Method for connecting a cable to a connector

Abstract

Method for connecting a line (12) to a connector (10) of a hydraulic coupling system, wherein the method comprises the following process steps: a) Providing a connector (10) with a stepped through-hole (14) such that the through-hole (14) has at least a first diameter (16) and a second diameter (18), wherein the first diameter (16) is smaller than the second diameter (18); b) Providing a conduit (12) with an outer diameter that is larger than the first diameter (16) of the through-hole (14) and smaller than or equal to the second diameter (18) of the through-hole (14) at least at a connection area (36); c) Inserting a fixing agent (26) into the through-hole (14), wherein the fixing agent (14) serves to temporarily fix the conduit (12); d) Inserting the line (12) with the connection area (36) into the through hole (14) of the connector (10) while fixing the line (12) to the fixing means (26); e) Performing a rotating relative motion between the line (12) and the connector (10); wherein f) the connection area (36) of the conduit (12) is relocated into the area of ​​the first diameter (16) of the through-bore (14); and g) Removal of the fixing element (26) from the conduit (12), wherein the fixing element (26) is designed as a cylindrical mandrel with a stepped outer wall (28) such that the fixing element (26) has a fixing area (30) for fixing the conduit (12) and a guiding area (32) for guiding the fixing element (26) in the through-hole (14).

Description

[0001] The present invention relates to a method for connecting a line to a connector. In particular, the present invention relates to a method by which a line, such as in particular a plastic line, can be easily connected to a connector, which can also be molded from a plastic. The present invention further relates to a method for assembling a hydraulic system comprising the above-described method.

[0002] Hydraulic clutch systems are known to have a clutch master cylinder controlled by a piston rod, which pumps hydraulic fluid from a reservoir to a clutch slave cylinder, or vice versa, from the clutch slave cylinder to the reservoir. Hydraulic lines are usually provided between the clutch slave cylinder and the clutch master cylinder, and between the clutch master cylinder and the clutch slave cylinder to pump hydraulic fluid. Furthermore, the piston rod is usually actuated by the driver of a vehicle using a clutch pedal. In this way, a clutch can be opened and closed again.

[0003] Various of the aforementioned hydraulic functional elements are often connected to one another by means of connections, such as connectors to which the hydraulic lines are connected, in order to enable simple and multifunctional connection or assembly.

[0004] For example, document DE 10 2010 022 506 A1 describes connecting a plastic line to a connector using friction welding. Both the plastic line and the connector are designed in a stepped manner to ensure a precise fit of the plastic line in the connector. According to this document, the connector is further provided with radial holes in the connection area through which material can escape from the connection area.

[0005] However, the solutions known from the prior art may still offer further potential for improvement, particularly with regard to cost-effective and process-efficient connection of a line in a connector. US Pat. No. 4,547,239 A discloses a method for attaching a fitting to a line.

[0006] Further prior art is known from US 3 917 497 A, DE 199 27 431 A1, WO 2007 / 137 553 A2, DE 849 481 B and DE 690 21 955 T2.

[0007] It is therefore the object of the present invention to at least partially overcome the disadvantages known from the prior art. In particular, the object of the present invention is to provide a solution by which a line can be connected to a connector in a cost-effective and process-efficient manner.

[0008] The object is achieved according to the invention by a method for connecting a line to a connector having the features of claim 1. The object is further achieved according to the invention by a method for assembling a hydraulic system having the features of claim 9 and by a use according to claim 10. Preferred embodiments of the invention are described in the subclaims, in the description or the figures, wherein further features described or shown in the subclaims or in the description or the figures can represent an object of the invention individually or in any combination, unless the context clearly indicates the opposite.

[0009] A method is proposed for connecting a line to a connector, in particular a hydraulic coupling system, the method comprising the following method steps: a) providing a connector having a stepped through-bore such that the through-bore has at least a first and a second diameter, the first diameter being smaller than the second diameter; b) providing a line having an outer diameter which, at least at a connecting region, is greater than the first diameter of the through-bore and less than or equal to the second diameter of the through-bore; c) introducing a fixing means into the through-hole, the fixing means serving to temporarily fix the line; d) inserting the cable with the connection area into the through-hole of the connector while fixing the cable to the fixing means; e) performing a rotating relative movement between the cable and the connector; wherein f) the connection area of ​​the line is shifted to the area of ​​the first diameter of the through-bore; and g) Removing the fixing agent from the line.

[0010] By means of a method described above, it is possible in a particularly simple manner to connect the latter to one another, in particular to form a hydraulic coupling system, without sometimes complex pretreatment steps or without the presence of specially shaped lines and / or connectors.

[0011] For this purpose, the method comprises at least the following method steps, which can be carried out in the order described above or in an at least partially different order, without departing from the scope of the invention.

[0012] According to method step a), the method described here comprises providing a connector with a stepped through-bore. The through-bore is a fluid guide that runs completely through the connector to allow passage for hydraulic fluid. Due to its stepped configuration, the through-bore has at least a first and a second diameter, with the first diameter being smaller than the second diameter. In particular, it can be provided that the connector is a male connector and that the first diameter, i.e. the smaller diameter in the insertion direction of the connector, is present compared to the second, or larger, diameter.

[0013] Furthermore, according to method step b), a line is provided with an outer diameter that, at least in one connection area, i.e., in an area to be connected to the connector, is larger than the first diameter of the through-bore and smaller than or equal to the second diameter of the through-bore. The line can, in particular, be a hydraulic line, for example, a high-pressure line, as is known per se for hydraulic systems with regard to size, material, and wall thickness.

[0014] According to the further method step c), a fixing means is inserted into the through-bore of the connector. The fixing means serves in particular to temporarily fix the line, in particular in such a way that the position and movement of the line can be adjusted by the fixing means. For example, an interaction between the fixing means and the line can prevent rotation of the line or enable a rotational relative movement between the connector and the line, as described in detail below. Furthermore, a translational movement of the line can be prevented or enabled by the fixing means. In particular, the fixing means can be guided into a fluid guide of the line and thus act on the line from the inside or fix the line from the inside.

[0015] Once the fixing means is positioned in the through-hole, the line with the connection region is inserted into the through-hole of the connector according to method step d), while fixing the line to the fixing means. From the above, it can be seen that the fixing means and the line are inserted into the through-hole in particular from different or opposite sides, so that on one side the line protrudes from the through-hole and on the opposite side the fixing means protrudes from the through-hole. In this case, it can be provided in particular that the line is positioned with its end present in the connector at the step of the through-hole and thus directly adjacent to the region of the through-hole which has a smaller inner diameter than the outer diameter of the line present at the step.

[0016] After inserting the fixing means and the line into the through-bore of the connector, and thus after fixing the line to the fixing means, a rotating relative movement is performed between the line and the connector according to method step e). In other words, the movement of the connector and / or line occurs such that the connector rotates at a different speed than the line. Rotation occurs in particular around the axis of the connector, which can be defined in particular by the through-bore of the connector.

[0017] Given the rotating relative movement between the connector and the cable, friction welding can now take place so that the cable can be fastened to the connector or connected to the connector. In order to form a correspondingly stable and long-lasting connection, the further method step f) provides for the connection area of ​​the cable to be displaced into the area of ​​the first diameter of the through-hole, i.e. into the area with a smaller diameter. This is possible because the relative movement generates heat, which can melt the material of the connector and / or the cable, so that a corresponding displacement with displacement of the molten material is possible. The cable can thus be pulled into the connector by the fixing agent until the cable has reached its desired end position.

[0018] Subsequently, and in particular after the previously melted material has solidified, the fixing agent can be removed from the line and also from the through-bore of the connector according to process step g). Thus, the process can be terminated after process step g), or the line can be connected to the connector.

[0019] The method as described above has significant advantages over the prior art solutions.

[0020] In particular, the method described here makes it possible to connect the cable and the connector particularly easily and cost-effectively. Conventional methods usually require pretreatment of the cables, for example, by machining, such as cutting, to produce a cable with a stepped outer wall. This should make it possible, in particular, to define the final position of the cable in the connector and, if necessary, a position during a welding process.

[0021] The lines can also have a uniform connection area, which can simplify the supply of the line and has a positive effect on the process.

[0022] In contrast, the method described here allows the position of the cable during welding and also the final position to be adjusted simply by axially moving the fixing device. Mechanical pretreatment of the cable is not necessary for this and can therefore be omitted. This eliminates a process step, which can simplify the process and make it more cost-effective. This is because both the mechanical equipment and its operation can be reduced. Furthermore, if poorly performed, mechanical pretreatment can negatively impact state-of-the-art processes. This potentially adverse effect can be eliminated with the method described here.

[0023] Furthermore, the cycle time of the process described here can be shortened compared to the processes known from the prior art, which can make the process particularly profitable.

[0024] In addition, the length of the cable can be reduced by eliminating the need for mechanical processing, which can further reduce costs.

[0025] Furthermore, the connector does not need to be adapted to a stepped design of the cable, allowing for a comparatively simple internal geometry of the connector or through-hole. This allows for simple manufacturing of the connector and also universal applicability. Nevertheless, it is usually possible to prevent the outer diameter of the cable from conflicting with the inner diameter of the connector's through-hole.

[0026] According to the invention, the fixing means is designed as a cylindrical mandrel with a stepped outer wall such that the fixing means has a fixing area for fixing the line and a guide area for guiding the fixing means in the through-bore. In particular, it can be provided that the fixing area has a smaller diameter than the guide area. In this embodiment, the line can be positioned particularly precisely, since the fixing means is guided precisely axially by the guide area without tilting, and the fixing area is always in a radially central position.Accordingly, the outer diameter of the fixing means, in particular of the guide region, can be adapted to the corresponding diameter of the through-bore of the connector, in particular the second diameter, so that the guide region can slide in the through-bore and the fixing means can thus be axially moved or displaced. Furthermore, the outer diameter of the fixing region can be adapted to the inner diameter of the line in such a way that the fixing means can be pushed into the line and thus fix it in a force-fitting manner, for example, by slightly expanding the line.

[0027] It may be important that a fixation is sufficiently strong to allow a rotational movement relative to the connector, but that the fixing means can be removed from the line after the line has been connected to the connector.

[0028] It can further preferably be provided that in method step c) the fixing means is introduced into the through-bore in such a way that the through-bore is introduced with the fixing region into an opening facing the first diameter and thus into an opening of the through-bore positioned adjacent to or on the first diameter, such that the fixing region projects at least into a portion of the second diameter of the through-bore. This makes it particularly easy for the fixing means to be guided axially in the connector in a defined manner in the region of the connector with the smaller diameter, thus ensuring that the fixing region is aligned in a defined manner, and for the line to be easily pushed onto the fixing region in the region of the connector with the larger diameter and thus fixed to the fixing means.Accordingly, this design can be advantageous for a defined alignment of the cable in the connector and thus for a high-quality connection between the cable and the connector.

[0029] It can also be advantageous if the cable and connector are molded from a single plastic. This allows the process to be carried out particularly effectively. Plastics generally have a low melting point, so a rotational relative movement between the connector and cable usually melts the respective materials without any problems. Therefore, friction welding as described here can be carried out effectively, creating a stable and permanent connection between the cable and connector.

[0030] For example, the line can be made of a thermoplastic material, such as polyamide (PA). This can provide high stability combined with a low melting point. For example, in this embodiment, but not limited to this, the line can be designed as a high-pressure line. Alternatively or additionally, the connector can also be made of a suitable thermoplastic material, such as polyethylene (PE), polyetheretherketone (PEEK), or acrylonitrile butadiene styrene (ABS).

[0031] Furthermore, it can preferably be provided that the line has a uniform outer diameter along its length. In particular, it can be provided that the outer diameter of the line has the same value at the connection region and at a region to be positioned outside the connector. The outer diameter can in particular be the diameter of the outer wall of the line, which is in particular cylindrical. In this embodiment, a conventional line can therefore be used which does not require any mechanical pretreatment before being connected to the connector, for example such that the outer diameter is stepped in or at the connection region. Rather, the line can have the same outer diameter at essentially every position. As a result, the method can be carried out with reduced process steps and is therefore particularly process-economical.

[0032] Furthermore, it can preferably be provided that the through-bore of the connector has exactly two different diameters. In this embodiment, the connector or its through-bore can be designed with a particularly simple geometry. This allows the connector to be easily manufactured and also universally applicable, which can further increase process efficiency.

[0033] Further preferably, it can be provided that the connector is rotated in method step e) and the line is stationary in method step e), i.e. in particular with regard to a rotational movement. Alternatively or additionally, it can be provided that step f) takes place by an axial displacement of the connector, wherein the line is stationary in method step e), i.e. in particular with regard to an axial translational movement. In particular in this embodiment, the connector can thus rotate and / or be axially displaced during friction welding and the line can be stationary with regard to a rotation and / or an axial translational movement. This can enable a particularly simple connection, since the connector can be moved easily in a rotational and / or axial translational manner due to its size, whereas the line can be moved more difficultly, in particular in a rotational manner, due to its possible length.Thus, a device can be provided to move the connector axially, translationally, and rotationally, enabling a simple design. Furthermore, this method makes it possible to connect the connector and cable even in confined spaces.

[0034] For further advantages and technical features of the method for connecting a line to a connector, reference is made to the description of the method for assembling a hydraulic system, the figures and the description of the figures.

[0035] The present invention further relates to a method for assembling a hydraulic system, in particular a hydraulic coupling system, for example for a motor vehicle. Within the scope of the method for assembling the hydraulic system, a method for connecting a line to a connector is used, as described in detail above. Accordingly, part of the invention also includes the use of a method for connecting a line to a connector, as described above, for assembling a hydraulic system.

[0036] Such a hydraulic clutch system, which is to be assembled or whose components are to be connected to one another, comprises, in particular, a clutch master cylinder that can be controlled by a piston rod and thus conveys hydraulic fluid from a reservoir to a clutch slave cylinder, or vice versa, from the clutch slave cylinder to the reservoir. Hydraulic fluid can also be conveyed from the clutch slave cylinder to a clutch, such as a clutch housing, or vice versa. Hydraulic lines are designed, in particular, as pressure lines, between the hydraulic functional elements, such as the clutch master cylinder, clutch slave cylinder, clutch housing, and reservoir.Especially when connecting the hydraulic functional elements and the hydraulic lines, connectors are often used that are connected to the hydraulic line and are connected to a corresponding connection of the functional element.

[0037] Thus, the method described here can be used in particular to connect hydraulic functional elements to other hydraulic functional elements, i.e., to assemble the hydraulic system. For this purpose, the connector can be connected to the line, as described above, and the connector can then be connected to a corresponding port of a hydraulic functional element.

[0038] For further advantages and technical features of the method for assembling a hydraulic system, reference is made to the description of the method for connecting a line to a connector, the figures and the description of the figures.

[0039] In the following, a particularly preferred embodiment of the invention is explained with reference to the accompanying drawings, whereby it is explicitly pointed out that the subject matter of the invention is not limited to the described embodiments. They show: Fig. 1 a schematic sectional view through a connector for carrying out a method according to the invention; Fig. 2 a schematic view of a fixing means for carrying out a method according to the invention; Fig. 3 a schematic sectional view through the connector from Fig. 1, in which the fixative according to Fig. 2 is inserted; Fig. 4 a schematic view of a line for carrying out a method according to the invention; Fig. 5 a schematic sectional view through the connector from Fig. 1, in which the fixative according to Fig. 2 and the management according to Fig. 4 is inserted before friction welding; Fig. 6 a schematic sectional view through the connector from Fig. 1, in which the fixative according to Fig. 2 and the management according to Fig. 4 is inserted after friction welding; and Fig. 7 a schematic sectional view through the connector from Fig. 1, which is connected to the line Fig. 4, with the fixing agent removed from the line.

[0040] In the Fig. 1 shows a connector 10 that can be provided for connection to a line 12, such as, in particular, a hydraulic line. In particular, the connector 10 and the connected line 12 can be part of a hydraulic clutch system for a vehicle.

[0041] It can be seen that the connector 10, which is designed as a male connector, has a stepped through-bore 14, such that the through-bore 14 has at least a first diameter 16 and a second diameter 18, wherein the first diameter 16 is smaller than the second diameter 18. Furthermore, a step 20 is provided between the first diameter 16 and the second diameter 18. Furthermore, the connector 10 comprises on its outer circumference, in a manner known per se, a groove 22 for receiving a sealing means 42, such as an O-ring, and a groove 24 for fixing the connector 10 to a corresponding connection.

[0042] In the Fig. 2 shows a fixing means 26, which is designed as a cylindrical mandrel with a stepped outer wall 28 such that the fixing means 26 has a fixing region 30 for fixing the line 12 and a guide region 32 for guiding the fixing means 26 in the through-bore 14. The fixing region 30 has a smaller diameter than the guide region 32.

[0043] In the Fig. 3 shows that the fixing means 26 has been inserted into an opening 34 of the through-bore 14 facing the first diameter 16, with the fixing region 30 extending at least into a portion of the second diameter 18. Accordingly, the guide region 32 can be guided in the region of the second diameter 18 of the through-bore 14.

[0044] The Fig. 4 shows the line 12 that is to be connected to the connector 10. With regard to the line 12, as well as the connector 10, it can be provided, in particular, that they are molded from a particularly thermoplastic material. Furthermore, with regard to the line 12, it is provided that it has an inner diameter and an outer diameter, wherein at least the outer diameter is the same at a connection area 36, ​​which is intended to be connected to the connector 10, and at a area 38 to be positioned outside the connector 10. Furthermore, the outer diameter, at least at the connection area 36, ​​is larger than the first diameter 16 of the through-bore 14 and smaller than or equal to the second diameter 18 of the through-bore 14.

[0045] In the Fig. 5 shows that the line 14 is pushed with the connecting portion 36 onto the fixing portion 30 of the fixing means 26, whereby the line 12 is fixed to the fixing portion 30 in a force-fitting manner. Furthermore, the line 14 rests against the step 20. This can be achieved by inserting the line 12 into the through-bore 14 through an opening 40 arranged opposite the opening 34.

[0046] Friction welding can now take place by performing a rotating relative movement between the line 12 and the connector 10, whereby the connection region 30 of the line 12 is displaced into the region of the first diameter 16 of the through-bore 14. For this purpose, it can be provided that the connector 10 is rotated while the line 12 remains stationary, and that an axial translational displacement of the connector 10 takes place while the line 12 remains stationary.

[0047] This allows the cable 12 to be fixed to the connector 10 by means of friction welding. This is shown in the Fig. 5 shown.

[0048] The fixative can then be removed from the line 12. This is shown in the Fig. 7 shown. List of reference symbols 10 Connector 12 Line 14 through hole 16 diameters 18 diameter 20th level 22 grooves 24 grooves 26 Fixatives 28 Outer wall 30 Fixing area 32 Management area 34 Opening 36 Connection area 38 Area 40 Opening 42 Sealants

Claims

[1] Method for connecting a line (12) to a connector (10) of a hydraulic coupling system, the method comprising the following method steps: a) providing a connector (10) with a stepped through-bore (14) such that the through-bore (14) has at least a first diameter (16) and a second diameter (18), the first diameter (16) being smaller than the second diameter (18); b) providing a line (12) having an outer diameter which, at least at a connecting region (36), is greater than the first diameter (16) of the through-bore (14) and is less than or equal to the second diameter (18) of the through-bore (14); c) introducing a fixing means (26) into the through-bore (14), the fixing means (14) serving to temporarily fix the line (12); d) inserting the line (12) with the connecting region (36) into the through-bore (14) of the connector (10) while fixing the line (12) to the fixing means (26); e) performing a rotating relative movement between the line (12) and the connector (10); wherein f) the connecting region (36) of the line (12) is displaced into the region of the first diameter (16) of the through-bore (14); and g) removing the fixing means (26) from the line (12), wherein the fixing means (26) is designed as a cylindrical mandrel with a stepped outer wall (28) such that the fixing means (26) has a fixing region (30) for fixing the line (12) and a guide region (32) for guiding the fixing means (26) in the through-bore (14). [2] Method according to claim 1, characterized byin method step c) the fixing means (26) is introduced into the through-bore (14) in such a way that it is introduced with the fixing region (30) into an opening (34) of the through-bore (14) facing the first diameter (16) in such a way that the fixing region (30) projects at least into a part of the second diameter (18) of the through-bore (14). [3] Method according to one of claims 1 to 2, characterized by that the cable (12) and the connector (10) are formed from a plastic. [4] Method according to one of claims 1 to 3, characterized by that the line (12) has a uniform outer diameter over its length. [5] Method according to one of claims 1 to 4, characterized by that the through hole (14) of the connector (10) has exactly two different diameters (16, 18). [6] Method according to one of claims 1 to 5, characterized bythat the connector (10) is rotated in process step e) and the line (12) is fixed in process step e). [7] Method according to one of claims 1 to 6, characterized by that step f) is carried out by an axial translational displacement of the connector (10), wherein the line (12) is fixed in process step f). [8] Method for assembling a hydraulic system, wherein a method according to one of claims 1 to 7 is used within the scope of the method for assembling the hydraulic system. [9] Use of a method according to any one of claims 1 to 7 for assembling a hydraulic system.

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