Tube Connector

Abstract

A tube connector for attachment to an end of a tube of a pressurized fluid system has a housing, a main sealing element, a gripping element and a cone element. The main sealing element is arranged for sealing an inner surface of the housing to an outer surface of a tube. The gripping element comprises a gripping edge for engaging with an outer surface of a tube. The cone element limits a movement of the grip-ping element. The tube connector further has an integrated release element. The release element has a tubular part, a top part and an environmental sealing. A release edge of the tubular part engages with the gripping element and the environmental sealing is adapted for sealing a receptacle formed in the housing of the environment.

Claims

1. A tube connector (1) for attachment to a tube (7) of a pressurized fluid system, wherein the tube connector (1) comprises: a housing (3), a main sealing element (9), a gripping element (11) and a cone element (13), the housing (3) comprising a receptacle (5) for receiving the tube (7), the receptacle (5) being delimited by an insertion end (21) for which the tube (7) can be inserted into the receptacle (5), and an abutment end (23) for delimiting a maximum insertion of the tube (7) into the housing (3), the main sealing element (9) being provided for preventing a fluid from flowing out of a pressurized fluid system at a connection of the tube (7) and the tube connector (1), the gripping element (11) comprising a passage (12) for receiving the tube (7), the gripping element (11) being arranged in the receptacle (5) and comprising a gripping edge (25) for engaging with an outer surface (24) of the tube (7) received in the passage (12) of the gripping element (11), the cone element (13) being arranged in the receptacle (5) for delimiting a movement of the gripping element (11) towards the insertion end (21), the tube connector (1) further comprising an integrated release element (15) arranged at least partially in the receptacle (5) and movable along a direction pointing from the insertion end (21) to the abutment end (23), the release element (15) comprising a passage (36) for the tube (7), a tubular part (31) and an environmental sealing element (35), a release edge (37) of the tubular part (31) being adapted for engaging with the gripping element (11) and moving the gripping element (11), such that the gripping element (11) releases the tube (7) inserted into the passage (12) of the gripping element (11), the environmental sealing element (35) providing a sealing of the receptacle (5) from an environment, and the environmental sealing element (35) being adapted for sealing the release element (15) towards an inner surface (19) of the housing (3) and towards the outer surface (24) of the tube (7) inserted into the passage (36) of the release element (15).

2. A tube connector (1) according to claim 1, wherein the integrated release element (15) comprises a top part (33) providing an actuation surface for pushing the release element (15) towards the abutment end (23).

3. A tube connector (1) according to claim 2, wherein the environmental sealing element (35) is formed in one piece and from a first plastic material.

4. A tube connector (1) according to claim 2, wherein the top part (33) and the tubular part (31) are formed in one piece and from a second plastic material, the first plastic material differing from the second plastic material.

5. A tube connector (1) according to claim 3, wherein the tubular part (31) and the top part (33) are connected by at least four evenly distributed bridge parts (46), the bridge parts (46) being formed from the second plastic material and gaps (44) between the bridge elements (46) being filled with the first plastic material.

6. A tube connector (1) according to claim 2, wherein the top part (33) of the release element (15) forms a collar (39) extending at least partly between the cone element (13) and the inner surface (19) of the housing (3), a first protrusion (41) is formed at the top part (33) and a second protrusion (43) is formed at the cone element (13), wherein the first protrusion (41) and the second protrusion (43) are adapted to engage for delimiting a maximum movement of the release edge (37) in a direction away from the abutment end (23) to a first predefined distance.

7. A tube connector (1) according to claim 6, wherein the cone element (13) comprises a third protrusion (45), wherein the first protrusion (41) and the third protrusion (45) are adapted to engage for delimiting a maximum movement of the release edge (37) in a direction away from the abutment end (23) to a second predefined distance, wherein the second predefined distance is less than the first distance.

8. A tube connector (1) according to claim 6, wherein the first protrusion (41), the second protrusion (43) and/or the third protrusion (45) are adapted to provide a direct load path from the cone element (13) via the environmental sealing element (35) to the inner surface (19) of the housing (3).

9. A tube connector (1) according to claim 1, wherein the cone element (13) and the release element (15) are formed such that a load due to a radial extension of the tube (7) inserted into the passage (36) of the release element (15) is transferred via the cone element (13) and the environmental sealing element (35) to the inner surface (19) of the housing (3).

10. A tube connector (1) according to claim 1, wherein the release edge (37) of the tubular part (31) is adapted for engaging with the gripping element (11) and moving the gripping element (11) towards the abutment end (23) and/or away from the tube (7) inserted into the passage (12) of the gripping element (11), and the gripping element (11) preferably comprises an inclined surface (27) such that a width of the passage (12) for the tube (7) formed by the gripping element (11) increases in a direction pointing from the abutment end (23) to the insertion end (21).

11. A tube connector (1) according claim 1, wherein the tube connector (1) further comprises a support sleeve (17) for receiving an end of the tube (7) inserted into the receptacle (5).

12. A tube connector (1) according to claim 1, further comprising a biasing means (55) for biasing the release element (15) in a direction pointing away from the abutment end (23).

13. A tube connector (1) according to claim 1, wherein the environmental sealing element (35) is adapted for engaging with the tube (7) that is inserted into the passage (36) of the release element (15) such that the release element (15) moves in the same direction as the tube (7) inserted into the receptacle (5).

14. A tube connector according to claim 1, wherein the main sealing element (9) comprises a passage (10) for receiving the tube (7) and wherein the main sealing element (9) is arranged in the receptacle (5) for providing a sealing between an inner surface (19) of the housing (3) and an outer surface (24) of the tube (7) received in the passage (10) of the main sealing element (9).

15. A tube connector (1) according to claim 3, wherein the top part (33) and the tubular part (31) are formed in one piece and from a second plastic material, the first plastic material differing from the second plastic material.

16. A tube connector (1) according to claim 4, wherein the tubular part (31) and the top part (33) are connected by at least four evenly distributed bridge parts (46), the bridge parts (46) being formed from the second plastic material and gaps (44) between the bridge elements (46) being filled with the first plastic material.

17. A tube connector (1) according to claim 3, wherein the top part (33) of the release element (15) forms a collar (39) extending at least partly between the cone element (13) and the inner surface (19) of the housing (3), a first protrusion (41) is formed at the top part (33) and a second protrusion (43) is formed at the cone element (13), wherein the first protrusion (41) and the second protrusion (43) are adapted to engage for delimiting a maximum movement of the release edge (37) in a direction away from the abutment end (23) to a first predefined distance.

18. A tube connector (1) according to claim 7, wherein the first protrusion (41), the second protrusion (43) and/or the third protrusion (45) are adapted to provide a direct load path from the cone element (13) via the environmental sealing element (35) to the inner surface (19) of the housing (3).

19. A tube connector (1) according to claim 2, wherein the cone element (13) and the release element (15) are formed such that a load due to a radial extension of the tube (7) inserted into the passage (36) of the release element (15) is transferred via the cone element (13) and the environmental sealing element (35) to the inner surface (19) of the housing (3).

20. A tube connector (1) according to claim 2, wherein the release edge (37) of the tubular part (31) is adapted for engaging with the gripping element (11) and moving the gripping element (11) towards the abutment end (23) and/or away from the tube (7) inserted into the passage (12) of the gripping element (11), and the gripping element (11) preferably comprises an inclined surface (27) such that a width of the passage (12) for the tube (7) formed by the gripping element (11) increases in a direction pointing from the abutment end (23) to the insertion end (21).

21. A tube connector (1) according claim 2, wherein the tube connector (1) further comprises a support sleeve (17) for receiving an end of the tube (7) inserted into the receptacle (5).

22. A tube connector (1) according to claim 2, further comprising a biasing means (55) for biasing the release element (15) in a direction pointing away from the abutment end (23).

23. A tube connector (1) according to claim 2, wherein the environmental sealing element (35) is adapted for engaging with the tube (7) that is inserted into the passage (36) of the release element (15) such that the release element (15) moves in the same direction as the tube (7) inserted into the receptacle (5).

24. A tube connector according to claim 2, wherein the main sealing element (9) comprises a passage (10) for receiving the tube (7) and wherein the main sealing element (9) is arranged in the receptacle (5) for providing a sealing between an inner surface (19) of the housing (3) and an outer surface (24) of the tube (7) received in the passage (10) of the main sealing element (9).

Description

[0040] In the following preferred embodiments of the invention are further described in more detail with reference to the Figures, wherein

[0041] FIG. 1 shows a partially sectional and partially perspective view of a first exemplary embodiment of a tube connector according to the present invention,

[0042] FIG. 2a shows a sectional view of a release element of the exemplary embodiment of a tube connector shown in FIG. 1,

[0043] FIG. 2b shows a sectional view of the release element of FIG. 2a without an environmental sealing element,

[0044] FIG. 2c shows a top view of the release element of FIGS. 2a and 2b,

[0045] FIG. 2d shows a top view of the release element of FIGS. 2a, 2b and 2c without the environmental sealing,

[0046] FIG. 3 shows a sectional view of a second exemplary embodiment of a tube connector according to the present invention and

[0047] FIG. 4 shows a sectional view of a third exemplary embodiment of a tube connector according to the present invention.

[0048] Throughout the different embodiments shown in the Figures like elements will be denoted with like reference numerals.

[0049] In FIG. 1 a first embodiment of a tube connector 1 according to the present invention is shown. The tube connector 1 comprises a housing 3 having a cavity or receptacle 5 for receiving a tube 7 and several elements 9, 11, 13, 15. The tube 7 and, hence, also the tube connector 1 are part of a pressurized fluid system which is used for conducting a pressurized fluid, such as a braking system of a vehicle. The fluid can, for example, be air or hydraulic oil. The elements 9, 11, 13, 15 arranged in the receptacle 5 are a main sealing element 9, a gripping element 11, a cone element 13 and an integrated release element 15. Also arranged inside the receptacle 5 is a support sleeve 17, which stiffens or supports a flexible tube 7 once it has been fully inserted into the receptacle 5 of the tube connector 1. The tube 7 shown in FIG. 1 inside the tube connector 1 is shown only for illustrative purposes and is not part of the present invention.

[0050] The receptacle 5 formed by the housing 3 of the tube connector is delimited by an inner surface 19 and two open ends 21, 23. The first open end 21 is also referred to as an insertion end 21 through which and from which the tube 7 and all elements 9, 11, 13, 15, 17 can be inserted into the receptacle 5. The second end 23 is also referred to as an abutment end 23. The abutment end 23 comprises an opening through which a fluid of the pressurized fluid system can flow in and out of the tube connector 1.

[0051] The main sealing element 9 is an o-ring made from an elastic plastic material such as rubber and forms a passage 10 for receiving a tube 7. It is adapted to provide a tight sealing between the tube 7, and to be more precise an outer surface 24 of a tube 7, once it has been inserted into the tube connector 1 and an inner surface 19 of the housing 3 of the tube connector 1. The sealing provided by the main sealing element 9 is sufficiently tight to prevent fluid of the pressurized fluid system from evading the pressurized fluid system at the connection of the tube connector 1 and the tube 7.

[0052] Adjacent to the main sealing element 9 the gripping element 11 is arranged. The gripping element 11 is formed as an annual brass ring comprising a slit. The slit, which is not shown in the Figures, facilitates that a width of a passage 12 for the tube 7 formed by the gripping element 11 is variable. Hence, if a tube 7 is inserted into the receptacle 5 and, in particular, in the passage 12 formed by the gripping element 11, this passage 12 expands such that the tube 7 may be easily pushed into the tube connector 1. However, the gripping element 11 is formed from a resilient material such that it tries to return into its original shape and provides a tight grip around a tube 7 while the tube 7 is in place. In particular, as the tube 7 is usually made from a flexible plastic material, a gripping edge 25 of the gripping element 11 will at least slightly deform the tube 7 to provide a tighter grip.

[0053] The gripping element 11 provides an inclined surface 27 which is arranged such that the width of the passage 12 formed by the gripping element 11 increases from the abutment end 23 towards the insertion end 21. The inclined surface 27 facilitates an easier insertion of a tube 7 and prevents damages of an outer surface 24 of the tube 7 by the pointy or sharp gripping edge 25.

[0054] To prevent that a tube 7 that has been inserted into the tube connector 1 can be pulled out, the cone element 13 is provided in the receptacle 5. In the exemplary embodiment shown in FIG. 1 the cone element 13 is shown as a distinct or separate element. However, it is also conceivable that the cone element 13 is formed in one piece with the housing 3. The cone element 13 comprises an inclined surface 29 which is adapted for engagement with the gripping element 11. The inclined surface 29 is shaped such that a width of a passage for a tube 7 provided by the cone element 13 decreases from the abutment end 23 towards the insertion end 21. Thereby, if a load acts on the tube 7 such that the tube 7 is moved away from the abutment end 23 the gripping element 11 engages with the inclined surface 29 and the width of the passage 12 formed by the gripping element 11 is decreased more and more, the more load is applied. Thus, a self-tightening gripping mechanism is provided.

[0055] Further, the integrated release element 15 is also partially arranged in the receptacle 5. The integrated release element 15 comprises a tubular part 31, a top part 33 and an environmental sealing element 35 and also forms a passage 36 for receiving a tube 7. The tubular part 31 of the release element 15 extends between a tube 7 and the cone element 13. The tubular part 31 guides a tube 7 inserted into the tube connector 1. Thereby, insertion of a tube 7 is facilitated as the tube 7 cannot cant, twist or get stuck at an environmental seal as known from prior art tube connectors, the cone element 13 or even the gripping element 11. The tubular part 31 terminates towards the abutment end 23 in a release edge 37 which is adapted for pushing the gripping element 11 from a gripping to a non-gripping position if the release element 15 is moved towards the abutment end 23. In other words, the release edge 37 pushes the gripping element 11 towards the abutment end 23 and also radially away from a tube 7.

[0056] The top part 33 of the integrated release element 15 is formed as an actuating surface for pushing the integrated release element 15 towards the abutment end 23. Furthermore, the top part 33 is formed such that it limits the maximum distance the release element 15 can be pushed into the receptacle 5 as the top part 33 is adapted to engage with the housing 3.

[0057] The environmental sealing part or short environmental sealing 35 of the release element 15 seals the inner part of the housing 3, i.e. the receptacle 5, from the environment to prevent dirt from entering the interior of the tube connector 1. If dirt enters the interior of the housing 3, the sealing capacity of the main sealing element 9 may be reduced or it may not be possible to release the gripping element 11 anymore. Advantageously, the environmental sealing 35 is adapted to engage with a tube 7 if it is inserted into the tube connector 1 in such a manner that the gripping element 11 moves towards the abutment end 23 with the tube and pushes the gripping element 11 towards an open or non-gripping position such that the tube 7 can be inserted with little or preferably no contact to the gripping edge 25 of the gripping element 11. Thereby, damages to the tube 7 like scratches on its outer surface 24 created by the pointy gripping edge 25 are prevented.

[0058] Additionally, by engaging with the outer surface 24 of the tube 7 the environmental sealing element 35 also prevents unintended or accidental releases of the tube 7 from the tube connector 1. As the release element 15 moves within the boundaries defined by the gripping element 11 and stops described in detail in the following paragraphs, when the tube 7 is pulled away from the abutment end 23, the release element 15 also moves away from the abutment end 23. Hence, accidental engaging of the release edge 37 with the gripping element 11 which could cause an unintended release of the tube 7 is prevented.

[0059] The environmental sealing 35 is also adapted to engage with the housing 3. To provide a tight sealing the top part 33 of the release element 15 is formed in form of a collar 39 that extends at least partially between the cone element 13 and the housing 3. The collar 39 and the cone element 13 are formed such that a radial extension of a tube 7 caused by a pressure of a fluid inside the tube 7 is transferred through the cone element 13 and the collar 39 onto the environmental sealing 35 to improve a tightness of the environmental sealing 35. In other words, the cone element 13 and the collar 39 provide a load path onto the environmental sealing 35 towards the inner surface 19 of the housing 3. The environmental sealing 35 comprises a projection or protrusion 47 for sealing engagement with the inner surface 19. The protrusion 47 also facilitates a local and, thus, direct load transfer of radial forces created by a pressurized fluid in a tube 7 in the tube connector 1.

[0060] The top part 33 of the release element 15 comprises a first protrusion 41 adapted for engagement with a second protrusion 43 which is formed at the cone element 13. The protrusions 41, 43 are formed to provide a stop for the release element 15. By means of the protrusions 41, 43 the release element 15 cannot be pulled further away from the abutment end 23 than a predefined distance which is defined by the position of the protrusion 41, 43. Thus, the protrusions 41, 43 advantageously prevent that the release element 15 moves away from the rest of the tube connector 1. Furthermore, the protrusions 41, 43 provide an advantageous load path as described in the preceding paragraph for transferring radial loads of a tube 7 onto the environmental sealing 35.

[0061] The tube connector 1 shown in FIG. 1 further comprises a connecting end 51 with two sealing means 53 in the form of orings for providing a sealed connection of the tube connector 1 to another part of a pressurized fluid system.

[0062] FIGS. 2a, 2b, 2c and 2d show different detailed views of the integrated release element 15 of the exemplary embodiment of a tube connector 1 of FIG. 1. FIGS. 2a and 2b show the same sectional view of the release element 15, however, in FIG. 2b the environmental sealing element 35 has been omitted to show details of the further parts of the release element 15. Likewise, FIGS. 2c and 2d show the same top view of the integrated release element 15. In FIG. 2c the environmental sealing element 35 is in place, whereas in FIG. 2d it has been omitted.

[0063] As can be seen in FIG. 2a the environmental sealing element 35 is formed in one piece, i.e. the environmental sealing element 35 extends continuously from the passage 36 of the release element 15 through gaps 44 provided in the remainder of the release element 15 all the way to the protrusions 47 provided for engagement with the inner surface 19 of the housing 3 of the tube connector 1. As can be seen in FIGS. 2c and 2d four gaps 44 are provided that are evenly distributed in a circumferential direction and are arranged to form an “X”, a “+” or a cross. Between the channels or gaps 44 bridge parts 46 are provided connecting the top part 33 of the integrated release element 15 with the tubular part 31. As the gaps 44 are evenly distributed, so are the bridge parts 46.

[0064] Providing the evenly distributed gaps 44 in the other parts of the release element 15 advantageously allows producing the release element 15 in a two component or 2K injection molding process. In the injection molding process first the tubular part 31, the top part 35 and the collar 39 are molded from a second plastic material.

[0065] The second material is preferably a 30 vol. % glass fibre reinforced, heat stabilized polyamide 12. Such a material has the following mechanical properties:

TABLE-US-00001 Standard Unit State Tensile E- 1 mm/min ISO 527 MPa cond. 6000 Modulus Tensile 5 mm/min ISO 527 MPa cond. 105 strength at break Elongation 5 mm/min ISO 527 % cond. 8 at break Impact Charpy, 23° ISO kJ/m.sup.2 cond. 80 strength C. 179/1eU Impact Charpy, −30° ISO kJ/m.sup.2 cond. 80 strength C. 179/1eU Notched Charpy, 23° ISO kJ/m.sup.2 cond. 20 impact C. 179/1eA strength Notched Charpy, −30° ISO kJ/m.sup.2 cond. 15 impact C. 179/1eA strength Shore ISO 868 — cond. 77 hardness D

[0066] The abbreviation cond. stands for “conditioned”.

[0067] In a second step of the 2K injection molding process the environmental sealing element 35 is injected using a first plastic material. The first plastic material is a thermoplastic elastomer. By providing the four gaps 44 in an evenly distributed manner, injection molding the environmental sealing 35 from a thermoplastic elastomer is facilitated as the material can easily flow through the gaps 44 into a tool provided for molding the release element 15. For providing a permanent coupling between those parts of the release element 15 formed from the second plastic material and the environmental sealing element 35 a circumferential groove 48 is provided at the collar 39. Further, at the bridge parts 46 projections or rips 50 are molded which are also intended to improve a connection between the parts 31, 33, 35, 39, 46 of the release element 15 that are formed from different plastic materials.

[0068] A second embodiment of a tube connector 1 is shown in FIG. 3. Only those features of the tube connector 1 shown in FIG. 3 will be described in more detail that differ from the tube connector 1 shown in FIG. 1. Please note that in FIG. 3 a tube 7 is not shown.

[0069] The tube connector 1 shown in FIG. 3 differs from the tube connector 1 of FIG. 1 in specific details of the cone element and the environmental sealing 35. In particular, a third protrusion 45 is formed at the cone element 13. This third protrusion 45 is also adapted for engagement with the first protrusion 41 formed at the collar 39 of the release element 15. However, contrary to the second protrusion 43 the distance of the third protrusion 45 from the abutment end 23 is smaller. Thus, in an advantageous manner the cone element 13 provides two distances in which the integrated release element 15 is held in the receptacle 5. In normal operation the release element 15 is arranged such that the first protrusion 41 is always in between the abutment end 23 and the third protrusion 45. In case of excessive loads pulling a tube 7 out of the receptacle 5, the release element 15 moves past the third protrusion 45 and stops at the second protrusion 43. Once the excessive loads are not applied to the tube 7 anymore, it does not move in all the way past the third protrusion 45. The first protrusion 41 stays between the second and the third protrusion 43, 45. Thus, a person inspecting the tube connector 1 as shown in FIG. 3 can see that the release element 15 has been subject to high loads and may need maintenance.

[0070] Additionally, the embodiment of a tube connector 1 shown in FIG. 3 also has a slightly differently shaped environmental sealing 35 having two annularly closed projections or protrusions 47, 49 which engage with the inner surface 19 of the housing 3 to provide a better sealing of the receptacle 5 from the environment. The protrusions 47, 49 formed by the environmental sealing 35 are arranged such that in a normal operating position as shown in FIG. 3 they are arranged at the same distance from the abutment end 23 as the second and the third protrusion 43, 45. Thus, a direct load path is formed from a tube 7 through the cone element 13, the second and third protrusion 43, 45 and the protrusions 47, 49 formed by the environmental sealing element 35 to the housing 3 and a tight sealing is provided.

[0071] Finally, FIG. 4 shows a third exemplary embodiment of a tube connector 1 according to the present invention. With regard to FIG. 4 only the different embodiment of the environmental sealing element 35 will be described in more detail. The environmental sealing element 35 as shown in FIG. 4 is formed to provide a biasing means 55 for biasing the release element 15 away from the abutment end 23 of the tube connector 1. Thereby, unintended engagement of the release edge 37 of the integrated release element 15 with the gripping element 11 and, thus, unintended release of a tube 7 from the tube connector 1 can be prevented. For biasing the release element 15 away from the abutment end 23 the environmental sealing element 35 and, in particular, the biasing part 55 of the environmental sealing element 35 engages with the cone element 13. If the release element 35 is moved or pushed towards the abutment end 23, the biasing part 55 of the environmental sealing element is compressed. However, as the environmental sealing element 35 and also the biasing part 55 are made from an elastic or resilient material, the environmental sealing element 35 will resume its previous form as soon as no further pressure is applied to the release element 15. Thus, the biasing part 55 will push the release element 15 away from the abutment end and advantageously prevents unintended engagement of the release edge 37 with the gripping element 11.