JPH0360941B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a soft start method for strengthening the beating force at the initial stage of starting up a loom to prevent the occurrence of weaving steps.

[Conventional technology]

When the loom is started, its rotational speed (angular velocity) does not reach a steady rotational speed immediately, but reaches a steady value only after the main movement has been repeated several times.

When the rotational speed is lower than the steady state, the beating force becomes weaker, and weaving steps are more likely to occur in the woven fabric.

Therefore, in order to prevent the occurrence of this weaving step,
A method has been adopted in which an induction motor for driving a loom with a large starting torque is used to rapidly accelerate the loom to a steady rotational speed within one rotation when starting the loom.

[Problems with conventional technology]

However, according to the sudden acceleration start mentioned above,
It has the following drawbacks.

A large rotational force acts on the loom's rotational drive system in the early stages of startup, and its acceleration changes rapidly in a short period of time, which requires more rigidity and durability than necessary for the rotational drive system, making the loom expensive. Become.

When the loom is started, the starting torque of the induction motor for driving the loom always acts in a direction that overcomes the load of the loom with a margin, so the reel bends greatly in the longitudinal direction and the radial direction of the loom. The amount of deflection changes each time it is activated. Therefore, these phenomena may cause weaving steps to occur.

In this way, conventional solutions are directed only towards increasing the starting torque of the motor for driving the loom. Therefore, the above problems remain unsolved.

[Purpose of the invention]

Therefore, an object of the present invention is to compensate for the lack of reel beating force at the initial stage of startup while starting the loom without relying on a large starting torque.

[Means for solving the invention]

With the above objective in mind, the inventor focused on a soft start method for general industrial machinery and attempted to apply it to a loom, from the perspective of suppressing sudden changes in acceleration of the rotational drive system of a loom.

However, the conventional soft start method could not be directly applied to looms. The reason for this is that if the conventional soft start method is adopted as is for a loom, the beating force will be insufficient when the loom starts up, creating weaving steps in the woven fabric and degrading the quality of the woven fabric.

However, this lack of beating force can be solved by moving the front of the fabric back from its normal position.

Therefore, the present invention temporarily rotates the clothes winding roll in the opposite direction before starting the loom drive motor,
After the loom is moved back from its normal position by the amount necessary to strengthen the reed beating force, the loom drive motor is started smoothly according to a predetermined pattern, and the loom By strengthening the striking force and suppressing sudden changes in the acceleration of the loom's rotational drive system, it solves technical problems such as the rigidity and durability of the rotational drive system and variations in the beating force.

Furthermore, even when the clothes winding roll is temporarily rotated in the opposite direction, the tension of the warp and fabric can be adjusted to the target level by performing feed-out control and, if necessary, winding control. Maintain tension. Therefore, even during the start-up process of the loom, the occurrence of weaving steps due to tension fluctuations is eliminated.

This soft start method improves the durability of the loom's rotational drive system, eliminates the need for a motor with high starting torque, and reduces the weak beating force at the beginning of startup due to the retreat of the weaving front. Since it is reinforced, weaving steps do not occur, and furthermore, the reeds are less deflected at the beginning of the loom's startup, do not fluctuate, and are always stable, so it is possible to reliably prevent weaving steps when the loom is started.

〔Example〕

Figure 1 shows an overview of the loom.

The warp threads 1 are wound in a sheet form around the delivery beam 2, pass through a tension roll 3 on the delivery side, intersect with the weft threads 5 at the position of the front 4, become a woven fabric 6, and are passed through the auxiliary rolls 7, 8. After being wound around the clothes winding roll 9, it is wound around the winding beam 11 via the tension roll 10 on the winding side.

The delivery beam 2 is driven by a delivery motor 12 . The feed motor 12 is a DC motor, and is controlled by a feed controller 13 and a drive circuit 14. Sending controller 13
is the position of the tension roll 3 and the tension detector 1
5, the tension of the warp yarn 1 is detected, and the rotational speed of the feed-out motor 12 is controlled based on the difference or deviation between the detected tension and the target tension based on the tension feedback control method.

Further, the take-up beam 11 is driven by a take-up motor 16. This winding motor 1
6 is a DC motor, which is controlled by a winding controller 17 and a drive circuit 18. The winding controller 17 detects the tension of the fabric 6 using a tension detector 19 at the position of the tension roll 10, and performs winding based on the tension feedback control method according to the deviation between the detected tension and the target tension. The rotational speed of the take-up motor 16 is controlled to maintain the tension of the woven fabric 6 at a target tension.

The reed 20 is supported by a locking shaft 21 and mechanically interlocks with a crankshaft 22. Here, the crankshaft 22 is driven by a loom drive motor 23. The loom drive motor 23 is an induction motor, and is started in a smooth startup state at the initial stage of startup by an inverter type or phase control type soft start circuit 24.

Further, the clothes winding roll 9 is driven by a clothes winding drive motor 25, which is a DC motor, and is under the control of a control device 26. When the control device 26 receives the start signal S from the operation switch 27, the control device 26 starts the feed controller 13, the winding controller 17, and the soft start circuit 24 in a predetermined order, and also starts the pattern setting device 2.
The rotation of the clothing winding drive motor 25 is controlled by the signal from 8.

Next, FIG. 2 shows the start signal S and the loom drive motor 23 for time t as operations at the start of operation.
The rotation speed N ₂₃ [rpm] of the motor 25 and the rotation speed N ₂₅ [rpm] of the clothes winding drive motor 25 are shown.

When the operator turns on the operation switch 27 at the starting point _t1 , the starting signal S is turned on at the starting point t1.
At _t1 , it immediately changes from "L" level to "H" level. At this time, the control device 26 controls the reversal period T ₁
Inside, the clothing winding drive motor 25 is driven, the clothing winding roll 9 is rotated in the opposite direction, the fabric front 4 is temporarily retreated by an amount commensurate with the reinforcement of the reeding force, and moved in the direction of the reeded reed 20. let The number of rotations (rotational speed) characteristics at this time are determined by the pattern setter 28.
For example, it is set to have an inverted trapezoid shape, and the reversal period T ₁
The total number of revolutions of the clothing winding drive motor 25 is set in consideration of a predetermined amount of retreat of the fabric front 4.

At the subsequent starting time t ₂ , the control device 26 smoothly starts the DC motor 25 in the forward rotation direction, and at the same time or around this time, the control device 26 starts the soft start circuit 2 .
Start 4. The soft start circuit 24 rotates the loom drive motor 23 with a smooth start-up, for example, under a characteristic that has almost the same slope as the start-up speed characteristic of the clothes winding drive motor 25.

In this way, the loom drive motor 23 and the clothes winding drive motor 25 reach the rotational speed during steady operation after the start time t ₂ and the start period T ₂ .
After that, it becomes a stable constant rotation.

In addition, the soft start circuit 24 uses an inverter to increase the output frequency from a low frequency to a commercial frequency, or inserts a triax between the power supply and the loom drive motor 23, and adjusts the drive voltage by controlling the phase of the triax. A soft start is achieved by changing the

During the start-up period T ₂ , the rocking shaft 21 receives the rocking movement of the crankshaft 22 and gives the reed 20 one or more reeling movements. During this time, since the loom drive motor 23 has not reached the steady rotation speed, the reed beating force of the reed 20 is weaker than when the rotation speed is steady.

However, since the weaving front 4 is set at the retreat position to compensate for the weak reeding force, the reeded reed 20
Although the speed is slow, the weft yarn 5 is pushed into the front 4 with a strong pressing force corresponding to the amount of retreat of the front 4, that is, the same pressing force as the steady value.

Moreover, since the loom drive motor 23 gradually increases its rotational speed from a low rotational speed to a steady rotational speed, the amount of deflection of the reed 20 during the startup period _T2 is small.
The amount of variation is also approximately constant each time the device is started, and does not vary each time it is started. Therefore, the startup period
The amount of deflection of the reed 20 at T ₂ can be predicted before starting,
Based on this predicted value, the amount of retreat of the front fabric 4 can be set accurately.

In this way, since the amount of deflection of the reed 20 is small and the amount of variation thereof is almost constant, a nearly constant reed beating force can be ensured each time the loom is started, and the occurrence of weaving steps can be reliably prevented. .

Therefore, even in the transient operating state at the beginning of the loom startup, weaving steps due to weak reeding force can be prevented from occurring, and since the reeding force is stable, it can be prevented from occurring due to fluctuations in reeding force. The occurrence of weaving steps can also be reliably prevented.

Of course, the rotation pattern in the opposite direction of the clothes winding drive motor 25, the rising slope characteristics of the loom drive motor 23 and the clothes winding drive motor 25, etc. have been experimentally determined to be in an appropriate state with the aim of preventing the occurrence of weaving rows. is set to

By the way, when the clothes winding roll 9 temporarily rotates in the opposite direction, the tension of the warp yarns 1 and the woven fabric 6 between the sending beam 2 and the clothes winding roll 9 decreases below the target tension value, and the clothes winding roll The tension of the woven fabric 6 from the winding beam 9 to the take-up beam 11 will rise above a predetermined tension.

Therefore, the feed-out controller 13 and the winding controller 17 detect the tension of the warp yarns 1 and the woven fabric 6 with the tension detectors 15 and 19, and operate the feed-out motor 12 and the winding controller in a direction to correct the detected tension to a target tension value. The take-up motor 16 is driven. These tensions are therefore automatically compensated despite the receding of the front 4. The tension control of the warp yarns 1 and the woven fabric 6 between the sending beam 2 and the clothes winding roll 9 is designed to maintain the position of the front 4 after retraction and to prevent the occurrence of a stop stage. It is preferable to do so. However, since the tension state of the woven fabric 6 from the clothes winding roll 9 to the take-up beam 11 is absorbed by the function of the take-up controller 17 after the loom is started, it is not always necessary when the front loom 4 retreats. Not considered.

[Other Examples]

In the above embodiment, the clothes winding roll 9 is directly driven by the clothes winding drive motor 25, but the rotation direction and speed pattern of the clothes winding roll 9 are as follows.
By connecting the input/output shaft of the operating gear device to the mechanical rotation transmission system of the clothing winding drive motor 25, and controlling the other control shafts of the operating gear device in the forward or reverse direction with a variable speed motor, the input shaft This can also be done by changing the transfer characteristics between the output shaft and the output shaft.

Furthermore, in the above embodiment, the tension at startup is corrected by the sending control and winding control of the tension feedback system. This can also be achieved by simultaneously controlling the winding motor 16 and the winding motor 16 to suppress fluctuations in the tension of the warp yarns 1. Note that when the loom is stopped, the crankshaft 22 suddenly stops within one revolution. The braking force at this time is shared by a plurality of brake mechanisms provided at the respective rotating parts. Therefore, the braking force required for each brake mechanism may be small, and therefore the rigidity required for each brake mechanism is also kept low.

〔Effect of the invention〕

The present invention provides the following unique effects.

Because the loom does not start with sudden acceleration and rotates with smooth speed characteristics, no unreasonable force is applied to the loom's rotational drive system, and mechanical components such as the frame and other mechanical components such as the rotational drive system are The durability of the material is improved.

The motor for driving the loom does not have to have a large starting torque, and can be selected based on the rotational force required during steady operation, so an inexpensive motor for selective driving is sufficient.

At the initial stage of soft start of the loom drive motor, the cloth winding roll reverses and the weaving head independently moves in the backward direction. Since the reeling is performed with approximately the same reeling force as in the steady state, it is possible to prevent the occurrence of stopped weaving rows, etc.

By soft start of the loom drive motor,
The amount of deflection of the reed when the loom is driven is small, and the amount of variation is kept almost constant each time the loom is started. Therefore, even if the amount of deflection in the radial direction of the swing of the reed fluctuates within a narrow range, the amount of variation is small. The occurrence of weaving steps when the loom is started can be reliably prevented without having to be changed each time. Moreover, since the amount of deflection in the longitudinal direction of the reed is small, uniform reed beating force can be ensured across the weaving width direction.
The texture of the woven fabric can also be made almost uniform in the weaving width direction.

Furthermore, even when the front weaves is retreating before starting the loom, the feed control system is in operation and adjusts the tension of the warp and fabric between the feed beam and the clothes winding roll to match the target value during weaving. Therefore, it is possible to prevent the occurrence of weaving steps due to fluctuations in the tension of the warp yarns or the woven fabric.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of the loom, and FIG. 2 is a time chart at startup. 1...Warp thread, 2...Feeding beam, 4...
Before weaving, 6...Woven fabric, 9...Clothing roll, 11
... Winding beam, 12 ... Feeding motor,
13... Delivery controller, 15... Tension detector,
16... Winding motor, 17... Winding controller, 20... Reed, 23... Loom drive motor,
24... Soft start circuit, 25... Clothing winding drive motor, 26... Control device, 28... Pattern setting device.

Claims (1)

[Scope of Claims] 1. Before starting the loom drive motor 23, the cloth winding roll 9 is temporarily rotated in the opposite direction according to a preset pattern to move the loom 4 backward;
A soft start method for a loom, which is characterized in that the loom drive motor 23 is set to a position where the weak beating force at the initial stage of starting the loom is strengthened, and then the loom drive motor 23 is smoothly started to suppress sudden changes in acceleration of the rotational drive system. . 2. When temporarily rotating the clothes winding roll 9 in the opposite direction, at least the feeding controller 13 of the feeding controller 13 and the winding controller 17 is operated, and the clothes winding roll 9 is rotated from the sending beam 2 to the winding roll 9.
2. A soft start method for a loom according to claim 1, wherein the tension of the warp threads 1 and the woven fabric 6 is maintained at a target tension value.