Textiles: weaving – Fabric manipulation – Take-ups
Reexamination Certificate
2001-11-06
2002-08-13
Falik, Andy (Department: 3765)
Textiles: weaving
Fabric manipulation
Take-ups
C242S547000, C242S535300
Reexamination Certificate
active
06431220
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a take-up motion control system for a loom, capable of driving a cloth roller, i.e., winding roller, by a controllable motor to take up cloth woven on the loom in a roll of cloth, and of controlling the tension of the cloth by a program according to the variation of the diameter of the roll of cloth.
2. Description of the Related Art
A known technique disclosed in JP-A No. 60-17151 interlocks a cloth roller, i.e., a winding roller, with a drive shaft by a friction clutch, which serves as a mechanical brake, including a friction plate and a pressure plate. The pressure plate is pressed against the friction plate by an appropriate pressure so that the friction plate and the pressure plate may properly slip relative to each other and a proper braking force may be generated. The driving force of the main shaft of the loom may be transmitted to the cloth roller to rotate the cloth roller by a predetermined torque.
This known technique measures change in the diameter of the roll of cloth mechanically, and adjusts the pressure pressing the pressure plate against the friction plate mechanically according to the change of the diameter of the roll of cloth to control the cloth tension by changing the torque of the drive shaft for driving the cloth roller. The relation between the cloth tension F, the torque T of the drive shaft and the radius R of the roll of cloth is expressed by F=T/R.
Even if the torque of the drive shaft for driving the cloth roller is controlled mechanically according to the change of the diameter of the roll of cloth by this known technique, the cloth tension cannot be properly adjusted according to the variation of the diameter of the roll of cloth and, consequently, the cloth is liable to be creased. If creases are defects in the cloth, the cloth cannot be woven in a satisfactory quality unless the braking force is adjusted while the loom is in operation.
The braking force can be adjusted by controlling the mechanical brake according to the diameter of the roll of cloth by an actuator, such as apneumatic cylinder actuator. However, the ability of the mechanical brake deteriorates with time and the braking performance of the mechanical brake changes as the components thereof are abraded. Therefore, the mechanical brake needs periodic maintenance. The braking force can be generated by a powder clutch, and can be controlled by electrically controlling the powder clutch. However, the performance of powder included in the powder clutch changes with time and the powder clutch needs periodic maintenance.
A known technique disclosed in JP-U No. 52-21807 suspends a cylindrical member, i.e., a pressure roller, having a length greater than the width of a roll of cloth formed by rolling cloth so as to press the roll of cloth to roll the cloth around a cloth roller in a uniform, satisfactory shape. The pressure roller is pressed against the roll of cloth by its own weight or by elastic members, such as springs. Thus, the cloth is rubbed by the pressure roller before the same is taken up on the cloth roller. The pressure roller applies pressure uniformly to the entire roll of cloth as the cloth roller rotates to prevent the formation of creases in the cloth rolled in the roll of cloth.
Since the pressure roller applies a fixed pressure to the roll of cloth regardless of different weaving conditions for different types of cloth, the pressure roller is unable to prevent the formation of creases in the cloth under some weaving conditions. Since the pressure applied to the roll of cloth remains constant regardless of the variation of the diameter of the roll of cloth, an appropriate pressure, which must be varied according to the diameter of the roll of cloth, cannot be applied to the roll of cloth having a variable diameter and hence creases are liable to be formed in the rolled cloth.
A plurality of pressure rollers respectively having different weights may be selectively used according to weaving conditions to prevent the formation of creases in the rolled cloth. However, management of parts necessary for the selective use of the plurality of pressure rollers is troublesome and is practically infeasible.
SUMMARY OF THE INVENTION
Accordingly, it is a first object of the present invention to achieve the appropriate control of winding tension exerted on cloth being taken up in a roll of cloth on a cloth roller according to the change of the diameter of the roll of cloth without requiring any periodic maintenance work.
The cloth roller is driven for rotation by a torque-controllable motor to control tension exerted on the cloth by a program control mode according to the change of the diameter of the roll of cloth formed by rolling the cloth on the cloth roller.
According to a first aspect of the present invention to achieve the first object of the present invention, a take-up motion control system for controlling a take-up motion included in a loom comprises: a torque-controllable motor for driving a cloth roller, a diameter measuring device capable of providing an electric signal representing the diameter of a roll of cloth formed by winding cloth around the cloth roller, and a motor controller capable of controlling the torque-controllable motor according to a control program on the basis of the electric signal provided by the diameter measuring device and representing the diameter of the roll of the cloth.
The take-up motion control system according to the first aspect of the present invention executes the tension control program for controlling the torque-controllable motor on the basis of the electric signal representing the diameter of the roll of cloth to adjust the tension exerted on the cloth properly according to the diameter of the roll of cloth. Thus, the formation of creases in the cloth rolled in the roll of cloth can be prevented and any maintenance work is not necessary because the take-up motion control system does not include any device subject to deterioration with time, such as a mechanical brake.
In the take-up motion control system according to the first aspect of the present invention, proper tensions are determined for different diameters of the roll including a minimum diameter at the start of winding the cloth and a maximum diameter at the end of winding the cloth according to weaving conditions, and a tension control program for controlling tension exerted on the cloth according to the variation of the diameter of the roll from the minimum to the maximum diameter is created. Since the tension control program for controlling the tension exerted on the cloth according to the variation of the diameter of the roll from the minimum to the maximum diameter is created, appropriate tensions can be exerted on the cloth according to the diameter of the roll of cloth. Hence, the formation of creases in the cloth rolled in the roll of cloth can be prevented even if the cloth is of a delicate type.
In the take-up motion control system according to the first aspect of the present invention, a graph indicating the relation between the diameter of the roll of cloth and the tension may be created on the basis of the tension control program, and the set tensions may be changed by shifting a point or a line on the graph. Since the set tensions are thus changeable by shifting the point or the line on the graph indicating the relation between the diameter of the roll of cloth and the tension, desired values can be readily set and changed, tension setting work can be achieved in a short time, and dispersion in set tensions between different looms can be prevented.
In the take-up motion control system according to the first aspect of the present invention, a present tension and a present roll of cloth diameter may be measured and displayed. When a present tension and a present roll of cloth diameter are measured and displayed, a tension and a diameter when the cloth rolled in the roll of cloth is creased can be recognized, and the set values can be properly changed to prevent the for
Kakutani Kazuto
Nakada Akihiko
Oota Yasunori
Tamura Zenji
Falik Andy
Tsudakoma Kogyo Kabushiki Kaisha
Wenderoth , Lind & Ponack, L.L.P.
LandOfFree
Take-up motion tension and/or pressure control system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Take-up motion tension and/or pressure control system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Take-up motion tension and/or pressure control system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2926180