FI78775C - Method for joining disc-shaped pieces - Google Patents

Description

78775

The present invention relates to a method for joining plate-like bodies according to the preamble of claim 1.

The method of connecting the structural elements presented here is primarily intended as a so-called connection method. to interconnect sandwich components.

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When joining structural elements provided with a hard surface layer and e.g. a foam-like or other lower-density middle layer, practical difficulties in joining methods have been observed. If the connection takes place in 15 conventional ways, e.g. by using corner strips, screws, rivets, etc., the problem is the drilling of the structure and the local compressive strength of the structure in the vicinity of the rivet or screw. A similar structure is, of course, obtained by using glue, either alone or in combination with screws, rivets, etc., to secure the strips 20 of the corner or seam joints. It is further conceivable to brush a suitable adhesive between the element parts and to fasten them by gluing alone. The above methods use a lot of expensive manpower, and the gluing process provides an inelastic and easily tearable seam as well as an often ugly appearance as the glue exudes unevenly between the outer walls of the element. Gluing also requires a certain compression force and a certain holding time before the seam reaches a sufficient so-called purkulujuuden.

The object of the present invention is to eliminate the disadvantages of the prior art described above and to provide a completely new type of method for joining structural elements together.

This object is achieved by a method according to the invention, which is characterized by what is set forth in the characterizing part of claim 1.

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The invention provides considerable advantages. Thus - the strength of the structures increases, 5 - the total weight of the structures decreases, - other fastening parts of the structures become unnecessary, 10 - the appearance of the structures improves because finishing work becomes largely unnecessary (only removal of casting nails by cutting), - assembly time is significantly reduced several baskets can be assembled in one shift (the mold can be dismantled in less than 30 minutes after casting), - the parts of the baskets can be pre-painted before 20 assemblies, - the use of sealing is unnecessary and improves the service life of structures and - the plates can be joined together at any angle in both a rigid and flexible manner.

30 The method can be applied to the joints of both corner and straight elements. The same method can also be used to make hinges and flexible joints for structures where they have an advantage.

In the following, the invention will be considered by means of embodiments according to the accompanying drawings.

Figure 1 shows a perspective view of a car body made by the method according to the invention.

Figures 2, 3 and 6 show the application of the method according to the invention in corner joints.

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Figures 4, 5 and 11 show the application of the method according to the invention to a hinge connection.

Figures 7-10 show the application of the method according to the invention to a butt joint between two plate elements.

In the process according to the invention, the bonding agent is preferably a moldable or extrudable elastomer, in particular a polyurethane elastomer or a silicone elastomer. In the exemplary case according to Figures 10 and 3, the purpose is to cast a polyurethane elastomer to form a corner strip 8, which at the same time glues the parts 1 and 2 to be molded together without any other mechanical fastening. Prior to casting, the parts to be cast must be sandblasted or sanded and treated with a suitable primer (varnish, paint or glue) to allow the material to be cast to adhere to the site. The casting temperature of the polyurethane elastomer is +15 ... + 60 ° C, and the best results are obtained by the parts at a temperature of + 60 ° C, the surface of which is cast. 20 Casting is also possible at lower temperatures. In this case, the final strength is reached after a few days. In both cases, the pieces 1, 2 can be removed from the mold 3 »4 in less than 30 minutes, and the final strength is only required, for example, in the case of using a hinge.

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In polyurethane elastomer casting and injection molding machines, the raw materials are preheated to a temperature of +60 ... + 80 ° C, where the casting takes place. Metal parts should always be preheated. The polyurethane elastomers are dyed, if necessary, with pigments of different colors, which are mixed with the polyol. Consider Figures 1 - 3 ·

The casting of the roof strip 2 and the wall 1 as well as the corner strip of the side wall and the end wall (section A-A) takes place as follows: 35

The wall plate 1 and the roof plate 2 are positioned so that a gap of about 3 mm is left between them. Install the outer 3 and inner mold strip 4 and drill a hole 6 of about 8 mm through the outer mold strip 3 and the roof 2, thus providing 78775 as straight and short a channel as possible to the lower part of the corner connection part. When the mold strips 3 and 4 are locked in place, casting is carried out, in which the raw materials mixed by the machine flow from the nozzle 5 to the filling space between the mold strips 3 and ^ and the wall 1 and the roof plate 2. Filling is detected from the raw material flowing through the separate air hole 7. Since the polymerization of the polyurethane elastomer begins within 5 to 15 seconds of the mixing of the raw materials, the molded corner strip must be tilted so that one end of the body is higher than the other and the filling holes 6 are sufficiently close to each other. In this case, a stallion 1 liter of evening holes is not required, but the substance is injected until the substance begins to flow out of the next hole. In the vertical corner, no filling is required, but the filling takes place from the bottom up, and the used filling hole 6 is closed with a plug. Another way, in addition to tilting, is to form casting cavities of a certain size in partitions, which can be made of molded profile shaped polyurethane elastomer bodies 20 (length e.g. 5 mm), whereby casting can actually be done horizontally The casting space must not be so large that polymerization has not begun at the mouth of the filling hole. In this method, air holes are necessary. The casting pressure is not higher than the liquid pressure of the part to be cast, so there is no difficulty in supporting the moldings.

Section B-B (Fig. 3) shows the connection of the wall 1 and the base 50 10 to each other and to a steel outer corner strip 9 »which at the same time acts as a" bypass strip ". In this case, the castings take place in the recess at the top of the outer corner strip 9 and in the casting cavity formed by the inner mold strip 4 and the wall plate 1 and the base plate 10.

Exterior casting can be done directly avovaluna and the interior of the casting as shown in Figure 2. In this case, the outer corner of the strip 9 will engage the wall plate 1, a molded recess and the base plate 35 5 78 775 10 below the molding cavity. The wall and base plate adhere to each other both by means of the "baseboard" and through the end of the base plate.

Likewise, the same technique can be used to form the reu-5 of the openings, the hinge of the doors and hatches, and the manufacture of the seal.

Section C-C (Figures 4, 5 and 11) shows the edging and hinging of the door and door opening.

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The moldings 3 and 4 are mounted on the outside and inside of the wall 1 and the door hinge point. An auxiliary mold strip 13 is mounted on the inner mold strip 4, the function of which is to form the inside of the hinge, and the length of the auxiliary mold strip 13 determines the desired hinge thickness (max. 2 ... 3 mm) and the width of the auxiliary mold strip 13. . The hinge and edging can be cast in a vertical position as well as a corner joint.

Figure 6 shows a strength-correctly formed corner joint for sections A-A.

The main application for a corner joint is the joining of two sandwich * boards. The casting cavity 16 made as shown in Figures 7 and 9 (point D) 25 is suitable, for example, for joining plywood-surface elements 14, 15. The same is shown in Figures 8 and 10 (point E), which show the interconnection of the metal-surfaced sandwich elements 14, 17, 18.

30 This connection technique provides sufficient shear strength for the joint when using vertical plate (120 cm) vertical elements in the construction of the car body. Until now, this has not been known to be possible, but 35 factory-delivered glued plywood boards have been used, the price per m2 of which is almost twice that of standard boards. Likewise, the delivery time is about 5-6 weeks from the order.

In the method according to the invention, it is advantageous and necessary that the pieces to be joined are kept separate during filling of the joint, so that the elastomer to be cast, injected or extruded enters the joint in all its parts and can flow into the pores of the element material, creating sufficient contact surface division. In addition, the method presented in the present invention can advantageously be used to produce rivet-like joints which increase the strength of the joint.

For example, according to Figures 8 and 10, metallic members 19, 20 which increase the joint strength are bent, which can be e.g. perforated, whereby the liquid joint elastomer also penetrates these holes and increases the strength of the entire joint by means of its shear strength.

15 According to Figures 7 and 9, two opposite V-shaped grooves 16 are machined in the end-to-end pieces, along which the resin can be cast.

When the casting is performed for a certain distance of the mold, the mold 20 is moved forward and the new light seamlessly joins the previous one, which is not yet fully polymerized but has sufficient gel strength. The opposite part of the mold from which the elastomeric resin is inserted must, of course, have suitable air holes to provide a continuous seam 25. When using the method, the casting pressure does not have to be substantially higher than the hydrostatic pressure of the liquid to be cast, so strong fastenings of the moldings are not required.

As can be understood, the method can also be used to cast sealing strips, for example around door openings, at once pre-attached to the base body.

The method presented in this application is most preferably used for the production of series-produced space elements. Such space elements typically include car bodies, train carriages, ship cabins, site barracks, summer cottages, detached houses, etc.

Claims (7)

A method of joining corners to horns or end to end of pieces (1, 2), in particular slab-shaped building elements, according to which method - around the desired joint (8) is provided with structural constructions (3, 4), which together with the pieces (1, 2) to be joined together form hollows (16) on both sides of the joint, - into the hollows (16) such castable, extrudable or extrudable plastics, which gel after feeding, form a molded joint ( 8) with the same shape as the hollows (16) and - the mold constructions (3, 4) are removed after the joint (8) hardens, characterized in that - between the pieces (1, 2) a gap is left at the joint where the joints ( 16) with each other to provide a uniform hollow structure in which the applied plastic forms a non-abrasive joint (8) which firmly joins the pieces (1, 2). A method according to claim 1, characterized in that the sealing resin is polyurethane or polyurethane elastomer. Process according to Claim 1 or 2, characterized in that mold parts (3, 4) formed of polyolefins are used as mold material. Method according to claim 1 or 2, characterized in that such molds (3, 4) are used molds