PIPE JOINT

Abstract

The invention relates to a pipe coupling (1), comprising a coupling body (2), a nut (3) which can be screwed onto or into the coupling and has a conical hole (32) extending in the direction of the coupling body (2), and a pipe (4) which is guided through the hole (33) in the nut and has a shaped part (41) protruding outward with two clamping surfaces (42, 43), wherein the first clamping surface (42) is parallel to the end face (22) of the coupling body (2) and is supported on the coupling body (2) at least in certain regions when the pipe coupling (1) is in the clamped state, and the second clamping surface (43) is conical in shape corresponding to the conical hole (32) in the nut (3) and is supported in the conical hole (32) in the nut (3), wherein the coupling body (2) has a radially circumferential cut by which a retaining space (6) is created for the washer (5) which is limited by the first clamping surface (42), wherein the washer (5) has a symmetrical, polygonal cross-section. In addition, the invention relates to a washer for connecting such pipes.

Description

[0001] SEALING RING AND PIPE CONNECTION

[0002] The invention relates to a pipe connection according to the preamble of patent claim 1. The invention further relates to a sealing ring for a pipe connection according to patent claim 7.

[0003] For the implementation of pipe fittings, pipe connections are known that comprise a connecting body that receives the pipe end to be connected and onto which a nut can be screwed. The connecting body has a cylindrical bore for receiving the pipe end, wherein the pipe end is provided with an outwardly projecting formation, the first clamping surface of which rests against the end face of the connecting body. A second clamping surface of the formation is conical and rests against a conical bore of the nut. By tightening the screw connection between the nut and the connecting body, the projecting formation can be pressed against the end face of the connecting body.To seal the connecting body against the pipe it accommodates, the connecting body is provided with a conical bore extending to the end face of the connecting body and widening toward the end face, thereby forming a receptacle for a sealing ring between the connecting body and the pipe. The sealing ring has a substantially triangular cross-section corresponding to the receptacle. Such a pipe connection is known, for example, from DE 195 26 316 A1.

[0004] In the case of pipe connections of the aforementioned type, depending on the design of the sealing ring, the sealing ring may be twisted or even completely turned inside out during assembly, which may impair the sealing effect and the durability of the sealing ring.

[0005] The invention aims to remedy this situation. The invention is based on the object of providing a pipe connection of the aforementioned type that can be manufactured with minimal effort and in which twisting or turning over of the sealing ring is avoided. According to the invention, this object is achieved by the features of the characterizing part of patent claim 1.

[0006] The invention provides a pipe connection of the aforementioned type in which twisting or inversion of the sealing ring is prevented. The fact that the sealing ring has a polygonal, symmetrical cross-section ensures that a force applied to one side generates a corresponding opposing force, thereby achieving a symmetrical pressure distribution in the sealing ring. It has been shown that a polygonal sealing ring with a symmetrical pressure distribution is significantly less prone to twisting or inversion. Furthermore, the sealing ring fulfills its function even when turned inside out.

[0007] Preferably, the recess is formed by a conical bore extending up to the end face of the connecting body, widening in the direction of the end face, which opens at its smallest diameter into a cylindrical bore of the connecting body, the inner diameter of which preferably corresponds substantially to the outer diameter of the end section of the pipe received by the connecting piece.

[0008] In a further development of the invention, the first clamping surface of the tube transitions into a connecting surface that tapers conically toward the cylindrical end section of the tube. This creates an angled transition to accommodate the apex line of the sealing ring, enabling stable positioning of the sealing ring.

[0009] In one embodiment of the invention, the sealing ring has a pentagonal or hexagonal cross-section. This creates contact sides for sealing the sealing surfaces of a pipe connection, which are connected via apex lines that enable the generation of directed restoring forces. Alternatively, the cross-section of the sealing ring can also have more than six corners. In this case, the term "corner" or "angular" also includes a radius that connects two surfaces positioned at an angle to one another. A "apex line" is understood here to mean a linear outer corner created by the angular positioning of two planes (corresponding to the ridge of a gable roof).

[0010] In a further embodiment of the invention, the cross-section of the sealing ring is hexagonal, with the cross-section being formed by two parallel, outwardly angled base sides, like a gable roof, which are connected to each other via two outer sides that are shorter than the base sides. Preferably, the corners of the cross-section of the sealing ring are rounded over a radius.

[0011] The invention is further based on the object of providing a sealing ring for a pipe connection of the aforementioned type, which can be manufactured with minimal effort and in which twisting or inversion of the sealing ring is avoided. According to the invention, this object is achieved by the features of the characterizing part of patent claim 7.

[0012] In one embodiment of the invention, the cross-section is pentagonal or hexagonal. Preferably, the cross-section is hexagonal, with the cross-section being formed by two parallel, outwardly angled base sides, like a gable roof, which are connected to each other by two outer sides that are shorter than the base sides. The corners of the cross-section are preferably rounded along a radius.

[0013] Further developments and refinements of the invention are specified in the remaining subclaims. An embodiment of the invention is illustrated in the drawings and described in detail below. They show:

[0014] Figure 1 shows a schematic representation of a pipe connection;

[0015] Figure 2 shows an enlarged detail of section II from Figure 1;

[0016] Figure 3 shows the schematic representation of the sealing ring of the pipe connection from Figure 1 and Figure 4 shows the enlarged detailed representation of section IV of the sealing ring from Figure 3.

[0017] The pipe connection 1 chosen as an embodiment essentially consists of a connecting body 2 which receives a pipe 4 and onto which a nut 3 is screwed, wherein a sealing ring 5 is arranged between the pipe 4 and the connecting body 2.

[0018] The connecting body 2 is partially shown in Figure 1, specifically with regard to the connection of the end section of the pipe 4. The further end can be provided again according to this illustration, so that the connecting body 2 serves to connect two pipes. Alternatively, it can also be provided with a thread at its end (not shown) for connection to or into a threaded piece. An external thread 21 for screwing on the nut 3 is arranged around the outside of the connecting body 2 and extends up to its end face 22. Along its central axis, the connecting body 2 has a through-bore 25 which opens into a cylindrical bore 24 with an enlarged diameter, which is adjoined by a conical bore 23 which is designed to widen in the direction of the end face 22.

[0019] The nut 3, which is provided with an internal thread 31 for this purpose, is screwed onto the external thread 21 of the connecting body 2. The nut 3 has a conical bore 32 that widens toward the connecting body 2. Adjacent to the conical bore 32 of the nut 3 is a through-bore 33 through which the pipe 4 is passed.

[0020] A recess 41 is formed into the end section of the tube 4, whose outer diameter essentially corresponds to the inner diameter of the cylindrical bore 24 of the connecting body 2. The recess 41 has a first clamping surface 42, which is positioned essentially orthogonally to the rotational center axis of the tube 4 and which bears against the end face 22 of the connecting body 2. The first clamping surface 42 merges into a connecting surface 44, which tapers conically toward the cylindrical end section 45.

[0021] The second clamping surface 43, opposite the first clamping surface 42, is conical, the shape of this second clamping surface 43 essentially corresponding to the conical bore 32 of the nut 3, against which the formation 41 with the second clamping surface 43 rests.

[0022] An annular receiving space 6 with a substantially quadrangular cross-section for receiving the sealing ring 5, which is pushed onto the pipe 4, is delimited by the conical bore 23 of the connecting body 2 and the end section of the pipe 4 with its first clamping surface 4 and its connecting surface 45.

[0023] The sealing ring 5 is shown enlarged in Figures 3 and 4. It has a substantially hexagonal cross-section formed from two parallel, gable-roof-like base sides that are angled outwards and connected to one another via two shorter outer sides. As a result, the sealing ring 5 has four wide sealing surfaces 52, each tapering outwards from an apex line 51, which terminate in one of two parallel, straight, narrow sealing surfaces 53. The "corners" of the hexagonal cross-section are rounded over a radius 54. In the exemplary embodiment, the sealing ring is made of rubber. It can also be made of another elastomer material.

[0024] As can be seen in particular from Figure 2, the sealing ring 5 rests with a narrow sealing surface 53 against the first clamping surface 42 of the formation 41 of the tube 4 and runs with a wide sealing surface 52 of its inner contour along the connecting surface 44. The second wide sealing surface 52 of the inner contour of the sealing ring 5 rests against the cylindrical end section 45, with the apex line 51 formed between these two inner wide sealing surfaces 52 resting in the angular transition between the connecting surface 44 and the cylindrical section 45. The two outer wide sealing surfaces 52 of the sealing ring 5 are pressed against the inner wall of the conical bore 23 in such a way that they form a common flat surface.The resulting restoring forces press the sealing ring against the transition between the connecting surface 44 and the cylindrical section 45, as well as against the sealing gap between the end face 22 of the connecting body 2 and the first clamping surface 42 of the pipe 4. This design reliably prevents extrusion into the gap as well as distortion of the sealing ring 5. In the exemplary embodiment, the cross-section of the sealing ring 5 is designed as a symmetrical hexagon. Depending on the design of the sealing gap, the cross-section can also have a different symmetrical polygonal shape.

Claims

- 7 - Patent claims 1. Pipe connection (1) with a connecting body (2), a nut (3) that can be screwed onto or into the connecting body (2) and which has a conical bore (32) that widens in the direction of the connecting body (2), and a pipe (4) that passes through a bore (33) in the nut and which has an outwardly projecting projection (41) with two clamping surfaces (42, 43), of which a first clamping surface (42) is parallel to the end face (22) of the connecting body (2) and is supported at least partially on the connecting body (2) in the clamped state of the pipe connection (1), and the second clamping surface (43) is conically shaped according to the conical bore (32) of the nut (3) and is supported in the conical bore (32) of the nut (3), wherein the connecting body (2) has a radially circumferential recess through which a receiving space (6) for a sealing ring (5) is formed, which is bounded by the first clamping surface (42), characterized in that the sealing ring (5) has a polygonal, symmetrical cross-section 2. Pipe connection according to claim 1, characterized in that the recess is formed by a conical bore (23) extending to the end face (22) of the connecting body (2) and widening in the direction of the end face (22), which opens at its smallest diameter into a cylindrical bore (24) of the connecting body (2), the inner diameter of which preferably corresponds substantially to the outer diameter of the end section of the pipe (4) received by the connecting piece (2).

3. Pipe connection according to claim 1 or 2, characterized in that the first clamping surface (42) of the pipe (4) is formed into a connecting surface (44) transitions, which conically towards the cylindrical end section (45) of the pipe (4). - 8 - 4. Pipe connection according to one of the preceding claims, characterized in that the cross-section of the sealing ring (5) is pentagonal or hexagonal.

5. Pipe connection according to claim 4, characterized in that the cross-section of the sealing ring (5) is hexagonal, wherein the cross-section is formed from two base sides parallel to each other, angled outwards in a saddle-roof manner, which are connected to each other via two outer sides which are shorter than the base sides.

6. Pipe connection according to claim 5, characterized in that the corners of the cross-section of the sealing ring (5) are rounded over a radius (54).

7. Sealing ring (5) for a pipe connection (1) according to one of the preceding claims, characterized in that it has a polygonal, symmetrical cross-section.

8. Sealing ring according to claim 7, characterized in that the cross-section is pentagonal or hexagonal.

9. Sealing ring according to claim 8, characterized in that the cross-section is hexagonal, wherein the cross-section is formed from two base sides parallel to each other, angled outwards in a saddle-like manner, which are connected to each other via two outer sides which are shorter than the base sides.

10. Sealing ring according to claim 9, characterized in that the corners of the cross-section are rounded over a radius (54).

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