SU859184A1 - Press for moulding articles from thermosetting materials - Google Patents

Description

The invention relates to equipment for the manufacture of articles from polymeric thermo-reactive materials, such as friction molding asbestos, and is intended for the hot forming of brake linings. A known press for forming brake linings with multi-storey multi-die molds, containing a working hydraulic cylinder, is located above the molds (1. The disadvantage of this press is the presence of multi-cavity molds, which leads to underpressures overestimate the amount per product by 10-20 g. Under conditions of mass production, such losses of asbestos reach considerable sizes.In addition, the difference between weights of asbomass in briquettes located on one floor of the press FO1 1 leads to the fact that the pressure developed by the hydraulic press distributes unevenly between them, this, in turn, leads to an increased scatter of cured pads in terms of strength, hardness, friction coefficient and wear. products from thermo-reactive materials, containing a fixed plate in the body and in the case, and a single cylinder cylinder, on the plunger of which the yoke is rigidly fixed, a movable matrix and a punch mounted between the fixed plate th and traverse. In this press the power cylinder is located in its upper part. The press has an auxiliary hydrocyliidre, which is connected with a cross-section of two columns with a transverse one, and the matrix is fixedly mounted on the latter 12. However, the presence of two cylinders in the column tt section of the column determines the slamming of the structure. In addition, these flies require increased manufacturing accuracy, and the co-operation as a whole is difficult to assemble and regulate. The pressing cylinder has an overhead arrangement, which creates the likelihood of oil entering the product. The purpose of the invention is to control the design and improve the y / o of its operation.

This goal is achieved by the fact that the press for molding articles from thermosetting materials is provided with vertical stops fixed on the ram cylinder, on which the punch is mounted, holes are made in the traverse for mounting the vertical stops, and the matrix is spring-loaded relative to the traverse.

FIG. 1 shows the press at the time of loading the material in FIG. 2 - the same during pressing; in fig. 3 is the same at the time of opening the press and removing the finished product.

The press includes fixed plate 2 and power cylinder 3 mounted on housing 1 with plunger 4. Traverse 5 is rigidly fixed to plunger 4, supporting sleeves b in which columns 7 are inserted. Matrix 8 is fixed on columns 7 Between matrix 8 and sleeves b on columns 7 Belleville springs 9 are placed. On the parts of the columns protruding from the sleeves 6 the nuts 10 are screwed.

The traverse 5 has holes 11 for vertical stops 12, which are rigidly fixed on the lid 13 of the power cylinder 3. At the stops 12, there is a punch .14, which is the bottom of the matrix 8. For fixing the punch 14, a stop 15, which cooperates with a protrusion 16 performed on the punch 14 (Fig. 1). The press works as follows. In the initial position (FIG. 1), the briquette 17 is placed in the matrix 8. In the lower cavity 18 of the power cylinder 3, fluid is supplied under high pressure, and the plunger 4 moves the yoke 5 and the punch 14 upwards to the fixed plate 2. 5, the slides on the stops 12, which serve simultaneously as guides for it, act through the cup springs 9 on the matrix 8 and also move it to the fixed plate 2. When the matrix 8 reaches the fixed plate 2, it is pressed to it with the help of cup springs 9, while poins 14 starts to affect the molding preform 17. There article (FIG. 2).

At the end of the molding, a high pressure is released from the lower cavity 18 of the power cylinder 3 and a low pressure is created in the upper cavity CE. At the same time, the plunger 4 with the coHOFv 14 and the crosshead 5 moves downwards. The punch 14 is moved to the stops 12 and remains on them, and the plunger 4 with the head plate 5 continues further movement. In this case, the yoke 5 through the sleeves 6 and the nuts 10 act on the columns 7 of the matrix 8 and rewind the last one downwards, freeing the finished product (Fig. 3).

After removing the finished product

low pressure is created in the lower cavity 18 of the power cylinder 3. Plunger 4 pushes the die 8 over the punch 14 through the yoke 5 and the spring 9. The gap between the punch 14 and the die 8 can become dirty, so moving the die upwards can also cause the movement of the punch. In this connection, after lowering the punch 14 on (the stops 12, after forming the briquette, it is advisable to fix it in this position.

In the nest formed lay the next briquette, remove the fixing. With the punch. The cycle of operation is repeated.

When rebuilding a press to mold products of other sizes, it is enough to lash the matrix and install an appropriate punch on the stops. The location of the punch on the stops makes it possible to close the press, to form, to open the press with one hydraulic cylinder located under the heated mold, which eliminates the auxiliary cylinder and columns. When the press closes, the leakage of the formed material from the die is prevented by the pressure generated by the springs. In addition, the stops passing through the holes in the traverse serve as guides for it and give rigidity to the whole system. The proposed design allows a quick restructuring of the press to form briquettes of other sizes and can be used in a unified line of the rotary type for the manufacture of disc brake pads for passenger cars, for example, Moskvich. and the Volga.

Claims (2)

1. Kozulin N.A. and others. Equipment for the production and processing of plastics. L., Goskhimizdat, 1963, p. 440. 2. US patent number 3795473, cl. 425 - 506, published. 1974 (prototype).