DE1020919B - - Google Patents

Description

property

of the German Pafentcszir

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

PATENT DOCUMENT 1020 REGISTRATION DAY:

NOTICE THE REGISTRATION DND ISSUE OF ' EDITORIAL:

ISSUE OF PATENT LETTERING:

kl. 80 a 6/10

INTEBNAT. KL. B 28 b JANUARY 23, 1956

DECEMBER 12, 1957 DECEMBER 24, 1958

agrees with the exposition

1 020 919 (P 1SS28 IVc / 80 a)

The invention relates to an automatic press for the production of objects from fine-grained, preferably powdery, essentially dry material with a filling device, in which the filling -the mold with the help of a displaceable above the die, bottomless filling box takes place, which in its filling position from a higher situated, bottomless, essentially immovable intermediate box is filled with the material to be pressed, which intermediate box is arranged between the end of a pouring pipe connected to a storage container and the filling box and that continuously out of the pouring pipe received press material in the FüUstelJung of the filling box releases it to the latter, a closing element being provided which, when the filling box is moved in or out of its working position, the intermediate box automatically closes or opens at the bottom.

In the known presses of this type, the press material falls directly from the storage container or from a dispenser arranged directly on the storage container through an almost vertical pouring pipe in the filling or intermediate box. If the pressing material is very fine-grained or even powdery, it will already agglomerate and compact when it hits the filling or intermediate box, so that -the density of the molding material can change significantly. However, in order to obtain uniform pressed objects within certain tolerances at a given pressing pressure, it is necessary that this starts from the filling box the molding material released from the mold always has the same density, d. that is, the entire filling always must have the same weight. In the known presses, however, this requirement is not or only imperfectly fulfilled, so that especially for pressed articles made of high quality ceramic material, e.g. B. dielectric masses or ferrites Od. Like., and which are subjected to a sintering treatment after pressing and where it is not only a question of dimensional accuracy and spatial shape, but also compliance with prescribed electrical or magnetic values that Uniformity of the filling of the mold is insufficient.

The invention overcomes these disadvantages and creates a press of the type mentioned in the opening paragraph, in which the Uniformity of the pressed objects is kept within narrow limits, by 'that the pouring tube is arranged inclined at least approximately at the natural angle of repose of the PreBmatenials.

Here, the intermediate box, which is preferably arranged directly above the filling box, always with a press material of the same static pressure, d. H. from the same height of fall, loaded, Automatic press for manufacture of objects made of fine-grained, preferably powdered material

^- ::

Patented for:

Philips Patentverwaltung G.m.b.H., Hamburg

Heinrich Schumacher, Hamburg-Langenhorn, has been named as the inventor

so that the filling box, from which the mold ultimately receives the molding material, is steady with a molding compound is filled with the same density. The one caused by the filling level of the prefabricated material in the storage container

^a 5 static pressure is not transferred directly to the material in the intermediate box in the press according to the invention, but rather through the inclined pouring pipe, the inclination of which corresponds approximately to the natural angle of repose of the pressed material catch. The amount of static pressure the Material exerts in the outlet of the pouring pipe is due to the vertical height of the outlet cross-section of the pouring pipe; however, this amount is relatively very small in comparison to the length of the bulk pipe. To the Drude over the whole width of the To keep the pouring pipe constant, according to a further development of the invention, the cross-section of the pouring pipe is rectangular or rectangular in a manner known per se. formed square.

4 »A safe sliding of the pressed material is expediently achieved by the fact that the cross-section of the pouring pipe steadily and / or gradually expanded. This loosens the material as it flows through, i.e. i.e., it finds a Relaxation of the pressure between the individual grains of material takes place.

In the known presses, in which the pressing material from a below the storage container dispenser located to the filling box over a Schütt tube is fed, although the pressure of the Ma terials in the storage container no longer on the material in the pouring pipe, but the pressed material falls through the almost vertical arrangement of the pouring pipe down a considerable distance practically free, so that when

809 693/157

Claims (17)

1 If an undesired compaction of the press material takes place. In addition, in many cases the spaces of the distributor are insufficient for the required pressing material when using a large mold, so that when the press die is replaced, the distributor must also be replaced. These disadvantages are also eliminated in the press according to the invention, since here the intermediate box continuously ge with the required amount of press material. is filled. ίο If the intermediate box widens upwards in a funnel shape and the end of the pouring pipe protrudes into this funnel, the intermediate box cannot overflow, since the press material does not flow apart, but is piled up in a pile and after reaching a certain height, the press material continues to flow out of the pouring pipe prevented. In the case of a press in which the filling device can be moved up and down to release the pressed object, the pouring tube is expediently connected pivotably both to the storage container and to the intermediate box. The connection of the pouring pipe with the outlet of the storage container can take place here through a pivot bearing having a flow opening and with the intermediate box through a pivotably mounted linkage. The invention is explained in more detail using an exemplary embodiment shown in the drawing. Fig. 1 shows a longitudinal section through a press according to the invention and Fig. 2 shows a section along the line A-B of Fig. 1 on an enlarged scale. In the plate 1 of the press table, a press die 2 with a press mold is embedded in the axial direction of the press ram, not shown. A bottomless filling box 3 is slidably arranged on the plate 1 and can be moved back and forth above the press die 2 with the aid of a hydraulically driven piston 4. The piston 4 is driven by a hydraulic system 5 connected to the plate 1. The filling box 3 runs in rails 6 which are fastened to the plate 1 and which grip around lugs 7 of the filling box 3. The filling box 3 is partially covered with a disk 9 having a large opening 8, which is connected to the filling box 3, e.g. B. is firmly connected by means of a few screws. Around the edge of the opening 8, walls 10 which are fastened to the disk 9 and carry a slide plate 11 which is provided with an outlet opening 12 rise. The walls 10 also delimit this outlet opening 12 and thus establish a tubular connection between the slide plate 11 and the filling box 3. On the slide plate 11 there is a bottomless intermediate box 13 which is provided with a funnel-shaped extension 14. In order to enable a relative movement between the slide plate 11 and the intermediate box 13, running rails IS similar to the rails 6 are attached to the slide plate and grip around small extensions 26 of the intermediate box 13 like claws. In the funnel-shaped attachment 14 of the intermediate box 13 protrudes the end of a pouring pipe 17 connected to a storage container 16 for the pressing material. By welding, while its other end is fixedly attached to a 919 bearing sleeve 19; which is rotatably arranged on a bearing pin 20 embedded in the wall of the intermediate box 13. The longitudinal axis 21 of the pouring pipe 17 is inclined relative to the horizontal in such a way that the angle α enclosed by the axis 21 and the horizontal corresponds approximately to the natural angle of repose of the pressed material. The cross section of the pouring pipe 17 is rectangular and widens steadily downwards. The functioning of the filling device described is as follows. The material to be compressed flows from the storage container 16 into the pouring pipe 17, where it slowly, and without compacting, slides down the wall and - due to the shape of the pouring pipe - is loosened. From the pouring pipe 17, the pressed material reaches the intermediate box 13, from where it flows through the outlet opening 12 of the slide plate 11 and the opening 8 of the disk 9 into the filling box 3. When the filling box 3 is provided with a sufficient amount of molding material, it is automatically moved with the aid of the kot 4 in the direction of the press die 2, where it delivers its contents to the mold. Since the molding material has retained its original consistency, the density of the material now in the mold is always the same. When the filling box 3 moves forward, the slide plate 11 connected to it also slides forward and closes the intermediate box 13 on the bottom side. The slide plate 11 is designed in the shape of a trough to catch any material that may fall by it. A sheet metal 22 is attached under the slide plate 11 for stiffening purposes. During the to-and-fro movement of the filling box 3, the pressed material flows out of the pouring pipe 17 into the intermediate box 13 until the accumulated material clogs the outlet of the pouring pipe and makes it impossible to continue flowing. After the filling box 3 has returned to the filling position shown in FIG. 1, the material accumulated in the intermediate box 13 can flow into the filling box 3 after the bottom closure of the intermediate box 13 has been released, whereupon the described process is repeated. In a press in which the plate 1 and the parts of the filling device connected to it can be moved up and down to release the pressed object, the bottom tube 17 is connected to the outlet 23 of the storage container 16 by a pivot bearing 25 having a passage opening 24. When the plate 1 goes down, it takes the filling box 3 and the slide plate 11 connected to it with it via the rails 6. With the help of the running rails 15, the intermediate box 13 and from this the pouring pipe 17 are pulled down at the same time. The supply of the press material to the intermediate box 13 is not interrupted. The pouring pipe 17 is here only pivoted downwards by such a small angle that in this position its inclination still corresponds in practice to the natural angle of repose of the pressed material. Patent claims: 1. Automatic press for making items from fine-grained, preferably powdery, essentially dry material with a filling device in which the filling the mold takes place with the help of a bottomless filling box that can be displaced above the press die, the one in its filling position from a higher located, bottomless, essentially immovable intermediate box with the. material to be pressed is filled, which intermediate box is arranged between the end of a pouring pipe connected to a storage container and the filling box and releases the pressed material continuously received from the pouring pipe in the filling position of the filling box, a closing element being provided which is provided when the filling box is moved in or out of its working position, the intermediate box automatically closes or opens on the bath side, characterized in that the pouring pipe (17) is inclined at least approximately at the natural angle of repose of the pressed material. 2. Press according to claim 1, characterized in that the intermediate box (13) is connected to the pouring pipe (17), preferably via a linkage (18) . 3. Press according to claims 1 and 2, characterized in that the intermediate box (13) widens upwardly in a funnel shape and the end of the pouring tube (17 ) protrudes into this funnel (14). 4. Press. According to claims 1 to 3, characterized in that the pouring pipe (17) has a rectangular or square cross-section. 5. Press according to claims 1 to 4, characterized in that the cross section of the pouring pipe (17) widens steadily and / or gradually downwards. 6. Press according to one of the preceding claims, in which the filling device can be moved up and down to release the pressed object, characterized in that the pouring pipe (17) is pivotably connected to both the storage container (16) and the intermediate box (13) is. 7. Press according to claim 6, characterized in that the connection • of the pouring pipe (17) with the outlet (23) of the storage container (16) through a through-flow opening (24) having pivot bearing (25) and with the intermediate box (13) a pivotably mounted rod (18) takes place. 8. Press according to claims 6 and 7, in which the closing member is designed as a slide plate fixedly connected to the filling box, characterized in that the slide plate (11) is provided with rails (15) for the intermediate box (13) , which the Zwiscrienkasten partially include claw-like so that it is carried along by the rails when the filling device moves downwards. Considered publications: German Patent No. 550231; British Patent No.; 497 251; Brandenburger, production and processing of synthetic resin molding compounds, Munich, 1934, vol. I, Die Preßtechnik, p. 48; Goetzel, Treatise on Powder Metallurgy, ■ New York, 1949, Vol. I, pp. 397 and 417. 1 sheet of drawings © 709 SM / 217 12. (809 695/157 12. 58)