MECHANICAL CONNECTION COMPONENT WITH A PRESSURE INDICATOR

Abstract

The invention relates to a mechanical connection component for connecting a first element (1) to a second element (2). The connection component can be brought from an untensioned position into a tensioned position by exerting a clamping force (F), wherein a pressure pin (7) with a head portion (8) is arranged in a recess of the connection component (5), and a pressure indicator (9) is arranged or can be arranged in the region of the head portion (8). The head portion (8) is arranged so as to exert pressure onto the pressure indicator (9) in the untensioned position of the connection component (5) and not exert any pressure onto the pressure indicator (9) or exert a reduced pressure in comparison to the untensioned position when the connection component (5) is in the tensioned position.

Claims

1. A mechanical connecting component for connecting a first element (1) to a second element (2) by exerting a clamping force (F), comprising a first clamping region (3) and a second clamping region (4), which is arranged at a distance from the first clamping region (3), wherein an expansion region (21) is arranged between the first clamping region (3) and the second clamping region (4), characterized in that the connecting component can be moved from an unclamped position to a clamped position by exerting the clamping force (F), the length of the expansion region (21) increasing when the clamping force (F) is exerted, in that an elongated recess (6) extends in the interior of the connecting component (5) at least in the expansion region (21), in that a pressure pin (7) is arranged at least partially inside the recess (6), the pressure pin (7) comprising a head section (8), and the pressure pin (7) being connected to the connecting component at one end and not being connected to the connecting component at its other end, and in that a pressure indicator (9) can be or is arranged in the region of the head section (8), the head section (8) being arranged in such a way as to exert pressure on the pressure indicator (9) in the unclamped position of the connecting component and to exert no pressure or a pressure which is reduced in comparison with the unclamped position on the pressure indicator (9) in the clamped position of the connecting component.

2. The connecting component according to claim 1, characterized in that the recess (6) extends from the first clamping region (3) to the second clamping region (4).

3. The connecting component according to claim 1 or 2, characterized in that the pressure pin (7) extends from the first clamping region (3) to the second clamping region (4), and in that one end of the pressure pin (7) is connected to the connecting component in the first clamping region (3) and is not connected to the connecting component in the second clamping region (4).

4. The connecting component according to one of claims 1 to 3, characterized in that the pressure indicator (9) comprises or is made of a piezochromic material.

5. The connecting component according to claim 4, characterized in that the piezochromic material is a piezochromic polymer composite, in particular comprising or consisting of a polymeric matrix material in which a piezochromic substance is contained.

6. The connecting component according to one of claims 1 to 5, characterized in that a cover element (12) is provided, which can be or is connected to an end region (11) of the connecting component, wherein the pressure indicator (9) is arranged on the cover element (12), or wherein the pressure indicator (9) is arranged on the head section (8) of the pressure pin (7).

7. The connecting component according to claim 6, characterized in that the cover element (12) is formed such that it is substantially flush with the connecting component (5).

8. The connecting component according to one of claims 1 to 7, characterized in that the cover element (12) has an at least partially transparent protective plate (13) on the side facing away from the head section (8).

9. The connecting component according to claim 8, characterized in that the protective plate (13) is made of an elastic material.

10. The connecting component according to one of claims 1 to 9, characterized in that the recess (6) is arranged parallel to the longitudinal extension direction (10) of the connecting component (5), preferably centrally along a central longitudinal axis of the connecting component (5).

11. The connecting component according to one of claims 1 to 10, characterized in that the pressure pin (7) is arranged parallel to the longitudinal extension direction (10) of the connecting component (5), preferably centrally along a central longitudinal axis of the connecting component (5).

12. The connecting component according to one of claims 1 to 11, characterized in that the pressure pin (7) is substantially rigidly and/or non-displaceably connected to the connecting component (5) at its end opposite the head section (8) by a retaining means (14).

13. The connecting component according to claim 12, characterized in that the retaining means (14) is a polymer material (15) in which the end opposite the head portion (8) of the pressure pin (7) is embedded and/or molded.

14. The connecting component according to claim 12, characterized in that the retaining means (14) is a magnetic retaining element (16), and in that the pressure pin (7) has a magnetic and/or a ferromagnetic material at least at its end opposite the head section (8).

15. The connecting component according to one of claims 1 to 14, characterized in that the pressure pin (7) has, at its end opposite the head portion (8), a conically tapering region, in particular a tip (17).

16. The connecting component according to one of claims 1 to 15, characterized in that the clamping force (F) can be or is generated by at least one clamping nut (19) arranged in the second clamping region (4).

17. The connecting component according to one of claims 1 to 16, characterized in that the first clamping region (3) can be or is rigidly connected to the first element (1) by bonding, welding and/or casting.

18. The connecting component according to one of claims 1 to 16, characterized in that the connecting component in the first clamping region (3) has a projection (18) and/or a fastening nut for positive connection to the first element (1), so that the connecting component can be partially inserted into a clearance (20) of the first element (1).

19. An arrangement comprising a connecting component according to one of claims 1 to 18 and a first element (1) and a second element (2), wherein a clearance (20) is provided in the first element (1) or in the second element (2), which is suitable for passing through and/or inserting the connecting component (5).

20. The arrangement according to claim 19, characterized in that the connecting component (5) is arranged to be freely movable at least in the expansion region (21) within the clearance (20).

21. A system comprising a connecting component according to one of claims 1 to 18 and a cover element (12), which is connected to the connecting component (5).

Description

[0040] In the following, the invention will be discussed in detail with reference to exemplary embodiments. The exemplary embodiments merely show preferred variants of the invention, but are not intended to limit the scope of protection in any way. In the figures:

[0041] FIG. 1 shows a schematic view of a first exemplary embodiment of the invention;

[0042] FIG. 2 shows a detailed view of a region of FIG. 1; and

[0043] FIG. 3 shows a schematic view of a second exemplary embodiment of the invention.

[0044] FIG. 1 shows a schematic view of a first exemplary embodiment of the invention, wherein the connecting component 5 is used to connect a first element 1 and a second element 2. In the present exemplary embodiment, the connecting component is a threaded rod.

[0045] In this exemplary embodiment, the first element 1 is a solid concrete body with a clearance 20 in the form of a bore, into which the connecting component 5 is inserted with its first clamping region 3 and part of the expansion region 21. In this exemplary embodiment, the expansion region 21 extends substantially in the region of the bandage 22, the height of the second element 2 and the height of the washer 23. The first clamping region 3 is bonded to the clearance 20 of the first element 1, so that the connecting component 5 is fixedly connected to the first element 1. The expansion region 21 is not fixedly connected to the clearance 20 of the first element 1. A bandage 22 is provided in the expansion region 21 to reduce friction between the element 1 and the connecting component 5 to a certain extent, thereby increasing the expansion region 21. The bandage 22 does not provide a substantial non-positive connection between the clearance 20 and the fastening bolt 5.

[0046] In other exemplary embodiments not shown, the bandage 22 may also be omitted, thereby rigidly connecting the connecting component 5 to the first element 1 over a larger region. As a result, the effective length of the expansion region 21 decreases and the first clamping region 3 increases.

[0047] The second element 2 in this embodiment is a steel plate which also has a clearance 20 in the form of a bore. The connecting component 5 extends completely through the clearance 20. A recess 6 is provided within the connecting component 5, which extends in the longitudinal extension direction 10 of the connecting component. A pressure pin 7, which has a widened head section 8 at one end, is arranged in the recess. At its other end, the pressure pin 7 has a tip 17, which serves to facilitate the insertion of the pressure pin 7 into the recess 6.

[0048] In the region of the tip 17, the pressure pin 7 is connected to the connecting component 5 via a retaining means 14. The retaining means 14 is made of a polymer material 15 which is introduced into the recess 6 in an uncured state and hardens there after positioning of the pressure pin 7, thereby fastening the pressure pin 7 in a substantially non-displaceable manner. The pressure pin 7 is fixedly connected to the connecting component 5 only in the region of one end, in this exemplary embodiment that end at which the tip 17 is arranged.

[0049] At the end of the connecting component 5 that is adjacent to the second clamping region 4, a cover element 12 is arranged that is designed as a screw-on cap nut. In its center, the cover element 12 has a pressure indicator 9 on the inside, which in this exemplary embodiment is designed as a foil made of a piezochromic polymer material. The pressure indicator 9 is colored blue when not pressurized, i.e. at atmospheric pressure, while it is colored red at an increased pressure, in particular at a pressure greater than 10 N/cm.sup.2.

[0050] The pressure indicator 9 is covered by a protective plate 13 made of transparent plexiglass. In addition, a view clearance 24 is provided in the cover element 12 to allow a clear view of the pressure indicator 9 through the protective plate 13.

[0051] In FIG. 1, the cover element 12 is flush with the connecting component 5, in particular with the open end of the recess 6.

[0052] The pressure pin 7 has a suitable length such that, in the unclamped state of the fastening bolt 5, it projects about 0.2 mm beyond the end of the bolt 5. Therefore, when the cover element 12 is fully screwed on, the head section 8 exerts pressure on the pressure indicator 9. In this condition, the pressure indicator is colored red.

[0053] The clamping force F is generated by two clamping nuts 19. A washer 23 is arranged between the second element 2 and a clamping nut 19.

[0054] When the clamping nut 19 is tightened, i.e. when the clamping force F is increased, elongation of the expansion region 21 occurs, wherein the position of the head section 8 of the pressure pin 7 remains substantially unchanged. As a result, the pressure exerted by the head section 8 on the pressure indicator 9 is reduced, and when the pressure falls below the level required for the color change, i.e. in particular when the contact between the pressure indicator 9 and the head section 8 ceases, the color of the pressure indicator changes to blue. This corresponds to the clamped position of the connecting component 5 shown in FIG. 1.

[0055] The clamping force F causes the first element 1 and the second element 2 to be connected to one another in a non-positive manner. The clamping force F correlates with the elongation of the expansion region 21 of the connecting component 5. When the clamping force F decreases, the elongation of the expansion region 21 is also reduced.

[0056] If the clamping nuts 19 were to loosen and the clamping force F were to decrease as a result, the head section 8 of the pressure pin 7 would press against the pressure indicator 9 again, which would result in a color change of the piezochromic material. When checking the connection, the red color would immediately indicate that the clamping force F has decreased.

[0057] With suitable adjustment, detection may already be possible when the fastening nuts 19 are not completely loosened, i.e. at a time when loosening of the connection would not yet be detectable by manual inspection. The connection can then be strengthened again by tightening the fastening nuts 19. Preferably, tightening continues until the color change of the pressure indicator 9 again indicates sufficient clamping force F.

[0058] FIG. 2 shows a detailed view of the region A in FIG. 1, with the head section 8 and the cover element 9 shown in detail. The function has already been explained above, so the individual elements are not described in detail here.

[0059] FIG. 3 shows a schematic view of a second exemplary embodiment of the invention, wherein, compared to the first embodiment, also the first element 1 is a steel plate. Both the first element 1 and the second element 2 have the clearances 20, through which the connecting component 5 passes. The connecting component 5 has a projection 18 on the side of the first element 1 so that it cannot slip through the clearance 20. The application of the clamping force F is analogous to the first exemplary embodiment and will not be explained again here.

[0060] A further difference compared to the first exemplary embodiment is the way in which the pressure pin 7 is fastened in the recess 6 of the fastening bolt 5. A retaining means 14 in the form of a magnetic retaining element 16 is arranged at the lower end of the recess 6. The magnetic retaining element is a piece of a permanent magnet. The rest of the bolt 5 is made of stainless steel with an austenitic structure, so that it is not magnetic. The pressure pin 7 is made of ferromagnetic material and is therefore attracted by the magnetic retaining element 16. As a result, the pressure pin 7 is firmly positioned in the recess 6.

[0061] In an embodiment of the second exemplary embodiment not shown, the recess 6 may extend substantially over the full length of the connecting component 5. In this case, the pressure pin 7 may be fixed in the region of the projection 18 of the connecting component 5.

LIST OF REFERENCE SIGNS

[0062] 1 first element

[0063] 2 second element

[0064] 3 first clamping region

[0065] 4 second clamping region

[0066] 5 connecting component

[0067] 6 recess

[0068] 7 pressure pin

[0069] 8 head section

[0070] 9 pressure indicator

[0071] 10 longitudinal extension direction

[0072] 11 end region

[0073] 12 cover element

[0074] 13 protection plate

[0075] 14 retaining means

[0076] 15 polymer material

[0077] 16 magnetic retaining element

[0078] 17 tip

[0079] 18 projection

[0080] 19 clamping nut

[0081] 20 clearance

[0082] 21 expansion region

[0083] 22 bandage

[0084] 23 washer

[0085] 24 view clearance

[0086] F clamping force