SU1586856A1 - Apparatus for continuous moulding of articles from powders - Google Patents

Abstract

The invention relates to powder metallurgy, in particular, to devices for the continuous molding of articles from powders. The goal is to expand technological capabilities by ensuring the production of small diameter articles of an asymmetrical profile. The augers 4 and 5 through the gear shaft 9 from the drive is connected to the rotational motion. The powder from the hopper 8 enters the screw groove of the screw 4, is transported into the chamber, fills the through grooves of the liner and the turns of the screw 5. As it moves toward the outlet of the housing, the powder evenly compresses in the radial direction and simultaneously compresses in the axial direction. In the through slots of the liner there is a bulk compression of the powder. The internal cavity of the products is formed by forming needles 7. From the grooves of the sleeve, the blanks enter the holes of the die 3, where they are calibrated and extruded as finished products. 1 hp f-ly, 3 ill.

Description

This invention relates to powder metallurgy, in particular, devices for continuously forming articles from powders.

The purpose of the invention is the expansion of technological capabilities by ensuring the production of small-diameter articles of an asymmetrical profile,

Figure 1 shows the device, a longitudinal section; figure 2 is a cross section aa in figure 1; in FIG. 3, view B in FIG.

The device comprises a housing 1, a rack 2 on which the matrix 3 is fixed. In the housing opening there is a screw 4 with an outer thread, which has a variable depth decreasing to zero at the outlet of the housing. On the one hand, to the housing, and on the other, the screw 5 with an internal screw thread, which also has a variable depth decreasing to zero at the outlet of the housing, is rotatably attached to the rack. The screws are mounted concentrically and form a chamber in which a cylindrical sleeve 6 is placed with through longitudinal grooves. The sleeve is mounted concentric with augers and rigidly attached to the body. In the grooves of the sleeve placed attached to the body shaping needle 7; A hopper 8 is mounted on the housing. Rotational movement of the screws is transmitted from a drive (not shown) through gear shaft 9.

The device works as follows.

The augers 4 and 5 through the gear shaft 9 from the drive is connected to the rotational motion. The powder from the hopper 8 enters the screw groove of the screw 4, is transported into the chamber, fills the through slots of the sleeve 6 and the turns of the screw 5. As it progresses to the outlet from the housing, the powder is uniformly compacted from the outer and inner sides in the radial direction. Bilateral compression of the powder in the radial direction occurs due to a decrease in the depth of the screw grooves of the augers as it approaches the exit from the housing. At the same time, the powder is compressed in the axial direction, since on the side of the matrix 3, the powder is affected by the resistance force to extrusion, and the feed screws 4 and 5 develop a backpressure force in the direction of extrusion. In through the slots of the sleeve 6 is the bulk compression of the powder. When moving the powder in the direction of extrusion, its density increases and the powder takes on the appearance of the finished product. The internal cavity of the products is formed by forming needles 7. At the exit from the housing, the shape and cross-sectional area of the moldable powder billet correspond to the shape and cross-sectional area of the resulting product. From the shaping grooves of the sleeve b, the powder blanks enter the holes of the die 3, where they are calibrated and extruded in the form of finished products,

In the known device with a decrease

the outlet of the matrix, which is necessary for obtaining products of small cross section, dramatically increases the degree of reduction of the material, expressed as the ratio of the diameter of the extrusion element to the diameter of the matrix. In this connection, the pressure of the extruded material on the surface of the augers increases to such an extent that it is possible that they will jam and break the device.

Reducing the diameter of the extruding elements to reduce the degree of reduction leads to a decrease in their strength. The low strength of small-diameter screws does not allow to obtain the force required

for extrusion of undersized products, these defects are excluded in the proposed device.

A disadvantage of the known device is that with its help it is possible to obtain products of only a round profile. This is due to the fact that due to the rotation of the die and the mandrel on a known device, it is possible to obtain products of the type of rotation bodies only.

On the proposed device is possible

receiving products of various profiles. The shape and quantity of the products obtained are determined by the cross-sectional shape of the holes of the die and their number. The cavity configuration is determined by the configuration of the cross section of the forming needle.

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Claims (1)

Invention Formula 1, A device for continuous molding of products from powders, comprising a housing, a matrix, a hopper and concentrically mounted with a gap between This is an external and internal screw, so that, in order to expand technological capabilities by ensuring the production of small-diameter articles of an asymmetrical profile, it 5 is provided with a sleeve, made with through longitudinal grooves, and forming needles placed in the slots of the sleeve, while the sleeve is located in the gap between the screws and rigidly connected to the housing. 515868566 2, The apparatus according to claim 1, which is distinguished by a cutting depth decreasing to zero with the fact that the screws are made variable at the outlet of the housing. AIteJ