SU1765006A1 - Plastic materials moulding press - Google Patents

Abstract

Use: production of construction ceramics, namely, production of I, T hollow ceramic brick by plastic pressing. SUMMARY OF THE INVENTION: A plastic press comprises void formers installed at the outlet of an arc chamber of varying cross section, formed by an arc brace, side discs and a forming drum. New in the press is the attachment of hollow cores to arc holders, the middle part of which fits into the annular grooves of the forming drum, and the ends are fixed to the supporting structure of the press. The arc holders grab the forming drum on an arc with an angle of not more than 180 °. 3 il.

Description

The invention relates to equipment for the production of building ceramics, in particular, to presses for the production of hollow, ceramic bricks by plastic molding.

Screw presses are known for the production of hollow ceramic bricks by plastic molding. In these, the core holders are fixed at the exit of the pressing chamber, where the mass is formable and is pumped by a screw blower.

One of the main drawbacks of such presses is the low quality of the molded products due to the presence of numerous defects in the structure of the molded beam - the so-called twisted. Structural defects manifest themselves in the form of micro- and macrocracks, which reduce the strength of a brick in compression and, especially, in bending.

A known plastic press design, selected as a prototype, containing hollow cores. installed at the outlet of the arc chamber of pressing a variable section formed by an arc bracket, side discs and a forming drum. Here, the core holders are fixed on an arc bracket fixed on the supporting structure of the press. Such a press, in contrast to a screw press, makes it possible to obtain a bar with a smaller number of structural defects.

However, when molding a hollow brick, defects may appear that are a consequence of the formation of stagnant zones at the place of attachment of hollow cores to the arc brace. These elements, the forming drum and the disks, are removed from this place. The stationary arc bracket itself is an element that inhibits the movement of clay along the chamber and creates a certain gradient of flow rates of the formable mass over the cross section of the chamber. If the hollow cores are attached to the bracket, then they will inevitably form a zone where

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clay is not moving. This zone, occupied by some part of the cross section of the chamber, serves as a kind of cork, which, if any, the flow of clay loses continuity. At the boundaries of the individual lugs, subsequently glued, and cracks appear after firing.

The aim of the invention is to improve the quality of hollow products by improving the structure of a molded beam.

FIG. 1 shows a plastic press made according to the invention, a side view with a slit; in fig. 2 shows section A-A in FIG. one; FIG. 3 is a section BB in FIG. one.

The press for plastic masses contains a supporting structure 1 (FIG. 1), on which a hopper 2 is installed for loading a formable plastic mass. The hopper 2 communicates with the pressing chamber 3. The pressing chamber 3 is bounded by the outer cylindrical surface of the forming drum 4, the surface of the arc cramp 5 rigidly mounted on the supporting structure 1, and the surfaces of two disks 6 facing the moldable plastic mass (Fig. 2).

The forming drum 4 is mounted on the drive shaft 7. The drive shaft 7 rests on the supporting structure 1 through the bearing assemblies.

The disks 6 are mounted in the bearing supports on the supporting structure 1 from the end sides of the forming drum 4 eccentric about its axis of rotation. In addition, the axes of the disks are located in the same plane with the axis of the drum 4 and form an acute angle with it.

A part of the surface 8 of each disc 6, which is in contact with a part of the end surface of the forming drum 4, is spherical.

The disks 6 are associated with a drive, which in FIG. 2 conventionally not shown.

Adjacent to the hopper 2 is an injection roller 9, the shaft 10 of which is kinematically connected with one of the disks 6.

The hollow cores 11 are mounted on arc holders 12, the middle parts of which are inserted into the annular grooves of the forming drum 4. To reduce friction in the grooves, anti-friction material rings 13 can be installed. The ends 14 and 15 of the arc holders 12 are fixed on the supporting structure 1 of the press.

To increase the ease of operation of the press by facilitating the removal of the arc holders during repairs, the holders 12 encircle the forming drum 4 on the arc (Fig. 1) with an angle of not more than 180 °,

On the supporting structure 1, an additional pressing chamber 16 is installed. Upper wall

17 is a removable knife knife, the working edge of which is adjacent to the outer surface of the forming drum 4.

Press for plastics works as follows.

The forming drum 4, the discs 6 and the pressure roller 9 are rotated. The molded plastic mass, coming from the hopper 2 into the pressing chamber 3, is attracted by the moving surfaces of the forming drum 4 and the discs 6 along the pressing chamber 3 to its exit. In this case, the plastic mass is subjected to bulk compaction due to the reduction of 5 the cross section of the chamber.

Arc holders 12, the ends of which 14 and 15 are fixed on the supporting structure 1 of the press, are fixed. Their middle parts slide along the annular grooves forming

0 of the drum 4. At the place of attachment of the holders 11 to the arc holders 12, the plastic mass passes along the chamber without forming a stagnant zone, since the total width of the holders

5 is substantially less than the tonne of the bottom surface of the forming drum 4.

The bar formed in the pressing chamber 3 enters the pre-pressing chamber 16 by means of a circuit knife 17. Here the speed of movement is equalized.

separate layers of mass and final

the formation of the structure and dimensions of the beam,

Fastening the void 11 on

arc holders 12, the middle parts of which are located in the annular grooves of the forming drum 4, allows to improve the structure of the molded bar due to the fact that in the place of attachment of the core holders to the arc holders during the operation of the press, The house is located on the surface of the forming drum. Therefore, the gradient of the speeds of movement of the moldable mass over the section of the extrusion chamber in the claimed

5 device is small. There is no loss of continuity of flow and associated structural defects that manifest themselves in the form of burnt brick cracks. Thereby, one of the most important indicators of the quality of a brick, bending strength, increases by at least 10.. 20%.

Claims (2)

Invention Formula 51. A plastic mass press containing a feed hopper, drum forming side discs, an arc-clamping mechanism and an emptying drum mounted at the outlet of the pressure chamber, characterized in that. In order to improve the quality of hollow products by improving the structure of the molded beam, the forming drum is made with annular grooves, and the press is equipped with arc holders for mounting hollow cores, while the middle part of the arc holders is located in the annular grooves of the drum, and the ends are fixed on the carrier design press. 2. A press according to claim 1, characterized in that, in order to increase the ease of operation, the arc holders enclose the forming drum on an arc with an angle of not more than 180 °, s & 9 Yu Sssss l Fig. / 11 FIG. 3 A-A I / / / -4  sf / 2 Bb