SU640848A1 - Hot-channel mould - Google Patents

Description

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 The invention relates to devices for processing into products of polymers, it is mo. It can be used for casting small-sized products, as well as for multi-inlet casting of large-sized products.

The well-known mold for die casting of large-sized products from thermoplastic materials by injection molding, containing a matrix, punch, plates, ejector system, switchgear with heated gating channels 1. In a known form, to reduce heat loss, the nozzles are made self-locking with spring-loaded valves, and supplying the melt to the nozzles installed streamlined spherical plugs.

Also known is the hot-channel casting mold containing a chamber made in the form of a casting plate with parting channels, at the ends of which there are plugs, thermoelectric heaters and point nozzles placed in the casting plate, a matrix plate with pre-chamber bushings installed in it, a plate of punches and an ejection system 2

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In this form, a system of pre-inlet inlet is used, in which for preserving-. In the case of plastic material, the nozzle should receive as much heat as possible. Heat transfer from the heating elements to the nozzles is through a gating 3 such a kedostatomna form, since the hot elements are located at a considerable distance from the nozzles, despite the fact that the nozzles are made of a material with good heat conduction properties, they are not sufficiently heated. Therefore, it is possible for the press material to harden in the area of the inlet. Increasing the heating temperature of the gate valve by increasing the power of the heating elements c. the purpose of transferring more heat to the nozzles is impractical because it leads to overheating of the press material located in the pasBo Hmnx channels and to the deterioration of its cBoiicTn.

Claims (2)

The purpose of the invention is to reduce heat loss by improving the heating of the nozzles. The goal is achieved by the fact that in the casting plate, the heater passes from the zone of thermoelectric heaters to the zone of the installation of point nozzles, heat conductive channels and annular grooves, covering nozzles, are filled with a material with heat conductivity, greater thermal conductivity of the material of the casting plate. FIG. 1 shows the proposed form, the overall appearance; in fig. 2 - section A-A of FIG. 1. The hot runner casting mold contains a lithica-like slab i with a splitting out of the canadaal 2, at the ends of which there are 3 having inclined cut ends. Electric heaters 4 are placed in the holes of the gating plate, and dotted nozzles 5 are fixed in the threaded holes. Thermally conductive channels are made in the gating plate, the duct from the ZONE of the heaters 4 is positioned in the installation zone of the dotted nozzles 5, filled with thermal conductivity, greater thermal conductivity of the material of the gating plate, and annular grooves 7 covering the nozzles 5, communicating with the channels 6 and filled with the same material that contacts the dotted nozzles. The form also contains a plate of 8 dies with design sockets 9 ,. pre-chamber sleeves 10 located in the matrix plate, sealing rings 11, plit with punches 12 and an ejection system, made in the form of ilites 13 with AND pushers connected to the removal plate 15, and an emphasis 16. The gutter plate, i, is fixed on the plate 8 matrices using the latch 17 and bonded with her vitamin 18. The form works as follows. After locking the molds, a mold follows, in which the press material from the material cylinder of the injection molding machine enters the dilution channels 2 of the runner plate 1 and then through the dotted nozzles 5 and the pre-chamber sleeves 10 - into the design slots, fill them. After the required shutter speed, the nozzle of the injection molding machine - (not shown in the drawing) departs from the mold. At the same time, the material retains its plastic state due to the heat released by the heaters. Then, when the movable part of the mold is moved, the stop 16 pushes against the stationary support of the machine and acts through the plates 13 and the pushers 14 onto the plate 15 of the die, which removes the finished products from the punches 12. The mold again closes and repeats. Additional channels of heat are transferred from thermoelectric heaters to nozzles through channels 6 and annular grooves 7 filled with material with heat conductivity greater than the thermal conductivity of the sprue plate from thermoelectric heaters to nozzles, since heat loss in channel material b and grooves 7 is smaller. what's up with at the same site in the runner plate. The press material, located in a coil, surrounded by a ring channel 7, receives a large amount of heat without increasing the heating of the runner plate. This provides the possibility of normal operation of the form, excluding the freezing of the material in the inlet sprues of the pre-chamber bushings. The execution of the ten-conducting channels If of the annular grooves in the gating plate and filling them with a material with thermal conductivity, greater thermal conductivity of the gating plate, ensures a stable working-. bot. forms without blocking the inlet orifices and eliminates their stripping, as well as {detrimental to the quality of the press material, since it eliminates its overheating in the ductwork of their channels by eliminating the need to increase the heating temperature of the runner plate, which also creates the possibility of energy saving. In the proposed form, due to improved heating of the material in the inlet zone, the latter can be performed with a x5us toward the point nozzle, then the sprue will be separated precisely - ° plane of the connector without residual heights, which will improve the quality of the product. Point nozzles previously made from be-. corilly bronze can be made of cheaper materials, for example the Formula of the Invention Hot and channel casting mold, containing a chamber made in the form of a sprue plate with distributing channels along. the ends of which are fitted with plugs, thermoelectric heaters and point nozzles placed in the sprue plate, a matrix plate with ancestor installed in it, hero bushings, a plate of punches and an ejection system, so that, in order to reduce heat loss by improving the heating of nozzles, in the gating plate there are made passing and, h areas of thermoelectric heaters in the installation zone of the point nozzles, the heat supply channels and annular grooves, covering the nozzles, filled with heat-conductive material awn greater than the thermal conductivity of the sprue plate material. Sources and formations taken into account in the examination:. Author's certificate number 234644, cl. In 29 C 1/00, 1969. 2. Manikhin Yu. L. “Multi-cavity automated injection molds for thermoplastic products. Leningrad House of Scientific and Technical Propaganda. L., 1970, p. 20-23, p. 14. .g