Tsudakoma Corp.

Toshiyuki Sakano

Tsutomu Sainen

Yoshitaka Fujita

Koyu Maenaka

Takeshi Asai

Toshio Nakagawa

Toshiki Imai

The optimum control conditions for a plurality of looms are simply estimated with the use of a trial loom. Hereby, the plurality of looms are operated under a centralized control method. The looms, even if they vary in their respective characteristics, can be effectively operated by correcting standard control data for controlling the looms in response to variations of the loom characteristics. The present centralized control method can save much labor and time to improve productivity of the looms, by properly eliminating elaborate trial weaving processes.

Centralized control method for loom and device thereof

A takeup motion control device for a loom includes an input setting unit for producing functions of a repetitive period and a takeup speed, a function generator for storing the functions in relation to r.p.m. of the loom, an arithmetic control unit for successively reading out the selected functions from the function generator in synchronism with rotation of the loom to generate a digital takeup command signal, a driver circuit for generating a drive signal in response to the takeup command signal and applying the drive signal to a servomotor for driving a winding roll to wind a woven fabric, and a digital feedback circuit for feeding an amount of rotation of the servomotor back to the arithmetic control unit.

Takeup motion control device for looms

An apparatus for controlling a let-off motion in a loom having a let-off motion motor includes a tension detector for detecting a warp tension to produce a tension correction signal, a control unit responsive to the tension correction signal for producing a speed signal, a driving amplifier for controlling the let-off motion motor in response to the speed signal, a warp coil diameter detector for issuing a warp coil diameter correction signal inversely proportional to the diameter of a warp coil on a beam to the driving amplifier, and a normal-reverse rotation control unit responsive to the warp coil diameter correction signal for selectively applying prescribed normal- and reverse-rotation signals dependent on a rotation command to the driving amplifier. With this arrangement, the motor is rotated at a desired constant speed for feeding out or rewinding the warp yarn for a desired length irrespectively of the warp coil diameter. In an inching mode of operation, the motor is rotated in a normal or reverse direction for an interval equivalent to one pick each time a main shaft of the loom turns past a certain rotational angle, so that the warp yarn is kept under a desired tension.

Apparatus for controlling motor-driven let-off motion for looms

A method of controlling a motor-driven let-off motion in a loom including a system for controlling a let-off motion motor includes the steps of sampling a variation of warp tension during each revolution of a main shaft of the loom, effecting at least proportional and integral control modes on the average of sampled values, adding a proportional and integral output to a basic speed signal at a prescribed ratio, and applying a sum signal to the system for controlling the let-off motion motor. An apparatus for controlling a motor-driven let-off motion in a loom including a system for controlling a let-off motion motor includes an average computing unit for computing the average of warp tension variations detected at a plurality of sampling times while a main shaft of the loom revolves, a control unit for effecting at least a proportional and integral computation on the average to produce a proportional and integral output, a basic speed computing unit responsive to information indicative of the number of RPM of the main shaft of the loom, the diameter of warp coils on beams, and the number of beatings for computing a basic speed, and a speed command computing unit responsive to the proportional and integral output and the basic speed for adding the proportional and integral output to the basic speed at a prescribed ratio to generate a speed command signal and for applying the speed command signal to the system for controlling the let-off motion motor. With this arrangement, there is no time-delay element in the control system and hence any tension variations can be detected quickly. When the loom is stopped in operation, the integral of a warp tension prior to the stoppage of the loom is stored. When the loom is restarted, the stored integral is issued to suppress any unwanted tension variations of the warp yarns. Since a tension compensation gain is not relatively varied when the diameter of a warp coil is changed, the control system can provide ideal control characteristics.

Growing community of inventors

Kanazawa, Japan

Toshiyuki Sakano