Abstract:
Film heater apparatus and method for heating a melt channel in a molding device includes structure and/or steps whereby a first dielectric layer is disposed on a surface of a substrate. An active heating element is disposed on the first dielectric layer, the active heating element being configured to generate heat to heat the melt channel. The active heating element has contact terminals arranged to support an electrical connection to the active heating element. A second dielectric layer is disposed over the active heating element, but not covering the contact terminals, thereby permitting coupling of the heater element to an electrical supply.
Abstract:
A nozzle for an injection molding apparatus is provided. The injection molding apparatus has a mold component that defines a mold cavity and a gate into the mold cavity. The nozzle includes a nozzle body, a heater, a tip, a tip surrounding piece and a mold component contacting piece. The nozzle body defines a nozzle body melt passage therethrough, that is adapted to receive melt from a melt source. The heater is thermally connected to the nozzle body for heating melt in the nozzle body. The tip defines a tip melt passage therethrough, that is downstream from the nozzle body melt passage, and that is adapted to be upstream from the gate. The tip surrounding piece is removably connected with respect to said nozzle body. The mold component contacting piece is connected with respect to the nozzle body. The material of the mold component contacting piece has a thermal conductivity that is less than at least one of the thermal conductivity of the material of the tip and the thermal conductivity of the material of the tip surrounding piece.
Abstract:
The present invention generally relates to an injection molding apparatus, comprising a manifold including a plurality of manifold channels and a plurality of nozzles. Each of the nozzles defines a nozzle channel in fluid communication with one of the manifold channels and including a plurality of nozzle bodies coupled in tandem by a removable and secure connection. The nozzle bodies include at least a upstream nozzle body and a downstream nozzle body. The upstream nozzle body has an upstream end adjacent said manifold channel, and the downstream nozzle body has a downstream end adjacent a mold plate. A removable nozzle tip is retained in a downstream end of each downstream nozzle body. The nozzles also include a plurality of heaters, wherein at least one heater is embedded into each nozzle body.
Abstract:
According to the present invention a coding plate is interspersed between first and second respective inlet and outlet cross over nozzle parts. The cooling plate engages ends of the cross over nozzles during mould filling and provides a melt transfer passage therebetween. Once the mould is filled, the cooling plate acts to dissipate heat from the melt transfer passage thereby promoting solidification of melt therein. Accordingly melt solidification in the sprue is assured with more certainty than prior art designs enabling relatively fax mould cycling with minimal risk of drool.
Abstract:
Auxiliary end heating devices on an elongated, heated hot melt distribution manifold body assist in maintaining uniform temperatures throughout all portions and passageways of the manifold body. The heating devices preferably take the form of thick film electrical resistive heaters of plate-like construction. The end heaters are on their own control circuit separate and apart from the circuit for other heaters for remaining portions of the manifold body. Special isolating slots are formed in lower corners of the manifold body between supporting standoffs and overhead melt passageways in the manifold body.
Abstract:
In an injection molding machine, a fixed platen 2 is provided with an air cylinder 11 through a bracket 13 and a nozzle touch plate 10 is coupled to an end of a piston rod 12 of the air cylinder 11. The piston rod 12 is extendably and contractedly driven so that the nozzle touch plate 10 is moved forward and backward between a closed position where the tip opening 9a of the nozzle 9 can be closed and a retreated position where the opening 9a can be opened. On the nozzle touch plate 10, a spherical recess portion slightly larger in radius than the tip sphere of the nozzle 9 is formed as an abutment portion 10a, and a heater 14 for adjusting the temperature is disposed in the nozzle touch plate 10. Alternatively, a passage may be formed in the nozzle touch plate 10 so that a medium of an optimum temperature can be circulated and supplied.
Abstract:
A method for mold heater startup and sequencing detects the heater zones associated with greater mass and allows them to heat up before zones of lesser mass, thereby reducing wear of the associated mechanical components and minimizing degradation of plastic material. The zones of smaller mass are kept at minimal temperatures until the zones with greater mass reach a set point. The system is capable of detecting multiple levels of thermal load and provides appropriate sequential startup of the identified thermal loads. The operator may also manually program the system to override certain automated sequences in order to ensure an optimal startup sequence. The sequencing of power application to large heaters also minimizes the peak current draw of the system.
Abstract:
A nozzle assembly for use with injection molding apparatus includes an outer sleeve having a relatively large bore extending from an open rearward end forwardly to a substantially closed forward end, and having an injection orifice therein. An inner nozzle tip is located within the sleeve, and has a radial flange and an internal extending from a rearward open end to a forward tip having a plurality of flow orifices upstream of the injection orifice. A manifold insert is located within the outer sleeve and includes a through bore in axial alignment with the bore of the nozzle tip. The manifold insert has a forward end which receives the nozzle tip and which abuts the radial flange. A coil heater is located radially between the manifold and the outer sleeve, a forward end of the coil heater seated on the radial flange. The manifold insert, nozzle tip and coil heater form a subassembly which is easily removed and reinserted vis-a-vis the outer sleeve.
Abstract:
A die for injection molding for charging molten resin onto a surface material set on the cavity surface is disclosed. The die comprises direction changing means for changing the direction of flow of the molten resin charged through the gate to directions along the surface of the surface material. The direction changing means may be a substantially conical direction changing member for changing the direction of flow of the molten resin. Since the direction changing means can change the direction of flow of the molten resin charged into the die, which is completely closed or slightly open, to directions along the surface of the surface material, the molten resin does not strike the surface material. Thus, damage to the surface material in the neighborhood of the gate can be prevented, and the surface material can be protected against the collision with molten resin which is at a high temperature and under a high pressure.
Abstract:
A cylinder temperature controller for an injection molding machine in which an injection molding operation is performed while keeping the injection cylinder at a stable preset temperature regardless of disturbances such as the change of mold temperature or ambient temperature and the temperature rise caused by the shear compression of resin. A temperature regulator for carrying out PID feedback control of the injection cylinder temperature is provided with a PID adjusting means unit for automatic tuning. The actual temperature T of each portion of the injection cylinder is detected by a thermocouple. When the actual temperature T deviates from a predetermined temperature range defined by an upper limit [A+B] and lower limit [A-B] which are set on the basis of the preset target temperature A, an automatic tuning command is outputted to the temperature regulator. Upon receipt of this command, the PID adjusting unit sets the PID parameters again at a value suitable to the disturbance. By keeping the PID parameters to be suitable to the disturbance, the actual temperature T of each portion of the cylinder agrees with the preset target temperature A regardless of the change of the disturbance.