration,
Since the rotation of the length measuring roller 15 starts up quickly, the timing of starting length measurement and the timing of starting nozzle jetting can be completely synchronized. The rotation speed of the length-measuring roller 15 may be detected to detect the length to be measured, and the driving of the roller may be controlled.

(Effects of the Invention) As described above, according to the weft length measuring device of the present invention, by rotating the length measuring roller around which the weft is wound, the length of the weft is measured and the weft is forced toward the nozzle. Since the length measuring operation does not place a load on the nozzle that sends the weft flying, this completely eliminates the problems of insufficient weft insertion and increased capacity of the pump system.

[Brief explanation of the drawing]

Fig. 1 is a front view of a weft length measuring device for a fragmentary loom showing an embodiment of the present invention, Fig. 2 is a perspective view showing a length measuring roller, and Fig. 3 is another example of means for driving the length measuring roller. FIG. 4 is a timing chart showing the operation of the weft length measuring device of the present invention, FIG. 5 is a front view showing an overview of the fragment loom, and FIG. 6 is a plan view of the main parts of the same. 2... Warp, 7... Opening, 8-... Weft, 13...
... Fluid nozzle, 15... Length measuring roller, 17... Drive motor, 18... Drive motor control circuit, 19...
Control device. vine D mouth G encirclement

Claims (1)

[Scope of Claims] A fragmentary loom in which a weft measured to a predetermined length is sent between warp threads in which openings are formed by a fluid nozzle and driven in with a reed, wherein: a length-measuring roller rotatably disposed in the weft passage and around which the weft is wound at least once; and a drive motor that rotates the length-measuring roller in order to feed out a predetermined length of weft from the weft supply mechanism. and a control device that operates the drive motor in synchronization with weft flight to rotate the length measuring roller a predetermined number of times.