摘要:
A mold apparatus for liquid injection molding machine which mold is dripless comprising a frame, four support posts mounted on the frame; a conduit for a liquid molding composition slightly mounted on the forward end of the frame having a front end and a rear end; a first plate means having passage means therein for the passage of the liquid molding composition and fixedly mounted on the forward end of said conduit and adapted to slide within support means and within said mold frame means located adjacent to the forward end of said frame, nozzle means at the end of said passage means of said first plate means at the rear end of said mold frame means and away from said conduit means and pin means slidably mounted in said mold frame means adapted to open and close said nozzle means and mold cavity means slidably mounted on said support means adapted to move toward and away from said nozzle means.
摘要:
This invention relates to a molding apparatus capable of producing flashless molded parts due to a perfect surface-to-surface mating of a pair of molds. The molding apparatus comprises an upper holding means for holding at least one upper mold having a path in which a moldable material is passable, and a lower holding means for holding at least one lower mold having a cavity, wherein a certain amount of fluid substance is filled between a bottom surface of the lower mold and the lower holding means, thereby the lower mold being floatable on the fluid substance and movable along the lower holding means, subsequently a joint between the upper mold bottom surface and the lower mold top surface being realized perfectly due to a back pressure of the fluid substance.
摘要:
Composite moulded rubber or plastic articles, each comprising two distinct parts separately formed by injection moulding of different materials and subsequently joined together by vulcanising or the like, are produced in a dual purpose apparatus that simultaneously moulds two separate parts and bonds together two previously moulded parts.
摘要:
Phenolic novolak resins are described which are structurally characterized as having from about 55% to about 90% of the available theoretical paraphenyl linkages in the resin chain bridged to a phenyl group. The resin compositions of this invention provide extended resin stability at relatively low temperatures without significant adverse affect on the cure speed at the molding temperature. The resins are especially suited for use in runnerless injection or cold manifold molding processes, but can also be used in transfer, compression and injection molding processes.
摘要:
A method of making a one piece insert (10) for retaining a plurality of electrical contacts (20) in an electrical connector. The insert (10) includes a plurality of bores or passageways (15) having integral with the insert means for retaining a contact within each of the insert passages. The integral means for retaining a contact (20) includes a plurality of radially deflectable contact retaining fingers (11) adjacent a plurality of ribs (16). Shoulders (17) on the ribs (16) and the free ends (12) of the retention fingers (11) engage forwardly and rearwardly facing shoulders (21, 22) on a contact, thereby captivating a portion (25) of the contact within the insert. The radially deflectable fingers (11) in the insert allow a contact to be inserted and removed from one end of an electrical connector. The method of making the insert includes two mold halves (70, 80) and a core pin (50) mounted to one mold half (70) and a mating core bushing (60) mounted to the other mold half (80) for each passage which is desired. The structure (54, 55) of the core pin (50) which mates with the structure (64, 65) of the core bushing define the shoulders (17), the ribs (16) and the deflectable fingers (11), which are formed in the molding process.
摘要:
A moulding composition comprising (a) a melamineformaldehyde resin having a molar ratio of melamine to formaldehyde in the range 1:1.5 to 1:2.5 which upon hardening is capable of withstanding heating at 200.degree. C concerned for 2 hours in air without causing significant structural damage or color change to moulded articles made from moulding compositions in which it has been incorporated, (b) an accelerator derived from a mono- or dibasic organic acid, (c) an inorganic filler having low adsorption characteristics and an oil adsorption value of 10 to 40, (d) a further inorganic filler and (e) an external lubricant comprising at least one carboxyorganosiloxane esterified with an alcohol containing up to 4 carbon atoms and the process of preparing said moulding compositions.
摘要:
A method of fabricating and mounting a fiberglass fan blade of predetermined configuration which includes the steps of producing a metal hub having a dovetail slot in one end thereof and also having a bore extending from the other end thereof into said slot, assembling a plurality of layers of resin-impregnated fiberglass sheet in superposed relation forming a blade blank of predetermined dimensions, each of said layers including a blade portion and a root portion of a width at least equal to the diameter of said hub, interleaving additional pieces of the fiberglass sheet with the root portions of said layers to increase the thickness of the resulting root portion of the blank to approximately the configuration of the hub slot, inserting the root portion of the blank into the slot, placing the assembled blank and hub in a mold which includes cavities for the blank and the hub and a shoulder at the inner end of said hub cavity, heating the mold until the resin substantially liquifies while maintaining the one end of the hub in seated relation with the shoulder, forcing additional substantially liquified resin and fiberglass material through the bore into the slot until the slot and all spaces between adjacent the layers are completely filled, closing the heated mold at a predetermined rate into fully closed relation with the blank and the hub, and effecting curing of the resin while maintaining the mold closed.
摘要:
A process for producing shaped parts from synthetic and similar workable materials by filling molds under pressure, hardening and removing the articles from the molds. Movable, essentially identical mold carriers are provided with article-related mold inserts preselected for the work cycle and locked in place in the carriers. The forming tool is filled with the synthetic, it is exposed for a given time to certain temperature and pressure conditions, the tool is opened and the inserts are expelled. The form carriers are then outfitted with another set of form inserts while the first set of mold inserts are removed from the molding cycle.
摘要:
A molding apparatus is provided having an interchangeable material feed cylinder selected either for injection molding or transfer molding. The selected material feed cylinder receives the molding material and discharges the same to the cavity mold supporting structure. Displacement means in the form of a dual piston cylinder having a selectively variable stroke is provided for feeding the molding material through the selected material feed cylinder. The apparatus further provides for control means for controlling the length of travel of the displacement means depending upon the material feed cylinder selected for use in the apparatus.
摘要:
A method for molding one piece seamless contoured structures. The mold consists of a hollow, cylindrical mold member whose internal surface area defines the external surface of the piece to be molded, that is adaptive to receive a piston having a reservoir containing a fluid plastic and a mandrel mold member of low melting alloy whose shape defines the internal surface of the molded structure. The piston is forced upward to cause the fluid plastic to flow into the interstices and allowed to cure. Heat is applied to the mold assembly to melt the alloy to allow removal of the contoured structure when the mold assembly is disassembled.