Abstract:
The invention relates to a fuse holder comprising two housing elements which, once assembled, together form a tube in which a support for a fuse is accommodated. Each of the two housing elements comprises a contact for establishing an electrical contact with a terminal of a fuse housed in the support, when the support is installed between the assembled housing elements. The support may comprise means to ensure the correct position of each contact in its respective housing element. The support may also comprise means to ensure the correct orientation of the fuse in the support. The support may also comprise means for retaining a seal ensuring sealing between the two housing elements.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a national stage application under 35 U.S.C. §371 of PCT Application Number PCT/EP2014/078322 having an international filing date of Dec. 17, 2014, which designated the United States, said PCT application claiming the benefit of priority under Article 8 of the Patent Cooperation Treaty to French Patent Application No. 1363102, having a filing date of Dec. 19, 2013, the entire disclosure of each of which are hereby incorporated herein by reference. 
     TECHNICAL FIELD OF THE INVENTION 
     The invention concerns the field of fuse holders, and notably fuse holders for automotive applications. 
     BACKGROUND OF THE INVENTION 
     In particular, fuse holders of this type can be used to protect charging circuits of electric vehicles. Such circuits can carry currents of 63 amperes at 250 volts, for example. With such currents, the risk of overheating or even of fires occurring has to be taken under consideration. In order to eliminate, or at least to limit, this type of risk, the charging circuits are equipped with fuses. These fuses are advantageously placed as far upstream as possible in the charging circuit, for example at the level of the charging socket, in order to protect the vehicle and any occupants. 
     Given the importance of the protection role of these fuses, improvements to these fuses in order to increase their efficacy and reliability are looked for. 
     BRIEF SUMMARY OF THE INVENTION 
     To this end, there is provided in accordance with the invention a fuse holder including two housing elements. For example, once assembled, these two housing elements form a tube closed at each of its ends. They then make it possible to accommodate a fuse. A plurality of fuses may be accommodated in parallel between two housing elements. Each fuse includes two connecting terminals. Each housing element includes a contact intended to make an electrical connection with one of these terminals. To be more precise, two contacts are provided for each fuse, each situated in a respective housing element. Each contact is then intended to make an electrical connection with one of the two connecting terminals of a fuse. 
     The fuse holder further includes a support in which one or more fuses can be accommodated. The fuse holder is positioned inside the two housing elements assembled together so that each terminal is electrically connected to a contact. 
     The support makes it possible to increase the accuracy of the positioning of a fuse in a fuse holder, notably vis a vis the electrical connection between contacts and terminals, to the benefit of the reliability of the function implemented by this fuse. 
     In order to facilitate the insertion and the positioning of a fuse in a support, the support may be mounted on one of the housing elements in a mobile and/or removable manner. In this case, the support can occupy an open position in which the fuse can be mounted in the support. The support is then moved from this open position to a closed position in which the support is at least partly inserted in the housing element on which it is mounted. During this movement of the support, the support is guided in a precise manner by guide means in that housing element. Each fuse terminal is therefore also guided precisely toward a contact of this housing element, so that in the closed position each contact of this housing element and a terminal of the fuse are engaged one in the other. 
     There may equally be provision for the support to be movable to its closed position only if the fuse is correctly oriented and positioned in its support. The overall size of the exterior envelope of the support fitted with an incorrectly positioned fuse being greater than that of the exterior envelope of the support in which each fuse is correctly positioned, a snug opening is provided in the housing element on which the support is mounted in a mobile manner. Accordingly, if a fuse is not correctly positioned in the support, the latter cannot be moved through this opening. 
     The orientation and the positioning of a fuse in its support must be particularly precise, notably, for example, if the contacts are female contacts each receiving a respective pin extending from a terminal of the fuse, or vice versa. Accordingly, if the pin has a rectangular section, the support may include a slot, also rectangular and essentially perpendicular to the axis of the pin. The pin can then be snugly inserted in this slot, in accordance with an orientation enabling alignment of the pin with the opening of the female contact to make possible, or at least to facilitate, the introduction of the pin into the female contact when the support is moved from its open position to its closed position and/or when the housing elements are moved toward each other with a view to closing them. 
     Retaining means retaining the fuse on the latter can contribute to precise positioning of the fuse in its support and consequently of the fuse in the fuse holder. 
     There may equally be provided a support with locking reinforcing means known as primary lock reinforcement means or terminal position assurance means. For example, these locking reinforcement means may include a tongue that can be engaged behind a contact (here “behind” does not mean relative to the direction of insertion of the contact into its housing in a housing element but rather relative to a face of the contact perpendicular to this insertion direction), or a contact tongue, if that contact is correctly positioned in the housing element in which it is mounted. In other words, if the locking reinforcement means cannot be engaged behind this contact, the support cannot be moved, or at least not moved all the way, from its open position to its closed position, thereby indicating to the operative that the contact is not correctly positioned in the housing element in which it is mounted. 
     The fuse holder may also include a seal to provide the seal between the two housing elements. In this case, the support may include a retaining element such as a lug retaining the seal on one of the housing elements when the other housing element is not assembled thereto. This feature makes it possible to ship the fuse holder with a support pre-mounted on a housing element and with a seal already in place on the latter, whereas the contacts, the cables and the fuse will not be mounted until a later stage. 
     The housing element on which the seal is mounted may have a rim overlying the seal to protect it when the housing elements are not assembled together, for example during transportation steps. 
     Other features and advantages of the invention will become apparent on reading the following detailed description and from the appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       In these drawings: 
         FIG. 1  represents diagrammatically in perspective one embodiment of a fuse holder in accordance with the invention; 
         FIG. 2  represents diagrammatically in perspective an exploded view of the fuse holder from  FIG. 1 ; 
         FIGS. 3A and 3B  represent diagrammatically, in perspective, a support for the fuse holder from  FIGS. 1 and 2 , respectively without and with a fuse; 
         FIGS. 4A and 4B  represent diagrammatically, in perspective, a support mounted on a housing element of the fuse holder from  FIGS. 1 and 2 , with the support respectively in the open position and in the closed position; and 
         FIG. 5  represents diagrammatically in longitudinal section on an axial plane the fuse holder from  FIGS. 1 and 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     One example of a fuse holder  1  is represented in  FIG. 1 . That fuse holder  1  is inserted between two cable portions  2 , in an electrical circuit, such as a charging circuit of an electric vehicle. Each cable portion  2  is electrically connected, for example crimped or soldered, to a contact  3  (for example a Delphi female DCS1 contact  6 . 3  that can be seen in  FIG. 5 ). Each contact is accommodated in a housing element  4 ,  5 . A first housing element  4  includes locking means  6  for retaining a second housing element  5 , forming a cover. Once assembled, the first and second housing elements form a tube closed at each of its ends by a wall  7  including a passage  8  for each cable portion  2 . 
     As represented in  FIG. 2 , this fuse holder includes, in addition to the contacts  3  and the first and second housing elements  4  and  5 , a fuse support  9 , a fuse  10  and a seal  11 . The fuse  10  is accommodated in the support  9 , itself accommodated in the tube consisting of the first housing element  4  and the second housing element  5  assembled together. The seal  11 , mounted on the first housing element  4 , is inserted between the first housing element  4  and the second housing element  5 , in the manner of an interfacial seal, in order to provide the seal between them. Here the locking means  6  consist of two diametrically opposite elastic attachments  6   a  on the first housing element  4  each including a respective notch  6   b  (see  FIGS. 4A and 4B ) into which clips a lug  6   c  correspondingly situated on the second housing element  5 . The first housing element  4  essentially consists of a substantially cylindrical cap  4   a  with an external face  4   b  partially surrounded by a skirt  4   c.    
     The fuse  10  includes two terminals  10   a , from each of which extends a pin  10   b  forming a male contact adapted to be electrically connected with a female type contact  3 . 
     As represented in more detail in  FIG. 3A , the support  9  is in the shape of a cradle with two side walls  12  extending longitudinally between two flanges  13 . Two elastic lateral lugs  14  each extend from a respective side wall  12 . Each of these lateral lugs  14  includes a detent  14   a  to form means for retaining a fuse  10  in its support  9 , as shown in  FIG. 3B . 
     The support  9  also includes guiding and fixing means  15  ( FIG. 3A ). These include two diametrically opposite lugs  15   a  each including a respective hook  15   b  intended to retain or to lock the support  9  onto the first housing element  4 . These two lugs  15   a  constitute guide means that enable the support  9  to be guided and positioned precisely relative to the first housing element  4 . 
     Each flange  13  includes a slot  13   a . Each slot  13   a  is of essentially rectangular shape, open on an edge of the flange  13  oriented toward the top of the support  9 . Each slot  13   a  is intended to receive a pin  10   b  of the fuse  10 . Each pin  10   b  has an essentially rectangular cross section (i.e. a section perpendicular to the direction of insertion of the pin  10   b  into a contact  3 , which also corresponds to the direction A of assembly of the first housing element  4  and the second housing element  5 ). Each pin  10   b  can then be snugly inserted in a respective slot  13   a , as shown in  FIG. 3B . 
     The support  9  also includes locking reinforcement means  16 . These consist essentially of a tongue  16   a  extending longitudinally toward the exterior of the support  9  from each flange  13 . The function of these tongues  16   a  is described in more detail later, with reference to  FIG. 5 . 
       FIGS. 4A and 4B  respectively show the open and closed positions of the support  9  on the first housing element  4 . In the position corresponding to  FIG. 4A , the support  9  is in an open or pre-locked position. In this position the fuse  10  can be introduced into the support  9  without having to demount the latter from the first housing element  4 . The support  9  is retained, but mobile, on the first housing element  4  because the hooks  15   b  remain engaged in the posterior openings  17 . 
     When the fuse  10  is correctly positioned between the lateral lugs  14 , under the detents  14   a  and with the terminals  10   a  inserted in the slots  13   a , the support  9  can be moved longitudinally, toward its closed position, inside a cavity  18  in the cap  4   a  of the first housing element  4  and leading to an opening  19 . During this movement, the lugs  15   a  slide in diametrically opposite grooves  20  disposed longitudinally on the external face  4   b  of the cap  4   a . Accordingly, on insertion of the support  9  into the first housing element  4 , the latter is inevitably correctly oriented, so that the opening of the female contact  3 , which is accommodated in the first housing element  4 , is aligned with the corresponding pin  10   b.    
     If the fuse  10  is not correctly positioned in the support  9 , it projects from the external envelope which it should be inside. Its overall size is then such that it can no longer pass through the opening  19 . Because of this, the support  9  cannot be moved into the closed position (that corresponding to  FIG. 4B ) and the second housing element  5  cannot be locked onto the first housing element  4 . Thus the operative is alerted to incorrect mounting of the fuse  10 . Otherwise, the support  9  can be moved to its closed position, in which the hooks  15   b  clip into anterior openings  21  (see  FIG. 5 ). 
     The second housing element  5  can then be threaded onto the support  9  and around the cap  4   a , to be locked by the locking means  6 . As can be seen in  FIG. 1  in particular, the second housing element  5  includes poka-yoke means  25  enabling an operative to orient it correctly relative to the support  9 . Accordingly, upon its insertion onto the support  9 , the second housing element  5  is inevitably correctly oriented, and so the opening of the female contact  3  that is accommodated therein is aligned with the corresponding pin  10   b.    
     As shown in  FIG. 5 , the first housing element  4  and the second housing element  5  assembled in this way form a closed tube that is sealed by the interfacial seal  11  and the individual wire seals  24  crimped with the cable portions  2  onto the contacts  3 . 
     If the contacts  3  are correctly inserted in their respective housings of the first housing element  4  and the second housing element  5 , the locking tongues  22  spring into a cut-out  23  in the contacts  3  provided for this purpose. Accordingly, on inserting the support  9  in the first housing element  4 , and on mounting the second housing element  5  on the already constituted assembly of the first housing element  4  and the support  9 , the tongues  16   a  can be placed behind the contacts  3 , and to be more precise behind the tongues  22 . If on the other hand a contact  3  is not correctly inserted in its housing, the corresponding tongue  22  blocks the passage of a tongue  16   a  and either the support  9  cannot go to the closed position or the second housing element  5  cannot be fully locked onto the first housing element  4 . In both cases the operative is alerted to a mounting error. 
     As can also be seen in  FIG. 5 , the seal  11  is protected by a rim consisting of the skirt  4   c . The seal  11  is therefore protected even when the second housing element  5  is not assembled with the first housing element  4 . Moreover, the lugs  15   a  are able to retain the seal  11  on the first housing element  4 , under the skirt  4   c , when the support  9  is in the closed position (which advantageously corresponds to the shipping position of the assembly consisting of the first housing element  4  and the support  9 ). 
     It can equally be seen in  FIG. 5  that the second housing element  5  snugly surrounds the support  9  in which the fuse  10  is precisely accommodated, which fuse is itself connected to contacts  3  firmly and reliably locked in their respective housing thanks to the locking reinforcement means  16 . 
     A fuse holder with a single support for a single fuse has been described above, but in accordance with variants the fuse holder in accordance with the invention may include either a single support but one that is able to accommodate a plurality of fuses or a plurality of supports each accommodating one or more fuses. All these variants may have one or more of the features defined in the claims.