Abstract: The invention relates to a storage head for a blow moulding machine for discontinuous manufacture of multi-layer co-extruded and blow-moulded hollow bodies made of thermoplastic. To improve the product quality and to increase the throughput, each distributor element is designed as a spiral channel distributor (20) which distributes the individual molten plastic streams uniformly at the periphery. The ejector (14) consists of at least two concentric tubular pieces (42, 44, 46) and the peripherally distributed plastic streams issue from the front face of the ejector (14) and unite to form a single multi-layer flexible plastic tube in the storage space (16) in the storage head housing (10) below the ejector.

Abstract: The invention relates to a process for driving printing elements of a dot matrix printer in which the matrix dots to be printed are to be thinned out without any thin lines, in particular steeply inclined thin lines, being lost. To this end, before thinning out each matrix dot to be printed is associated with another matrix dot disposed on a nearest neighbor grid point in a certain direction of addition. After thinning out, the respective characters or images are printed sufficiently well and clearly. The process is intended for use in dot matrix printers.

Abstract: The disclosure relates to novel dopamine derivatives of general Formula I ##STR1## wherein A is a substituted phenyl residue of the structure ##STR2## wherein R.sup.1 and R.sup.2, being identical or different, mean hydrogen, C.sub.1-15 -alkyl and allyl,D is ##STR3## R.sub.4 is hydrogen, C.sub.1 -C.sub.4 -alkyl, CF.sub.3, NH.sub.2 E is ##STR4## X is OH, NH.sub.2, ##STR5## and NH--SO.sub.2 --CF.sub.3, if Y=OH, Y is OH, NH.sub.2, ##STR6## NH--SO.sub.2 --CF.sub.3 and NH--SO.sub.2 --CH.sub.3, if X=OH, but wherein X and Y do not simultaneously mean OH, with R.sup.3 being C.sub.1-4 -alkyl, andZ is H or OH, and, if Z means the hydroxy group, the residue A can also be present in the tautomeric basic form,and their acid addition salts, their preparation, and use as medicinal agents having antihypertensive activity.

Abstract: The sealing and cleaning apparatus for an ink head consists of an electromotively driven endless band, on which two wedge-shaped wiping lips are arranged. For cleaning and sealing, the nozzle head is brough a close distance in front of the endless band, a surface of the endless band not provided with wiping lips serving as spraying surface for the squirting-out of the ink head. A cleaning device of wiping edge or cleaning roller removes the ink on the endless band. For covering in breaks in recording, the endless band has, furthermore, a depression formed by bulges, which is brough into contact in front of the nozzle plate or covering. For sealing, a convexly formed flexible pad, which is arranged between the endless belt, is pressed by means of a pressure-applying device against the endless band and cosequently against the nozzle plate. Due to the convex form, no air entrapment can occur in the region of the nozzle plate.

Abstract: An ink writing head comprising ink ejection channels and piezoelectric transducer elements allocated to the ink ejection channels, these transducer elements being supplied with writing fluid via supply lines, contains transducer elements comprising a first piezoelectrically excitable layer and a supporting layer firmly joined to the excitable layer. The piezoelectrically excitable layer comprises deflectable regions that are respectively subdivided into a peripheral and into a central region. For generating the needed excursion of the membrane, the regions of the membrane are driven such that the peripheral region is shortened, preferably by transversal contraction, and the central region is lengthened.

Abstract: A gas bearing is formed of a bearing member of sintered material. Sintered grains of a layer forming a desired bearing surface are deformed into the shape of a honeycomb in non-cutting fashion and are subsequently finely worked in cutting fashion, so that super-fine pores formed at corners of the honeycomb arise and which form nozzles.

Abstract: An annular exit die for an extrusion head of the type having a die casing ring and a tapered die core cooperating to form an annular die gap or orifice for fabricating a hollow extrudate of thermoplastic material. The tapered die core is adjustable in the axial direction and changes the radial cross-sectional dimension of the die gap as a function of its position. The casing ring has a lower end and an inner wall defining the outer boundary of the die gap. The wall has a step at the lower end of the ring. The step has an inner radially undulating circumferential profile and a radially undulating edge defining the boundary between the step and the lower end of the casing ring. The inner wall of the ring also has another step disposed radially inwardly of the first-mentioned step. This step has an inner radially symmetrical profile and a radially symmetrical edge defining the boundary between the two steps.

Abstract: In an axially extending extruder head for producing a thermoplastic tubular member, the material to be extruded is first supplied into a pair of annular first passageways spaced apart in the axial direction of the head, these passageways extend obliquely of the head axis. From the first passageways the material enters an axially elongated annular second passageway extending between the two first passageways. An annular third passage, extending transversely of the head axis, conveys the material from the second passageway into an axially extending feed passageway from which the material is extruded through the nozzle end of the head. The first, second and third passageways can be located in different parts of the extruder head.

Abstract: In order to separate boards of wood or the like from one another in a stack, spacing strips are successively lifted from a hopper by a rising flight conveyor and are accumulated on a generally horizontal extension of that conveyor for consecutive pickup, at predetermined instants of an operating cycle of a stacker, by a transfer mechanism delivering each strip to a passing gripper on a continuously moving transport band overlying the stack. A vertically movable frame beneath the transport band, positioned above a stacking platform, carries a series of unloaders normally projecting into the path of the oncoming strips for dislodging them from their grippers and depositing them on a board already resting on the platform as part of a growing stack. The unloaders can be selectively deactivated to vary the number and/or the spacing of the strips deposited on the top of the stack.