EP2230732A1 - Device for attaching a cable to a connection element - Google Patents

Abstract

The device (111) has an upper die (17) and a lower die (119) with a pressing surface (123) to press a connection element (15) in a predetermined area between the upper die and lower die. A recess (133) is provided between the upper die and the lower die outside the pressing surface. The recess is designed to accommodate a part of the cable or a section of the connection element. The distance between the pressing surface and an edge (135) of the recess is less than the length, width and depth of the recess. The recess is formed as trough-shaped. An independent claim is also included for a method for attaching a cable to connection element.

Description

The present invention relates to an apparatus and method for striking a conduit to a connector. The apparatus includes an upper die and a lower die, each having a pressing surface to press the conduit and the connecting member in a predetermined area between the lower die and the upper die.

Such devices and methods are used for example in electrical connection technology to produce a no longer detachable connection between a line and a connecting element. The line and the connecting element are connected to each other by a plastic deformation, which is caused by a pressing force. By such a connection, the lead and the connecting element can be further electrically contacted, wherein the connecting element as any contact element, e.g. as a plug can be formed.

The connection between the conductor and the connecting element can be produced for example by crimping or splicing. When crimping usually preformed fasteners are used whose dimensions, in particular their length, are matched to the cross section of the line. Furthermore, crimping tools have predetermined profiles in order to bring about a predeterminable deformation of the line and the connecting element and thereby the crimped connection in one form the desired shape. When splicing an endless belt is used instead of a preformed connecting element.

A crimp connection can be produced in the simplest case by means of a crimping tool. However, if a large number of crimp connections are to be produced in a short time, for example, in the manufacture of special cables with special contact elements, automated devices are used. Such a device is in Fig. 1 shown schematically and includes an upper die, in which engages a stamp-like lower die. The line and the connecting element pass between pressing surfaces of the upper and lower dies and are pressed together by means of a pressing force which is exerted on the upper or lower die.

Since the outer shape of the crimped connection is to be defined by the shape of the pressing surfaces of the upper and lower dies, an extremely small gap size is required between the flanks or side surfaces of the upper and lower dies. In practice, however, various types of defects may occur in the manufacture of the crimped connection. For example, the connecting element may already be deformed before it reaches the device. The conduit and the connecting element may be displaced or twisted with respect to a central axis of the upper and lower dies. Furthermore, the upper and lower dies can be displaced relative to each other.

As a result, so-called Fehlcrimpung occur in the material of the line and / or the connecting element from the predetermined area between the pressing surfaces emerges and passes between the flanks or side surfaces of the upper and lower die. As a misdirected in this way material of the line and / or the connecting element is distributed mostly asymmetrically with respect to the central axis of the upper and lower die, acting in Fehlcrimpungen due to the large pressing force large torques on the side surfaces of the upper and lower die. As a result, the upper and lower dies can be shifted against each other, and high mechanical stresses occur. These tensions can deform or even destroy the upper and lower dies. For example, the two side surfaces of the upper die may be bent apart by the tensions until a portion of the upper die breaks off. Furthermore, the side and pressing surfaces of the upper and lower die are heavily stressed by the mechanical stresses, so that it can lead to the formation of grooves in the pressing surfaces. Thus, false crimps reduce the life of the upper and lower dies.

It is therefore the object of the invention to provide a device and a method of the type described above for striking a line to a connecting element, by which the likelihood of damage to a top and a bottom die is reduced when a faulty striking occurs.

This object is achieved by a device having the features of claim 1 and in particular by the fact that between the upper die and the lower die at least one recess is provided outside the pressing surfaces, which is adapted to receive a part of the conduit and / or a portion of the connecting element , Misguided material of the conduit and / or the connecting element, which leaves the area between the pressing surfaces of the upper and lower mold due to a faulty stop, is received in the at least one recess and thus prevented from moving farther away from the area between the pressing surfaces ,

Because the misguided material is closer to the pressing surfaces due to the recess altogether, i. the distance between the volume elements of the misguided material and the pressing surfaces is shortened by the presence of the recess in total, the lever arm of undesired torques acting on the side surfaces of the upper and lower dies is shortened by the reception of the material in the recess. Consequently, the undesirable torques and the resulting compressive and tensile stresses on the upper and lower dies are reduced. The load limits at which a deformation or damage of the upper and lower mold can occur are thus considerably higher due to the reduced torques, which leads to a longer service life of the upper and lower dies.

The recess between the upper and the lower die also causes both the side and the pressing surfaces of the upper and lower die are less stressed due to the lower compressive and tensile stresses when a faulty striking occurs. For example, the formation of grooves on the pressing surfaces is reduced, so that thereby the life of the upper and lower die is extended. Consequently, it is possible to produce a larger number of stops or crimps with the same upper or lower die.

Advantageous embodiments of the invention are described in the dependent claims, the description and the drawings.

Advantageously, the distance between one of the boundary surfaces and at least one edge of the recess is less than the length, width and Depth of the recess. In other words, the recess is in the immediate vicinity of one of the pressing surfaces to receive misdirected material of the conduit and / or the connecting element immediately after leaving the predetermined region between the pressing surfaces. As a result, the surface portion on the side surfaces of the upper and lower dies is reduced to the misguided material can exert a force before it is absorbed by the recess. Further, the torque exerted on the side surfaces of the upper and lower dies is minimized by the arrangement of the recess near the pressing surfaces, since the length of the lever arm that can be generated by the misdirected material is minimized.

The recess is advantageously formed as an undercut or trough-shaped so that the forces exerted by the misdirected material in the region of the recess on the upper or lower die, are rather tangentially oriented, i. opposite to the direction of the actual pressing force, and not perpendicular to the side surface of the upper and Untergesenks. As a result, the torque exerted on the side surfaces of the upper or lower die is additionally reduced. It is also advantageous if the recess has rounded edges, so that the requirements on the edge strength of the material from which the upper and the lower die are made are lower. As a result, the upper and the lower die can be produced more cheaply.

The depth of the recess is preferably less than the length and the width of the recess. In other words, the recess is rather flat, so that misguided material slides along the side surface of the upper and / or lower mold along the line and / or the connecting element, and thus exerts a tangential rather than a normal force on it. This allows the torque on the side surfaces reduce further. If the recess is provided on a side surface of the lower die, the width of the lower die, which is already low in its upper portion anyway, is reduced less by a shallow recess in this area than by a deep recess. The lower die is thus more stable with a flat elongated recess than with a short and deep recess.

At least one further recess in the upper and / or lower die is advantageously provided outside the pressing surface, and at least two recesses are preferably arranged symmetrically to the pressing surface, since it can not be predicted which type of faulty striking will occur and at which point misdirected Material will leave the area between the pressing surfaces. If a plurality of recesses are provided and / or at least two of them are arranged symmetrically with respect to the pressing surface, it is thus possible to further reduce the likelihood that a displacement or damage of the upper and lower dies will occur in the event of an incorrect attachment of the conduit to the connecting element.

The recess is preferably located on a side surface of the lower die, i. designed as an undercut of the lower part. When the misdirected material enters a recess of the lower die, smaller forces occur perpendicular to the pressing direction than when entering an outer recess of the upper die. In addition, because the misdirected material is closer to the central axis of the device, the torque applied to the side surfaces of the upper and lower dies is lower overall.

Alternatively or additionally, a recess may also be arranged on a side surface of the upper die. In this case, the recess affects as such, less on the strength of the device, since the upper die usually has a larger volume than the lower die.

Another object of the invention is a method for striking a line to a connecting element. The line and the connecting element are thereby pressed into a predetermined area between each of a pressing surface of the upper die and the lower die. A portion of the conduit and / or a portion of the connecting element, when it leaves the area between the pressing surfaces, is received in a recess provided between the upper die and the lower die outside the pressing surfaces to prevent damage to the lower die and / or the upper die ,

Fig. 1

eine schematische Darstellung einer Vorrichtung zum Anschlagen einer Leitung an ein Verbindungselement gemäß dem Stand der Technik,

Fig. 2

eine schematische Darstellung einer erfindungsgemä- ßen Vorrichtung.

Fig. 3a und 3b

jeweils einen vergrößerten Ausschnitt der Fig. 1 bzw. 2.

The invention will be explained below with reference to an advantageous embodiment with reference to the drawings. Show it:

Fig. 1

1 is a schematic representation of a device for striking a line to a connecting element according to the prior art,

Fig. 2

a schematic representation of an inventive device.

Fig. 3a and 3b

each an enlarged section of the Fig. 1 or 2.

Fig. 1 shows a device 11 for striking a line 13 to a connecting element 15 according to the prior art. The device comprises an upper die 17 into which a punch-shaped lower die 19 engages. The upper die 17 and the lower die 19 each have one Pressing surface 21 and 23, respectively, by which the shape of a crimped connection is established, which is produced by the striking of the line 13 to the connecting element 15.

The line 13 may include multiple line strands. The connecting element 15 is shown by way of example as a wire claw, so that a so-called wire crimp is produced by striking the wire to the wire claw. By means of the device 11, however, it is also possible for example to produce an insulation crimp in which insulating material is provided between the connecting element and the conductor.

The upper die 17 is pressed against the lower die 19 by a pressing force acting in the direction of the arrow 25. As a result, the line 13 and the connecting element 15 are plastically deformed, and there is a permanent, no longer releasable connection between them.

A faulty striking of the line 13 to the connecting element 15 occurs, for example, when its right half 15a, as in Fig. 1 represented, is bent incorrectly downwards. Accordingly, when the upper die 17 is pressed against the lower die 19, the right half of the connecting member 15 is outside the predetermined range between the pressing surfaces 21 and 23. As in Fig. 3a As shown, the portion 15a of the connecting member passes between the side surfaces 27 and 29 of the upper and lower dies and causes very large forces to occur due to an extremely small gap required between the side surfaces 27 and 29 for producing the crimped connection. These forces can move the upper die 17 and the lower die 19 against each other. Furthermore, the forces and the resulting torques lead to very high mechanical Tensions in the upper die 17 and the lower die 19, which can be deformed or even destroyed.

A faulty striking of the line 13 to the connecting element 15 can except by a bent connecting element 15, as shown in FIG Fig. 1 is shown, also occur in that the upper die 17 and the lower die 19 are shifted relative to a common central axis 31 against each other. Also, the line 13 and / or the connecting element 15 with respect to the central axis 31 may be moved.

Fig. 2 shows a device 111 according to the invention for striking a line 13 to a connecting element 15, which has a modified lower die 119, with which the problems described above are solved. In contrast to Fig. 1 the lower die 119 on both side surfaces 129 each have a recess 133 into which misdirected material that can escape from the conduit 13 and / or the connecting element 15 is received. The two recesses 133 are formed as an undercut and arranged symmetrically to the central axis 31 and the pressing surface 123 of the lower die 119 so as to accommodate misdirected material on both side surfaces 129 can.

Through the recesses 133, the lower die 119 is tapered below the pressing surface 123, and the width of the lower die 119 is greater in the region of the pressing surface 123 than in the region of the taper. The recesses 133 are trough-shaped and have rounded edges 135 to facilitate entry of the misguided material into the recess 133. Furthermore, there are no increased demands on the edge strength of the material from which the lower die 119 is made.

The depth of the trough-shaped recesses 133 is significantly less than their length along the respective side surface 129. When the misdirected material enters and propagates in the recess 133, only tangential forces and no normal forces are thereby exerted on the side surfaces 129 of the lower die 119. The volume defined by the recesses 133 between the lower die 119 and the upper die 17 is preferably selected so that sufficient misdirected material can be received in the recesses 133. The volume defined by the two recesses 133 may, for example, correspond to the volume of the connecting element 15.

Since the misdirected material is received in the recesses 133, lower forces are exerted on the side surfaces 129 and 27 of the lower die 119 and the upper die 17, respectively, than when using an in Fig. 1 illustrated Untergesenks 19 would be the case. This reduces the likelihood of damaging the upper and lower dies 17 and 119, respectively, and thus extends the life of the entire apparatus 111.

The reduction of the forces acting on the side surfaces 27, 29 and 129 of the upper and lower dies 17, 19 and 119, respectively, is reduced in FIG Fig. 3a and 3b clarified. These show an enlarged section of the Fig. 1 or 2, wherein the line 13 and the connecting element 15 are already pressed into the predetermined range. Material of the connecting member 15 has leaked along the side surfaces 27, 29 and 129 of the upper die 17 and the lower die 19 and 119 from the predetermined range. The misguided material is in Fig. 3a due to the missing recess 133 of the lower die 19 on the average further from the predetermined range than in Fig. 3b and exercises forces with a relatively large Lever arm 37 on the side surfaces 27 and 29 of the upper and lower die 17 and 19, respectively. As a result, significant torques and mechanical stresses on the upper die 17 and the lower die 19 are exercised.

The misguided material is in Fig. 3b received in the recess 133 of the lower die 119 according to the invention. The dimensions of the recesses 133 may preferably be chosen such that in most cases the material picked up no longer contacts one of the side surfaces 27, 29 or 129 over the entire surface. As a result, the material received in the recess 133 exerts little or no force on the side surface 129 of the lower die 119 or on the side surface 27 of the upper die 17, and the resulting lever arm 137 is smaller than that in FIG Fig. 3a shown lever arm 37 significantly shortened.

The shortened lever arm 137 reduces the mechanical stresses within the upper die 17 and the lower die 119. As a result, the likelihood of damage to the upper and / or lower dies 17 and 119, respectively, in the event of a faulty strike of the line 13 to the connecting element 15 is reduced. Further, the side and pressing surfaces 27, 129, 21 and 123 are less stressed by the lower mechanical stresses, so that the formation of grooves, in particular on the surfaces 27 and 123 is less likely. Thus, the life of the upper die 17 and the lower die 119 is lengthened by the recess 133 as a whole, so that larger numbers of crimp connections can be made without having to replace the upper and / or lower die 17 and 119 respectively.

LIST OF REFERENCE NUMBERS

11, 111

device

13

management

15

connecting element

15a

Section of the connecting element

17

upper die

19, 119

lower die

21

Press surface of the upper die

23, 123

Pressing surface of the lower part

25

Arrow, direction of pressing force

27

Side surface of the upper die

29, 129

Side surface of the lower part

31

Center axis of the device

133

recess

135

edge

37

lever arm

137

lever arm

Claims (14)

Device (111) for striking a line (13) to a connecting element (15) having an upper die (17) and a lower die (119) each having a pressing surface (21, 123) around the conduit (13) and the connecting element (15) to press in a predetermined area between the upper die (17) and the lower die (119),
wherein between the upper die (17) and the lower die (119) at least one recess (133) is provided outside the pressing surfaces (21, 123), which is designed to form part of the duct (13) and / or a portion of the connecting element (13). 15). Device according to claim 1,
characterized in that
the distance between one of the pressing surfaces (21, 123) and at least one edge (135) of the recess (133) is less than the length, width and depth of the recess (133). Apparatus according to claim 1 or 2,
characterized in that
the recess (133) is formed trough-shaped. Device according to at least one of the preceding claims,
characterized in that
the recess (133) has rounded edges (135). Device according to at least one of the preceding claims,
characterized in that
the depth of the recess (133) is less than the length and the width of the recess (133). Device according to at least one of the preceding claims,
characterized in that
at least two symmetrically to the pressing surfaces (21, 123) arranged recesses (133) are provided. Device according to at least one of the preceding claims,
characterized in that
the recess (133) is disposed on a side surface (129) of the lower die (119). Device according to at least one of the preceding claims,
characterized in that
the lower die (119) has at least one further recess (133) provided outside the pressing surface (123). Device according to at least one of the preceding claims,
characterized in that
the lower die (119) below the pressing surface (123) has a taper, and that the width of the lower die (119) in the region of the pressing surface (123) is greater than in the region of the taper. Device according to at least one of the preceding claims,
characterized in that
a recess (133) is disposed on a side surface (27) of the upper die (17). Device according to at least one of the preceding claims,
characterized in that
the upper die (17) has at least one further recess (133) arranged outside the pressing surface (21). A lower die (119) for a device (111) according to at least one of the preceding claims,
characterized in that
the lower die (119) has at least one recess (133) outside a pressing surface (123) in order, during abutment of a line (13) on a connecting element (15), a part of the line (13) and / or a part of the connecting element (15 ). Upper die (17) for a device according to at least one of claims 1 to 11,
characterized in that
the upper die (17) has at least one recess (133) outside a pressing surface (21) in order, during abutment of a line (13) on a connecting element (15), a part of the line (13) and / or a part of the connecting element (15 ). Method for striking a line (13) to a connecting element (15), in which method
the line (13) and the connecting element (15) in a predetermined area between each one pressing surface (21, 123) an upper die (17) and a lower die (119) are pressed, and
a portion of the conduit (13) and / or a portion of the connecting member (15) as it leaves the area between the pressing surfaces (21, 123), into one between the upper die (17) and the lower die (119) outside the pressing surfaces (13) 21, 123) is received in order to avoid damage to the upper die (17) and / or the lower die (119).

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