Multi-Jaw Forming Press Especially Suited for Details of Variable Sections

An object of the invention is a device to form materials, especially plastic materials. Advantageously this device is applicable to mass production.

Known from the GFR patent description No. 1954575 is a forming press with a minimum of three starlike arranged prismatic clamping jaws, for forming tubes. The front surfaces of the clamping jaws are directed between flat inner surfaces of a press frame and they move simultaneously to a central point of a profile orifice which is formed by the clamping jaws. The surface of the clamping jaw, which lies parallel to the axis of the profile orifice, moves on the surface of an adjoining clamping jaw, reducing the profile orifice. Identical clamping jaws, fixed inside the frame, copy with their surfaces a profile orifice corresponding with the frame's inner profile. On the frame each inner flat surface clamping jaw slides on one surface. This surface of the clamping jaw adjoins with a surface limiting profile orifice, and it lies opposite the surface, and borders an adjoining clamping jaw. In the known forming press one hydraulic drive is applied, it acts on this surface of a prismatic clamping jaw, which lies opposite the surface of clamping jaw, reducing the profile orifice.

In known forming press identically shaped prismatic clamping jaws copy the profile orifice, to form a regular figure, e.g. corresponding with the press frame inside profile. One clamping jaw drive is used, directed on the jaw surface parallel to profile orifice axis, this is an inefficient solution.

The device according to this present invention comprises movable jaws arranged around the axis thereof and lying at a common plane, perpendicular to the said axis, while each of the said jaws is provided with a guiding surface, with a profiled working surface opposite thereto, copying the final fragment of the object being formed, and two lateral surfaces. Each of the said lateral surfaces allows the movement along the lateral surface of the adjoining jaw and each of the surfaces is generated of parallel generating lines coming through the line which is the border of contact of the said adjoining profiled working surfaces. The said device further comprises a rigid system for guiding each of the said jaws along their guiding surfaces; connectors fitted in the said jaws and a driver being aligned therein, driving the said jaws through above connectors. The press comprises also a mould being adjoined to the said jaws.

The object of the invention is shown in examples of execution on drawings, on which

FIG. 1 presents in perspective view the press with displaced jaws, working surfaces of which are directed to the inside,

FIG. 2 --the same device with pushed together jaws,

FIG. 3 --the device with jaws directed outside in longitudinal section,

FIG. 4 --the same device in cross-section,

FIG. 5A --an alternative of the device presented in FIG. 3 and FIG. 4 in cross-section,

FIG. 5B is a cross-section of a portion of the device shown in FIG. 5A,

FIG. 6 --the device with mould in cross-section.

The device, according to the invention, presented in FIG. 1 and FIG. 2 is composed of three jaws 1a, 1b, 1c movably mounted on guides 2a, 2b, 2c and a driver 3 driving jaws 1a, 1b, 1c through connectors 4a, 4b, 4c. The said guides constitute a frame which is not illustrated. The driver 3 is a flat element adjacent to the jaws 1a, 1b and 1c. In the drawing, the driver 3 was shown only from one side, i.e. from the side of jaws 1a, 1b and 1c. Driver 3 is provided with a central orifice for feeding the material and with elongated orifices disposed radially to the axis of the device. Into the said elongated orifices the connectors 4a, 4b and 4c are being slidedly mounted, being embedded in jaws 1a, 1b and 1c. Connectors 4a, 4b and 4c ensure aligning the driver 3 relative to the axis of the device. While revolving, the connectors 4a, 4b and 4c move relative to the axis in the said elongated orifices. The profiled working surfaces 5a, 5b, 5c which are internally directed exert an influence on the material. Each jaw 1a, 1b, 1c moves along its guiding surface under the control of its guide 2a, 2b, 3c in such manner, that its lateral surface 6a.sub.1, 6b.sub.2, 6c.sub.3 moves on lateral surface 6b.sub.1, 6c.sub.2, 6a.sub.3 of adjoining jaw 1b, 1c, 1a. For each jaw 1a, 1b, 1c a border contact of its working surface 5a, 5b, 5c with lateral surface 6a.sub.1, or 6a .sub. 3, 6b.sub.1 or 6b.sub.2, 6c.sub.2 or 6c.sub.3 respectively latter makes this surface a guiding, on and at the same time the generating lines of the lateral surfaces are of the cooperating jaws are parallel. As presented in FIG. 1, the initial working position of the device jaws 1a, 1b, 1c are displaced. In the resulting orifice plastic material is placed. A revolution of the driver 3 relative to a rigid system of guides 2a, 2b and 2c causes the jaws 1a, 1b and 1c to move to the inside. A small movement of the driver 3 is changed by means of connectors 4a, 4b, 4c to linear movement of each jaw 1a, 1b 1c along its guiding surface. Lateral surfaces 6a.sub.1, and 6a.sub.3, 6b.sub.1 and 6b.sub.2, 6c.sub.2 and 6c.sub.3 of jaws 1a, 1b 1c slide along each other, and at the same time lateral surfaces 6a.sub.1, and 6a.sub.3, 6b.sub.1, 6b.sub.2 and 6c.sub.2, 6c.sub.3 and 6a.sub.3 of two adjoining co-operating other jaws 1a and 1b, 1b and 1c, 1c and 1a are identical and having a shape corresponding to a dividing line along a workpiece, such line being a border of contact of the adjoining profiled working surfaces 5a, 5b and 5c of the jaws 1a, 1b and 1c at their final working position. In consequence of jaws 1a, 1b and 1csimultaneous movement their profiled working surfaces 5a, 5b 5c and lateral surfaces 6a.sub.3, 6b.sub.1, 6c.sub.2 form the plastic material. In the device's final working position, presented in FIG. 2, jaws 1a, 1b, 1c are pushed together. Treated plastic material obtains a form, determined by profiled working surfaces 5a, 5b, 5c of jaws 1a, 1b, 1c. The mating lateral surfaces 6a1, 6b1, etc. between the various jaws prevents the material being extruded by the jaws from escaping between the jaws. A retraction of the jaws 1a, 1b and 1c occurs when the driver 3 turns in the opposite direction.

The driver 3 is composed of the two flat elements covering the jaws 1a , 1b and 1c, while a system of guides 2a, 2b and 2a constitutes a housing of the device. The device, presented in FIG. 3 and in FIG. 4 has jaws 7a, 7b,7c, working surfaces of which 8a, 8b, 8c are directed outside. Guides 9a, 9b, 9c, of jaws 7a, 7b, 7c are connected to each other and the device housing. Like drive 10 is an inner shaft, which through connectors 11a, 11b, 11c drives each jaw 7a, 7b, 7c. In FIGS. 5A and 5B an alternative of device from FIG. 3 and FIG. 4 is presented, in which jaws 12a, 12b, 12c are fixed on inner guides 13a, 13b, 13c and not illustrated driver (similar to the drive 3 shown in FIG. 1, but blocked from view in FIG. 5 by the jaws 1a, 1b and 1c is provided with connectors 14a, 14b and 14c embedded therein. A revolution of the guides 13a, 13b and 13c relative to the driver 3 and connectors 14a, 14b and 14c, makes the jaws 12a, 12b and 12c move. The lateral surfaces of the adjoining jaws 12a, 12b, and 12c move along each other and they move along the sides of the guides 13a, 13b and 13c via dovetail joints of the type illustrated to the right of FIG. 5

The working surfaces of the jaws 12a, 12b and 12c deform the material from the inside. It is preferable if the working surfaces of the said jaws, being externally directed, are provided with the cutting edges 15a, 15b and 15c. The device, as presented into the axial section in FIG. 6, is provided with a mould 16, being adjoined to the jaws 18a and 18n with their working surfaces directed to the inside. From the other side of the said jaws 18a, 18nit is provided with a driver 19 together with connectors 20a and 20n. The number of connectors 20a, 20n is the same as the number of jaws 18a, 18n. The jaws 18a, 18n are being placed into a rigid system of guides which are not illustrated. A portion of the material formed 17 is being fed between the jaws 18a and 18n. A revolution of the driver 19 relative to a system of guides makes the jaws 18a, 18n move to the inside in the same manner as in the device being presented in FIG. 1 and FIG. 2. Clamping of jaws 18a, 18n causes the extrusion of the material 17 into a forming mould 16. A workpiece assumes the shape of the mould 16 and of the working surfaces of jaws 18a, 18n. The solution as per this present invention enables manufacturing the details of complicated shapes and a direct extrusion of the material into a mould.

It ensures moreover cutting of the materials, clamping of the details on other elements and, if material powders or granules are initially used, it ensures obtaining shaped elements.

The device ensures a formation of bars, with cutting away the material or without cutting, in form od pyramids, balls, multi-keys or teeth and more complicatend forms, e.g. cruciform screwdrivers and semifinished cutting tools. In case of plastic material and liguids, longitudinal forming jaws perform a role of profiling adjustable diaphragm. A use of heating elements in the device according to the invention renders permissible to operate the process of forming in higher temperatures than the ambient temperature of the material. The device according to the invention is characterized by great compactness and efficiency. It can be driven manually by means of a universal press or by its own uncomplicated drives.