FI64435B - BINDNINGSBULT FOER BETONGBRAEDFODRING - Google Patents

Description

64435 ί

The present invention relates to a bonding bolt according to the preamble of claim 1. Such a bolt 5 is used to bond concrete slabs against the casting pressure caused by the concrete.

It is already known, for example, to use round steel, which is cut from the inside of the concrete by puncturing a hole of about 2 to 5 cm in the concrete, which is then placed in place. However, this method is expensive, and in addition, the patch residue degrades the finished concrete surface.

It is also known to use tie bolts made entirely of stainless steel, which are cut from the surface after the boarding has been dismantled.

15 However, such fastening bolts are very expensive due to the high price of the raw material.

It is still known to use a protective tube around the actual tying bolt, whereby the bolt is pulled out when the boarding is dismantled. Although this method is inexpensive, it is not suitable for use if the concrete structure is required to be waterproof or have good sound insulation properties.

The object of the present invention is to eliminate the drawbacks 25 of the prior art and to provide a completely new and more practical concrete board fixing bolt.

The invention is based on the idea that the stainless material is used only on the part of the bonding bolt which is susceptible to corrosion in the final structure.

More specifically, the fastening bolt according to the invention is characterized by what is set forth in the characterizing part of claim 1.

The invention provides considerable advantages.

Thus, the fastening bolt according to the invention is inexpensive. It is faster to install and the finished structure looks better than previous methods. In addition, the flash welding used to join the different parts of the tie bolts enables both favorable manufacturing and operating conditions, since the part to be cut from the tie bolt can be reused.

The invention will now be examined in more detail with reference to the drawing 10 according to the appended appendix.

Figure 1 shows a side view of one of the fastening bolts according to the invention.

Fig. 2 shows a sectional view of the bolt according to Fig. 1 installed in place.

Figure 3 shows a sectional view of a second bolt according to the invention mounted in place.

Figure 4 shows a sectional view of a third bolt according to the invention installed in place.

Figure 5 shows a fourth bolt 20 according to the invention in place.

The bonding bolt 1-3 according to Figures 1 and 2 is intended to extend through the concrete layer 13 and the limiting paneling 11, 12 so that its ends 1 protrude outside the paneling 11, 12 25 for mounting the fastening and / or tightening members 4, 5. The bolt 1-3 comprises e.g. a brush steel inner part 3> stainless steel intermediate parts 2 axially connected to both ends of this inner part 3 and outer parts 1 connected to the outer end of these intermediate parts 30. The outer parts 1 are made of conventional steel, e.g. smooth or threaded round steel. It is also possible that the intermediate part 2 and the outer part 1 are, for example, the same piece made of stainless steel.

The intermediate part 2 is dimensioned so that its outer end 1, 3 64435 with the fixing bolts 1-3 in place extends approximately to the surface of the concrete layer 13 to be cast (Figures 4 and 5). According to Figures 2 and 3, it may also extend somewhat beyond this surface 5. The length of the intermediate part 2 made of stainless steel depends on the case, being in the range of 3 ··· 15 cm, which is most suitable.

Parts 1-3 are attached to each other in the so-called by flash welding. It causes a welding current to pass through the end-to-end bodies 1-3, which, when the bodies are occasionally brought into contact with each other, form an arc between them.

The arcs heat the ends of the pieces 1-3 to the welding temperature, and welding is accomplished by pressing the ends of the pieces together. Labeling begins when the surfaces are heated to near the melting point of the substance. The stamping voltage is always selected according to the pieces 3 ... 1 ^ V. Current-. . 2 months in flash welding may rise to a value of approx. 150 A / mm.

20 Compression 1. Punching is usually done using small 2 forces, approx. 10 ... 40 N / mm. The compressive force and speed are chosen so that oxidations and impurities on the surfaces are removed from the welding slit.

In the case where the intermediate part 2 and the outer part l are the same piece, this piece 2, 1 is connected to the end of the inner part 3 by flash welding.

The removable parts 1 can thus be made of better steel, if necessary, since they can be reused 30.

Within the scope of the invention, various modifications can be considered, depending on the intended use and working method. Thus, when the outer part 1 is made of smooth steel, the tightening can be handled by means of a mold lock 4 (Figs.> 2, 4 and 5).

35 If the outer part 1 is equipped with threads 8, tighten. » f 4 64435 can be operated by means of a threaded bolt 7 and a base plate 6 (Fig. 3). It is also possible to use a threaded mold lock, in which case the outer part is made of threaded brush steel.

Fig. 4 shows a solution according to which the outer end of the intermediate part 2 has a flange structure 9, which prevents the boarding 11, 12 from penetrating.

In the solution according to Figure 5, in addition to the flange structures 9, the inner end of the intermediate parts 2 has a second flange structure 10 10. The flange structures make the structure waterproof.

Finally, it should be mentioned that after dismantling the boarding 11, 12, the external parts of the concrete 13 are removed, either by striking the bolt 1-3 or cutting it with a racket.

Claims (10)

1. Binding bolt (1-3) of rigid concrete board liner (11, 12), said bolt intended to extend 3 through a concrete layer (13) and the board liner (11, 12) defining it, so that at least its one end (1) protrudes beyond the board liner (11, 12) e.g. in and for mounting of fastening and / or clamping means (4-7) in place, characterized in that the bolt (1-3) comprises an inner part (3) of a conventional frame, e.g. core frame, at least one stainless steel shaft middle member (2) secured to the inner part (3) and at least one outer part (1) axially attached to the outer end of the middle part (2). Binding bolt according to claim 1, characterized in that the outer part (1) is made of conventional frame. 3. Binding bolt according to claim 1, characterized in that the intermediate part (2) and the outer part (1) are in one piece off of stainless steel. Bonding bolt according to claim 1, characterized in that the intermediate part (2) is dimensioned so that its outer end when the bonding bolt (1-3) is mounted in its place extends at least to the closest to the surface of the concrete layer to be cast. Bonding bolt according to claim 1, characterized in that the intermediate part (2) is dimensioned so that its outer end when the bonding bolt is mounted in place extends at least slightly beyond the surface of the concrete layer to be cast. Binding bolt according to claim 1, characterized in that the axial length of the intermediate part (2) is 3 ... 15. , v * »