摘要:
A motorized rotary drum supported on a motor housing bears a plurality of yarn loops wound thereon, such loops being adapted to be unwound upon request from a downstream machine A yarn-unwinding sensor comprises light-emitting elements and light-receiving elements both of which are integral with the motor housing. Light-guiding elements which are integral with the drum guide the light from the light-emitting elements to a window which is defined on the rotary drum in a position such that it is repeatedly engaged by the yarn during its rotary unwinding motion, and vice versa. A reflecting surface reflects the light coming out of the window back towards the window. Light-deviating elements which are integral with the motor housing deviate the light coming back from the window towards the light-receiving elements. The unwinding of a yarn loop from the drum is determined on the basis of the variation of light resulting from the yarn transiting on the window.
摘要:
Group of optic sensors (S) in a weft feeder, in particular for weaving looms, comprising one or more pairs of emitting sensors (E) and receiving sensors (R) arranged on a portion of the weft feeder (C) which extends laterally to the drum (T) of the weft feeder whereon the coils of the weft thread are wound, so as to form optic radiation going-paths from each of said emitting sensors (E) to a reflecting surface (9) provided on said drum (T) and optic radiation back-paths, from said reflecting surface (9) to corresponding receiving sensors (R), for detecting the presence/absence of a thread which crosses said paths. The optic sensors (E, R) are of the SMT type and are wired on a printed-circuit board (8) with an optic axis parallel to the plane of said board (8). A first group of total-reflection mirrors (V), one for each pair of emitting/receiving sensors (E, R), is inclined so as to deviate the optic radiation from the plane of the board (8) to a plane perpendicular to or inclined with respect to the same. A second group of partial-reflection mirrors (H), one for each pair of emitting/receiving sensors (E, R), is inclined so as to deviate the optic radiation in the same plane as board 8.
摘要:
The invention relates to a method for inserting weft yarn material, comprising an insertion system in a loom. According to the invention, for every insertion the insertion system (A) is supplied with a substantial part of the weft yarn required for the insertion in a loose and substantially tension-free manner so as to be intermittently pulled off. A tubular package of adjacent windings is produced from the weft yarn material on an inner mechanical support (S) by way of an at least substantially continuous winding process and is conveyed forward in withdrawal direction. For an insertion, a number of windings that corresponds at least approximately to the weft yarn section intended to be inserted is detached or set free from the support while maintaining its tubular configuration without yarn tension. The weft yarn material is withdrawn directly inwardly from the frontmost winding and then further along the tube axis (X).
摘要:
The invention relates to a method for inserting weft yarn material, comprising an insertion system in a loom. According to the invention, for every insertion the insertion system (A) is supplied with a substantial part of the weft yarn required for the insertion in a loose and substantially tension-free manner so as to be intermittently pulled off. A tubular package of adjacent windings is produced from the weft yarn material on an inner mechanical support (S) by way of an at least substantially continuous winding process and is conveyed forward in withdrawal direction. For an insertion, a number of windings that corresponds at least approximately to the weft yarn section intended to be inserted is detached or set free from the support while maintaining its tubular configuration without yarn tension. The weft yarn material is withdrawn directly inwardly from the frontmost winding and then further along the tube axis (X).
摘要:
A feeding device for a mechanical weaving machine, including a winding element which can be driven in a rotating manner, a stationary storage, and at least one stop element. The stop element can be axially and radially moved in relation to the storage body, between an unwinding position releasing thread yarn and a stop position wherein the stop element is applied to the foremost winding and which ends the weft insertion. A yarn clamp is arranged downstream from the stop element, which initiates the respective weft insertion, and which can be switched between a passive position and a clamping position. The storage body has a small diameter, and the stop element is moved axially to the stop position solely by the windings due to a transport motion of the windings on the storage body.
摘要:
A method for the operation of a thread supplying apparatus of a weaving machine. The method include transmitting information about a required weft thread to subsequent weft insertions. The information is transmitted after every complete weaving machine cycle to the thread supplying apparatus and at the same time. Thus, the information about the required weft thread of at least one of the two subsequent weft insertions has already previously been transmitted.
摘要:
A device for surveying the insertion of a weft yarn in a shed of a jet loom, comprises an arrival sensor arranged at one end of said shed for detecting the arrival of weft yarn there. The arrival sensor and at least one yarn sensor are connected to a surveillance circuit measuring the period of time lapsed since releasing a stopping device and periodically correcting the measured period of time on the basis of the yarn sensor signal. The surveillance circuit only generates a signal indicating the completion of the weft yarn insertion if the following two conditions are simultaneously fulfilled: The measured period of time exceeds a predetermined period of time between 80% and 99.5% of the period of time required for a complete weft yarn insertion cycle, and the arrival sensor generates a signal representing the arrival of the weft yarn.
摘要:
A method to control the speed of the weft feed spool in weaving looms includes feeding at least two items of detected data related to weft delivery and supply, and loom operation, into a control mechanism, and using the data to calculate as a number of windings, the variation of the weft length reserve from the average minimum desired weft length reserve as determined by an average weft length reserve sensor and adjusting the speed of the feed spool in response to such calculations. A maximum weft length detector may be used as a control for the feed spool as well as a sensor for the time and number of unwindings of weft from the feed spool.
摘要:
A thread-delivery device is disclosed including a storge body formed by bars disposed in the shape of a polygon. The bars form two axially-spaced sections of approximately equal circumferential length. A cylindrical member having sawtooth-shaped threading grooves is rotated between the bars of the first section. The bottom of the threading grooves is located radially inwardly of lines interconnecting the bars. A ring having a conical face is disposed at the thread entrance opening adjacent to one end of the first section and a sensing device is provided to sense the endmost thread wound on the second section.
摘要:
Method of controlling a plurality of relay nozzles (RNx) is a jet weaving machine. These nozzles are consecutively actuated for supporting the insertion of the weft yarn (WY) into the shed of the weaving machine and up to the arrival end (AE) of said shed by means of consecutively opening solenoid valve associated with nozzles. The valves are controlled on the basis of calculated information representing the momentary real position of the weft yarn (WY) during it path in the shed. The invention also relates to an apparatus for carrying out said method.