摘要:
A device for inserting of weft threads in an air jet weaving machine comprising at least one set of main nozzles (13, 14) which are mounted in series, to which each time a regulating valve (21, 22) is assigned, is provided with a control and regulating unit (17) which defines the settings of the regulating valves (21, 22) of a set of main nozzles (13, 14) with respect to one another, in order to form an overall value for the intensity of the impulse transmission of the set of main nozzles.
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:
A picking period setting device for a loom to decide an appropriate picking period for satisfactory picking operations. A shedding curve calculating circuit is used which calculates shedding curves representing the shedding motion of heddle frames. A shedding stroke calculating circuit calculates a set of desired shedding stroke curves. An appropriate picking period deciding circuit decides a precise picking period defined by the crank angles of the loom on the basis of the result of comparison of the shedding curves and the desired shedding stroke curves. Thus, the weaving operation of the loom is continued without interruptions caused by faulty picking.
摘要:
Multiple-color air jet looms successively insert different kinds of weft threads into warp sheds to weave a fabric of desired construction. The different weft threads are subjected to different resistances to their being drawn through a main nozzle and are carried on air jets under different conditions, so that the weft threads will be inserted unstably at different speeds. With the arrangement of the invention, selected weft threads for insertion are carried, one at a time, through the warp shed under respective different weft carrying forces suited for the weft threads. The different weft carrying forces may be produced by varying pressures at which air is ejected, intervals of time during which air is ejected under pressure, or the manner in which subnozzles are positioned along the warp shed. There is provided a control means for changing the air pressures and ejection time intervals in synchronism with operation of the air jet loom.
摘要:
A device for periodically supplying measured quantities of a pressure fluid to a nozzle adapted to blow a weft thread into the shed of a pneumatic loom, comprising a metering chamber fed by a pressure fluid source and connected to the nozzle through a periodically opening valve means, control means being provided to influence the behaviour of the weft thread and more particularly to stabilize the position of the weft thread in the fluid jet irrespective of the nature of that thread.
摘要:
Air-jet weaving machine with an apparatus for the supply of compressed air with several pneumatically adjustable pressure regulators (1.1, 1.2, 1.3), wherein the pneumatically adjustable pressure regulators (1.1, 1.2, 1.3) respectively comprise a pneumatic control inlet (3.1, 3.2, 3.3). Furthermore an electrically controllable pressure adjusting means (4) and a control pressure line (5) is present, in which various different air pressure values are producible by the electrically controllable pressure adjusting means (4). To each pneumatic control inlet (3.1, 3.2, 3.3), an electrically switchable valve (6.1, 6.2, 6.3) is allocated, by which the pneumatic control inlet (3.1, 3.2, 3.3) is connectable with the control pressure line (5).
摘要:
A method for transporting the weft thread through the shed of an air-jet weaving machine having a nozzle fed with a flowing transportation medium, wherein the portion, changeable along the weft thread, of the natural thread charges arranged irregularly on the weft thread is contactlessly registered by means of an electrode array, wherein the changing total charge is determined on the electrode array, wherein the periodic change in the total charge is evaluated for determining the axial velocity of the weft thread, and wherein the nozzle of the weaving machine is controlled as a function of the axial velocity of the weft.
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:
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 apparatus for controlling weft inserting enables the calculation of accurate pressures suitable to an actual weft and weft inserting device. One or more definite weaving conditions determined by one or more manufacturer's textile and weaving machine specifications and one or more indefinite weaving conditions determined by human senses are inputted to a fuzzy inference circuit in which the pressure value of fluid supplied to a weft inserting nozzle is calculated by fuzzy inference on the basis of the definite and indefinite weaving conditions thus inputted. The weft inserting pressure of the fluid delivered to the weft inserting device is adjusted on the basis of the inferred value.