Abstract:
A machine for printing a recurrent pattern on sections of predetermined length of a textile web, comprising a number of parallel rotary-screen printing units spaced apart in the direction of web motion, includes a first sensor for detecting the leading edge of an oncoming web section to be imprinted and a second sensor for ascertaining the passage of a mark indicating the start of a printing pattern on the first unit. The odd-numbered units print the first half of the pattern, in different colors, whereas the even-numbered units print the second half in corresponding colors; between printing operations, the screen of each unit is lifted off the web and can be angularly readjusted to compensate for relative disalignment between the web sections and the printing patterns. Such disalignment is determined by the two sensors whose output signals are translated into command signals sequentially delivered to control inputs of the several odd-numbered units at equal intervals for making the necessary adjustments just before the arrival of the leading edge of a web section at these units; the control inputs of the even-numbered units receive these commands at instants delayed with reference to the midpoints of these intervals so that their adjustments take place after that leading edge has passed them. Where the sections to be imprinted are tufted fabric piles, the first sensor comprises two juxtaposed feelers, one loaded by a hard spring and the other loaded by a soft spring; an oncoming pile edge elevates the latter but not the former to cause completion of a signal circuit discriminating against seams in the web which would cause both feelers to be elevated concurrently.
Abstract:
A dyestuff applicator, located inside a cylindrical printing screen, comprises a horizontal ink tube which supports an axially extending ink-distributing member with freedom of relative mobility in a vertical axial plane of the tube. The distributing member, resting on the inner screen surface, forms a discharge slot communicating with the interior of the tube through a multiplicity of conduits closely spaced along the tube axis, the conduits being disconnectable from the slot with the aid of an axially slidable or rotatable shutter common to all the conduits and lodged in the distributing member. This distributing member is weighted down by the pressure of the ink in an overlying space, or by springs or fluid cushions inserted between that member and the tube.
Abstract:
Apparatus and methods for surface layer atmospheric turbulence differential image motion measurement provide the ability to measure and characterize the atmospheric turbulence in a surface boundary layer with applications to a wide variety of technical areas including, but not limited to, astronomy and atmospheric conditions for take-off and landing at airports. Methods and apparatus include multiple optical sources and a receiver having sub-apertures for detecting light traveling along independent paths from the optical sources to the sub-apertures. The sub-apertures of the receiver are arranged, including relative spacing, to match the geometric arrangement of the multiple optical sources, where there is one sub-aperture for each optical source. Appropriate images received by the sub-apertures are analyzed using differential image motion measurement techniques.
Abstract:
Device and process for smoothing printing screens for silk screen printing, in particular rotary screens, liquid being sprayed at high pressure onto a screen (1, 1′) lying on a compression-resistant and dimensionally stable support.
Abstract:
The present invention relates to a cleaning device for cleaning the back cloth of a printing machine and more precisely a textile printing machine, wherein said cleaning device comprises at least one rotor provided with tines for cleaning the back cloth. The tines of the rotor are traditionally made in the shape of flexible strips. During the operation, said strips abut the back cloth and sweep it on a portion of their length due to the centrifugal force.
Abstract:
A storage system for round stencils, in particular those used in the textile industry, has two or several holders for releasably holding the round stencils. The holders of the storage system may be moved by a drive, preferably all together. Also disclosed is an application system which has besides the production machine and the storage system a separate washing installation for cleaning the round stencils taken from the production machine. In the washing installation, the round stencils are sprayed from the inside and cleaned from the outside, in particular by brushes, at the same time as they are rotated.
Abstract:
A broad textile web, on its way to a processing station such as a rotary-screen printer, passes around a set of closely juxtaposed but independently rotatable feed rollers that are individually driven via respective differential gear trains each having a first input connected to a common drive shaft and a second input connected to an ancillary stepping motor. Each feed roller engages a strip zone of the web which is scanned by an associated sensor upstream of the roller, the latter detecting the leading and trailing edges of recurrent transverse web sections--e.g. of pile fabric--mechanically, electrically or optically distinguishable from intervening sections. Unequal longitudinal tensions in the several strip zones actuate the sensor-controlled stepping motors for different time periods so as to cancel any relative deformation. The lateral edges of a rising web portion are guided between separately driven roller pairs supported by parallelogrammatic linkages which rise or fall according to whether these rollers rotate too slow or too fast in comparison with the web speed, thereby controlling switches which either accelerate or decelerate the corresponding drive motors to keep the web edges straight.
Abstract:
To produce a perforated metal foil, especially for use in a screen printer, a decomposable, dissoluble or vaporizable dielectric substance is deposited on a cylindrical conductive substrate in a dot pattern under the control of a photoelectrically scanned master. The spaces between the dots are then filled with an electrolytically deposited metal forming a coherent layer which is subsequently stripped off the substrate. The deposition of the dot pattern is carried out through a spray nozzle, sweeping the rotating substrate, which has an outlet in a bottom wall of a narrow space filled with the liquid dielectric to be dispensed, that space being separated by an apertured partition from an overlying plenum chamber in which the air is intermittently pressurized by an electromagnetic armature to expel a limited quantity of dielectric through the outlet; the membrane may be vibrated at supersonic frequencies to generate the necessary discharge pressure.
Abstract:
A machine for printing a recurrent pattern on sections of predetermined length of a textile web, comprising a number of parallel rotary-screen printing units spaced apart in the direction of web motion, includes a first sensor for detecting the leading edge of an oncoming web section to be imprinted and a second sensor for ascertaining the passage of a mark indicating the start of a printing pattern on the first unit. The odd-numbered units print the first half of the pattern, in different colors, whereas the even-numbered units print the second half in corresponding colors; between printing operations, the screen of each unit is lifted off the web and can be angularly readjusted to compensate for relative disalignment between the web sections and the printing patterns. Such disalignment is determined by the two sensors whose output signals are translated into command signals sequentially delivered to control inputs of the several odd-numbered units at equal intervals for making the necessary adjustments just before arrival of the leading edge of a web section at these units; the control inputs of the even-numbered units receive these commands at instants delayed with reference to the midpoints of these intervals so that their adjustments take place after that leading edge has passed them. Where the sections to be imprinted are tufted fabric piles, the first sensor comprises two juxtaposed feelers, one loaded by a hard spring and the other loaded by a soft spring; an oncoming pile edge elevates the latter but not the former to cause completion of a signal circuit discriminating against seams in the web which would cause both feelers to be elevated concurrently.
Abstract:
A dyestuff applicator, overlying an area of a movable printing screen through which dyestuff is to be fed to a substrate, comprises a horizontal supply tube which supports an axially extending dyestuff-distributing member with freedom of relative movement in a vertical axial plane of the tube. The distributing member, resting under pressure on the screen, forms a discharge slot communicating with the interior of the tube through a multiplicity of conduits closely spaced along the tube axis, the conduits being disconnectable from the slot with the aid of a slidable or rotatable shutter lodged in the distributing member and controlled by an external actuator mounted on the supply tube.