DE1165250B - Process for the production of deformed chipboard bodies with unequal wall thicknesses - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: B 29 j

German KL: 39 a7-5 /04

Number: 1165 250

File number: W 233381 c / 39 a7

Filing date: May 16, 1958

Opening day: March 12, 1964

The invention relates to a method for producing chip compacts with unequal Wall thickness, sharp transition and uniform specific weight of the compact, from a mixture Od of wood chips. Like. And thermosetting binders, preferably synthetic resin, by means of a mold cooperating with press punches. The mixture within the rim of the die is placed on movable rams lying next to one another, which are driven in a ratio corresponding to the desired wall thickness, poured and by the movable punch, which cover a path corresponding to the desired wall thickness in the press cycle, in cooperation with corresponding upper movable or immovable press rams to the chip compactor is pressed.

It is known that the mixture is used in the production of molded parts with unequal wall thicknesses of chips and binders according to the desired wall thickness, e.g. B. in a ratio of 5: 1, tried to pour, in view of differing wall thicknesses after the grouting to achieve reasonably uniform compression. However, this only works to a certain extent if the Wall thicknesses of the molded parts gradually become larger or smaller, with when pouring the chips a high level of manual dexterity is required in any case. In the case of a sharp or step-like However, change or transition in the thickness is a desired one according to methods known to date Wall thickness corresponding pouring not possible, so that after pressing the glued Chips at the transition from one to the other thickness of the compact, i.e. at the fold, an overcompaction or a specific weight that is too high arises, while in particular the corner of the thicker one Part or its upper region in the transition area from the smaller to the larger wall thickness Has under-compression and thus too low a specific weight. The strength in this As a result, the area of the chip pressed part is usually not sufficient. With sharp transitions from small ones Too great wall thickness is a corresponding pouring in the press tool, which only consists of one, the Form-giving solid upper and lower part is impossible, since the glued chips are only in one let it pour at a certain angle. These adverse consequences occur both in the manufacture of Pre-pressings without the action of heat with a cold press, as well as when pressing molded parts under the action of heat with a hot press.

Method of making deformed
Chip compactors with unequal wall thicknesses

Applicant:

Veneer and plywood factory JF Werz jr. KG, Werzalit Preßholzwerk Oberstenfeld,
Oberstenfeld (Württ.)

Named as inventor:

Edmund Munk, Oberstenfeld (Württ.)

Another major disadvantage is that when it is uneven Compression or, if the specific weight is uneven, direct compression of the Compression molded with synthetic resin-impregnated papers, e.g. B. melamine papers, causes great difficulties, there is sufficient pressure for the connection of the body with these papers either There is no connection and hardening of the paper, or at the points where a Over-compaction occurs, this is marked on the surface.

In order to counter the disadvantages outlined above, process methods have been developed

according to which a bed roughly adapted to the shape of the desired part in several pouring stages is achieved, wherein the bottom of the part is pressed in a first pressing pass and an inserted through Boundary cores limited second bed pressed together with the ground in a second pressing cycle the delimiting core inserted in each case before the final pressing out of the press or the press passage must be removed. However, as already mentioned, these processes require several pouring and press passages with the aid of the delimitation cores not belonging to the press tool.

In the event that a molded part is pressed according to this method in a hot press, however a homogeneous connection between the two

Compression-related molding compounds are no longer possible because the binding agent of the first compact is already present is cured after the first pressing stage. The shavings that have been poured out are retained after they have been removed of the inserted delimitation core

Schüttform not with and give way when pressing to the side, so that also an even compression over the entire cross-section and fixed,

409 538/484

sharp edges and transitions from one wall to the other cannot be achieved.

The invention consists in that a mixture of wood chips or the like and thermosetting binders within the border of the die to that of the respective shape of the different wall thickness parts pressure surfaces adapted to the compression molding, e.g. in a ratio of 5: 1 to the finished molding, be piled up. In the number of these wall thickness parts provided, next to one another, if necessary concentrically vertically movable ram with a corresponding unequal height then with corresponding upper movable or immovable press punches, the different, have compression strokes corresponding to the desired wall thicknesses, pressed together. The glued Chips are applied to the individual movable and immovable press rams of the lower part of the tool, corresponding to the desired wall thickness - e.g. in a ratio of 5: 1, based on a neutral one Line - are open, in exact proportion to the wall thicknesses required after the grouting poured by simply pouring it in. The upper part of the tool is also in the desired ratio - e.g. B. 5: 1, based on a neutral line - open. The filled, glued chips are then pressed from two or more sides, the ram simultaneously or successively be driven up to the limit that gives the shape. The number of rams depends according to the number of sharp transitions from small to large wall thicknesses and vice versa. With the Process is achieved that the mold can be loaded very easily by filling and the parts can be compacted evenly in one pressing cycle, resulting in a uniform strength of the Part also guaranteed at the transitions and edges. A compound according to the invention Process produced molded body with synthetic resin-impregnated papers, z. B. melamine papers, is possible without difficulties due to the even compression of the body.

To illustrate the process according to the invention, the drawing shows a schematic representation of the process principles. According to this illustration, two lower rams 1 and 2 and an upper ram 3, which are delimited and guided by a rigid jacket 4, are used to practice the method. The rams are movable and can be operated together or independently of one another. The rams 1, 2 and 3 are - based on an assumed neutral line - open in a ratio of 5: 1. The entire space between the movable and rigid parts of the tool (filling space 8 a) is filled with loose, glued chips from above or from the side before pressing. In the press cycle, the punch 1 covers the path 6 α minus 7 a, the punch 2 the path 6 b minus 7 b and the punch 3 the path 6 c minus Ic , so that the volume of the glued chips of 6 a Ία, is compressed from 66 to Ib and from 6c to Ic . As a result, the glued chips poured loosely in the filling space 8 a are pressed together to form the molded body 8 b.

Claims (1)

Claim: Process for the production of molded articles from a poorly flowing but pourable one Mixture of wood chips or the like and thermosetting binders, preferably synthetic resin, with uneven wall thicknesses, sharp transition and uniform specific weight by means of a press mold cooperating with press rams, characterized in that the mixture within the border of the Press mold to that of the respective shape of the different wall thickness parts of the molded body adapted pressure areas of provided in the number of these parts, side by side, if necessary applied concentrically vertically movable press rams of unequal height and from these in cooperation with corresponding upper movable or immovable press punches with different, the desired Wall thicknesses with the same compression ratio corresponding compression strokes is compressed. Considered publications:
German Patent No. 880 482;
Swiss patent specification No. 318 546. 1 sheet of drawings 409 538/484 3.64 © Bundesdruckerei Berlin