Abstract: A fuzzy control apparatus for a jet loom detects a flying state of a weft yarn, performs, based on a detected value thus detected, fuzzy inference to determine a modification amount to a rotational frequency of a motor, drives the motor to rotate at a predetermined rotational frequency, and corrects the rotational frequency of the motor based on the correction amount.

Abstract: A weft picking control method capable of realizing control of a weft picking arriving time with a quick response over a wide range. The weft picking control method in an air-jet loom includes supplying air under pressure to weft picking nozzles, and jetting air under pressure from the weft picking nozzles so as to pick a weft into a warp shed together with the jetted air. Also, a supply passage for supplying the pressurized air to the weft picking nozzles includes high and low pressure supply passages. The passages are arranged in parallel with each other, and the air under pressure is jetted from the weft picking nozzles in cooperation with the two supply passages.

Abstract: A control device for weft inserting in a jet loom realizes weft inserting in stable running conditions without depending on the professional perceptions and experiences of operators. The control device for weft inserting is constructed by inferring a corrected value of at least one parameter for weft inserting by fuzzy inference on the basis of at least one operating information relating to the weft inserting in a weaving machine in order to accept an operating condition of the weaving machine at an objective value, and controlling at least one actuator for weft inserting on the basis of the corrected value inferred by the fuzzy inference.

Abstract: A warp feed controller for use in a twin beam weaving machine having a first tension detector for detecting the tension of at least one of the groups of warp yarns fed in sheet-like forms from a pair of warp beams and a first control system for controlling the rotation of one of the warp beams on the basis of the tension deviation from a target tension under detection of the tension by the tension detector. The controller also includes a pair of second tension detectors for detecting the tensions of the warp yarns fed from the warp beams in boundary portions of the sheet-like forms, and a second control system for controlling the rotation of the other of the warp beams on the basis of the tension difference output from the second tension detectors, respectively.

Abstract: A method of optimizing control of looms for the improvement of the economic efficiency of a weaving mill controls set points for the looms so that the economic efficiency of the weaving mill will not be reduced below a standard economic efficiency determined through preparatory test operation of the controlled looms. The controlled looms are operated for a predetermined preparatory test period for preparatory test operation to collect the data of parameters dominating the economic efficiency of the weaving mill and to create reference data. Data of the parameters are collected in a monitoring period during the practical operation of the looms and the data is normalized by the time of the monitoring period to create operation data. The set points for each loom are corrected on the basis of the result of comparison between the reference data and the operation data to determine new set points.

Abstract: A method and an apparatus for controlling weft inserting without depending on any operation skill, such control being on the basis of at least two kinds of information having mutually different frequencies for correcting weft inserting. A plurality of control rules prepared according to control algorithms, a plurality of data tables for weft inserting prepared according to the control algorithms or approximate expressions are used for calculating the control conditions of an actuator for weft inserting, and the weft inserting actuator is controlled on the basis of the calculated control conditions.

Abstract: A device for noise attenuation attenuates the noises generated from weaving machines and comprises first conversion means for receiving a sound and outputting an electrical acoustic signal corresponding to the sound, first signal processing means for receiving the acousto-electric signal and outputting a first electrical signal having the frequency and amplitude corresponding to a sound to be attenuated on the basis of the received acoustic-electric signal, second signal processing means for receiving the first electrical signal and outputting a second electrical signal having the same frequency and inverted phase relative to the first electrical signal, and second conversion means for receiving the second electrical signal and generating a sound corresponding to the received second electrical signal.

Abstract: A control method for the rotational frequency of a weaving machine comprises the steps of performing a plurality of times of trial runnings of the weaving machine at different trial rotational frequencies to obtain the operating time for each rotational frequency, obtaining at least one indefinite coefficient in the formula representing the relation between a rotational frequency factor and an operating time factor by utilizing each obtained operating time and each trial rotational frequency, obtaining the optimum rotational frequency, at which the quantity of production reaches the maximum, on the basis of the obtained at least one indefinite coefficient and fuzzy inference, and controlling the rotational frequency of the weaving machine into the obtained optimum rotational frequency.

Abstract: A control method for a weaving machine comprises the steps of obtaining the rotational frequency to be varied by the use of the fuzzy interference on the basis of the evaluation index representing the running condition level of the weaving machine, and then varying the actual rotational frequency of the weaving machine on the basis of the obtained rotational frequency. As the evaluation index, use is made of the control allowance level of the weaving machine, the quality allowance level of woven fabric, the working allowance level of the operator, the stop level of the weaving machine, the rate of a change value of the stop level to a variation value of the rotational frequency or the operating rate of the weaving machine.

Abstract: A method of controlling an operating speed of the loom for increasing the production rate by varying the present operating speed so as to be increased includes a step of estimating a stop rate at the final point of time during a predetermined period at a certain time during the predetermined period, and comparing the estimated stop rate with a predetermined limit stop rate, and setting the present operating speed to increase it when the estimated stop rate is less than the limit stop rate and to decrease it when the estimated stop rate exceeds the limit stop rate.

Abstract: An optimum loom control method controls a loom so that the overall profit of a weaving mill is maximized. A profit evaluation function defining a profit evaluation valve includes variables including those affecting the profit of the weaving mill, such as information on the quality of fabric woven, the number of effective picks representing the quantity of fabric produced, and the energy consumption of the loom. A controlled factor or factors corresponding to a controllable variable or variables from among those of the profit evaluation function, namely, the operating speed of the loom, the pressure of the picking fluid or both the operating speed of the loom and the pressure of the picking fluid, are controlled so that the profit evaluation value is increased to a maximum.

Abstract: A centralized loom control method employing a host computer for controlling the operation of a plurality of looms. Data base including data accumulated by recording past actual weaving conditions in stored in a memory device connected to the host computer. The host computer determines standard set value for which the looms are to be set by processing the specifications of a fabric to be woven entered therein and data fetched from the memory device through predetermined calculation or interpolation. The host computer compares a standard operating speed among the standard set values with a target operating speed at which the loom is to be operated, and changes the standard set values according to the result of comparison to provide new standard set values suitable for operation at the target operating speed.

Abstract: The present invention relates to a control system for an engagement pin employed in a drum-type weft storage unit which is mainly employed in a jet-loom for storing the weft and for measuring the same in length. A novel control system for an engagment pin employed in a drum-type weft storage unit is provided. An engagement-time is compensated on the basis of a difference in time between a target-time later than the engagement-time of the engagement pin by a normal time-lag, to make it possible that the engagement-time is always set to be optimum in spite of the existanece of variation in shuttling speed of the weft, so that it is possible to keep the variation in length of the delivered weft minimum while the weft feeler is employed in place of the disengagement sensor.

Abstract: A warp tension control method by which the let-off motion of a loom is controlled to regulate the tension of the warp yarns. A force of the same dimension as the controlled variable, namely, the tension of the warp yarns, is applied to a mechanism supporting the tension roller of the let-off motion for displacement under the control of an electric control system to control the warp tension at a high accuracy.

Abstract: 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.

Abstract: A pick spacing controlling device of the digital system for controlling the pick spacing of a fabric being woven on a loom having a main motor for driving the principal weaving mechanism of the loom, and a take-up motor for driving the take-up roller of the loom by controlling the output rotation amount of the take-up motor so that the output rotation amount of the take-up motor varies in direct proportion to that of the main motor or that of the principal part of the loom. The output rotation amount of the take-up motor and that of the main motor or the rotation amount of the principal part of the loom are detected by encoders. An arithmetic unit processes pulse-number modulated input signals corresponding to the output pulse signals of the encoders to obtain the difference between the pulse-number modulated input signals in the number of pulses, and then a driving actuator drives the take-up motor so that the difference is reduced to zero.

Abstract: Practice of an auto-repair operation on a loom is automatically prohibited when the frequency of auto-repair operation exceeds a preselected rate in order to avoid production of off-grade cloths otherwise caused by continuously repeated formation of weaving defects.

Abstract: Motor-driven let-off and take-up motions in a loom are controlled by controlling the rotation of a motor for driving warp yarns with a tension control system operating in response to a signal indicative of a target tension and a feedback input signal indicative of an actual tension of the object during a normal operation of the loom, and controlling the rotation of the motor with a feedforward control system during a transient operation of the loom, the feedforward control system storing operation patterns of directions, and speeds of rotation and angular displacement of the motor for respective operation modes and weaving conditions of the loom. At the time of the transient operation, and operating condition of the loom is detected, an appropriate operation pattern is read from the feedforward control system based on the detected operation mode, and the read operation pattern is applied as a control signal to a drive control system for the motor.

Abstract: A weft inserting apparatus in a jet loom comprises a nozzle for inserting a stored weft yarn through a shed on a jet of fluid, weft insertion control means such as a control valve for controlling the starting and ending of the insertion of the weft yarn through the shed, and a control unit for determining a delay time based on a rotating condition of the jet loom at least under a transient operating condition of the jet loom, and for controlling the weft insertion control means to allow the weft yarn to be inserted for a prescribed period upon elapse of the delay time after an angle for starting apparent weft insertion.

Abstract: 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.