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: A picking control method includes the steps of detecting a change in the supply yarn package during the weaving operation, preferentially setting a specific checking pin retracting time in which the checking pin is to be retracted for picking cycles for a predetermined time period after the detection of the change of the supply yarn package, and controlling the advancing and retracting operation of the checking pin on the basis of a new checking pin retracting time. A picking controller for carrying out this method has a supply yarn package change detector for detecting the change of the supply yarn package and for issuing a supply yarn package change detection signal, an initial data setting device for providing a checking pin retracting time in which the checking pin is to be retracted to release the weft yarn supplied from the new supply yarn package and wound on the measuring and storing drum, a data updating device generating a checking pin retracting time, a memory device, and a control unit.

Abstract: In a fluid jet loom, almost all the faulty picks are attributable to defects in the quality of the weft yarn. The present invention detects matters for evaluating the physical properties of the weft yarn or matters for evaluating the result of the picking operation during the picking operation, discriminates the quality of the yarn package on the basis of data obtained through the detection, and automatically changes the yarn package for a new yarn package when it is decided that the yarn package feeding the weft yarn at present is defective.

Abstract: A wireless let-off and take-up control system for controlling the let-off motion and take-up mechanism of a loom or looms by wireless. The control system comprises a portable transmitter or transmitters, and a receiver or receivers each associated with the controller of a loom for controlling the let-off motion and take-up mechanism of the loom. Instructions for controlling the let-off motion and the take-up mechanism are given by wireless by operating the transmitter through the receiver to the controller of the loom at an optional position around the loom, so that a single operator is able to observe the movement of warps and, if necessary, to vibrate the warps in order to enable the warps to move smoothly past the droppers, the mails of heddles and reed of the loom in preparing a new warp beam for weaving operation on the loom.

Abstract: A weft storage device has a drum around which a weft yarn is wound by a rotatable yarn guide, weft yarn withdrawal from the drum being controlled by a movable engaging pin. When the weft yarn breaks, any yarn remaining on the drum is cut off and the scraps are withdrawn by a suction arrangement. The yarn guide is moved to an angular position near the suction arrangement so an end of the yarn is held by the suction arrangement, and then to another angular position. A guide part then engages the yarn between the suction arrangement and yarn guide and moves it to the inlet of an injection nozzle, the air flow in the nozzle then threading the yarn into the nozzle. The engaging pin is then actuated to hold the yarn on the storage drum, and the yarn guide then winds a predetermined number of turns of the yarn onto the drum.

Abstract: In a picking apparatus comprising: a weft yarn measuring and storing device including pick length adjusting mechanism capable of varying pick length, for winding a weft yarn on a weft yarn measuring drum to measure and store the weft yarn on the weft measuring drum; a picking nozzle for inserting the weft yarn released from the weft yarn measuring drum into a shed of warp by means of a fluid jet; and a weft yarn detector disposed at a fixed position on the weft yarn arrival side, outside and near the warp; a pick length setting method comprising: a data input process in which data at least including a target adjustment length is given to calculating means; a calculating process in which data corresponding to the target adjustment, for adjusting the setting of the pick length adjusting mechanism is obtained through calculation; a pick length adjusting process in which an initial pick length is diminished or increased gradually during tentative picking operation to a pick length which causes the weft yarn detec

Abstract: A weft yarn feed device (1) comprises a measuring and storing drum (7) for storing a predetermined length of a weft yarn (4) thereon for picking operation, a rotary yarn guide (6) for winding the weft yarn (4) on the measuring and storing drum (7), a feed motor (8) for rotating the rotary yarn guide (6), a drive control unit (3) for controlling the operation of the feed motor (8), and a command control unit (2) which gives commands to the drive control unit (3). The length of the weft yarn (4) wound on the measuring and storing drum (7) is detected accurately on the basis of the relation between the number of rotation of the rotary yarn guide (6) and that of the crankshaft of the loom, and a detection signal indicating the length of the weft yarn (4) wound on the measuring and storing drum (7) is fed back to the command control unit (2) to control the feed motor ( 8) properly for winding a predetermined length of the weft yarn (4) on the measuring and storing drum.

Abstract: A weft yarn is wound on a storage drum, and is withdrawn from the storage drum and inserted into a shed of a loom by a picking arrangement. A retaining pin is movable between first and second positions in which it respectively permits and obstructs removal of the yarn from the drum. A sensor is provided at a location spaced from the arrival end of the shed. A control arrangement responsive to the sensor effects movement of the retaining pin, and adjusts the point in time at which it moves the pin from its second to its first position in response to signals generated by the sensor during yarn insertion.

Abstract: A weft yarn storing device having a rotary yarn guide for winding a weft yarn on a measuring and storing drum, a motor for driving said rotary yarn guide for rotation, which comprises a controller. The controller comprises a frequency pattern generator which generates, upon the reception of a start signal, a control frequency signal of a control frequency pattern having a creep of a low frequency in a deceleration period in which the motor is decelerated; a voltage pattern generator which generates a control voltage signal corresponding to the frequency of the control frequency signal; a pulse width modulating unit which generates a pulse width modulated signal on the basis of the control frequency signal and the control voltage signal; and a driver which applies a DC voltage intermittently to the motor according to the output signal of the PWM unit.

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: An automatic picking conditions regulating device regulates the picking conditions of one of the same of a picking device having a picking nozzle which picks a weft yarn by jetting a pressurized picking fluid, in order to pick a weft yarn so that the same arrives at a predetermined position at a target weft yarn arrival crankshaft angle. When the weaving conditions of the loom are changed, a picking condition, such as the pressure of the picking fluid or the jet starting crankshaft angle, is varied sequentially, the corresponding actual weft yarn arrival crankshaft angles are measured, and then the values of the controlled picking condition and the measured actual weft yarn arrival crankshaft angles are used to determine an optimum value of the picking condition for making the actual weft yarn arrival crankshaft angle coincide with the target weft yarn arrival crankshaft angle.

Abstract: A mispick removing device capable of extracting the broken pieces of a mispick through the opposite selvages of the fabric, respectively, in case of the breakage of a picked weft yarn within the shed, and capable of extracting a mispick through the selvage of the fabric on the picking side of the loom in case of faulty picking operation other than the breakage of the picked weft yarn. The mispick removing device comprises a picking-side mispick removing mechanism disposed on the picking side of the loom, and a receiving-side mispick removing mechanism disposed opposite to the picking-side mispick removing mechanism with respect to the fabric. The mispick removing device is controlled automatically for mispick removing operation.

Abstract: A faulty picking diagnosing system for a fluid jet loom equipped with a fluid jet picking device. The faulty picking diagnosing system is capable of diagnosing a faulty picking cycle while the loom is in operation, to specify the causative parts of the faulty picking cycle among the functional parts of the loom, through the detection of acutal weft yarn unwinding times when coils of the weft yarn stored on the measuring and storing drum of the loom are unwound, respectively, and actual weft yarn arrival times when the free end of the picked weft yarn arrives at predetermined detecting positions, respectively, and comparing the detected data with the corresponding target values.

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: A weft insertion control method for controlling the operation of a weft inserting device which measures and reserves a weft by winding the weft on a stationary measuring and reserving drum by means of a rotary yarn guide, releases the weft from and detains the same on the measuring and reserving drum by reciprocating a detaining pin to the measuring and reserving drum, and picks the weft wound and reserved on the measuring and reserving drum by a picking nozzle, including a detaining pin driving process in which a present weft releasing angle and a reference weft detaining angle are compared with the phase angle the loom, the detaining pin is retracted at the weft releasing angle to separate the detaining pin from the circumference of the measuring and reserving drum and the detaining pin is advanced at the reference weft detaining angle to bring the detaining pin into abutment with the circumference of the measuring and reserving drum; a detecting process in which the number of winds of the weft unwound from

Abstract: When a weft yarn is broken between a yarn supply and a main nozzle in a weft inserter, the weft yarn is automatically removed and replaced by threading a new weft yarn to a prescribed position in a storage drum and then carrying out auxiliary winding of the new weft yarn around the storage drum. The new weft yarn wound around the storage drum is then threaded to the main nozzle.

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 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.

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: The ends of warp yarns in a sheet form are treated at the end of a sizing process in preparation for a subsequent rewinding process. In the sizing process, the warp yarns are threaded through a reed with at least two warp yarns in each reed dent in vertically spaced relation. The at least two warp yarns are threaded through one dent in a reed in the rewinding process. Heretofore, it has been tedious and time-consuming to thread the warp yarns through the reeds since the warp yarns in one reed dent cannot be distinguished from those in other reed dents in the sizing process. In the rewinding process, a spacer such as a rod is inserted between vertically divided sheets of the warp yarns to prevent snarling. Since the warp yarns cannot be distinguished from reed dent to reed dent, it has been difficult to insert the spacer.