JPH0467Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a weft length measuring device for a fragmentary loom.
In particular, it relates to a drive means for a yarn guide in a drum-type weft length measuring device.

A drum-type weft yarn length measuring device measures and stores the length of one pick of weft yarn by winding the weft yarn around a length measuring drum.

In conventional devices of this type, the rotational force of the thread guide is derived from the rotation of the main shaft of the loom. For this reason, the rotational force transmission system is complex and occupies a large space. Further, the rotation of the thread guide is always synchronized with the rotation of the loom, but its rotational speed is always constant and cannot be changed during operation. Therefore, for example, 2 of "2 x 1"
In alternating color weaving, etc., the periods of weft insertion are not equal, so it is necessary to temporarily lock the weft threads after length measurement. Such a temporary locking means is shown in, for example, Japanese Patent Laid-Open No. 79740/1983. In the invention disclosed in the publication, a blocking mechanism is provided on the outer periphery of the drum, and the weft thread after release is moored by a blocking pin until the next weft thread is inserted.
However, such a blocking mechanism is not practical because it requires complicated synchronization control, and cannot flexibly respond to changes in weaving.

Therefore, an object of the present invention is to separate the drive system of the weft length measuring device from the drive system of the loom, and to enable its rotation speed to be freely controlled in accordance with changes in the weaving method.

Based on the above object, the present invention disposes a drive motor on the axis of the length measuring drum, attaches a thread guide to the rotor shaft of this drive motor, or forms the rotor shaft and thread guide integrally, This simplifies the drive system for the yarn guide, and allows the number and speed of rotation of the yarn guide to be controlled separately from the rotation of the loom.

Hereinafter, the structure and operation of the present invention will be specifically explained based on an embodiment shown in the drawings.

First, FIG. 1 shows a weft length measuring device 1 of the present invention. The weft thread length measuring device 1 includes a length measuring drum 2, a drive motor 3, and a thread guide 4 as main parts.

The length measuring drum 2 is connected to the rotor shaft 5 by a bearing 6 at the tip of the rotor shaft 5 of the drive motor 3.
The outer peripheral surface of the weft thread 7 forms a winding surface 8 for the weft thread 7.
Note that a drive pin 9 is provided in the hole 8a of the winding surface 8 so as to be movable forward and backward.

Further, the drive motor 3 is, for example, a DC servo motor, and its stator 3a is fixed to a mounting portion 10 such as a frame. The rotor shaft 5 is press-fitted into the center of the rotor 3b of the drive motor 3, and is rotatably supported by a bearing 11 of the casing 3c.
The thread guide 4 is attached to the tip of the rotor shaft 5 at a predetermined angle of inclination.
It rotates together with the rotor 3b, and its tip can rotate along the outer periphery of the length-measuring drum 2, which is in a stationary state. The thread guide 4 and the rotor shaft 5 form a guide hole 12 along the axial direction, and the weft thread 7 passes from the open end of the rotor shaft 5 through the guide hole 12 to reach the tip of the thread guide 4.
There, it is guided outside and wound around the outer periphery of the winding surface 8 of the length measuring drum 2. Further, the rotor shaft 5 fixedly supports a radial arm 13, and this arm 13 rotatably supports an intermediate shaft 14 by means of a bearing 15. This intermediate shaft 14 has timing pulleys 16 and 17 fixed at each end, and timing belts 18 and 19 wound around these timing pulleys 16 and 17 are connected to timing pulleys fixed to a casing 3c, etc., respectively. 20 and a timing pulley 21 attached to the length measuring drum 2
are wrapped around each. Note that a rotating plate 22 is attached to the end of the rotor shaft 5, and a rotation sensor 23 corresponds to this rotating plate 22.

Next, FIG. 2 shows a control circuit 24 for the drive motor 3. As shown in FIG. This control circuit 24 detects the amount of rotation of the main shaft 25 of the loom as a number of pulses using a rotation detector 26, converts this signal into the amount of rotation of the drive motor 3 as a command value, and thereby controls the rotational motion. Control. The amount of rotation of the drive motor 3 is detected as the number of pulses by the rotation sensor 23 and sent to the control circuit 24 as a feedback signal.

Next, the operation of the weft length measuring device 1 will be explained.

The control circuit 24 stores a speed pattern in advance, and depending on the amount of rotation of the main shaft 25, controls the drive motor 3 using a digital servo system as shown in the prior art in the specification of JP-A No. 59-30941. Give a rotation command to. Therefore, the rotor 3b of the drive motor 3 applies a rotational movement to the yarn guide 4 and the rotor shaft 5 by an amount of rotation corresponding to the amount of rotation of the main shaft 25 based on the contents of the given command. In this way, the rotation of the drive motor 3 is always synchronized with the rotation of the main shaft 25, and the amount of rotation follows the amount of rotation of the main shaft 25 in proportion to the amount of rotation. At this time, the arm 13 rotates together with the rotor shaft 5, but since the timing pulleys 20 and 21 are fixed,
The length measuring drum 3 remains stationary only by allowing the rotor shaft 5 to rotate. On the other hand, during length measurement, the drive pin 9 is inserted into the hole 8a of the winding surface 8 of the length measuring drum 2.
Since the weft thread 7 faces the drive pin 9, the weft thread 7 is stopped by the drive pin 9, and as the thread guide 4 rotates, the weft thread 7 is sequentially wound around the outer periphery of the winding surface 8 by the required length. The winding length of the weft thread 7 at this time, that is, the length for one pick can be detected from the amount of rotation of the rotor shaft 5 of the drive motor 3. For this detection, the rotation sensor 23 continuously generates a pulse signal with a number of pulses proportional to the amount of rotation of the rotor shaft 5, and sends it to the control circuit 27 as a feedback amount.

When the drive motor 3 follows the rotation of the main shaft 25 and rotates by an amount corresponding to the rotation amount command value,
Based on the deviation between both input signals, the control circuit 24
stops the rotation of the rotor shaft 5. In this way, a length of weft yarn 7 corresponding to one pick is accumulated on the circumferential surface of the winding surface 8.

When the weft insertion time comes, the drive pin 9 retreats and releases the stored weft thread 7, so the weft insertion nozzle etc.
is made to fly along the length of the warp threads along with a jet of fluid. In this way, the weft yarn length measuring device 1 measures the length of the weft yarn 7 for one pick and stores it in accordance with the timing of weft insertion.

In addition, in the above embodiment, a winding device is used as a means for keeping the length measuring drum 2 still, but the stopping means may be achieved by attaching a weight to an eccentric position of the length measuring drum 2 or by magnetic attraction. It may be a structure that is restrained by force. Further, the rotor shaft 5 and the thread guide 4 may be integrally formed with a cylindrical body.

The present invention provides the following effects.

First, since the rotor shaft of the drive motor is directly connected to or integrated with the thread guide, no complicated rotation transmission mechanism is required.

In addition, the amount of rotation of the drive motor always follows the amount of rotation of the main shaft of the loom, and the rotation speed can be electrically increased or decreased electrically on the control circuit side. Even if the weft length (length and storage time) changes periodically, the length measurement of the weft can be set in accordance with the timing of weft insertion, independent of the rotation of the main shaft of the loom.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of the weft length measuring device of the present invention, and FIG. 2 is a control circuit diagram of the drive motor. 1... Weft length measuring device, 2... Length measuring drum, 3
... Drive motor, 4 ... Thread guide, 5 ... Rotor shaft, 7 ... Weft thread, 24 ... Control circuit.

Claims (1)

[Claims for Utility Model Registration] A drive motor 3 is arranged on the axis of the length measuring drum 2 in a stationary state, and a thread guide 4 is attached to the rotor shaft 5 of the drive motor 3 so that it can freely rotate around the length measuring drum 2. A weft length measuring device 1 is attached to the rotor shaft 5 and the yarn guide 4, and has a guide hole 12 formed on the axis of the rotor shaft 5 and the yarn guide 4, and guides the weft yarn 7 from the drive motor 3 side toward the length measuring drum 2 through the guide hole 12.
The digital servo system includes a rotation detector 26 that generates a pulse signal with a number of pulses proportional to the amount of rotation of the main shaft 25 of the loom, and a rotation detector 26 that generates a pulse signal with a number of pulses proportional to the amount of rotation of the drive motor 3. The pulse signals from the sensor 23 and the rotation detector 26 are input as the rotation amount command value, and the pulse signal from the rotation sensor 23 is input as the feedback amount, and the rotation of the drive motor 3 is controlled based on both input pulse signals. A weft length measuring device 1 characterized by comprising a control circuit 24 that controls the amount to follow the rotation amount of a main shaft 25.