Coupling part for a hose coupling

Abstract

The invention relates to a coupling part (1) for a hose coupling, in particular for high-pressure hydraulic lines, having a connection head (2) for connection to a fitting and an extruded joint (3) shaped on the connection head for receiving a hose end section (6), which is pushed onto, can be fixed sealingly by compression on the extruded joint by means of an at least partially sleeve-shaped extruded frame (5) surrounding the hose end section, and having a ribbed profile comprising ribs defined by grooves, wherein the ribbed profile has at least two profile sections (32, 33), wherein the grooves (323) of a first profile section (32) facing the connection head (2) have a symmetrical cross section and the grooves (332) of the second profile section (33) have an asymmetrical cross section, and wherein the grooves (332) of the second profile section (33) have a greater groove volume relative to the grooves (323) of the first profile section (32). The invention also relates to a hose coupling having such a coupling part (1).

Description

TECHNICAL FIELD

[0001] The invention relates to a coupling part for a hose coupling, in particular for a high-pressure hydraulic line, according to the invention. The invention also relates to a hose coupling according to the invention. BACKGROUND

[0002] A coupling element for a high-pressure hydraulic line is known from the German utility model DE 20 2004 008 126 U1. The coupling element comprises a tubular connecting piece with a hose nipple and means for coupling to a fitting. A hose retaining device in the form of a ribbed profile is provided on the hose nipple. The high-pressure hoses used are usually multilayered and contain a metal insert, which is necessary for high-pressure applications, in a known manner. For assembly, the hose nipple of the coupling element is pushed into the inner hose of the high-pressure hose to be fixed. The ribbed profile then prevents the hose from being easily pulled out. At the same time as the high-pressure hydraulic hose, an extruded frame, which is located on the hose end, is pushed onto the hose nipple. In order to fix the high-pressure hydraulic hose to the coupling element, the extruded frame is pressed onto the coupling element by radial compression. During the extrusion process, tensile loads of the inner hose relative to the hose body can occur, which can lead to micro-cracks in the inner hose, whereby the tightness of the connection to the high-pressure line is no longer guaranteed. SUMMARY

[0003] The invention wishes to provide a remedy here. The object of the invention is to provide a coupling part for a hose coupling in which the risk of micro-cracks in the inner hose when compressing an extruded frame arranged outside the hose end is avoided. According to the invention, the object is achieved by a coupling part having the features of the invention.

[0004] With the invention, a coupling part for a hose coupling is provided in which the risk of micro-cracks in the inner hose when compressing an extruded frame arranged outside the hose end is avoided. Since the ribbed profile has at least two profile sections, wherein the grooves of the first profile section facing the connection head have a symmetrical cross-section and the grooves of the second profile section arranged adjacent to the first profile section have an asymmetrical cross-section, the grooves of the second profile section have a larger groove volume relative to the grooves of the first profile section, the required accommodation volume of the grooves is created depending on the axial forces acting on the inner hose and the resulting material movement.

[0005] In a refinement of the application, the recess of the second profile section has a greater recess volume than the recess of the first profile section. Here, the load on the inner hose is further reduced when the pressing frame is compressed. It has been shown that the required material accommodation volume of the recess decreases in the direction of the connection head. By virtue of the asymmetrically configured profile sections, not only is sufficient accommodation volume for the inner hose material achieved during the pressing process, but also the required pull-out inhibition, with a small resistance for the pushing of the hose section onto the pressing joint.

[0006] In a design of the application, a cylindrical section is arranged between the first profile section and the second profile section, which transitions into a symmetrical recess on its side facing the first profile section and into an asymmetrical recess on its side facing the second profile section. Good guidance of the hose section to be pushed on is thereby achieved. Furthermore, good axial fixing of the compressed pressing frame is achieved by the cylindrical section, which forms an undercut around the cylindrical section.

[0007] In a further design of the application, the asymmetrical recess has a slot-shaped cross section with a flat recess bottom, which is defined by two recess walls that are angled with different inclinations, wherein the entry wall facing the connection head has a smaller inclination than the sealing wall facing away from the connection head. The inflow of the pressed inner hose volume is thereby facilitated, whereby material stress is reduced. The material is guided over the entry wall onto the sealing wall, where it is accumulated, whereby a good sealing effect and a good pull-out inhibition are produced.

[0008] In a further design of the application, the entry wall encloses an angle a with the recess bottom of greater than or equal to 155 degrees and less than or equal to 165 degrees, preferably 160 degrees. It has been shown that particularly small material stress of the hose inner sleeve is thereby achieved. Preferably, the sealing wall encloses an angle β with the recess bottom of greater than or equal to 115 degrees and less than or equal to 125 degrees, preferably 120 degrees.

[0009] In a refinement of the application, the pressing joint has a through section on its end facing away from the connection head, which is composed of a cylindrical sub-section, which transitions into a conical end section. The pushing on of the hose section is thereby simplified. Preferably, the cylindrical sub-section is defined by the sealing wall of the asymmetrical recess.

[0010] In a design of the application, the second profile section has at least two, preferably at least three, particularly preferably at least four asymmetrical recesses. Thereby, sufficient accommodation volume is provided for the inner hose material when the pressing frame is compressed, whereby material stress is minimized and at the same time the sealing action is maximized.

[0011] In another design of the application, at least one of the asymmetrical grooves has a smaller groove volume than the other asymmetrical groove adjacent in the direction of the through section, wherein preferably the smaller the spacing of all asymmetrical grooves of the second profile section relative to the through section, the larger the groove volume thereof has. Thereby a sufficient material accommodation corresponding to the material extrusion of the hose inner shell upon compression is provided.

[0012] In a refinement of the application, the first profile section has at least two ribs, wherein a first rib viewed from the connecting head has an increased outer diameter relative to the remaining peripheral surface of the compression joint, and wherein the peripheral surface of the first rib preferably has an arcuate, in particular circular arcuate, cross section. Here, a good fixation of the pushed-through hose section is achieved, which, due to the circular arcuate cross section of the first rib, can be well moved through the first rib despite the larger diameter thereof.

[0013] In a design of the application, a cylindrical holding piece is arranged between the connecting head and the compression joint, on which at least a partially encircling holding tab is shaped, the outer diameter of which is larger than the largest diameter of the compression joint. Thereby a reliable connection to the compression frame is achieved.

[0014] Furthermore, the subject matter of the application is a hose coupling having such a coupling part and an at least partially sleeve-shaped compression frame, which can be fitted onto a hose section pushed onto the compression joint of the coupling part and can be compressed for fixation with the compression joint by a radially acting pressure, wherein the compression frame is provided on its inner peripheral surface with a claw profile, which consists of a radially inwardly pointing encircling claw rib having a substantially triangular cross section for penetrating into the outer peripheral surface of the hose section during compression, and wherein the claw profile preferably has a zigzag cross section.

[0015] In a refinement of the application, the compression frame has a holding groove upstream of the claw profile, into which the holding tab arranged on the coupling part between the connecting head and the compression joint engages after the compression frame is compressed onto the compression joint.

[0016] Further refinements and designs of the application are given in the present disclosure. Embodiments of the application are shown in the drawings and are described in detail below. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A schematic view of the coupling part is shown:

[0018] a) in a spatial view;

[0019] b) in a partial longitudinal section;

[0020] c) in a plan view,

[0021] Figure 2 in a partial longitudinal section Figure 1 schematic view of the extrusion joint of the coupling part

[0022] Figure 3 detail view of the first profile section "A" Figure 2

[0023] Figure 4 detail view of the second profile section "B" Figure 2

[0024] Figure 5 diagrammatic illustration of a hose coupling with a hose fitted by means of an extrusion frame

[0025] Figure 6 detail view of the hose behavior during the pressing of the extrusion frame in four successive extrusion states DETAILED DESCRIPTION

[0026] The coupling part 1 selected as an example comprises a connecting head 2 on which an extrusion means 3 is formed. The coupling part 1 is provided with a through-hole 11 along its longitudinal center axis.

[0027] The connecting head 2 has a conically widened plug part 21 which is provided with a recess 211 for accommodating a sealing ring 22. A diametrically widened collar 23 is coupled to the plug part 21, by means of which a stop 231 is formed. The collar 23 is provided on its side opposite the stop 231 with a bevel 24 to which a cylindrical section 25 is coupled. The cylindrical section 25 is provided with a recess 251 for accommodating a snap ring 26. The connecting head 2 accommodates a locking nut 4 which rests against the bevel 24 and is held axially captive by means of the snap ring 26.

[0028] The extrusion joint 3 is formed essentially by a retaining section 31 to which a first profile section 32 and a second profile section 33 are coupled, between which a cylindrical section 34 is arranged. On the end side, a through section 35 is coupled to the second profile section 33.

[0029] ​​The holding section 31 is essentially cylindrically configured and has a circumferential holding flange 311 essentially in the center, which together with the cylindrical section 25 of the connection head 2 defines a holding groove 312. Coupled to the holding section 31 is a first profile section 32, which in the embodiment has two ribs 321, 322 arranged parallel to one another, which are defined by three symmetrical grooves 323. The grooves 323 have an isosceles trapezoidal cross section. The first rib 321, viewed from the connection head 2, has an increased outer diameter relative to the second rib 322. The peripheral surface of the first rib 321 here has a circular-arc cross section.

[0030] In the embodiment, the second profile section 33 comprises three ribs 331 arranged parallel to one another, which are respectively defined by asymmetrical grooves 332. The asymmetrical grooves 332 have a slot-shaped cross section with a flat groove bottom, which is defined by two angularly arranged groove walls of different inclination. The groove wall facing the connection head 2 forms an entry wall 333 and has a smaller inclination than the groove wall facing away from the connection head 2, which forms a sealing wall 334. In the embodiment, the entry wall encloses an angle of 160° with the groove bottom and the sealing wall encloses an angle of 120° with the groove bottom. The grooves 332 are dimensioned such that they have a larger groove volume than the symmetrical grooves 323 of the first profile section 32.

[0031] Here, the asymmetrical grooves 332 are dimensioned relative to one another such that the smaller the spacing thereof relative to the through section 35, the larger the groove volume thereof, respectively.

[0032] The through section 35 is essentially cylindrically configured and has a cylindrical section 352, which transitions into a conically tapering end section 351.

[0033] In Figure 5 a hose coupling with such a coupling part 1 before the compression of the extrusion frame is shown. Here, the hose section 6 is pushed onto the extrusion head 3 of the coupling part 1 until it rests against the holding section 31. Here, the upper rubber 61 of the hose section 6 is stripped onto the wire mesh 62 in the region of the extrusion frame 5. Here, the wire mesh 62 cannot be damaged, since it imparts pressure resistance to the inner hose 63. The diameter of the hose section 6 is chosen such that it is smaller than or identical to the inner diameter of the extrusion frame 5, onto which the extrusion frame with its claw profile 51 is slipped over the hose section 6. The extrusion frame 5 has a holding groove 52 upstream of the claw profile 51, into which the holding flange 311 of the extrusion head 3 engages after the extrusion frame has been compressed.

[0034] The extrusion frame 5 is essentially hollow-cylindrical and has a claw profile 51 on its inner side. Upstream of the claw profile there is arranged a retaining groove 52 which is delimited by an end-side head disc 53 which is provided with a bore. The outer contour of the extrusion frame 5 can be configured differently depending on the respective field of application of the hose coupling. Thus, the outer contour of the extrusion frame can have, for example, a circular or polygonal cross section. The wall thickness of the extrusion frame is chosen such that it can withstand forces acting radially outwards by the fluid flowing in the hose section 6.

[0035] In order to fit the hose coupling preventively to the hose section 6, a radially acting pressure is applied from the outside to the extrusion frame 5. The external pressure causes a compression of the extrusion frame 5, whereby the claws of the claw profile 51 are pressed into the wire mesh 62 of the hose section 6 and cause a fixed connection between the coupling part 1 and the hose section 6. Furthermore, the extrusion frame 5 is pressed down such that the retaining groove 52 of the extrusion frame 5 surrounds the retaining flange 311 of the spigot extrusion joint 3, whereby the extrusion frame 5 is connected form-fittingly with the extrusion joint 3. The bore of the head disc 53 here rests against the retaining groove 312 of the retaining section 31 of the extrusion joint 3.

[0036] In Figure 6 different extrusion states of the hose coupling during the pressing of the extrusion frame are shown in longitudinal sectional views. Here, the behaviour of the inner hose 63 of the hose section 6 during the extrusion process is well visible. With increasing pressing of the extrusion frame 5, the axial movement or elongation of the inner hose 63 relative to the wire mesh 62 can be seen. The inner hose material pressed down can thus almost without resistance enter into the asymmetric recess 332 through the entry wall 333 of the asymmetric recess 323 of the second profile section 33 until it is stopped against the sealing wall 334 of the asymmetric recess 332, whereby a high sealing effect is achieved with minimal stress of the inner hose material. Here, the inner hose 63 seals and remains in the symmetric recess 323 of the first profile section 32 in the region of the first profile section in which almost no axial movement of the inner hose material occurs. Furthermore, the force- form closure between the extrusion frame 5 and the retaining section 31 of the coupling part 1 achieved by the pressing is clearly visible, wherein the retaining groove 52 of the extrusion frame 5 is pressed around the retaining flange 311 of the retaining section 31.

[0037] The coupling part according to the application is suitable for various hoses. Depending on the outer diameter of the hose section to be accommodated, a corresponding extrusion frame 5 is chosen, with which the hose section 6 is then pressed to the coupling part 1.

Claims

1. Coupling part (1) for a hose coupling, which coupling part has a connection head (2) for connection with a fitting and a press joint (3) shaped on the connection head for receiving a hose section (6), which pushed-through hose section (6) can be fixed sealingly by compression on the press joint by means of an at least partially sleeve-shaped press frame (5) surrounding the hose section, and the press joint has a ribbed profile, which ribbed profile comprises ribs defined by grooves, characterized in that, The profiled section has at least two profile sections (32, 33), wherein the groove (323) of a first profile section (32) facing the connection head (2) has a symmetrical cross section and the groove (332) of a second profile section (33) has an asymmetrical cross section, and wherein the groove (332) of the second profile section (33) has a larger groove volume relative to the groove (323) of the first profile section (32), wherein the second profile section (33) has at least two asymmetrical grooves (332), and wherein at least one of the asymmetrical grooves (332) has a smaller groove volume than the other asymmetrical groove (332) adjacent in the direction toward the end of the extruded joint (3) opposite the connection head (2).

2. The coupling member of claim 1, wherein The coupling part (1) is provided for a high-pressure hydraulic line.

3. The coupling member of claim 1, wherein Between the first profile section (32) and the second profile section (33) a cylindrical section (34) is arranged, which transitions into a symmetrical groove (323) on its side facing the first profile section (32) and into an asymmetrical groove (332) on its side facing the second profile section (33).

4. The coupling member according to any one of claims 1 to 3, characterized in that, The asymmetrical groove (332) has a trough-shaped cross section with a flat groove bottom, which is defined by two differently beveled, angularly arranged groove walls (333, 334), wherein the entry wall (333) facing the connection head has a smaller bevel than the sealing wall (334) facing away from the connection head (2).

5. The coupling member of claim 4, wherein, The entry wall (333) encloses with the groove bottom an angle a of greater than or equal to 155 degrees and less than or equal to 165 degrees.

6. The coupling member of claim 5, wherein, The entry wall (333) encloses with the groove bottom an angle a of 160 degrees.

7. The coupling member of claim 4, wherein, The sealing wall (334) encloses with the groove bottom an angle β of greater than or equal to 115 degrees and less than or equal to 125 degrees.

8. The coupling member of claim 7, wherein, The sealing wall (334) encloses with the groove bottom an angle β of 120 degrees.

9. The coupling member of any one of claims 1 to 3, wherein, The extruded joint (3) has on its end opposite the connection head (2) a through section (35), which is composed of a cylindrical subsection (352), which transitions into a conical end section (351).

10. The coupling member of claim 9, wherein, The cylindrical subsection (352) is defined by the sealing wall (334) of the asymmetrical groove (332).

11. The coupling member of any one of claims 1 to 3, wherein, The second profile section (33) has at least three asymmetrical grooves (332).

12. The coupling member of claim 11, wherein, The second profile section (33) has at least four asymmetrical grooves (332).

13. The coupling member of claim 11, wherein, The extruded joint (3) has on its end opposite the connection head (2) a through section (35), wherein the smaller the distance of all asymmetrical grooves (332) of the second profile section (33) from the through section (35) the larger the groove volume.

14. The coupling member of any one of claims 1 to 3, wherein, The first profile section (32) has at least two ribs (321, 322), wherein a first rib (331) viewed from the connecting head (2) has an increased outer diameter relative to the remaining peripheral surface of the extrusion head, and wherein the peripheral surface of the first rib (331) has an arc-shaped cross section.

15. The coupling member of claim 14, wherein, The peripheral surface of the first rib (331) has a circular-arc-shaped cross section.

16. The coupling member of any one of claims 1 to 3, wherein, Between the connecting head (2) and the extrusion head (3) a cylindrical holding section (31) is arranged, on which at least a partially circumferential holding flange (311) is formed, which has an outer diameter which is greater than the greatest diameter of the extrusion head (3).

17. A hose coupling comprising a coupling part (1) according to any one of claims 1 to 16 and an at least partially sleeve-shaped extrusion frame (5) which can be fitted onto a hose section (6) which is pushed onto the extrusion joint (3) of the coupling part (1) and can be compressed by a radially acting pressure for securing with the extrusion joint (3), wherein The extrusion frame (5) is provided on its inner peripheral surface with a claw profile (51), which consists of a circumferential claw rib which points radially inwards, which has a substantially triangular cross section for penetrating into the outer peripheral surface of the hose section (6) during the pressing, and wherein the claw profile (51) has a zigzag-shaped cross section.

18. The hose coupling according to claim 17, characterized in that The extrusion frame (5) has a holding recess (52) upstream of the claw profile (51), into which the holding flange (311) arranged on the coupling part (1) between the connecting head (2) and the extrusion head (3) engages after the pressing of the extrusion frame (5) onto the extrusion head (3).

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