JPH0210251B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for actively feeding warp threads of a loom.

This type of feeding device is provided to feed out a necessary amount of warp threads in accordance with the winding of the woven fabric, and to always set the tension of the warp threads at a desired value.

Warp tension control in conventional delivery devices is generally performed by detecting warp tension using a tension detection roll and controlling the rotational speed of a delivery beam. Although this conventional control means can effectively cope with changes in the winding diameter of the sending beam, fine tension control during one revolution of the loom is almost impossible.

Therefore, an object of the present invention is to finely control the tension of the warp threads during one revolution of the loom, that is, during one cycle of each movement, to prevent the warp threads from becoming entangled, increase the operating rate of the loom, and to prevent The purpose is to bring out the bulge in the warp threads and the texture of the fabric.

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

First, FIG. 1 shows an example of a crank circle of a loom. The loom performs one cycle of movement as the rotation angle θ ranges from 0 degrees to 360 degrees. The start of opening, start of flight, maximum opening and end of flight are as follows:
They correspond to rotation angles θ ₁ , θ ₂ , θ ₃ , and θ ₄ , respectively.

Next, FIG. 2 shows the ideal warp tension T during one rotation of the loom in relation to the rotation angle θ. This curve of warp tension T is based on increasing the tension at the time of shedding, improving thread handling, eliminating entanglement of warp threads by the time the weft insertion begins, and maintaining a certain level of tension during the weft insertion period. The goal is to smoothly insert the weft, and then lower the tension when the weft insertion is complete so that the warp threads intersect with each other in a sufficiently swollen state when inserting the weft threads, giving the texture of the fabric. When such a warp tension T is set as a control target, the motor current i of the feed-out motor must change in a step manner in the same way as the warp tension T changes. It should be noted that the opening amount L of the warp threads changes in a chevron shape, as shown in the figure.

The present invention enables ideal control as described above, and FIG. 3 shows an electric weaving machine 1 according to the present invention. Warp 2
The fabric passes from the delivery beam 3 to the guide roll 4, becomes the woven fabric 6 at the weaving edge 5, passes through the roll 7, the winding roll 8, and the roll 9, and is wound onto the winding beam 10. During this time, the warp yarns 2 perform a shedding motion by the healds 11. A drive motor 12 of the loom drives the winding roll 8 in the winding direction at a constant rotational speed via a gear 13. Further, the feed motor 14 forcibly drives the feed beam 3 in the direction in which the warp threads 2 are fed through the gear 15 . The feed motor 14 is a variable speed DC motor, and rotates with a current setting signal Vi given by a tension setting device 16 as input.
That is, the tension setting device 16 has a plurality of, for example, four tension setting devices 16 ₁ , 16 ₂ , 16 3 , 16 ₄ , and the tension setting device 16 has four tension setting devices 16 1 , 16 ₂ , 16 3 , 16 4 corresponding to the target tension value required during one cycle of the loom. A specific current setting signal Vi is generated. Current setting signal for one of them
Vi is selected by the gate function of the selection device 17 and provided to the amplifier 19 from the summing point 18 . Here, the amplifier 19 generates a motor current i corresponding to the current setting signal Vi, and the output motor 14
supply to. Note that the current detector 20 is connected to the amplifier 1
The output of 9, that is, the motor current i is detected, and this is negatively fed back to the summing point ₁₈ as a current feedback signal if.

On the other hand, an encoder 21 ₁ serving as a timing detection device 21 is mechanically coupled to the drive motor 12 . This encoder 21 ₁ is connected to, for example, a crankshaft of a loom, and detects the rotation angle θ during one rotation, that is, the timing of each movement, generates a timing signal _ST , and sends this to the selection device 17. There is. Here, the selection device 17 selects a current setting signal Vi having a value corresponding to the timing from the tension setting device 16, and applies the current setting signal Vi corresponding to each timing to the addition point 18. In this way, the motor current i of the delivery motor 14
are sequentially switched to motor currents i ₁ , i ₂ , and i ₃ corresponding to the timing during one rotation of the loom. As a result, the warp tension T approaches approximately the target tension shown in FIG.

Note that the sending beam 3 is equipped with a winding diameter detector 22.
is attached. This winding diameter detector 22 detects the winding diameter of the warp threads 2 of the sending beam 3, and controls the voltage of the field winding 23 of the sending motor 14 using a winding diameter signal V _R proportional to this. As a result, even if the winding diameter changes, the feed motor 14 generates the necessary torque. Of course, this winding diameter detector 22
may not act on the field winding 23 but may act directly on the motor current i of the sending motor 14. In the case of rotor current control, it is necessary to automatically adjust the value of the current setting signal Vi of the tension setting device 16, so special switching control is required.

Further, the guide roll 4 is provided with a tension detector 24 . The tension detector 24 indirectly measures the warp tension T by detecting the bearing load of the guide roll 4 with a load cell or the like, and sends this as a tension feedback signal Tf from the summing point 25 to the tension control amplifier 26. Further, the tension setting device 16 applies a tension setting signal V _T corresponding to each timing to the addition point 25 via the selection device 17. Therefore, the tension control amplifier 26 compares the tension setting signal V _T and the tension feedback signal Tf,
An output signal is applied to the addition point 18 according to the difference. In this way, the feed motor 14 has current feedback system control and tension feedback system control, and performs tension control with high accuracy.

On the other hand, an inertia correction calculation device 27 is attached to this electric feeding device 1. This inertia correction calculation device 27 receives the winding diameter signal V _R and the timing signal S _T as input, and generates an inertia correction signal V _I corresponding to the inertial rotational force of the sending beam 3 and other rotating bodies at each timing. , is applied to the addition point 18 with a plus or minus sign. The reason for this is that, as shown by the two-dot chain line in Fig. 2, the direction of the shedding movement of the warp threads 2 suddenly changes at an intermediate rotation angle θ3 (180 degrees), so that the warp tension T decreases to the target value during shedding. The warp tension T tends to become higher, and conversely, during the closing movement, the warp tension T tends to become lower.
As shown by the solid line in the figure, the rotation angle θ2~θ4 (90~
This is to keep the warp tension T constant between 270 degrees and 270 degrees. Therefore, in the present invention, the inertia correction calculation device 27 calculates the warp tension T during the two movements.
In order to eliminate the difference in tension, a tension deviation ΔT is stored in advance to make a difference in the input to the feed motor 14, and a negative inertia correction signal V _I is stored while the opening is progressing.
, and conversely, a positive inertia correction signal V _I is sent to the summing point 18 during the closing process. As a result, fluctuations in the tension during the opening movement are reduced, held approximately constant, and corrected to a value close to the target value. It should be noted that temporary tension fluctuations occur during reshaping, but even if this fluctuation is a stable tension change, the inertia correction calculation device 27 generates the inertia correction signal _VI necessary for the correction. These correction amounts may be experimentally measured in advance for each loom, and values corresponding to the measured values may be set as coefficients in the coefficient unit of the inertia correction calculation device 27. By the above correction, tension control during one rotation of the loom can be realized with high accuracy.

Next, other embodiments of the present invention will be described.

First, in the embodiment shown in FIG. 4, the timing of the loom is not detected from its rotation angle θ, but the movement of the delivery beam 3 or guide roll 4 during shedding movement is detected by the tachometer generator 21 ₂ as the timing detection device 21. And this timing signal S _T
selectively drives the switching element of the selection device 17 either directly or by differentiating the
This is an example of tension control by selecting an appropriate current setting signal Vi. When the loom passes the rotation angle θ ₁ , the shedding movement begins, the warp tension T increases, and the sending beam 3 and guide roll 4 rotate due to the increased tension. At this time, since the tachogenerator 21 ₂ rotates in conjunction with it, a voltage is generated as the timing signal _ST . This voltage is connected to the regulating resistor 28 and the priority diode 29 of the selection device 17.
The signal is input to the differentiator 30 through the . Since the positive differential signal of the differentiator 30 is in the forward direction with respect to the forward/reverse switching diode 31, it passes through it and is applied to the tension setting device 1.
₆ , the current setting signal Vi becomes a positive current setting signal Vi, and is applied to the addition point 18. In this way, the motor current i ₁ is set. As the aperture progresses further, the timing signal S _T of the tachogenerator 21 ₂ changes to the power supply 32 and the gain setting device 16 _{5 .}
The set voltage is reached, and current flows through the resistor 28 and diode 33. At this time, differentiator 3
Since the input of 0 is eliminated, the motor current _i2 is set by the current setting signal Vi of the tension setting device ₁₆₇ . In this case, the tension increases due to the inertia of the delivery beam 3 until the shedding reaches its maximum value, and when the shedding exceeds the maximum value, the delivery beam 3 rotates in the reverse direction and the warp tension T decreases. The tension fluctuation at this time can be compensated for by the inertia correction calculation device 27 described above. Furthermore, as the opening approaches the end,
The differentiator 30 starts operating again, and the motor current _i3 is set through the forward/reverse switching diode 34 and the gain setter ₁₆₈ . In this way, the current setting signal Vi is generated in synchronization with the tension fluctuations of the warp threads 2 during one cycle of the loom.

Next, the embodiment shown in FIG.
1 ₂ to the delivery motor 14, and
The servo motor 3 is activated by the winding diameter signal V _R of the winding diameter detector 22.
5, and its rotational force drives variable resistors 36,
37 to adjust the signal level in accordance with the winding diameter. The variable resistor 36 adjusts the level of the timing signal _ST , and the variable resistor 37 adjusts the voltage of the tension setting device ₁₆₇ . In this way, winding diameter compensation and tension compensation are performed simultaneously. Other operations are similar to those in FIG. 4.

Note that the function of the tachometer generator ₂₁₂ can be replaced by a timing lever and a proximity switch. The timing lever detects tension fluctuations in the warp threads 2 as changes in lever angle, and changes the distance from the proximity switch. At this time, the proximity switch has
A timing signal _ST corresponding to the tension fluctuation is generated. Furthermore, the above-mentioned inertia correction calculation device 27 may operate all the time, but may operate only when a large deviation occurs. In this case, the allowable deviation is stored at each timing during one cycle of the loom, and the inertia correction calculation device 27 starts the correction operation only when the actual deviation ΔT is larger than the allowable deviation. The comparison, calculation, storage functions, and a series of control functions at this time can be easily realized using a CPU or a control computer.

The present invention provides the following unique effects. Since tension control is performed at each timing during one revolution of the loom, fine tension control is possible in correspondence with the movement of the loom. Also, when the loom moves, the rotational energy of the feed beam etc. causes fluctuations in the target tension, but the inertia correction calculation device calculates the tension fluctuations and makes the necessary corrections, so the shedding movement of the loom and the Fluctuations in target tension due to striking motion are effectively corrected. These functions are effective in preventing warp threads from becoming entangled and increasing the operating rate of the loom, as well as in creating an appropriate bulge in the warp threads and giving the fabric its texture.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a crank circle, FIG. 2 is a graph of warp tension, motor current, and shedding amount corresponding to the rotation angle of the loom, and FIG. 3 is a block diagram of the electric feeding device of the loom according to the present invention. 4 and 5 are block diagrams of other embodiments of the same device. 1...Electric sending device of the loom, 2...Warp,
3... Delivery beam, 14... Delivery motor, 16... Tension setting device, 17... Selection device,
21...timing detection device, 21 ₁ ...encoder, 21 ₂ ...tachogenerator, 27...inertia correction calculation device.

Claims (1)

[Scope of Claims] 1. A timing detection device that detects the timing of movement of a loom and generates a timing signal, a variable speed feed-out motor that drives a feed beam to actively send out warp yarns, and a loom for the warp yarns. a tension setting device that sets a current setting signal to the sending motor corresponding to a target tension value at each timing of the movement; and a current setting signal corresponding to the timing signal from the tension setting device when the timing signal of the timing detection device is input. and a selection device that selectively supplies a corresponding current setting signal of the tension setting device to the sending motor in accordance with a timing signal of the timing detection device. Electric feeding device. 2. The electric weaving device for a loom according to claim 1, wherein the timing detection device is constituted by means for detecting the rotation angle of the loom and generating a timing signal in synchronization with one revolution of the loom. 3. The electric feeding device for a loom according to claim 1, characterized in that the timing detection device is constituted by means for detecting tension fluctuations in the warp threads and generating a timing signal in correspondence with the movement of the loom. 4. A timing detection device that detects the timing of the movement of the loom and generates a timing signal, a variable speed feed-out motor that drives the feed beam to actively send out the warp threads, and a timing detection device that detects the timing of the movement of the loom and generates a timing signal; a tension setting device that sets a current setting signal to the sending motor corresponding to a target tension value; and a tension setting device that provides a current setting signal corresponding to the timing signal from the tension setting device when the timing signal of the timing detection device is input. , a selection device that selectively supplies a corresponding current setting signal of the tension setting device to the delivery motor in accordance with a timing signal of the timing detection device; and a selection device that detects a winding diameter of the delivery beam and outputs a winding diameter signal. a winding diameter detector, a winding diameter signal from this winding diameter detector, and a timing signal from the timing detector are input, and an inertia correction signal corresponding to the inertial rotational force at each timing is given to the delivery motor. An electric feeding device for a loom, characterized by comprising: