Abstract: A nozzle of a dyestuff applicator has a cylindrical valve housing formed with an orifice obstructable by the tip of an electromagnetically displaceable needle which controls the outflow of dyestuff from a chamber in that housing. The chamber is sealed by a rubber diaphragm which is penetrated by the needle whose shaft is engaged by a pair of parallel membranes of spring steel peripherally clamped in an extension of the housing. Each membrane comprises a narrow outer ring with an inwardly projecting tongue split into two diverging branches which are interconnected at their free ends, near the diametrically opposite side of the outer ring, by a re-entrant web extending radially between these branches and terminating in an inner, needle-supporting ring concentric with the outer ring.

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.

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 substrate to be patterned, such as a textile web, is moved past an array of nozzles with discharge orifices closely spaced from its surface, the substrate being firmly backed at locations confronting the nozzles by being drawn against a supporting conveyor or by being led around rollers. The nozzles are electromagnetically operated by needle valves, the valve needles being carried by membranes under substantially balanced pressures from the printing liquor and from a fluid such as compressed air. The electromagnetic coils are intermittantly energized by a programmed pulse generator with a large but brief driving current followed by a low holding current, the pulse generator including two complementary power transistors in series with a coil winding. A dyestuff applicator carrying one or more of such nozzles may be transversely displaceable across the substrate, under the control of a programmer, between intermittent advances of the substrate in its longitudinal direction.

Abstract: A substrate to be patterned, such as a textile web, is moved past an array of nozzles with discharge orifices closely spaced from its surface, the substrate being firmly backed at locations confronting the nozzles by being drawn against a supporting conveyor or by being led around rollers. The nozzles are electromagnetically operated by needle valves, the valve needles being carried by membranes under substantially balanced pressures from the printing liquor and from a fluid such as compressed air. The electromagnetic coils are energized by a generator of short current pulses separated by a low holding current, the generator including two complementary power transistors in series with a coil winding. A dyestuff applicator carrying one or more of such nozzles may be transversely displaceable across the substrate, under the control of a programmer, between intermittent advances of the substrate in its longitudinal direction.

Abstract: A printing machine with several groups of rotary-screen printing units, designed to print different color components of complementary portions of a recurrent pattern on an elongate web moving continuously beneath their screens, includes a programmer such as a perforated-type reader controlling the operation of the several printing units of each group in timed relationship dependent upon the web speed. A speed changer enables the peripheral velocity of the screens to be set at values different from the web speed, the timing of the printing operations being determined by two speed sensors upstream and downstream of the speed changer. These operations include a lowering of the rotating screen onto the web at the beginning of a printing cycle, a lifting of the screen off the web at the end of a working phase of that cycle, and a stoppage of screen rotation during part of the ensuing idling phase.