EP1277892B1 - Sleeve connection for concrete reinforcement rods - Google Patents

Abstract

The sleeve connection for a concrete reinforcement rod has a sleeve attached to the opposing ends of each rod. One sleeve forms a male connector (1) with an externally threaded pin (5). The other sleeve forma female connector (10) with an internally threaded bore. One of the sleeves has a deformable section (15) which is deformed when the threaded connection is made to provide an axial pre-load on the joint. The preload prevents rotation of the joint.

Description

The present invention relates to a socket connection for reinforcing steel bars, wherein the reinforcing steel bars at their ends to be joined in each case with the one End of a male or female female part are connectable and the male-female part has a pin with external thread at its other end, while the female socket part at its other end a bore with corresponding Internal thread has, so that both sleeve parts together are screwed, wherein the male or female female part at least one Projection, the deformed by screwing the two sleeve parts so is that of a deformation resisting resistance of the projection an axial biasing force between the threads of the two sleeve parts causes.

In the course of an optimized construction process or from static requirements, it is often necessary to connect axially successive reinforcing steel bars together. In addition to an overlapping of the reinforcing steel rods, in which the end sections of Reinforcing steel bars overlap and these overlapping areas welded together It is also known, the reinforcing steel bars with the help of the above To connect screw sleeves.

In this case, the male and female female parts either by pressing connected to the corresponding bar end with the reinforcing steel bar or through a screw connection, in which the rod end first a special thread is applied, then screwed onto the socket part. The connection the two sleeve parts themselves are then done by screwing the cylindrical External thread of the male socket part with the cylindrical internal thread of the female socket part.

In order to obtain a building inspection approval of such a socket connection, It is necessary to avoid the formation of cracks in the concrete joints between the rebars in their slippage behavior, the means that the forces acting in the concrete should as far as possible not be axially offset effect between the bars. Permitted is a total offset of all involved Butt joints, ie the joint between the first reinforcing steel rod and the female socket part, between the female socket part and the male socket part and between the male socket part and the second concrete steel rod of not more than total 0.1 mm.

To the slip between the male-female part and the female-female part so far As is possible, it is known in the art to use male / female threads with a defined force, in particular with a torque wrench to create an axial biasing force that seeks to slip counteracts the thread due to external stress. However, stand on construction sites generally no torque wrenches available; besides, that is Achieving a defined preload force even when using a torque wrench often not guaranteed.

It is therefore by EP-A-0 816 584 a sleeve joint having the features the preamble of claim 1 become known, in which a deformable Projection is provided, which deforms when screwing the two sleeve parts is that an axial biasing force between the threads of the two Cuff parts are created. The projection is arranged at the end of the reinforcing steel bar, which is pressed with the female socket part. This projection is when screwing deformed the male-female part of the front end side. The deformation thus takes place inside the female socket part. To guarantee a sufficient depth of engagement and thus deformation is at the rear At the end of the male-female part a stop attached, which when screwing in plant with the female socket part.

Based on this prior art, the present invention has the object on, the known socket joint for reinforcing bars continues to improve, with the maximum offset limit even without a torque wrench to be complied with.

This object is achieved in that the deformable projection is arranged on an end face of a sleeve part, which after the Screwing abuts on a corresponding end face of the other sleeve part. The end face must be directly or indirectly with the respective socket part be connected. For the arrangement and training of such faces on the Female or male socket part are several possibilities conceivable. So can the End faces the respective sleeve part, for example, radially surrounded as a ring, so that overall results in a flange-like design or it can already on existing end faces are used.

Expediently, the deformable projection projects axially in the direction of the other Sleeve part in front. As a result, the main component of the force resulting from the Resistance of the projection against its deformation results in the axial direction. But it is also conceivable that the projection radially, obliquely or in the circumferential direction projects.

In this context, it is particularly advantageous if the end face, on which the deformable projection is provided at the end of the male or Female-sleeve part is arranged. If the deformable projection on the Male-sleeve part is arranged, the end face can by a radial circular area be formed at the transition between threaded pin and male-female part. If the deformable projection is provided on the female-female part, the End face through the end, the threaded bore enclosing radial annular surface be formed of the female socket part.

A very important development of the principle according to the invention is form the deformable projection such that by screwing the two sleeve parts a defined biasing force and thus a predetermined Slip restriction is generated. In the process, the determining parameters become the projection, such as its material, its shape, size and position and the Extent of salience and the like on the one hand and the parameters of On the other hand sleeve parts (in particular their thread dimensions) to each other agreed that a desired slip restriction between the Both sleeve parts is achieved.

In this context, it is favorable if the predetermined slip restriction after screwing the two sleeve parts to the seamless system the two faces occurs. This is a visual control alone certain axial preload adjusted by a defined deformation of the Projection is generated.

As for the material of the deformable projection, so elastic Material, especially rubber can be used. Due to the elasticity of a such projection, is also a multiple screw with subsequent Loosen the sleeve parts possible without changing the size of the projection caused axial biasing force adversely changes.

The deformable projection may expediently be partially into a groove be inserted ring. The groove can u.a. in the end-side Ring surface of the female-sleeve part may be arranged, which surrounds the threaded bore.

According to a second, particularly favorable alternative of the invention is the deformable Projection as preferably integrally connected to its sleeve part Material edge, in particular milling edge formed, which expediently obliquely forward towards the other sleeve part can protrude and as freestanding ring is formed. When screwing the two sleeve parts is then this ring bent up to a stop. The deformation goes here expedient beyond the elastic range in the plastic area.

It is particularly advantageous in this context if the material edge after deformation into a at its sleeve part, in particular at the end-side End face provided groove can be pressed into it, so that both sleeve parts almost seamlessly abut each other. The to be overcome during the deformation Resistance of the material edge causes the axial preload force, the Thread of the sleeve parts limited in their slip behavior.

In this case, the deformable projection on the male or female socket part in Essentially be directed radially outward, so that when screwing the Cuff parts axially kinked away. The occurring bending resistance against the Deformation of the protrusion then acts in a similar manner to the above Embodiments explain the axial preload between the threads of the two sleeve parts.

In special applications, a socket connection is also desirable if the reinforcing steel bars can not be twisted, so For example, are already embedded in concrete or due to their relocation more or are less fixed. In such cases, it is not known, the sleeve parts directly screw together, but indirectly, namely with interposition of rotatable bridging parts. So here, too, the desired preload force can be generated, it is within the scope of the invention, the previously described deformable projection not or not only on the sleeve parts to arrange, but optionally on the bridging parts. Decisive in this is that at each screw connection the male or female bypass part by at least one deformable projection of the desired tension is subjected.

Further advantageous embodiments and features of the invention will become apparent from the following description of exemplary embodiments and from the Drawings for these embodiments.

Figur 1

jeweils ein Male- und ein Female-Muffenteil im Längsschnitt entlang der Mittelebene mit deformierbarem Vorsprung am Female-Muffenteil;

Figur 2

den Endabschnitt des Female-Muffenteils im Längsschitt;

Figur 3 (a)

einen Längsschnitt einer weiteren Ausführungsform eines Female-Muffenteils mit deformierbarem Vorsprung;

Figur 3 (b)

das Muffenteil gemäß Figur 3 (a) nach dem Verschrauben;

Figur 4 (a)

eine andere Alternative eines Male-Muffenteils mit deformierbarem Vorsprung im Längsschnitt;

Figur 4 (b)

den Vorsprung gemäß Figur 4 (a) in vergrößerter Darstellung;

Figur 4 (c)

den Vorsprung gemäß Figur 4 (b) nach seiner Deformation;

Figur 5

eine Muffenverbindung mit Überbrückungsteilen.

Showing:

FIG. 1

in each case one male and one female female part in longitudinal section along the median plane with a deformable projection on the female female part;

FIG. 2

the end portion of the female-female part in the longitudinal section;

FIG. 3 (a)

a longitudinal section of another embodiment of a female-female part with deformable projection;

FIG. 3 (b)

the sleeve part according to Figure 3 (a) after screwing;

FIG. 4 (a)

another alternative of a male-female part with deformable projection in longitudinal section;

FIG. 4 (b)

the projection of Figure 4 (a) in an enlarged view;

FIG. 4 (c)

the projection according to Figure 4 (b) after its deformation;

FIG. 5

a socket connection with bridging parts.

FIG. 1 shows a male socket part 1 of a socket connection in the left-hand illustration for not shown here reinforcing steel bars, with its free end 2 on a pressed to be joined reinforcing steel bar or screwed by a thread becomes. For this purpose, the free end 2 a to the outer diameter of the Reinforcing steel rod adapted concentric bore 3.

At a radial end face 4 of the other free end of the male-female part 1 a cylindrical pin 5 is formed, which has an external thread 6. With This external thread 6, the sleeve part 1 in a bore 11 in the Right-hand drawing shown Female-female part 10 with a in this bore 11 arranged internal thread 12 are screwed. The bore 11 closes terminal with a radial annular surface 13 from.

It is essential that in this terminal annular surface 13, as shown in Figure 2, an annular groove 14 is recessed and that in this groove as an elastic deformable projection serving rubber ring 15 is inserted, the axially something protrudes from the annular groove 14. When screwing the two sleeve parts 1, 11 each other this projection with a corresponding screwing depth of the pin 5 pressed against the radial end face 4 of the male-female part 1.

By further screwing the rubber ring 15 is then pressed until the radial annular surface 13 of the female-female part and the radial annular surface 4 of the Male-sleeve part lie almost seamlessly together. It is from the rubber ring 15 causes an axial biasing force, the slip tendency of the thread counteracts the two sleeve parts. The determining parameters for the tension, such as hardness, shape and size of the projection, its projection and the like on the one hand and the two sleeve parts on the other hand are so on each other tuned that a defined slip restriction between the two sleeve parts is achieved.

It is of course also within the scope of the invention, a rubber ring on the radial Provide end face 4 of the male-female part 1 and for the rubber ring 15 at omit the female socket part 10. Furthermore, it is conceivable both one or more deformable male and female female parts Provide projections.

In FIGS. 3 (a), 3 (b), a particularly advantageous embodiment of the present invention is shown Invention shown.

FIG. 3 (a) shows a female socket part 20 with a bore 21 with an internal thread, in which, unlike the female-female part 10 of Figure 1, no in one Ring groove inserted rubber ring is provided, but an obliquely forward in the direction of an unillustrated male-female part facing milling edge 22, the extending from a bore 21 enclosing, end-side radial end face 23. The milling edge 22 has a material thickness in the millimeter range and forms an approximately axially projecting, circumferential in the circumferential direction ring.

Radially inside the milling edge 22 to the bore 21 or its conical Connecting outlet, while radially outside a concentrically arranged Ring groove 25 connects.

By screwing the two sleeve parts this milling edge 22 upon impact elastic and preferably on a corresponding end face of the male-female part plastically deformed such that it provided in the end face 23 in the Ring groove 25 dips, as Figure 3 (b) shows. This makes it possible for that the radial end face 23 after the screw connection of the two sleeve parts almost jointlessly applied to the corresponding end face of the male-female part.

In this embodiment, the deformation resistance of the milling edge 22 generates the axial preload force between the two sleeve parts.

Finally, in Figure 4 (a) - (c), in contrast to the embodiments described above a deformable protrusion is disposed on a male-female part.

The male-female part 30 shown in FIG. 4 (a) has the male-female part 1 from Figure 1 via a bore 31 for screwing or pressing on a Reinforcing steel rod and one formed on a radial end face 32 Spigot 33 with external thread 34 for screwing it into a corresponding Bore of a female-female part, not shown here.

It is essential that in the transition region 35 between the pin 33 and the end face 32 - better seen in the enlarged detail Figure 4 (b) - a deformable projection extending substantially radially outward 36 is formed directly, preferably still slightly forward to Thread 34 extends.

This projection 36 can be easily generated by unilateral radial recess 37 be, with the resulting annular groove at the same time the receiving space for the forming later deformation of the projection 36. At the opposite of the puncture Side of the projection 36 may advantageously made a groove 38 so that the projection protrudes obliquely forward.

When screwing the male-female part 30 with a corresponding female-female part, the projection 36 is then by hitting the end-side end face the female socket portion is bent axially rearwardly as shown in Figure 4 (c), wherein the projection in the transition region 35 also after screwing further connected to the sleeve part. He is finally at the back End face 32 and thus visually clearly indicates the end of the screwing. An unnecessarily strong or excessive tightening of the screw is thus avoided; At the same time, the plastic deformation is the achievement of a defined Minimum clamping force safe.

The resistance to this deformation causes in a similar manner as in the embodiments described above, the axial tension between the two sleeve parts, wherein the plastic deformation for a pronounced Plateau ensures constant elasticity.

Figure 5 shows a socket joint for such applications, where the male and Female-cup parts are not or only to a limited extent rotatable or where they are from others Reasons can not be bolted together directly. The Male and Female-sleeve parts have the same structure as in Figure 1, but that is Male sleeve part 1 equipped with a deformable projection 36 according to FIG.

It is essential that between the male-female part 1 and the female-female part 10 a threaded rod 40 is arranged, the external thread 41 of the external thread 34 corresponds to the male-female part and that on the threaded rod 40 a relatively long nut 50 and two lock nuts 60 and 70 are arranged are.

The screwing of male and female female part 1 and 10 will now be as follows First, the threaded rod 40 in the right female socket part 10 screwed in, about as far as the lock nut 70 on the front page of the female socket part rests. Subsequently, the lock nut 70 is tightened so far, that is arranged on its right flank deformable projection 36 is plastically deformed, as shown in Figure 4 (c). This is the desired Tension between the threaded rod 40 and the female socket part 10 guaranteed.

Then, the union nut 50 is screwed to the left until the thread 34th the male-female part 1 is detected and finally on the deformable projection 36 of this sleeve part abuts (the threaded rod 40 is in reality longer than shown in the drawing). The nut 50 is then so strong attracted, that the deformable projection 36 plastically deformed as described is, so that here, the tension between the male-female part. 1 and the union nut 50 is ensured.

Now it lacks the tension between the nut 50 and the threaded rod 40. This is the second lock nut 60. It will against the still screwed free end of the union nut and tightened until its projection 36 indicates the deformation described.

This is also when screwing the sleeve parts with the help of bridging parts in all threaded connections involved in load transfer, the induced tension according to the invention.

Of course it would also be possible to use bridging parts, the deformable protrusions exclusively at the bridging parts provided. This would need only the deformable projection 36 of male-female part 1 to be moved to the left end of the union nut 50.

In the embodiments, the projection is shown as an annular part; but instead, several local projections are conceivable.

In summary, therefore, by a targeted, automatically resulting deformation a projection - optionally in conjunction with a stop line generates defined tension, as previously only by means of a torque wrench was possible. In particular, in plastic deformation of the projection the preload force can be almost independent of the preload path (joint opening) keep at a constant value.

Claims (15)

1. Sleeve connection comprising a male sleeve component (1, 30) and a female sleeve component (10, 20) for steel reinforcing bars, wherein the steel reinforcing bars are each connectible, at their end being joined, to one end of the male or female sleeve component (1, 10, 20, 30), and the male sleeve component (1, 30) has at its other end a pin (5, 33) having an external thread (6, 34), while the female sleeve component (10, 20) has at its other end a bore (11, 21) having an internal thread, so that the two sleeve components (1, 10, 20, 30) can be screwed together,
   and wherein the male (1, 30) or the female (10, 20) sleeve component has at least one projection (15, 22, 36) which is so deformable by the screwing together of the two sleeve components (1, 10, 20, 30) that the resistance of the projection (15, 22, 36) acting against deformation brings about an axial prestressing force between the threads of the two sleeve components (1, 10, 20, 30),
   characterised in that
   the deformable projection (15, 22, 36) is arranged on an end face (4, 13, 23, 32) of one sleeve component, which end face, after the components have been screwed together, rests against a corresponding end face of the other sleeve component.
2. Sleeve connection according to claim 1,
   characterised in that
   the deformable projection (15, 22, 36) projects axially in the direction towards the other sleeve component.
3. Sleeve connection according to claim 2,
   characterised in that
   the end faces (4, 13, 23, 32) are arranged terminally on the male and female sleeve components.
4. Sleeve connection according to one or more of the preceding claims,
   characterised in that
   the deformable projection (15) is formed from resilient material, especially rubber.
5. Sleeve connection according to one or more of the preceding claims,
   characterised in that
   the deformable projection is in the form of a ring (15) partly inserted in a groove (14).
6. Sleeve connection according to one or more of the preceding claims,
   characterised in that
   the deformable projection is in the form of a projecting edge of material (22), especially a milled edge.
7. Sleeve connection according to claim 6,
   characterised in that
   the edge of material (22) projects obliquely.
8. Sleeve connection according to claim 6 or 7,
   characterised in that
   a recess (25) is arranged axially behind the edge of material (22); and the edge of material (22), after its deformation, lies in that recess (25).
9. Sleeve connection according to claim 6, 7 or 8,
   characterised in that
   the edge of material (22) is in the form of a ring, and the recess (25) is in the form of a groove.
10. Sleeve connection according to one or more of the preceding claims,
    characterised in that
    the deformable projection (36) is formed integrally with the male (1, 30) or female (10, 20) sleeve component.
11. Sleeve connection according to one or more of the preceding claims,
    characterised in that
    the deformable projection (36) is directed substantially radially outwards.
12. Sleeve connection according to one or more of the preceding claims,
    characterised in that
    the deformable projection (15, 22, 36) is so formed that screwing together the two sleeve components (1, 10, 20, 30) achieves a defined axial prestressing force.
13. Sleeve connection according to claim 12,
    characterised in that
    the defined prestressing force comes into effect after the two sleeve components (1, 10, 20, 30) have been screwed together until seamless contact of the two end faces (4, 13, 23, 32) or of the projection (22) with a neighbouring end face is obtained.
14. Sleeve connection according to any one of the preceding claims,
    characterised in that
    the two sleeve components (1, 10, 20, 30) can be screwed together by way of intermediately arranged bridging members (40, 50, 60, 70); and deformable projections (15, 22, 36) are arranged on the bridging members (40, 50, 60, 70) or on the sleeve components (1, 10, 20, 30), as desired.
15. Sleeve connection according to claim 14,
    characterised in that
    the bridging members consist of a threaded rod (40), a long sleeve nut (50) and two lock nuts (60, 70).

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