SU361889A1 - CASTING FORM - Google Patents

Description

one

A well-known injection mold for the manufacture of products with nodular materials, containing non-moving and moving forms, composite notions, each of which consists of a series of segments, located around a rod fixed on a fixed-shaped form, the matrix, guide columns and ejectors. However, in such a mold it is difficult to get a product with an increased length and depth of undercut.

The proposed casting mold differs from that known in that the segments are made in the form of an L-shaped square moved along the guides located on the fixed half-form, with a hole on one side of it, which includes a wedge column mounted on the fixed half-form, and each pair of diametrically located The segments have cutouts in the area where the sides of the square are modified, allowing the segments to move to the center of the core of the punch when the shape is opened. This makes it possible to manufacture products with an increased length and depth of undercuts.

FIG. 1 shows the shape of the item; in fig. 2 is the same; the section along A-A in FIG. one; in fig. 3 is the same; the section along BB in FIG. 2; in fig. 4 - arrangement of the segments of the composite punch in a closed injection mold; on

FIG. 5 - the location of the segments of the composite punch when opening the mold.

The form consists of three main parts. The first part is nlita /, which

Krenits to a motionless plate of an automatic molding machine. An auxiliary plate 2 is placed on the plate / in which the rod 3 is installed, the wedge columns 4 and 5 and the guide columns b centering all three parts

forms. The second part of the form includes a plate 7, which serves as the basis for fastening the strips 8 II 9 n of the liner sleeve 10. These nanolks and the body of the sprue sleeve are used as guides for L-shaped

segments // and 12, located around the rod 3 composite punch. The third part of the form includes nlita 13, which is attached to the movable plate of the thermoplastic automat. On the plate 13 there is an ejector of the part in the form of a sleeve 14 and semi-walls 15 for shaping the outer surface of the part 16. The wedge columns 4 and 5 are a rod consisting of a head for fastening in the plate 2 of a straight section for

providing the exit of the rod 3 from the hole of the composite punch, the wedge part, which serves to prevent the L-shaped rods of the straight end to fix the segments, with the beginning of the wedge part of one type

columns slightly higher than the other, that

makes it possible to ensure the order of movement of the petals.

The composite punch is made in the form of an assembly assembled from two types of L-shaped segments // and 12 placed around the rod 3. The segments are L-shaped squares moved along the guides 8 and 9 placed on the movable half-form. The horizontal section 17 of one of the sides of the square has an opening 18 where the wedge column enters. The vertical side 19 of the square on the outer surface is provided with a profile that defines the undercut (for example, the thread on the product), and the inner surface is smooth and corresponds to the outer surface of the rod, with which it is in conjunction when the mold is closed. Each pair of diametrically located segments is provided in the area of change in the direction of the sides of the square with notches 20 and 21, which ensure the movement of the segments to the center of the rod 3 when the shape is opened.

Casting form works as follows.

After injection of the plastic through the sprue bushing 10 into the forming cavity and the subsequent solidification of the part, the movable plate of the thermoplastic automated machine begins to move away, taking the third and second parts of the mold. In the process of withdrawal of the second and third parts, the rod 3 leaves the space formed by the inner surface of the sides 19 of the segments 11 and 12. After this, the wedge column 5 moves the segments 11 to the center, and then the wedge columns 4 move the segments 12 in the same direction (as

this is shown in FIG. five). With their ends, the wedge columns fix the segments in the folded state. At that moment, when the segments of the composite punch are folded and fixed, the departure of the second part of the mold ceases. The third part of the form continues to move away. At this time, the folded segments emerge from the part, and the semi-matrix 15, apart, release the outer surface.

details 16. In the process of waste of the third part of the mold, the ejector sleeve 14 resets the product 16.

Subject invention

A mold for the manufacture of articles with an undercut of polymeric materials, containing fixed and movable half-molds, composite punches, each of which consists of a series of segments arranged around a core fixed on the fixed half-form, dies, guide columns, ejectors,

that, in order to manufacture products with increased length and depth of the undercut, the segments are made in the form of an L-shaped square moved along the guides, located on the movable half-form, with a hole on one side, which includes a wedge column, mounted a pair of diametrically located segments has cutouts in the area of changing the direction of the sides of the square, which ensure the movement of the segments to the center of the core of the punch when the mold is opened.

Fig 2

Fig.Z

Fi.GL

5