摘要:
A system for inserting a weft thread into a shed of an air jet weaving machine (1) includes a thread store (21) with a measuring apparatus (23.1, 23.2), a plurality of air nozzles (3, 4, 5.1a-c to 5.na-c) for the insertion of the weft thread (2) and a control system (10) which is connected to the measuring apparatus (23.1, 23.2) in order to be able to control the compressed air supply of the air nozzles (3, 4, 5.1a-c to 5.na-c) in dependence on measurement values of the measuring apparatus (23.1, 23.2). Switch on points (xj) are associated with the air nozzles (3, 4, 5.1a-c to 5.na-c), with the control system (10) charging one or more of the air nozzles (3, 4, 5.1a-c to 5.na-c) with compressed air as soon as a predictor value (xF) for the position of the weft thread tip, which is formed with the help of the measurement values, reaches the switch on point (xj) of the relevant air nozzle or air nozzles respectively.
摘要:
A weft inserting control device for fluid jet type loom is provided, including a weft insertion detecting unit for detecting dispersion of the weft reaching angle in a predetermined control cycle; a first comparing unit for comparing a detection value of the weft reaching angle given by the weft insertion detecting unit with a reference value showing an allowable range of the dispersion; and a second comparing unit for comparing the detection value with a threshold value showing a threshold in controlling the dispersion. The weft inserting control device also includes a controlling unit for controlling the weft reaching angle on the basis of the detection value and a result of the comparison carried out by the first comparing unit. The controlling unit controls the weft reaching angle by reducing a predetermined amount of the detection value and by using the threshold value as the detection value, for example, when the second comparing unit reveals the detection value to be over the threshold value.
摘要:
An arrangement for supplying air with a controlled pressure to the main weft insertion nozzles of an air jet loom includes a single servovalve connected between a pressurized air source, an air vent, and a pressure manifold, and individual shut-off valves respectively interposed in branch lines connected from the pressure manifold to the individual nozzles. A pressure sensor measures the actual pressure provided to the manifold. An electronic controller receives a pressure control signal and controls the servovalve responsive to any difference between the pressure control signal and the actual measured pressure signal. The arrangement is simple, economical, and rapidly reacting, to avoid the need of individual throttle valves or pressure regulators for the individual nozzles.
摘要:
A weft inserting control device for fluid jet type loom for detecting dispersion of a weft reaching angle to control the reaching angle of weft yarn is provided, including a weft insertion detecting unit for detecting dispersion of a weft reaching angle in a plurality of control cycles such as a plurality of picking numbers, for example; and a comparing unit for comparing a plurality of detection values of the weft reaching angle given by the weft insertion detecting unit with a plurality of respectively different reference value are provided. The weft inserting control device for fluid jet type loom also includes a controlling unit for controlling the weft reaching angle on the basis of a result of the comparison in every control cycle, the result being obtained by the comparing unit is also provided. The reference value is set so as to have a minus correlation with the length of the control cycle.
摘要:
A valve arrangement of a loom includes valve modules held between flange plates and sharing a common inlet feeding into a common inner valve space. A valve outlet of each valve module leads to an insertion nozzle or nozzle group, and is controlled by a valve disk actuated by a piezoelectric actuator to rapidly dynamically adjust the pressure profile. A quality parameter, characteristic of the thread insertion flight time of each weft thread, is stored in a data bank and has a nominal pressure profile for achieving a nominal thread flight time allocated thereto. The actual thread flight time of each weft thread is measured and compared with the stored nominal thread flight time. A control signal responsive to the time difference is provided to the valve arrangement to control the piezoelectric actuator so as to adjust the pressure and/or the quantity of the pressure medium provided through the valve module to the connected insertion nozzle. Alternatively, the control signal is provided to the main loom rotational drive to adjust the rotational speed of the loom.
摘要:
In a selvedge forming device, the operating condition for operating at least one of the selvedge forming elements contributing to the selvedge formation is set in advance in correspondence to a weaving condition, and the selvedge forming device is operated in accordance with the weaving condition and the operating condition as set in advance, while the weaving process goes on.