摘要:
An apparatus for forming contact lenses, wherein front curve mold halves are filled with a hardenable transparent material, such as a polymerizable hydrogel, and back curve mold halves are coupled to the front curve, therein forming a lens. More Particularly, the apparatus includes a conveyor means for transporting pallets of mold halves to the apparatus, an array of piston structures for raising and aligning the back curves with respect to the filled front curve halves, reciprocating means for reciprocating the piston array to couple pairs of front and back curves, and a vacuum chamber and vacuum drawing means for maintaining a vacuum around the curves during coupling. In addition, there is provided individual spring biasing to each reciprocating element whereby sensitivity to thickness variations and pallet misfeeds may be minimized. Further, there is provided a vacuum sleeve, through which the pistons reciprocate within the vacuum chamber, which sleeve preserves the vacuum within the chamber.
摘要:
Le procédé de fabrication d'objets en matière plastique comprend une étape d'extrusion continue d'un matière plastique à au moins un poste d'extrusion déplaçable ou fixe. Ledit procédé comprend en outre :
une étape intermédiaire de répartition constituée d'une part, par un préformage de manière à obtenir une préforme (10) autour d'un noyau (7) allongé et en déplacement par rapport audit poste d'extrusion (12) et d'autre part, par une mise en place de ladite préforme (10) au droit d'au moins un poste de pressage (11), ladite préforme (10) étant supportée par ledit noyau (7), et une étape de pressage séquentiel de ladite préforme (10) audit poste de pressage (11), lequel poste de pressage (11) est déplaçable ou fixe, et destiné à la mise en forme.
Application à la fabrication de pièces ou de profilés en matière plastique de récupération.
摘要:
The invention relates to decorative plaques and emblems, and to methods of making the same. In one embodiment, a decorative emblem (10) is formed by insertion of a decorative foil shape (18) into a preformed bezel (12) and encapsulating and bonding the foil to the bezel with a fluent, curable plastic material (14). After an initial casting of a measured amount (16) of plastic onto the base of the bezel, the foil (18) is inserted and seated. A second cast (20) of plastic forms a cap contiguous with the sides of the bezel and encapsulates the foil and bonds it within the bezel. Upon curing, the plastic cap gives a lens effect to the decorative emblem.
摘要:
Various embodiments related to three dimensional printers, and reinforced filaments, and their methods of use are described. In one embodiment, a void free reinforced filament is fed into an extrusion nozzle. The reinforced filament includes a core, which may be continuous or semi-continuous, and a matrix material surrounding the core. The reinforced filament is heated to a temperature greater than a melting temperature of the matrix material and less than a melting temperature of the core prior to extruding the filament from the extrusion nozzle.
摘要:
A head assembly for an extrusion-based 3D printer includes : a fluid-dispensing head having a manifold and at least two fluid-dispensing nozzles, as of different sizes, which are mounted in communication with a melt chamber in a manifold. Outlets of the nozzles are each closed by a respective valve member. A rocker serves both to pivot the nozzles to their lowermost nozzle-operating position and to actuate the valve members, allowing ready switching between the valves, such that the small nozzle can be used for high resolution work, and the large nozzle for bulk infill.
摘要:
A dosage device (999) for extruding a monocomponent or bicomponent polymeric product, particularly for an automatic machine (1000) for forming a spacer frame, comprising a first dosage assembly (400) and a separate second dosage assembly (500) for the dosage and feeding of the product, which can be activated, in a first feeding step and in a third feeding step, alternately so that one of them provides continuity of flow to an extrusion nozzle (301) while the other one is in the reloading step; the first and second dosage assemblies (400, 500) can be activated, in a second swapping step that is intermediate with respect to the first and third feeding steps, simultaneously and jointly, one of them having a flow-rate ramp that passes from the steady-state value to zero and the other one complementarily having a flow-rate ramp that passes from zero to the steady-state value.
摘要:
A liquefier assembly (20) for use in an additive manufacturing system (10), which includes a liquefier tube (58), one or more heater assemblies (56a, 56b) in contact with the liquefier tube (58), and configured to heat the liquefier tube (58) in a zone -by-zone manner, preferably one or more thermal resistors (60a, 60b) disposed adjacent to the heater assemblies (56a, 56b), and preferably one or more sensors (66) configured to operably measure pressure within the liquefier tube (58). The one or more heater assemblies (56a, 56b) may be operated to provide dynamic heat flow control.
摘要:
Plastic powder/dust is cyclonically pulled into the loading chamber by vacuum. The finer dust rises due to the flow of air upwardly through a separation chamber, and a coaxially arranged intensifying chamber communicates with the lower portion of the loading chamber by a tube that recovers the finer dust. At least two filters between the vacuum unit and the separator, are sequentially activated during phases of successive cycles, so the inactive filter can be cleared of dust by admitting ambient air so the cleared dust is delivered to the loading chamber. Multiple miniature cyclonic separators are provided atop the primary loader in a version without filters.
摘要:
The invention relates to a machine (10) for an automated filling of a mold assembly (1) for molding an ophthalmic lens, comprising: - filling means (20) to fill the mold assembly with a molding material through a filling aperture (6) provided in the mold assembly, - acquiring means (70) to acquire an input value (W1) linked to the internal volume of the mold assembly, and - control means (40) for controlling the flow rate of molding material injected by the filling means in the mold assembly according to a flow rate profile (FR1, FR2) deduced as a function of said input value.