SU1654002A1 - Mold for making undercut parts - Google Patents

Abstract

The invention relates to the field of plastics processing, in particular to the injection molding of products from thermoplastic materials. The purpose of the invention is the expansion of technological capabilities by molding articles with a transverse blind bridge. According to the invention, the form comprising a composite punch consisting of two parts, one of which is made in the form of a sleeve with a conical outer surface, and the other in the form of a glass with an internal conical surface mounted by means of a rod on the sleeve with the possibility of limited movement and contact with the conical the surface of the sleeve, and the elastic sign in the form of a ring mounted on the conical surface of the sleeve, provided with an additional composite punch with a sign installed oppositely and co clear to the first punch. In this case, the cavity of each sleeve of the punches communicates with the compressed air supply system, and at the end of the rod located in the cavity of each sleeve, a piston is mounted, which is spring-loaded in the axial direction relative to the sleeve. When compressed air is fed into the cavity of the sleeve of the composite punch, the spring is compressed, spring-loaded the cup relative to the sleeve, and the product undercut opens the parts of the punch by an undercut. Here, the elastic sign is compressed and exits from the undercut of the product. 3 il.

Description

This invention relates to the injection molding of articles made from thermoplastic materials.

The chain of the invention is the expansion of technological capabilities by ensuring the manufacture of products with a transverse dividing wall.

Figure 1 shows the casting form, a general view; 2 and 3, an undercut forming sign, respectively, in a closed (locked) state and at the beginning of the opening.

The casting foom contains mounting plates 1 and 2 (Figs. 1 and 2), with the help of which it is mounted on the injection molding machine, plates 3 and 4 with coaxially arranged in them composite forming undercuts punches, each of which consists of two parts, one of which is made in the form of a sleeve 5 with a conical outer surface at the end, and another in the form of a glass 6 with an internal conical surface mounted by means of a rod 7 on the sleeve 5 with the possibility of limited movement due to the installation of a spring-loaded piston 8 at the end xial direction relative to the sleeve 5, and on the conical surface of the sleeve 5 has an elastic sign 9,. made in the form of a ring. The form also contains a plate 10, a matrix 11. a system of plates 12-14, pushers 15 fixed in

WITH

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plate 13, guide columns 16. pressed into plate 4, counter pushers 17 and gate spreader 18 fixed in plate 14, rods 19 fixed in plate 14, disc plate 20, sprue bushing 21 and two support beams 22. Cavity of each sleeve 5 communicated by channels 23 with a compressed air supply system. The pistons 8 are spring-loaded relative to the sleeves 5 by the springs 24.

The form works as follows.

The form is shown (FIG. 1) at the time of injection of the thermoplastic material. At the end of the injection and holding time for cooling the parts, the mold connector and the extraction of finished products begin. Before opening the mold, after injection and cooling, the sleeve 5 enters the cavity through channel 23 and compressed air is supplied under pressure. The movable plate of the injection molding machine with the plate 2 fixed on it (FIG.) Begins to move to the left. 2 plates 4 and 12 attached to the plate begin to move to the left, bars 22, plate 10 Latrice. At the same time, plates 13 and 14 move to the left, which are planted on columns 16 with the possibility of moving along them. Since the plate 3 with the elements fixed on it remains stationary, at the initial moment there is a separation of the gate at the right end of the gate sleeve and its removal from the sleeve with further movement of the movable part of the form.

At the same time in the cavity of the sleeve 5, fixed in the plate 3, serves compressed air. Under the action of compressed air acting on the piston 8, the spring 24 is compressed and, as the matrix plate 10 moves, the undercuts protrude through the elastic sign 9 open the composite punch, moving the cup 6 relative to the sleeve 5. The elastic sign 9 slides along the conical surface of the punch. diameter and out of undercut.

During the connector of the composite punch, the air pressure neutralizes the spring force, removes the force effect on the elastic sign 9.

Upon further disclosure of the form of the punch, fixed in the plate 3, out of the internal cavity of the product. After that, air pressure is applied to the cavity of the sleeve 5. fixed in the plate 4. The piston 8 (Figures 2 and 3) moves to the right, compressing the spring 24, moving the cup 6 relative to the sleeve 5. through the blank wall displacing the product from the matrix 11, thereby providing tearing it away from the sprue. Upon further movement of the movable part of the form to the left, the disk 20 comes into contact with a fixed stop (not shown), with the result that the plates 13 and 14c are fastened with elements (the pusher 15,

the counter pushers 17 and the dumper 18) stop. The plate 2, the plate 4 with the punch, as well as the plate 12 and the plate 10 of the dies with the dies 11 continue to move to the left. End of the product, pushing the pusher

15, is moved out of the matrix 8. The undercuts protrusions move the elastic mark 9 released from the force of the spring 24 along the conical surface of the sleeve 5. Under the action of elastic forces the elastic mark 9

decreases in diameter and exits from the undercut.

At the same time, the gate ejects with the ejector 18. As the stroke of the moving part of the mold is selected

the molded articles and the sprue are separately removed from the mold. Next, the pressure of compressed air is released from the cavities of the sleeves 5 and the cups 6 under the action of the springs 24 are moved to the sleeves 5, elastic

marks 9 are clamped between the ends of the sleeves 5 and the cups 6.

After that, the movable part of the mold is moved to the right and, after closing, the mold is ready for the next cycle.

Claims (1)

Invention Formula Casting mold for the manufacture of products with undercuts containing a system movable and fixed plates, installed in them a matrix and a punch consisting of two parts, one of which is made in the form of a sleeve with a conical outer surface at the end, and the other in the form of a glass with an internal conical surface mounted by means of a rod on the sleeve with the possibility of limited movement and contact with the conical surface of the sleeve, and elastic a ring-shaped sign mounted on the conical surface of the sleeve, characterized in that, in order to expand technological capabilities by ensuring the manufacture of products with a transverse blind partition, it is provided with an additional punch with a sign installed oppositely and coaxially with the first punch, while the cavity each sleeve communicated with the feed system compressed air, and at the end of the rod, placed in the cavity of each sleeve, installed piston, spring-loaded in the axial direction relative to the sleeve. l-gpf G 6 9 6 S L 9 L U 9 years QI ЈZ 91 Ј1 And 5 2 $ Z32 Ws NNfcS N S X shzhsha eight 24 7 AT 2Ts 7 Fig.Z FIG. 2