DE2821133B1 - Method of joining the ends of mitered hollow profiles - Google Patents

Description

The invention relates to a method for connecting the ends of mitered hollow profiles Made of thermoplastic material, in particular for the manufacture of window and door frames, in which the Over the entire length or in the corner area reinforced plastic hollow profiles on the Miter surfaces are permanently connected to one another using pressure and heat.

Methods for joining the ends of mitered plastic hollow profiles are well known. This known method includes, for example, miter corner welding, as described in DE-OS 2017 461. There, the end faces of the profiles to be welded in the miter corner area are brought to welding temperature by heating elements and then connected to one another by the action of compressive forces.
In DE-PS 16 59 436 a corner connection in the miter cut area of plastic hollow profile frames is described, in which the hollow profile frames are provided with stiffening profiles up to the corner, the stiffening profiles in turn having pegged plastic inserts reaching into the corner. These

ίο Plastic inserts are used together with the plastic hollow profile frame brought to welding temperature and then welded.

In this way, continuous reinforcement via the stiffening profiles is also achieved in the miter cut area.

From DE-GM 73 38 699 an angle connection for plastic frames is known, which is one of the many Describes the possibilities of locking connections in the miter corner area. In these cases there is a weld not mandatory. Such composite window frames can only be used to a limited extent, however. because the miter cuts and other openings are maintained in the visible area.

Finally, from DE-PS 17 79 361 a method for welding profile ends is known in which Metal hollow profiles provided with a plastic cover are connected to one another in the mitred corners will. With this method, the plastic covers in the miter corner area are so far above the Edges of the covered metal hollow profiles that enough plastic material for welding the Covers to each other is in place. In addition, with this method, the clear opening of the closed connecting metal profiles in the miter cut area also protruding plastic inserts introduced, which are softened together with the protruding plastic cover and finally welded.

A complex connection technology is common to all of these known corner connection methods. the Connections must be carried out in several procedural steps, with the individual deposits and Reinforcement elements each have to be held firmly. In addition, the welding mirror process is at the heating of the mitred corners is cumbersome and time-consuming. The mechanical connections in the Corner areas have the disadvantage that in addition to a considerable effort in the field of vision or openings Column remain.

The invention is based on the object

so method of making a corner joint from with To create plastic hollow profiles provided with metal reinforcements, in which the plastic hollow profiles only are firmly connected to each other in the visible corner area, while those outside the visible area lying sub-areas including the depressions for the fitting of the connection can be excluded.

This object is achieved according to the invention in that in the corner area of the corner reinforcement a circumferential Spacer element is arranged, the outer contour of which is at least partially smaller than the outer contour of the Hollow profiles, and at least partially attached to the tabs made of thermoplastic material that the Project beyond the outer contour of the hollow profiles and have cavities between them and the spacer element, that the hollow profiles are applied to the spacer element and then by applying pressure and Ultrasonic energy on the protruding hollow profiles

ORIGINAL INSPECTED

Parts of the tabs the thermoplastic material is displaced into the cavities and so the hollow profiles be connected to each other.

The subclaims relate to advantageous features of a spacer element for implementing the invention Procedure.

The method according to the invention for the corner connection of plastic hollow profiles with corner reinforcements has the advantage that on the one hand solid connections are created in the corners, while on the other hand with the fixed connection of the plastic cover only the visible surfaces are expensive Welding processes must be supplied. This means a significant simplification of the production and thus represents a particular advantage in the invention.

The welding according to the invention does not take place in the welding mirror process by heating the end faces to be welded together, but after the miter cut surfaces have been created Plastic hollow profiles carried out on the spacer element by ultrasonic welding. When inserting the ultrasonic welding are the thin retaining bars that hold the curtain plastic strips Hold it on the surrounding base part, melt it together with the plastic strips in front of it and serve to fill the cavities between the miter cut surfaces of the plastic hollow profiles and the assigned outer areas of the circumferential ring.

The ultrasonic welding method used in the method according to the invention is not very expensive and creates a completely uniform corner connection in the visible areas of the plastic hollow profiles. A seamless connection in these areas is achieved if the plastic material of the spacer element is the same material as the material of the plastic hollow profiles.

It is also to be regarded as an advantage that the cavities between the outer regions of the spacer element and the created miter cut surfaces of the plastic hollow profiles a complete leveling the protruding wall parts of the spacer element over the outer surfaces of the plastic hollow profiles enable. In this way it is prevented that weld seams after welding - as is the case with Mirror welding process is required - must be reworked afterwards. The inventive The one-time welding process creates a connection between the outer surfaces the plastic hollow profiles, which no longer require rework.

Finally, another advantage is the fact that the welded connection of the outer areas is fundamental only takes place in the visible area of the plastic hollow profiles. The design of the Spacer element this special feature must be taken into account. The welded connection in the field of vision creates a seamless transition and thus a waterproof connection of the outer areas of the plastic hollow profile. In the areas in which the spacer element is not fitted with any plastic strips are, will be a waterproof seal and special consideration for the appearance of the finished corner connection not required. In these areas, the spacer is butt between the two miter ends of the plastic hollow profiles. If necessary, a Welding is carried out by ultrasound, but then a concave indentation of the profile on these Places in the welding area takes place

The invention is illustrated by the drawing ki exemplary embodiments. It shows

F i g. 1 - An isometric view of the joining process

F i g. 2 - An embodiment of the spacer element

Fig. 3 - The spacer element according to Fig. 2 in cross-section

The F i g. 1 is a miter corner reinforcement 1 corresponding in cross section to the clear width of the plastic hollow profiles 2, 3 partially in the plastic hollow profiles 2, 3 shown pushed in. The spacer element 4 is in the corner of the mitred corner reinforcement 1 arranged. To carry out the method according to the invention, the plastic hollow profiles 2, 3 are so pushed far onto the miter corner reinforcement 1 until the miter cut surfaces 21,31 at the associated Rest outside areas of the spacer element 4.

The plastic hollow profiles 2, 3 can be provided with longitudinally continuous metal reinforcements 22, 32 be, the metal reinforcements 22, 32 either inserted subsequently into the plastic hollow profiles 2, 3 or be encapsulated with the plastic material in a one-piece manufacturing process can. It is considered useful if the metal reinforcements 22, 32 in largely accurate Contours are held to which the miter corner reinforcement 1 in their outer contours in such a way it is adapted that a fitting insertion of the miter corner reinforcement 1 into the metal reinforcements 22, 32 formed hollow chambers 23, 33 is guaranteed.

F i g. 2 shows the spacer element 4 with the base part 42, which via the thin retaining webs 43 the Plastic strips 41 are hung.

From the illustration it can be seen that the plastic strips 41 are only three partial areas of the outer contour of the Cover spacer element 4. These covered sub-areas are arbitrarily selected and can be used in the If necessary, be arranged at other points of the spacer element 4. You can also use all outdoor areas of the spacer element 4, so that a full-surface welding of the miter cut surfaces over the circumference 21,31 of the plastic hollow profiles 2, 3 can take place.

In FIG. 3, from the cross section of the spacer element 4, which is indicated by the line AA in FIG. 2 has taken place, the advantageous cross-sectional shape of the spacer element 4 for the subsequent ultrasonic welding can be seen. In the upper area of the illustration, the section shows the curtain-type plastic strip 41, which is connected to the circumferential base part 44 via the thin retaining web 43. 2 that the circumferential base part 42 can be kept narrower at the points at which the curtain-type plastic strips 41 are arranged via the thin retaining webs 43 than at the points at which the curtain-type plastic bars 41 are omitted.

The drawing shows that between the abutted miter cut surfaces 21,31 of the plastic hollow profiles 2, 3 and the assigned outer areas of the spacer element 4, the cavities 5, 6 remain, which in the subsequent process of ultrasonic welding by leveling the protruding

Parts of the curtain-type plastic strip 41 are filled will.

The shapes of the plastic hollow profiles 2, 3 shown in the illustration are merely exemplary and can be replaced by any other profile shape.

It is essential that the miter corner reinforcement 1 must change its cross-sectional shape accordingly in these cases. The spacer element 4 is also not limited to the embodiment shown. Its cross-sectional dimensions and its circumferential profile can be adapted to the changed cross-sectional shapes of the plastic hollow profiles 2, 3 and the requirements.

Not shown in the drawing are the embodiments of the spacer element as shown in FIG Claims 3-6 are laid down. Thus, according to claim 3, on the bearing surfaces 45 of the base part 42 Not shown latching elements be formed, which in also not shown latching recesses in the Can intervene in the area of the miter corner reinforcement 1. According to claim 4 can also be in the area of Miter corner reinforcement 1 a circumferential groove into which the base part 42 of the spacer element 4 can be determined. Another possibility is that the miter corner reinforcement 1 itself consists of plastic and in the miter corner area, the spacer element 4 is integrally attached to the miter corner reinforcement 1 is molded. This can be done, for example, in the manufacture of the miter corner reinforcement 1 in Injection molding process take place.

Finally, there is also the possibility according to claim 6, the base part 42 of the spacer element 4 to subdivide at least once in cross section and latching means on the dividing surfaces for mutual Arrange locking connection. In this context, for example, a so-called tongue and groove connection can be used be used.

For this purpose 2 sheets of drawings

Claims (6)

Patent claims: 1. Method of joining the ends of mitered thermoplastic hollow profiles Plastic, especially for the manufacture of window or door frames, in which the full length or in the corner area reinforced plastic hollow profiles on the miter surfaces are inextricably connected to one another using pressure and heat, characterized in that in the corner area the corner reinforcement a circumferential spacer element (4) is arranged, the outer contour of which is at least partially smaller than the outer contour of the hollow profiles, and at least partially on that Lugs (41) made of thermoplastic material are attached, which form the outer contour of the hollow profiles protrude and have cavities between them and the spacer element (4) that the hollow profiles be applied to the spacer element (4) and then by applying pressure and ultrasonic energy on the parts of the tabs protruding from the hollow profiles, the thermoplastic material in the Cavities is displaced and so the hollow profiles are connected to one another. 2. Connecting element for performing the method according to claim 1, characterized by a circumferential spacer element (4) that can be placed on the miter corner reinforcement (1) and to which thin holding webs (43) curtain-type plastic strips (41) are integrally formed. 3. Connecting element according to claim 2, characterized in that on associated bearing surfaces of the spacer element (4) locking elements are formed, which in locking recesses in the area the miter corner reinforcement (1), the spacer element (4) can intervene securely on this. 4. Connecting element according to claim 2 and 3, characterized in that the spacer element (4) can be fixed in a circumferential groove arranged in the area of the miter corner reinforcement (1). 5. Connecting element according to claim 2, characterized in that it is made of plastic Miter corner reinforcement (1) is integrally formed on this. 6. Connecting element according to claims 2-4, characterized in that the spacer element (4) is divided at least once in cross section and locking means on the dividing surfaces to the retaining has mutual locking.