EP3818600B1 - Production of press-fit and crimp connections in a vice - Google Patents

Description

technical field

The present invention relates to a method for connecting a strand element to a connection element using a method for deforming, in particular a crimping method, at least in parts of the manufacturing method, using a vise or vise. The method is used in particular to connect a pipe to a termination or connection element, or, for example, to connect a cable to a cable lug.

State of the art

In the example of connecting a cable with a cable lug, post-processing may be required to completely manufacture the workpiece. This post-processing may include drilling and/or welding. In certain cases, a great deal of pressure is exerted on the crimp connection, so that this crimp connection can be damaged or destroyed, and the joining process thus suffers significant losses in quality.

The GB710,974 discloses a holder with two receivers for holding a barrel during crimping of the barrel to a wire, the receivers each having two semi-openings with two diameters.

Description of the invention

It is therefore an object of the invention to at least partially overcome these disadvantages using means that are as simple as possible in terms of construction.

The object is solved by the subject matter of the independent claims. Advantageous developments of the invention are specified in the dependent claims, the description and the accompanying figures.

A system according to the invention, which is set up to establish a mechanical connection between a line element and a connection element, has the following components:
A pair of receptacles, each receptacle having a face with a groove and a well. The groove is suitable for accommodating the connection element. For this purpose, the groove can be designed in such a way that it encloses the connecting element at a distance of, for example, less than 1 mm or less than 0.1 mm. In some embodiments, the fillet may be configured to provide a slight pinch of the terminal when the pair of receptacles encircle the terminal. The fillet can be arranged in the middle of the end face. The fillet can have a semicircular, oval, triangular or polygonal shape. The shaft can be arranged essentially in the middle of the end face. The shaft can be completely enclosed by the material of the receiving element, but it can also be open, at least partially, on one side. The open side can be designed in such a way that elements of a slide can be accommodated at this point.

The system also has a pair of press inserts. In this case, each press insert has an end face with a groove that extends over the entire narrow side of the end face. The groove of the press inserts has a smaller diameter than the groove of the receiving elements, so that the press insert is suitable for forming the connection element. The press insert is set up to be arranged in the shaft of the connecting element. This is designed so that when the die is placed in the well, the fillet of the die is substantially flush with the fillet of the receptacle, apart from the different diameters and shapes of the fillets. In one embodiment, the press insert can protrude up to 0.2 mm. This has the advantage that the clamping forces are essentially introduced into the workpiece via the press inserts. In a non-claimed embodiment, the

Combination of receiving element and press insert, or combination of receiving element, press insert and adapter plate, designed in one piece.

The receiving elements and the press inserts are arranged in a vise or vise which, depending on the embodiment, can be operated in a vertical and/or horizontal installation position. A vise or vise is commonly used to clamp or clamp certain workpieces for machining. However, the machining of the workpieces is carried out by other machines, e.g. by milling machines. In the present invention, on the other hand, the vise or vise is used for machining, in particular for forming, the workpieces. This is particularly advantageous because it means that standard machine tools, such as a vice or vise, can be used for the production of forming workpieces, for example a crimp connection. Only the specific forming or crimping tools, such as the receiving elements and the press inserts, have to be used in these standard machine tools.

The system also has a clamp. The clamping bracket has an end face with a groove that is suitable for receiving the connection element. For this purpose, the groove can be designed in such a way that it encloses the connecting element at a distance of, for example, less than 1 mm or less than 0.5 mm. The fillet can be arranged in the middle of the end face. The fillet can have a semicircular, oval, triangular or polygonal shape. Furthermore, the clamping bracket has a stop which is arranged on a first side of the clamping bracket. In one embodiment, the stop does not completely close the groove of the clamping bracket, but is suitable for allowing a protruding part of the connection element to protrude beyond the connection element. In one embodiment, the stop is moveable.

The system, in making the connection, takes the string member with the terminal member located at a first end of the string member up to the stop and places the pair of crimping inserts around a central portion (viewed in the axial direction) of the terminal member. The middle area of the connection element can include the middle third, but it can also extend to one end of the connection element. The press inserts and the receiving elements are therefore designed in pairs so that they can be positioned as symmetrically as possible around the central area of the Can arrange connection element and thus achieve a symmetrical and high-quality transformation. In one embodiment, more than two each of dies and receptacles are used in manufacture.

In one embodiment, the line element is a tube that can be used, for example, for tube connections in sanitary technology.

In one embodiment, the string element is an electrical line or a bundle of lines, so that establishing a mechanical connection causes an electrical connection to be established at the same time. In this case, the method mentioned makes it possible to produce an electrical connection with a low contact resistance in a relatively simple manner.

In one embodiment, the strand element consists at least partially of plastics, in particular thermoplastics, of soft metals, in particular of aluminum or copper or aluminum and/or copper alloys, and/or of steel and/or of combinations of these materials. In one embodiment, the connection element consists at least partially of plastics, in particular thermoplastics, of soft metals, in particular of aluminum or copper or aluminum and/or copper alloys, and/or of steel and/or of combinations of these materials. In one embodiment, the strand element and/or the connection element is/are coated with plastics, with paint, with metals, in particular with nickel, tin, zinc, silver. The measures mentioned have the advantageous effect of further improving the conductivity, in particular the transition and overall resistance and/or the corrosion resistance, strength properties and/or flow properties of the workpiece produced.

In one embodiment, the pair of flutes of the dies form a hexagon. This is particularly advantageous for cables with a certain thickness that are to be fixed during assembly.

In one embodiment, the system also has a welding tool for the integral connection of the strand element and the connecting element. This enables a connection of the highest quality, both mechanically and electrically. At this time, welding occurs on some types of welding tools under high pressure. The axial force used can, for example, be greater than 1 kN, in particular greater than 10 kN. A system according to the invention ensures that the reshaping, for example the described crimping process, produces a connection of such high quality that the welding process forces that occur do not result in breakage or deterioration of the connection. In one embodiment, a pressure connection welding process, such as spot friction welding, is used as the welding method. This advantageously creates a very compact welded structure.

In one embodiment, the stop is closed by means of a closing spring. This is particularly advantageous when the stop is part of a machine with which the crimping process is carried out fully automatically or semi-automatically; because this allows the workpiece to be released very easily, e.g. for removal, and closed again during the manufacturing process.

In one embodiment, the pair of receiving elements is driven by the jaws or jaw attachment of the vise or vise. In this case, only one of the jaws can be designed to be movable. This means that large forces can be used in the forming process in a reproducible manner.

In one embodiment, at least one side of the vise or vise is integrated into a tool unit that is moved along a slide bar. This enables simple and effective integration into the manufacturing process.

In one embodiment, the system has a further clamping element, which is suitable for accommodating the string element and is in particular moved together with the tool unit. This further improves the manufacturing process because it enables or at least simplifies the exact fixing of the workpiece at the beginning of the manufacturing process.

In an advantageous embodiment, it is provided that a holding device is used as part of the receiving element for receiving the line element and a correspondingly arranged die on the tool unit is provided for positioning and aligning the connection element relative to the line element. The holding device and the Correspondingly arranged dies are mounted such that they can be displaced horizontally and/or vertically relative to one another by means of at least one compensating element. Furthermore, the die has a clamping hook, which is made to correspond to a tab of the connecting element and thus allows the positioning and alignment of the connecting element by means of the movement of the clamping hook.

In one embodiment, the connecting element has a tab. The lug can be designed as a screw lug. The tab may have an opening. Such connection elements with tabs are required for many applications, for example in industry or automotive engineering. For this type of connection elements, an embodiment of the clamp can be selected in which the stop does not completely close the groove of the clamp, but which is suitable for allowing a protruding part of the connection element to protrude beyond the connection element.

In one embodiment, the system has cooling and/or preheating. This can improve process stability and/or tool life. In addition, cooling and/or preheating the workpiece can improve the crimping and/or welding properties, for example the optimal process temperature can be set and maintained for each material combination of strand element and connection element. In one embodiment, the preheating can be used to support the forming, for example in the case of workpieces that have thermoplastics.

The invention also includes a method for producing a mechanical (non-positive and, depending on the choice/shaping of the press insert, at the same time positive) connection between a strand element and a connection element. Components are used as specified above. According to the method, the line element is arranged with the connecting element on a stop of a clamping bracket. After being placed in the system, the workpiece is arranged on the stop in such a way that the connection element is in direct contact with the stop. This improves the reproducibility and/or quality of manufacture. Finally, a material connection between the line element and the connection element is produced by means of a welding tool. This enables a connection of the highest quality, both mechanically and electrically. In the process, welding happens to some Types of welding tools under high pressure. The axial force used can, for example, be greater than 1 kN, in particular greater than 10 kN. The method mentioned ensures that the reshaping, for example by the crimping method described, produces a connection of such high quality that the welding process forces that occur do not result in the connection breaking.

In one embodiment, the line element is arranged in the connection element in such a way that a predefined distance remains between a first end of the line element and the inside of the end face of the connection element. In this way, an expansion, e.g. due to thermal effects, of the line element can be compensated for during production, so that the line element does not move in the connection element during production and thus deteriorate the connection. In one embodiment, a stop for the strand (the strand element) can also be provided.

In an advantageous embodiment of the method, it is provided that a pair of press inserts is arranged around a central area of the connection element. The middle area of the connection element can include the middle third, but it can also extend to one end of the connection element.

It has also proven to be advantageous to move the line element and the connection element vertically and/or horizontally in relation to one another until the connection element is optimally positioned and aligned relative to the line element.

Furthermore, it is advantageously provided to cool and/or preheat at least part of the system, the strand element and/or the connecting element during the forming process and/or during the subsequent welding process. This avoids excessive temperature differences between the individual components of the system or the strand element or the connection element during the crimping and/or welding process and thus improves the process quality and the connection properties between the strand element and the connection element.

Brief character description

Fig. 1a

die schematische Darstellung einer Ausführungsform eines Presseinsatzes;

Fig. 1b

die schematische Darstellung einer Ausführungsform eines Aufnahmeelements;

Fig. 1c

die schematische Darstellung einer Ausführungsform eines Spannbügels;

Fig. 2a

die schematische Darstellung einer Ausführungsform eines Systems, das mittels eines Schraub- oder Spannstocks realisiert wurde;

Fig. 2b

ein geschlossener Schraub- oder Spannstock am Ende des Umformungsprozesses;

Fig. 3

die schematische Explosionszeichnung einer Ausführungsform des Systems mit einer Matrize und einer Haltevorrichtung.

An advantageous exemplary embodiment of the invention is explained below with reference to the accompanying figures. Show it:

Fig. 1a

the schematic representation of an embodiment of a press insert;

Fig. 1b

the schematic representation of an embodiment of a receiving element;

1c

the schematic representation of an embodiment of a clamping bracket;

Figure 2a

the schematic representation of an embodiment of a system that was realized by means of a vise or vise;

Figure 2b

a closed vise or vise at the end of the forming process;

3

the schematic exploded view of an embodiment of the system with a die and a holding device.

Fig. 1a shows the schematic representation of a press insert 300. It is clearly visible that the groove 315 extends over the entire narrow side of the end face 310 of the press insert 300. The groove 315 is designed in such a way that it has a smaller diameter than the groove 215 of the receiving elements 200 (see FIG Fig. 1b ). As a result, the press insert 300 is suitable for forming the connecting element 150 (see Figure 2a ) to accomplish. The fillet 315 is configured in the embodiment shown to have a hexagonal shape when the die 300 is used in pairs.

Fig. 1b shows the schematic representation of a receiving element 200. The receiving element 200 has a groove 215 on the end face 210. FIG. Furthermore, the receiving element 200 has a shaft 230 . In the embodiment shown, this is open at the bottom. The receiving element 200 is designed in such a way that when the pressing insert 300 (see Fig. 1a ) is disposed in the well 230, the fillet 315 of the die 300 is substantially aligned with the fillet 215 of the receptacle 200, except for the different diameters and shapes of the fillets 215 and 315. In one embodiment, the die may be up to 0.2 mm to preside

1c shows the schematic representation of a clamp 400. The clamp 400 has a groove 415 on the end face 410 (this on in 1c down) up. The clamping bracket 400 has a stop 450 on a first side 420 . In the embodiment shown, the clamp 400 is designed to be movable. It can be clearly seen that the stop 450, when it is guided down and closed, the groove 415 of the Clamping bracket 400 is not completely closed, but is suitable for allowing a protruding part of the connection element to protrude over the connection element.

Figure 2a shows the schematic exploded view of a system 10 according to the invention, which was realized by means of a vise or vise. The elements of the press insert 300 and the receiving element 200 are attached to an adapter plate 290 which is arranged on a carriage track 530 . The elements of the press insert 300 and the receiving element 200 on an adapter plate 290 can also be made in one piece. The adapter plate 290 enables simple assembly on a vise or vise 500. It can be clearly seen that the elements of the press insert 300, receiving element 200 and adapter plate 290 are arranged in pairs opposite one another. A line element 100 and a connection element 150 are arranged in the middle of the system 10 . The connection element 150 has a tab 158 . The connector 150 is shown after the reshaping and opening of the system 10; thereby, by closing the movable element of the vise or vice 500, the central area 155 of the connecting element 150 was pressed into a hexagonal shape. A vise or vice 500 can exert enormous forces on the workpiece in a predictable manner and ensure a satisfactory repeatability of the movement sequences and thus bring about a high-quality forming.

Figure 2b shows a closed vice or vice immediately after the end of the forming process. Only the tab 158 and an upper part of the connecting element 150 can be seen. The change in the elements of the vise or vise 500 is, particularly in comparison with Figure 2a , clearly visible. In this case, the pressing insert 300 is covered by the closed receiving element 200 . A welding tool 600 (eg based on a spot friction welding tool, a sonotrode, an electrode or a hot stamp) is shown above the connection element 150 . The welding tool 600 can be used to achieve a cohesive connection between the strand element 100 and the connecting element 150 after the forming, and thus further improve the quality of the connection.

In one embodiment of the 3 the system 10 is arranged vertically. The receiving element 200 is floatingly mounted in the vertical direction on a lower tool unit 550 by a spring mechanism and can be moved in the open vise position move relative to the die 300. The receiving element 200 is designed in such a way that, in addition to the connecting element 150 , it also receives the strand element 100 in a separate recess/mold cavity outside the forming area by means of a die 580 and a holding device 590 . The line element 100 and the connecting element 150 are placed horizontally in the receiving element 200, the connecting element 150 being fixed via a clamp 400 and the line element 100 via a separate clamping element 540 on the receiving element 200 or on a holding device 590 as part of the receiving element 200. In addition, the die 580 for holding and positioning the connecting element 150 in the 3 shown. The holding device 590 and thus the receiving element 200 can be displaced in the vertical and/or horizontal direction in relation to the matrix 580. This allows for easier positioning and retention of the connector member 150 relative to the string member 100. This is preferably accomplished by a balancing member 510, which may be a spring, hydraulic cylinder, or similar mechanical balancing member. The compensating element 510 is preferably arranged on the lower tool unit 550 below the die 510 and/or below the holding device 590 of the connecting element 200. In the example shown 3 the die 580 is held by a stamp-shaped hydraulic compensating element 510 and the holding device 590 of the connecting element 200 by means of a spring as a compensating element 510. The die 580 also has a clamping hook 585 which grasps the tab 158 of the connecting element 150 and thus supports positioning of the connection element 150 is used. By designing according to 3 In this insertion position, the receiving element 200 is arranged higher than the press insert 300 by the spring mechanism. This has the advantage that tilting or slipping of the connecting element 150 and the strand element 100 on the relatively narrow press insert 300, which otherwise projects relative to the receiving element 200, whose width usually • 10 mm is avoided.

The figures are only schematic representations and only serve to explain the invention. Elements that are the same or have the same effect are provided with the same reference symbols throughout.

REFERENCE LIST

10

system

100

Pipe, line, bundle of lines

110

first end of the tube

150

connection element

155

middle area of the connecting element

157

face

158

tab

200

receiving element

210

face

215

throat

230

shaft

290

adapter plate

300

press insert

310

face

315

throat

400

clamp

420

first page

450

attack

460

closing spring

490

another clamping element

500

Vice or vise

510

compensation element

520

Jaws or jaw attachment

530

sled track

540

clamping element

550

tool unit

560

cooling or preheating system

570

slide bar

580

die

585

tension hook

590

holding device

600

welding tool

Claims (14)

1. System (10) configured to produce a mechanical connection between a strand element (100) and a connection element (150), having:

   - a pair of receiving elements (200), wherein each receiving element (200) has a face side(210) with a groove (215) which is suitable for receiving the connection element (150), and has a shaft (230),

   - a clamping bracket (400) with a face side (410) which has a groove (415) which is suitable for receiving the connection element (150), and has a stop (450) which is arranged on a first side (420) of the clamping bracket (400),

   - a pair of pressing inserts (300), wherein each pressing insert (300) has a face side (310) with a groove (315) which extends over the entire narrow side of the face side, and wherein the pressing insert (300) is configured to be arranged in the shaft (230) of an assigned receiving element (200), and, when the pressing insert (300) is arranged in the shaft (230), the groove (315) of the pressing insert (300) is substantially aligned with the groove (215) of the receiving element (200),

   - a screw vice or clamp vice (500), wherein the receiving elements (200) and the pressing inserts (300) are arranged in the screw vice or clamp vice (500) so that, when the connection is produced, the system (10) receives the strand element (100) with the connection element (150), which is arranged on a first end of the strand element (100), up to the stop (450) and arranges the pair of pressing inserts (300) around a middle region (155) of the connection element (150).
2. System (10) according to Claim 1,

   wherein the strand element (100) consists at least partially of plastics, in particular of thermoplastics, of soft metals, in particular of aluminium or copper or aluminium alloys and/or copper alloys, and/or of steel and/or of combinations of said materials,

   the connection element (150) consists at least partially of plastics, in particular of thermoplastics, of soft metals, in particular of aluminium or copper or aluminium alloys and/or copper alloys, and/or of steel and/or of combinations of said materials, and

   the strand element (100) and/or the connection element (150) are/is coated with plastics, with lacquer, with metals, in particular with nickel, tin, zinc, silver.
3. System (10) according to either of the preceding claims,
   wherein the pair of grooves (215) of the pressing inserts (300) form a polygon, in particular a hexagon.
4. System (10) according to either of the preceding claims,
   wherein the system (10) furthermore has a welding tool (600) for materially bonded connection of the strand element (100) and the connection element (150) .
5. System (10) according to one of the preceding claims,
   wherein the pair of receiving elements (200) is able to be driven by the jaws (520) or the jaw attachment of the screw vice or clamp vice (500).
6. System (10) according to Claim 5,
   wherein at least one jaw side of the screw vice or clamp vice (500) is integrated into a tool unit (550) which is movable along a slide rod (570) relative to a second tool unit (550).
7. System (10) according to Claim 6,
   wherein a holding device (590) serves as part of the receiving element (200) for receiving the strand element (100) and a matrix (580) arranged correspondingly on the tool unit (550) serves for positioning and orienting the connection element (150) relative to the strand element (100).
8. System (10) according to Claim 7,
   wherein the holding device (590) and the correspondingly arranged matrix (580) are mounted so as to be displaceable horizontally and/or vertically relative to one another by means of at least one compensation element (510).
9. System (10) according to either of Claims 7 and 8, wherein the matrix (580) has a clamping hook (585) corresponding to a tab (158) of the connection element (150) and thus permits the positioning and orientation of the connection element (150) by means of the movement of the clamping hook (585).
10. System (10) according to one of the preceding claims,
    wherein the system (10) furthermore has a cooling system and/or a pre-heating system (560) by way of which at least parts of the system (10), the strand element (100) and/or the connection element (150) can be heated or cooled during the forming process and/or during the subsequent welding process.
11. Method for producing a mechanical connection between a strand element (100) and a connection element (150) using a system according to Claim 1, comprising the steps of

    - arranging the strand element (100) with the connection element (150), which is arranged on a first end (110) of the strand element (100), on the stop (450) of the clamping bracket (400);

    - arranging the pair of pressing inserts (300) around a middle region (155) of the connection element (150);

    - connecting the strand element (100) and the connection element (150) in a materially bonded manner by means of a welding tool (600).
12. Method according to Claim 11,
    wherein the strand element (100) is arranged in the connection element (150) in such a way that a predefined spacing remains between a first end (110) of the strand element (100) and the inner side (156) of the face side (157) of the connection element (150) .
13. Method according to either of Claims 11 and 12,
    wherein the strand element (100) and the connection element (150) are displaced vertically and/or horizontally with respect to one another until there is an optimal positioning and orientation of the connection element (150) relative to the strand element (100).
14. Method according to one of Claims 11 to 13, comprising the further step of:

    - cooling or heating at least a part of the system (10), the strand element (100) and/or the connection element (150) during the forming process and/or during the subsequent welding process.

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