Patent Document

[0001]    This application is a §371 National Stage Entry of PCT International Application No. PCT/EP2015/068476 filed on Aug. 11, 2015. PCT/EP2015/068476 claims priority of DE 202014103754.3 filed Aug. 13, 2014. The entire contents of these applications are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The invention relates to a connection terminal for a continuous electrical conductor, in particular a ground conductor. 
         [0003]    Electrical devices, for example, machines and apparatuses, are grounded for the protection of humans and animals against electrical shock. For this purpose, electrically conductive components of the devices such as housing components which may come in contact with a person and which are not part of the operating current circuit of the electrical machine or of the housing are connected to a ground line. This ground line is connected to ground of the supply voltage network. The devices can also be grounded jointly or separately via a protective ground such as for example, in the ground. 
         [0004]    In order to ground the electrical devices jointly, a grounded conductor is connected to all the devices. For this purpose, a continuous ground conductor is used. 
         [0005]    The purpose of the subject matter of this disclosure is to provide an easy-to-handle connection terminal which enables a rapid and reliable connection of the electrical devices to the continuous ground conductor without splitting said ground conductor. 
       SUMMARY OF THE INVENTION 
       [0006]    The connection terminal is provided for the connection of an electrical device to a continuous electrical conductor, in particular a ground conductor. The conductor preferably includes multiple strands or wires surrounded by an insulation material. The connection terminal has a connector body which includes a terminal connection containing a recess extending in a direction through which the electrical conductor extends. In addition, the connection terminal includes a holding device to at least partially close the recess. The holding device is reversibly adjustable from an open position in which the electrical conductor can be inserted into the recess to a closed position. In the closed position, the holding device holds the electrical conductor in a radial direction around the extension direction in the recess. 
         [0007]    The holding device is reversibly rotatable in a direction of rotation around an axis extending in the extension direction or displaceable in a sliding direction which extends transverse to the extension direction. In addition, the terminal connection includes a clamp which clamps the electrical conductor and/or the holding device in the closed position. 
         [0008]    Therefore, the electrical conductor can be connected with the connection terminal merely by inserting the conductor into the recess in the direction of extension of the conductor and by adjusting the holding device from the open position to the closed position 
         [0009]    Preferably, the holding device is rotatably connected with the connector body. 
         [0010]    The holding device includes a contact surface for receiving the electrical conductor in the open position. Preferably, the contact surface holds the electrical conductor in the closed position within the recess. For this purpose, the holding device includes a first arm on which the contact surface is arranged. In this embodiment, the electrical conductor applied against the contact surface is placed in the recess when the holding device is rotated. This can be done rapidly and simply. 
         [0011]    The first arm is provided in order to at least partially close the recess in the closed position. 
         [0012]    Particularly preferably, the connector body and the first are of the holding device jointly surround the electrical conductor in the closed position. Most particularly, they surround the entire periphery of the electrical conductor. 
         [0013]    In order to prevent the holding device from becoming detached in the closed position and to hold the ground conductor securely in the connection terminal even under strong vibrational stress, the terminal connection includes a clamping device. The clamping device is provided in order to clamp the holding device in the closed position. 
         [0014]    In a first preferred embodiment, the clamping device acts directly with the holding device. In a second preferred embodiment, the clamping device acts indirectly with the holding device. 
         [0015]    The clamping device is preferably a clamping screw which is adjustable in a clamping direction and counter to the clamping direction transversely to the extension direction of the electrical conductor and which ensures the contact position. The clamping screw preferably has a clamping surface. The clamping surface is preferably arranged at an open end of the clamping screw and extends transversely to the direction of rotation of the clamping screw. 
         [0016]    In a first embodiment, in the closed position, the clamping surface abuts directly against the holding device, in particular against a second arm of the holding device. In a second embodiment, in the closed position, the clamping surface butts directly against the electrical conductor. In this embodiment, the clamping device acts on the electrical conductor together with the holding device, preferably with the second arm of the holding device. The second arm in this embodiment acts as a lever, on the end of which the first arm is arranged. In both embodiments, the clamping device prevents undesired adjustment of the holding device from the closed position into the open position so that the electrical conductor is reliably held in the closed position. 
         [0017]    The holding device is designed in the shape of an L and can be produced easily and cost effectively as a punched element. 
         [0018]    The holding device is rotatably mounted in a bearing bore of the connector body so that it can be easily rotated. Moreover, the holding device includes a through bore to accommodate a rotary shaft such as a cotter pin which is arranged between the first arm and the second arm. In the open position, the holding device thereby forms a support which, when the holding device is rotated, guides the electrical conductor in the direction of rotation into the recess. In the closed position, the second arm of the holding device can be used for clamping the holding device. 
         [0019]    The rotary shaft is preferably formed as a bar or a spring cotter pin. As a result, the cotter pin is self-retaining. 
         [0020]    The connection terminal includes a conductor connection for connection of an additional electrical conductor. The additional electrical conductor is preferably a connection conductor of the electrical device, wherein the electrical conductor is preferably a ground conductor. The conductor connection can be designed either as a terminal connection or as a conventional conductor connection. 
         [0021]    The connection terminal preferably has a plane symmetric or point symmetric design. In this embodiment, it also includes a terminal connection with a recess in which the continuous conductor can be inserted in the extension direction thereof and connected. However, in another embodiment of the connection terminal, the connection terminal also includes such a terminal connection but does not have a symmetric design. In yet another embodiment, the conductor connection is a conventional conductor connection which is formed for the connection of a conductor end such as a push-in connection. 
         [0022]    The connection terminal is electrically conductive. Preferably it is manufactured from a metal such as brass or a metal alloy. The terminal has a low-ohmic design and good current load capacity. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0023]    Other objects and advantages of the invention will become apparent from a study of the following description when viewed in the light of the accompanying drawing, in which: 
           [0024]      FIGS. 1 a  and 1 b    are exploded and cross-sectional views, respectively of a connection terminal according to a first embodiment of the invention; 
           [0025]      FIGS. 2 a  and 2 b    are exploded and cross-sectional views, respectively, of a connection terminal according to a second embodiment of the invention; 
           [0026]      FIG. 3 a    is an exploded view of a connection terminal according to a third embodiment of the invention; and 
           [0027]      FIGS. 3 b  and 3 c    are sectional views of the terminal of  FIG. 3 a    in the open and closed positions, respectively. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    Referring first to  FIGS. 1 a  and 1 b   , a first embodiment of a connection terminal  1  will be described. 
         [0029]    The connection terminal  1  includes a connector body  2  and a terminal connection  20  including at least one recess  21  which extends in an extension direction  43 . More particularly, the extension direction is the direction along which an electrical conductor adapted to be connected with the connection terminal extends. As shown in  FIG. 1 b   , a continuous electrical conductor  5  is inserted into the recess in the extension direction  43 . The connection terminal  1  provides an electrically conductive connection between two electrical conductors  5  such as a ground conductor  51  and a connection conductor  52  to ground an electrical device (not shown). The connection terminal can also be used to provide an electrical connection between two electrical conductors  5  having another function. 
         [0030]    In order to hold or retain the electrical conductor  5  within the recess  21 , the connection terminal  1  includes a holding device  31 . The holding device  31  at least partially and preferably completely closes the recess  21 . For this purpose, the holding device  31  is connected with the connector body  2  for rotation around an axis  4  extending in the extension direction  43 . 
         [0031]    The holding device  31  is configured in the shape of an L and includes a first arm  312  and a second arm  313 . In the area where the first arm  312  joins the second arm  313 , a through bore  314  is provided. 
         [0032]    The connector body  2  includes a bearing bore  24 . In a mounted state, the bearing bore  24  of the connector body  2  and the through bore  314  of the holding device  31  are arranged in alignment with one another to receive a rotary shaft  32  which extends concentrically with the axis  4 . 
         [0033]    The holding device  31  is mounted in a fixed manner on the rotary shaft  32 . The rotary shaft  32  passes through the bearing bore  24  and the through bore  314 . As a result, the holding device  31  turns or rotates with the rotary shaft  32  in a direction of rotation  41  or counter to it around the axis  4 . Accordingly, the holding device can be turned in the direction of rotation  41  from an open position  0 , in which the electrical conductor  5  can be inserted in the recess  21 , to a closed position G, in which the holding device  31  holds the electrical conductor  5  in a radial direction  40  around the axis  4  in the recess  21 . The open  0  and closed G positions of the holding device are shown in particular in connection with the embodiment of  FIGS. 3 b    and  3   c.    
         [0034]    The holding device  31  has a contact surface  311  for connection with the electrical conductor  5 . The contact surface  311  is arranged on the first and second arms  312 ,  313 . It extends on an inner surface of the first and second arms  312 ,  313  which faces the connector body  2  particularly when the holding device is in the closed state G. 
         [0035]    In order to place the electrical conductor  5  in the recess  21 , the electrical conductor  5  is placed against a contact surface  311  of the holding device when the device is in the open state  0  as shown in  FIG. 1 b   . By rotating the holding device  31  in the direction of rotation  41 , the electrical conductor is introduced into the recess  21  which is closed simultaneously by the holding device  31  and particularly by the first arm  312  of the holding device  31  as shown in  FIG. 1   b.    
         [0036]    In the closed state G of the holding device  31 , the electrical conductor  5  is held with the first arm  312  of the holding device  31  in the recess  21 . The first arm  312  almost completely closes the recess  21 . The first arm  312  and the connector body  2  therefore jointly almost completely surround the electrical conductor  5  in the closed position G. The electrical conductor  5  is then held captive in the recess  21 . The recess  21  is dimensioned so that, in the closed position G, the electrical conductor  5  contacts the connector body  2  in an electrically conductive manner. For that purpose, the connector body  2  is electrically conductive so that no additional components are needed for producing an electrically conductive contact between the electrical conductor  5  such as the ground conductor  51  and an additional electrical conductor  5  such as the connection conductor  52  connected to the connector body  2 . 
         [0037]    In order to hold the holding device  31  in the closed position G, the terminal connection  20  further includes a clamping device  33 . The clamping device  33  is preferably a clamping screw. The clamping screw is connected with a through bore  23  of the connector body  2  which extends transversely to the extension direction  43  and is adjusted via rotation in a clamping direction  42  from a home position P into a securing position S securing the holding device  31  in the closed position G. The clamping device  33  has a clamping surface  331 , which is arranged on a lower end  332  of the clamping device  33  facing the recess  21 . The clamping surface  331  extends transversely to the clamping direction  42 . 
         [0038]    In the embodiment shown in  FIGS. 1 a  and 1 b   , the clamping device  33  when rotated into the securing position S presses or clamps the electrical conductor  5  into the recess  21  when the holding device  31  is in the closed position G. 
         [0039]    For the clamping device  33  to hold the holding device  31  in the closed position G, the second arm  313  of the holding device is provided. The second arm  313  is at least partially arranged in a receiving groove  22  which is arranged under the recess  21  of the connector body. The receiving groove  22  extends into the connector body  2  of the connection terminal  1  and is arranged transverse to the extension direction  43  of the electrical conductor. 
         [0040]    In the closed position G, the holding device second arm  313  is accommodated in the receiving groove  22 . Since the electrical conductor  5  in the securing position S is pressed by the clamping device  33  in the clamping direction  42  into the recess  21 , the clamping device  33  acts indirectly on the holding device  31  in the securing position S via the electrical conductor  5 . As a result, the holding device  31  is held in the closed position G. 
         [0041]    The connection terminal  1  has a symmetric design with respect to a plane of symmetry  13  extending parallel with the extension direction  43 . The connection terminal  1  therefore includes two terminal connections  20  to which a respective continuous electrical conductor  5  can be connected. The terminal connections  20  are arranged on first and second sides  11 ,  12  of the plane of symmetry  13 . 
         [0042]    In addition, for each terminal connection  20 , two spaced parallel holding devices  31  are provided. The clamping device  33  for each of the two terminal connections  20  is arranged between the two holding device  31  of each respective terminal connection  20 . 
         [0043]      FIG. 2  shows an additional embodiment of a connection terminal  1 . However, in this connection terminal  1  only one holding device  31  is provided for each terminal connection for a respective electrical conductor  5 . The connection terminal  1  has a symmetric design with respect to an axis of symmetry  14 . It is also designed for the connection of two continuous electrical conductors  5 . 
         [0044]    The connection terminal  1  of this embodiment differs from the embodiment of  FIG. 1  moreover in that the holding devices  31  in each case act directly together with the clamping device  33  associated with the same terminal connection  20 . 
         [0045]    For this purpose, in the home position, the clamping device  33  abuts against a first contact point  315  of the second arm  313  of the holding device  31  when the holding device  31  is in the open position. By rotating the holding device  31  in the direction of rotation  41 , the holding device is rotated to the closed position G. In order to secure the holding device  31  in the closed position G, the clamping device  33 , which is preferably a clamping screw, is shifted by rotating in the clamping direction  42  until it butts against a second contact point  316  of the second arm  313  of the holding device  31 . 
         [0046]    An advantage of this embodiment is that the clamping device  33  does not press against the electrical conductor  5 . In addition, the electrical conductor  5  is clamped between the connector body  2  and the first arm  312  of the holding device  31 . As a result, the terminal connection  20  of this embodiment can be used for electrical conductors  5  of different conductor cross sections. The two closure variants work with different conductor cross sections. 
         [0047]    In the embodiment of  FIGS. 2 a  and 2 b   , the first arm  312  of a holding device  31  in the closed position G extends counter to the clamping direction  42  beyond the recess  21 . Therefore, the connector body  2  contains an indention  25  in alignment with the receiving groove  22  for the holding device  31  into which the second arm  312  protrudes when the holding device is in the closed position G. An electrical conductor  5  inserted in the recess  21  in the closed position G is therefore surrounded over its entire periphery by the connector body  2  and the holding device  31 . 
         [0048]    In the embodiment of the connection terminal  1  shown in  FIGS. 3 a   - 3   c,  only one of the conductor connections is designed in the form of a terminal connection  20  which is arranged here on the second side  12  of the connection terminal  1 . The connection terminal  1  further includes two conventional conductor connections  26 , which are formed, for example, as push-in connections. One of the two conductor connections  26  is arranged on the first side  11  of the connection terminal  1  and the other is arranged between the terminal connection  20  and the conductor connection  26  arranged on the first side  11 . The connection terminal  1  is therefore of asymmetric design. The conventional conductor connections  26  are in each case represented diagrammatically by a conductor connection opening  261  and a clamping screw  33  which is arranged in a bore  27 . 
         [0049]    The terminal connection  20  of this connection terminal  1  is similar to those of the connection terminal  1  described in connection with  FIGS. 2 a  and 2 b   .  FIGS. 3 b  and 3 c    show the collaboration of the clamping device  33  with the holding device  31  in the open position  0  and in the closed position G, respectively. 
         [0050]      FIGS. 3 b  and 3 c    show sections through the connector body  2  of the connection terminal  1  of  FIG. 3 a    on the second side  12 . The rotary shaft or pin  32  extends in the extension direction  43  and the holding device  31  is fixed on the rotary shaft  32 . In order to close the recess  21 , the holding device  31  and the rotary shaft  32  are jointly rotated around the axis  4  until the first arm  312  of the holding device engages in the indentation  25  of the connector body  2 . 
         [0051]    The rotary shaft  32  is designed as a spring cotter pin. As a result, the cotter pin is self-retaining, even in the case of severe vibrations. 
         [0052]    While the preferred forms and embodiments of the invention have been illustrated and described, it will be apparent to those of ordinary skill in the art that various changes and modifications may be made without deviating from the inventive concepts set forth above.

Technology Category: 5