Screw connection device for fluid lines, in particular for motor vehicle fluid lines

Abstract

A screw connection device for fluid lines having a coupling nut with an interior space and having an internal threading running over the circumference of the interior space, as well as having a connecting element with an external threading. A line end of a fluid line is accommodated in the coupling nut, wherein the line end exhibits an end shape. When the internal threading of the coupling nut is screwed to the external threading of the connecting element, a locating surface disposed in the interior space of the coupling nut is moved toward the back end of the end shape, or vice versa, respectively. A spring element is disposed between the locating surface and the back end of the end shape, running over the circumference of the fluid line.

Claims

1. A screw connection device for fluid lines, extending along a longitudinal axis (L) having a coupling nut with an internal wall having a thread thereon, said screw connection device having a connecting element with a mating external thread thereon, wherein the coupling nut is accommodated on a line end of a fluid line and, wherein the line end includes an end shape at a front end thereof, comprising a line flange, including a back end, wherein the line flange is a flaring of the fluid line, wherein, a conical locating surface of the coupling nut is disposed in the interior space of the coupling nut and is movable toward the back end of said line flange of said fluid line, and wherein a spring element is disposed on said fluid line between the conical locating surface of said coupling nut and the back end of said line flange, wherein the spring element is a single piece and comprises a stop section and a connecting section following each other in an axial direction, said stop section having a locating surface contacting said back end of said line flange and a locating surface contacting said conical locating surface of said coupling nut, said stop section being compressed between said back end of said line flange and said conical locating surface of said coupling nut, wherein both locating surfaces of the stop section are shaped conically, wherein the connecting section has an inner cylindrical surface and an outer cylindrical surface, wherein the spring element comprises a first end that belongs to the stop section and a second outermost axial end that belongs to the connecting section and wherein the second outermost axial end is substantially perpendicular with the inner and outer cylindrical surfaces of the connecting section, wherein the second outermost axial end of the spring element is completely contained within and directly abuts the coupling nut in an axial direction in a screwed-together state.

2. The screw connection device according to claim 1, wherein the connecting element is a connecting line.

3. The screw connection device according to claim 1, wherein the end shape of the line end rests with a connecting surface against a complementary connecting surface of the connecting element when the screw connection device is in the screwed together state.

4. The screw connection device according to claim 1, wherein the conical locating surface of the coupling nut comes in contact with the spring element during movement of said conical locating surface of said coupling nut toward the back end of said line flange, and the spring element comes in contact with the back end of the end shape, such that the spring element is clamped, respectively, in the space between the conical locating surface and the back end of the end shape.

5. The screw connection device according to claim 4, wherein the spring element is deformed in the course of said movement.

6. The screw connection device according to claim 1, wherein the spring element consists of metal.

7. The screw connection device according to claim 1, wherein the conical locating surface of the coupling nut is disposed at an angle to the longitudinal axis (L) of the fluid line, and wherein the conical locating surface of the coupling nut forms an angle () with the longitudinal axis (L) of the fluid line of 10-170.

8. The screw connection device according to claim 7, wherein the locating surface of the spring element contacting the conical locating surface of the coupling nut is disposed at an angle to the longitudinal axis (L) of the fluid line, and wherein, said locating surface of the spring element contacting the conical locating surface of the coupling nut forms an angle (.sub.1) with the longitudinal axis (L) of the fluid line of 10-170.

9. The screw connection device according to claim 8, wherein the locating surface of the spring element contacting said back end of said line flange is disposed at an angle to the longitudinal axis (L) of the fluid line, and wherein, said locating surface of the spring element contacting said back end of said line flange forms an angle (.sub.2) with the longitudinal axis (L) of the fluid line of 10-170.

10. The screw connection device according to claim 9, wherein the end shape of the fluid line at the back end of the line flange is disposed at an angle to the longitudinal axis (L) of the fluid line, and forms an angle (.sub.3) with the longitudinal axis (L) of the fluid line of 10-170.

11. The screw connection device according to claim 1, wherein the conical locating surface of the coupling nut is a component of a stop shoulder of the coupling nut, and wherein a connecting surface angled away from the conical locating surface is connected to the conical locating surface, and wherein the connecting surface is disposed parallel to the longitudinal axis (L) of the fluid line.

12. The screw connection device according to claim 1, wherein the fluid line passes through a center hole of the coupling nut, and wherein the conincal locating surface of the coupling nut abuts, or is connected to, the center hole.

13. The screw connection device according to claim 1, wherein the locating surface of the spring element contacting said back end of said line flange is provided with a coating having a friction coefficient () which prevents occurrence of disadvantageous torsional forces.

14. A screw connection device for fluid lines, extending along a longitudinal axis (L), the screw connection device comprising: a coupling nut with an internal wall having a thread thereon, a connecting element with a mating external thread thereon, a line end of a fluid line, wherein the coupling nut is accommodated on the line end, an end shape of the line end disposed at a front end of the line end, the end shape comprising a line flange including a back end, wherein the line flange is a flaring of the fluid line, a conical nut locating surface of the coupling nut, wherein the conincal nut locating surface of the coupling nut is disposed in the interior space of the coupling nut and is movable toward the back end of the line flange of the end shape of the fluid line, a spring element disposed on the fluid line between the concial nut locating surface of the coupling nut and the back end of the line flange, wherein the spring element includes a first spring locating surface contacting the back end of the line flange and a second spring locating surface contacting the conical nut locating surface of the coupling nut, wherein the spring element is compressed between the back end of the line flange and the conincal nut locating surface of said coupling nut, wherein the spring element is a single-piece and includes a stop section and a connecting section following each other in an axial direction, the connecting section angled away from the stop section, the stop section includes the second spring locating surface that contacts the conical nut locating surface and the first spring locating surface that contacts the back end of the line flange of the end shape, wherein the first and second spring locating surfaces are shaped conically, and wherein the connecting section is disposed parallel to the longitudinal axis (L) of the fluid line and the connecting section includes an inner cylindrical surface and an outer cylindrical surface, and the stop section is disposed at an angle transverse to the longitudinal axis (L), wherein the spring element comprises a first end that belongs to the stop section and a second outermost axial end that belongs to the connecting section and wherein the second outermost axial end is substantially perpendicular with the inner and outer cylindrical surfaces of the connecting section, wherein the second outermost axial end of the spring element is completely contained within and directly abuts the coupling nut in an axial direction in a screwed-together state.

15. The screw connection device according to claim 14, wherein the coupling nut defines a connecting surface angled away from the conical nut locating surface of the coupling nut and is connected to the conical nut locating surface, wherein the connecting surface is disposed parallel to the longitudinal axis (L) of the fluid line, the connecting section of the spring element is disposed radially between the fluid line and the connecting surface of the coupling nut and contacts the fluid line and the connecting surface of the coupling nut, and the stop section of the spring element is disposed between the conincal nut locating surface of the coupling nut and the back end of the line flange and contacts the conical nut locating surface of the coupling nut and the back end of the line flange.

Description

DESCRIPTION OF THE DRAWINGS

(1) In the following the invention shall be explained in greater detail based on drawings which depict a single embodiment example. They show, in a schematic depiction:

(2) FIG. 1 a cutaway through a first embodiment of the screw connection according to the invention in the not yet screwed together state,

(3) FIG. 2 the subject matter according to FIG. 1 in a partially screwed together state,

(4) FIG. 3 the subject matter according to FIG. 1 in a fully screwed together state,

(5) FIG. 4 the subject matter according to FIG. 1 in a second embodiment,

(6) FIG. 5 the subject matter according to FIG. 2 in a second embodiment, and

(7) FIG. 6 the subject matter according to FIG. 3 in a second embodiment of the invention.

(8) FIG. 7 shows a portion of the subject matter of FIG. 3 on an enlarged scale.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

(9) The figures show a screw connection device according to the invention, for fluid lines 1, in particular for motor vehicle fluid lines. The screw connection device has a coupling nut 2 with an interior space 3 and an internal threading 4 running over the circumference of the interior space 3. Moreover, the screw connection device exhibits a connecting element, which is designed as a connecting line 5 in the embodiment example, and is equipped with an external threading 6. In the screwed together state of the screw connection device (FIGS. 3 and 6), the external threading 6 engages with the internal threading 4 of the coupling nut 2.

(10) A line end 7 of the fluid line 1 is accommodated in the coupling nut 2, or in the interior space 3 of the coupling nut 2, respectively, and said line end 7 exhibits a front end flange 8 (line flange). When screwing the internal threading 4 of the coupling nut 2 to the external threading 6 of the connecting element, or the connecting line 5, respectively, a back end locating surface 9 disposed in the interior space 3 of the coupling nut 2 is moved toward the back end 10 of the flange 8, or, conversely, the back end 10 of the flange is moved toward the locating surface 9 of the coupling nut, respectively (FIGS. 2 and 5). According to the invention, a spring element 11 is disposed between the locating surface 9 of the coupling nut 2 and the back end 10 of the flange 8, which runs over the circumference of the fluid line 1. For practical purposes and in the embodiment example (FIGS. 1 and 4), the spring element 11 is disposed on the fluid line 1, or is slid onto the fluid line 1, respectively, when the screw connection device is not yet screwed together.

(11) In the course of the screwing the screw connection device together, the locating surface 9 of the coupling nut 2 comes in contact with the spring element 11, or the spring element 11 comes in contact with the back end 10 of the flange, such that the spring element 11 is basically clamped in the space between the locating surface 9 and the back end 10 of the flange. Preferably, and in the embodiment example, the spring element is compressed thereby. In the framework of the invention, the spring element 11 consists of a metal, and preferably consists of steel.

(12) In the screwed together state of the screw connection device, the flange 8 of the line end 7 rests with a connecting surface 12 in a sealing manner, for practical purposes, against a complementary connecting surface 13 of the connecting line 5. Preferably, and in the embodiment example, the locating surface 9 of the coupling nut 2, when in the screwed together state of the screw connection device, forms an angle with the longitudinal axis L of the fluid line 1 of 35-45, and in particular, an angle of a of approx. 40. For practical purposes, the locating surface 14 of the spring element 11 at the coupling nut end is disposed at an angle to the longitudinal axis L of the fluid line 1, and it is recommended that the locating surface 14 at the coupling nut end also forms an angle .sub.1 with the longitudinal axis L of the fluid line 1, when in the screwed together state of the screw connection device, of 35-45, and in particular, an angle .sub.1 of 40. It is recommended that the locating surface 15 of the spring element 11 at the flange end is also disposed at an angle to the longitudinal axis L of the fluid line 1, and that this locating surface 15 at the flange end forms an angle .sub.2 of 35-45, and in particular an angle .sub.2 of approx. 40 with the longitudinal axis L of the fluid line 1, when the screw connection device is in the screwed together state. Moreover, it is preferred that the back end 10 of the flange 8 on the fluid line 1 is disposed at an angle in relation to the longitudinal axis L of the fluid line 1, and that the back end 10 of the flange forms an angle .sub.3 of 35-45, and preferably approx. 40, with the longitudinal axis L of the fluid line 1.

(13) FIGS. 1-3 show a first embodiment of the screw connection device according to the invention. In this embodiment, the locating surface 9 of the coupling nut 2 is a component of a stop shoulder 16 of the coupling nut 2, and the locating surface 9 is connected in this case to the connecting surface 17 that is angled away from the locating surface 9. Preferably, and in the embodiment example, the connecting surface 17 is disposed parallel to the longitudinal axis L of the fluid line 1. It is recommended, and is the case in the embodiment example, that the locating surface 9 and the connecting surface 17 form an angle .sub.4 of preferably 35-45, and in particular 40. In this embodiment the spring element 11 has a stop section 18 for practical purposes, on which the locating surface 14 for the coupling nut and the locating surface 15 for the flange are provided. Moreover, the spring element 11 exhibits a connecting section 19, angled away from the stop section 18, which is preferably, and in the embodiment example, disposed parallel to the longitudinal axis L of the fluid line 1. The stop section 18 of the spring element 11 forms an angle .sub.5 with the connection section 19 here of preferably 35-45, and in particular 40. The connecting section 19 rests at one end against the connecting surface 17 of the stop shoulder 16, and at the other end on the fluid line 1. It can be derived from FIGS. 1-3 that the stop shoulder 16 is connected directly to a center hole 20 in the coupling nut 2, through which the fluid line 1 passes.

(14) FIGS. 4-6 show a second preferred embodiment of the screw connection device according to the invention. In this case, the spring 11a is shorter than in the embodiment example according to FIGS. 1-3, and the spring element 11a is only disposed between the locating surface 9 of the coupling nut 2 and the back end 10 of the flange 8. The spring element 11a corresponds here, basically, only to the stop section 18 of the first embodiment of the invention explained above, and includes locating surfaces 14a and 15a. For practical purposes, and in the embodiment example, the locating surface 9 is connected directly to the center hole 20 of the coupling nut 2, through which the fluid line 1 passes in this embodiment.

(15) It is indicated in FIG. 7 that at least the locating surface 15 of the spring element 11 at the flange end is provided with a coating 21 having a low friction coefficient . By this means, the occurrence of disadvantageous torsional forces can be prevented, and the unintentional releasing of the screw connection can be counteracted.

(16) Variations and modifications of the foregoing are within the scope of the present invention. It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.