Textiles: weaving – Weft manipulation – Weaving with stationary weft supply
Patent
1987-08-28
1989-07-18
Jaudon, Henry S.
Textiles: weaving
Weft manipulation
Weaving with stationary weft supply
25112921, D03D 4730
Patent
active
048484164
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a nozzle device for inserting of a weft yarn through the shed of a weaving machine by means of a jet of pressurized medium.
BACKGROUND OF THE INVENTION
In jet weaving machines the weft yarn is inserted through the shed by means of a pulse-like jet of fluid normally air. The necessary jet of pressurized medium is generated by a nozzle device, which in conventional jet weaving machines comprises a nozzle mounted on a sley in the weaving machine which is supplied by a pressure medium from a valve device positioned stationarily in the weaving machine, which is controlled by an electric control unit operating the valve device in synchronism with the operation of the weaving machine. In addition to a so-called main nozzle, which is arranged at the insertion side of the weft yarn in the weaving machine outside the shed, so-called relay-nozzles are arranged on the sley in the shed at equal distances from one another, which relay nozzles are also connected to valve devices which are stationarily arranged in the weaving machine and controlled by the electric control unit thereof. The electric control unit of the weaving machine successively operates the main nozzle and the respective relay nozzles during each pick or weft yarn shot for bringing the weft yarn to the arrival end in the shed. The volume of pressurized medium contained in the ducts between the respective valves and the respective nozzles of these conventional nozzle devices having separate valves and nozzles results in considerable response times which in turn negatively affect the control behaviour of the overall system. Another type of nozzle device having an integrated valve is known from U.S. Pat. No. 4,466,468. This prior art nozzle device comprises a supply for pressurized medium, an outlet nozzle in the form of a passageway through which the weft yarn is guided, a conduit connecting the supply and the outlet nozzle and a valve unit arranged between the supply and the outlet nozzle. The conduit includes an outer storage chamber which, in the open position of the valve unit, is in connection with a cone-shaped duct terminating at the nozzle passageway. The cone-shaped duct and the outer chamber are separated by a rounded edge which is in contact with a flexible diaphragm extending in the radial direction of the device which diaphragm and edge together form the valve unit. The position of the diaphragm is controlled by the pressure of a control air which is fed to the prior art nozzle device by separate solenoids or rotary spool valves. When reducing the pressure of the control air the diaphragm is bent away from the rounded edge so that the pressurized medium flows from the storage chamber to the outlet nozzle. The dynamic control behaviour of this prior art nozzle device is subject to inherent limitations caused by the two-stage valve design necessitating a servo-valve for controlling the operation of the main valve in the form of the diaphragm. In other words, the overall response time of this prior art nozzle device is necessarily longer than the sum of the response times of the servo-valve unit and of the nozzle device itself. Moreover, this prior art nozzle device has a complicated mechanical design caused by the necessity of a diaphragm and a conduit in the form of an outer storage chamber and a cone-shaped duct terminating at the outlet nozzle.
In view of the above prior art nozzle devices, the present invention is based on the object of achieving a nozzle device having a favourable dynamic behaviour although having a relatively simple design.
This object is achieved by a nozzle device in accordance with the claims hereof.
In accordance with the present invention, the valve unit comprises a displaceable soft-magnetic valve body and a coil for generating a magnetic field extending through the soft-magnetic valve body when feeding an actuation current to the coil. The displaceable, soft-magnetic valve body is arranged within the conduit such that the flowing of pressurized medium thro
REFERENCES:
patent: 3519030 (1970-07-01), Vermeulen
patent: 3628767 (1971-12-01), Lombard et al.
patent: 4212330 (1980-06-01), Von Donk
patent: 4441687 (1984-04-01), Pauliukonis
patent: 4466468 (1984-08-01), Brouwer
patent: 4471818 (1984-09-01), Brouwer et al.
patent: 4625770 (1986-12-01), Ishikawa
Aktiebolaget IRO
Jaudon Henry S.
LandOfFree
Weft yarn insertion nozzle device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Weft yarn insertion nozzle device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Weft yarn insertion nozzle device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-164077