SU660847A1 - Moulding head - Google Patents

Description

I

The invention relates to devices for the processing of plastics, it can be used to obtain foamed products from polymeric materials by injection molding with saturation of the iio; uiMepa melt by a gas-forming agent.

The known casting head for the manufacture of products from foamed polymeric materials, inclusive, 1a injection cylinder with a nozzle, a device for supplying a gas-forming agent and a mixing chamber | 1. A disadvantage of the known injection head is the low productivity of the foaming process and an increase in polymer consumption due to the additional volume of the mixing chamber.

The known injection head for manufacturing products from foamed polymeric materials includes an injection cylinder with a nozzle and a device for supplying a gas forcing agent 2. The last of the indicated injection heads is closest to the one proposed. The disadvantage of such a die head is the low productivity of the foaming process and an increase in polymer consumption.

The purpose of the invention is the intensification of the foaming process and the reduction of polymer flow 11. This goal is achieved 6, ia year to the fact that the device for the supply of gas porous, made in the form of a tip from porous to material such as metal-ceramic, rigidly mounted on the corus in front of the nozzle, forming a mixing chamber with it.

FIG. 1 shows a die head; -; positioning the tip to simultaneously saturate the polymer melt with the aorifier; in fig. 2 - casting go.yuvka with the location of the tip for the counter-saturation of the polymer melt with a gas-oxygen former; in fig. 3 - casting head with tip location for passing and oncoming saturation of a polymer melt by a gas-forming agent.

Claims (2)

The injection head contains a tip 1 made of a porous material, such as metal-ceramic, rigidly mounted on the housing 2, a nozzle 3, a mixing chamber 4 formed by the inner surface of the nozzle 3 and the outer surface of the tip 1, the channel A for the gas forming agent, the channel B for feeding the polymeric material . The injection head for manufacturing products from foamed polymeric materials works as follows. At the time of filling the mold (not shown) with a molten polymer material, a gas former (nitrogen, freon) is fed through the channel A under pressure. The gas exiting the porous tip 1 uniformly saturates and actively mixes with the melt of the polymer material, which ensures the formation of a homogeneous structure of the foam material. In addition, in the mixing chamber 4, the gas is displaced with the melt over the entire contacting surface of the tip 1. The formed foamed polymeric material continues to fill the mold. After removing the product from the mold, the cycle is repeated. The proposed die head is simple and economical compared to the known ones. In this injection head, the contact area of the polymer melt material with gas increases, since its saturation occurs over the entire surface of the tip, which intensifies the foaming process. In addition, there is no need to equip each injection mold with a sealed mixing chamber, two injection nozzles with locking devices and a control system for them, which simplifies the design of the head. An Injection Molding Head for manufacturing products from foamed polymeric materials, including an injection cylinder with a nozzle and a device for supplying a gas-forming agent, characterized in that, in order to intensify the foaming process and reduce polymer consumption, the device for supplying a gas-forming agent is made in the form of a porous material tip the type of metal-ceramic rigidly mounted on the body in front of the nozzles and forming a mixing chamber with it. Sources of information, taken into account during examination 1. French Patent No. 2255160, cl. On 29 D 27/02, 1974. 2. The patent of Germany No. 2053646, cl. On 29 D 27/00, 1975. /P