Patent Publication Number: US-6702611-B1

Title: Shielded connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a shielded connector for mounting on a shielded wall of electrical equipment or to a terminal to be mounted to a shielded cable. 
     2. Description of the Related Art 
     FIGS. 9 and 10 illustrate an example of a shielded connector to be mounted to a terminal of a shielded cable, which was disclosed in Japanese Patent Laid-Open No. 7-245153. The connector housing  109  included in the shielded connecter  100  has a double structure comprising an inner housing  101  and an outer housing  102  formed in the shape of a cylinder of a synthetic resin being superimposed one on another, a connecting wall  103  partly connecting between peripheral surfaces of the inner housing  101  and the outer housing  102 , a terminal fitting  104  received in the inner housing  101 , and a shielding shell  105  formed in the cylindrical shape of a metal sheet inserted between the inner housing  101  and the outer housing  102 . The shielding shell  105  serves to enclose and to shield the periphery of the terminal fitting  104 , and a part of the outer housing  102  constitutes a cylindrical hood portion  107  opening toward the other corresponding part, to which the other corresponding connector  120  is fitted and locked by a locking arm  108  provided on the hood portion  107 . The terminal fitting  104  is provided with a shielded cable D 1  crimped thereon, and the shielding layer and the shielding shell  105  are conductively connected with respect to each other. 
     FIGS. 11 and 12 illustrate an example of a shielded connector to be mounted on the shielded wall of electrical equipment, which is presented in Japanese Patent Laid-Open No. 8-78098. The shielded connector  110  also comprises an inner housing  111  and the outer housing  112  constructed of a synthetic resin partly connected via a connecting wall (not shown), and a metallic shielding shell  115  inserted therebetween to enclose the terminal fitting  114  received in the inner housing  111 , wherein a part of the outer housing  112  constitutes a hood portion  116 , and the other corresponding connector (not shown) is engaged with the locking hole  120  formed on the hood portion  116 . The connector  110  is provided at the rear end of the outer housing  112  with a flange  117 , which is screwed to the shielded wall  119  with the packing mounted on the flange  117  crushed by the shielded wall  119 . The part of the flange  117  within the packing  118  is provided with a plurality of presser strips  115 B extending sideward from the rear end portion of the shielding shell  115 , the presser strips  115 B being pressed against the shielded wall  119  to conductively connect the shielding shell  115  and the shielded wall  119 . 
     The conventional shielded connectors  100  and  110  have a problem in that noises tend to leak through a slit (See  115 A, FIG. 11) formed on the shielded shell corresponding to the connecting wall for connecting the inner housing and the outer housing, thus resulting in degradation of shielding property. 
     Since the shielded connector to be mounted on the shielded wall  119  of electrical equipment includes presser strips  115 B on the flange  117 , the flange  117  has to be significantly large in size correspondingly, thereby requiring a large mounting space on the shielded wall  119 . 
     Since the flange  117  constitutes a part of the connector housing constructed of a synthetic resin, there is apprehension that the flange is deformed by heat and thus the screw that fix the flange  117  to the shielded wall  119  is loosened, thereby degrading the connection and waterproof property between the presser strips  115 B and the shielded wall  119 . 
     SUMMARY OF THE INVENTION 
     Accordingly, with the circumstanced described above in view, it is an object of the invention to provide a shielded connector that has superior shielding property, requires only a small mounting space when being mounted to electrical equipment, and has good resistance to water at the mounting portion. 
     The shielded connector according to a first aspect of the invention comprises a connector housing for accommodating a terminal fitting, a cylindrical hood portion provided on the connector housing for being fitted to the other corresponding connector, and locking means provided on the hood portion for preventing both of connectors from being detached, wherein the hood portion is constructed by mounting a cylindrically formed conductive member to the connector housing, and a shielding shell is constructed by enclosing the terminal fitting by the conductive member. 
     In this arrangement, since the cylindrical hood portion is constructed of a conductive material and thus the hood portion itself serves as a shielding shell, the terminal fitting may be enclosed without any clearance by the peripheral wall closed along the entire side surface of the conductive material, so that leaking of noises through the slit formed on the shielding shell may be avoided, thereby improving the shielding property. 
     A second aspect of the invention is the shielded connector as set forth in connection with the first aspect of the invention characterized in that the shielded wall provided on electrical equipment is formed with a mounting hole for mounting the connector therethrough, and the flange extending sideward from the conductive member is screwed against the shielded wall so that the conductive member and the shielded wall are conductively connected. 
     In this arrangement, since the flange extending from the conductive member constituting the shielding shell is fixed and conductively connected to the shielded wall, the space used for mounting on electrical equipment may be reduced in comparison with the conventional arrangement wherein the portion conductively connected to the shielded wall and the flange to be used for the purpose of fixing are provided independently. 
     A third aspect of the invention is the shielded connector as set forth in the first and second aspects of the invention, characterized in that the conductive member is constructed of metal. 
     In this arrangement, since the conductive member is constructed of metal, the strength and heat resistant property is improved, thereby preventing the deformation of the hood portion engaged with the other corresponding connector and the flange screwed onto the shielded wall. By providing a packing between the flange and the shielded wall, the packing is pressed against the shielded wall stably, thereby improving the waterproof property. 
     A fourth aspect of the invention is a shielded connector as set forth in any of the first to the third aspects, wherein a contact the middle portion of which is divided into a plurality of bands projecting sideward is fitted on the peripheral surface of the conductive member, and is resiliently in contact with the other corresponding shielding shell provided on the other corresponding connector. 
     In this arrangement, resilient force of the contact crashed between the conductive material as a shielding shell and the other corresponding shielding shell ensures the conductive connection between these shielding shells. 
     A fifth aspect of the invention is the shielded connector as set forth in any of the second to the fourth aspects of the invention, wherein the surface of the flange abutting against the shielded wall is formed with an annular groove near the inner edge thereof by pitting it in the direction away from the shielded wall, and the connector housing is provided with a inner flange projecting outward to be interposed between the inner wall of the annular groove and the shielded wall. 
     In this arrangement, the inner flange projecting outward from the connector housing is interposed between the shielded wall and the flange screwed onto the shielded wall to fix the connector housing onto the shielded wall together with the conductive member. 
     A sixth aspect of the invention is the shielded connector as set forth in any of the second to the fifth aspects of the invention, wherein the portion of the annular groove outside of the inner flange receives a packing that is interposed between the inner wall of the annular groove and the shielded wall in intimate contact therewith, and the packing is provide with a stopper projecting inwardly therefrom for being interposed between the inner flange and the inner wall of the annular groove. 
     In this arrangement, the stopper projecting inwardly from the packing is interposed between the inner flange and the inner wall of the annular groove to prevent the packing from being detached from the annular groove of the flange, thereby facilitating the operation to mount the shielded connector to the shielded wall. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side cross-sectional view showing a male and female shielded connectors according to an embodiment of the present invention. 
     FIG. 2 is a perspective view of the shielded connector shown in FIG.  1 . 
     FIG. 3 is an exploded perspective view of the male shielded connector. 
     FIG. 4 is a front view of the male shielded connector. 
     FIG. 5 a back view of the male shielded connector. 
     FIG. 6 is a side cross sectional view taken along the line A—A of FIG.  4 . 
     FIG. 7 is a side cross sectional view taken along the line B—B of FIG.  4 . 
     FIG. 8 is a side cross sectional view in the state that the male and female shielded connectors are connected. 
     FIG. 9 is an exploded cross sectional view of the shielded connector according to the conventional example  1 . 
     FIG. 10 is a side cross sectional view of the shielded connector according to the conventional example  1 . 
     FIG. 11 is an exploded perspective view of the shielded connector according to the conventional example  2 . 
     FIG. 12 is a side cross sectional view of the shielded connector according to the conventional example  2 . 
    
    
     DETAILED DESCRIPTION OF THE PRESENT INVENTION 
     Referring now to FIG. 1 to FIG. 8, an embodiment of the invention will be described in detail. In this embodiment, the invention is applied to the male shielded connector  10  shown in FIG. 1 on the left (hereinafter referred to as “male connector  10 ”), which is mounted on the shielded wall  60  provided on electrical equipment and is connected to the female shielded connector  11  shown on the right (hereinafter referred to as “female connector  11 ”). The description will be made referring to the sides of the respective connectors  11 ,  12  that face the other corresponding connector as “front”. 
     The female connector  11  will be described first, to which the present invention is not applied. The female connector  11  is fixed on the terminal of the shielded cable D 1 , and the female connector housing  12  constituting the female connector  11  and being constructed of an insulating resin (hereinafter referred to as “female housing  12 ”) comprises a housing body  13  and a hood portion  14  enclosing the front side of the housing body  13 , and a pair of cylindrical portions  15 ,  15  extending from the front end of the housing body  13  located at the back of the hood portion  14  in parallel. A pair of cavities  16 ,  16  is formed on each cylindrical portion  15  and the housing body  13 , through which female fittings  17  are received respectively and locked by the respective resin rances  16 A, as shown in FIG.  1 . 
     Each cylindrical portion  15  has a conventional structure, as shown in FIG. 1, such that the rear end of the small diameter cylindrical portion  15 B is received coaxially in the large diameter cylindrical portion  15 A projected from the front surface of the housing body, and the respective peripheral surfaces thereof are partly connected via a connecting wall, not shown. 
     As in the conventional arrangement, the shielded shell  18  having a slit corresponding to the connecting wall is inserted between both of cylindrical portions  15 A and  15 B and locked with the metallic rance  19  extending from the shielded shell  18  so that they are not detached. The rear end portion of the shielded shell  18  is conductively connected to the shielding layer of the shielded cable D 1  crimped to the female terminal fitting  17  via a metallic sleeve  21 . 
     The upper surface of the housing body  13  is provided with a locking arm  13  in the shape of a seesaw as shown in FIG. 1, and the portion of the locking arm  24  extending forward from the fulcrum is received into the hood portion  14  via the notch  14 W formed on the proximal end of the hood portion  14  (See FIG. 1) 
     The rear end opening of the cavity  16  is sealed with the rubber plug  22  fitted into the shielded cable D 1 , and a rubber ring  23  is fitted on the outer surface of the large diameter cylindrical portion  15 A, thereby ensuring watertightness between the fitted portion and the other corresponding connector. 
     The male connector  10  to which the present invention is applied is as follows. The male connector  10  comprises a male connector housing  30  (hereinafter referred to as “male housing  30 ”) and an aluminium sleeve  31  assembled thereon as shown in FIG.  1 . 
     The male housing  30  generally shown in the lower left of the FIG. 3 is constructed of an insulating resin, and comprises a base portion  32  being oval in cross section and flat in the direction of axis, a pair of cylindrical portions  33 ,  33  extending rearward from the rear end surface of the base portion  32  in parallel, and a resin flange  34  extending sideward from the rear periphery of the base portion  32 . As shown in FIG. 1, cavities  35  are formed through the respective cylindrical portions  33  and the base portion, to which the male terminal fitting  36  is received. 
     The male terminal fitting  36  is locked in the cavity  35  by the resin rance  39  with a tab  38  formed on the front end projected from the front opening  35  of the cavity  35  toward the front of the base portion  32 . The cable D 2  having no shielding layer is crimped to the male terminal fitting  36 , and is supported by the sleeve  40  (See FIG. 1) provided at the opening edge of the rear end of the cavity  35  so that it does not hang over the edge thereof. 
     The aluminium sleeve  31  generally shown on the upper right of FIG. 3 is an aluminium die-casting having conductivity, and configured as follows. The main body  51  being oval in cross section and extending forward and backward is provided with an aluminium flange  52  of horizontally extending rectangular at the rear end thereof, and the rear end surface of the aluminium flange  52  is formed with a recess  52  pitted axially up to the midway along the main body  51 , to which the base portion  32  of the male housing  30  is fitted (See FIG.  1 ). 
     The main body  51  is provided with a pair of communicating holes  53 ,  53  corresponding to the respective cavities  35 ,  35  in a forward-rearward direction, and one end of which is opening toward the inner face of the recess  52 A (See FIG.  3 ). The tab  38  of the male terminal fitting  36  projects from the front face of the base portion  32  of the male housing  30  into the inside of the communicating hole  53 , whereby the peripheral wall of the communicating hole  53  constitutes the hood portion  54  for receiving the other corresponding connector. 
     The inner peripheral surface of the hood portion  54  is formed with a projecting thread  56  projecting inwardly at the forward position thereof as shown in FIG. 1, and the contact  55  is assembled in the communicating hole  53  in such a manner that it is interposed between the projecting thread  56  and the front end surface of the male housing  30 . The contact  55  has a structure such that the middle portion of the cylindrical metallic sheet is divided into a plurality of bands being bent inwardly. 
     The upper surface of the main body  51  facing upward in FIG. 3 is provided with a locking projection  58  to be engaged with the locking arm  24 . 
     The aluminium flange  52  is, as shown in FIG. 3, formed with four boltholes at four corners therethrough. The bolts (not shown) are passed through the boltholes  95  and screwed to the shielded wall  60  with the aluminium flange  52  abutted against the peripheral edge of the connector mounting hole  61  formed on the shielded wall  60 . 
     The portion of the surface  52 B of the aluminium flange  52  abutting against the shielded wall  60  is formed with an annular groove  62  near the inner edge thereof by pitting it in the direction away from the shielded wall  60 , and the resin flange  34  provided on the male housing  30  is abutted against the inner edge portion of the inner wall of the annular groove  62 , and the packing  63  is fitted on the resin flange  34 . The inner peripheral surface of the packing  63  shown in FIG. 3 is provided with stoppers  64 ,  64  extending from the upper portion and the lower portion toward each other, and as shown in FIG. 7, these stoppers  64  are interposed between the resin flange  34  and the inner wall of the annular groove  62 . Such an arrangement prevents the packing  63  from being detached. 
     The aluminium sleeve  31  and the male housing  30  are, as shown in FIG. 7, positioned and locked by press fitting a pair of pins  65 ,  66  projecting rearward from the aluminium sleeve  31  into a pair of press-fitting holes  67  and  68  formed on the male housing  30 . More specifically, the respective press-fitting holes  67  and  58  are provided with a plurality of projecting threads axially extending therein, which are crushed by the pins  65  and  66 , whereby the pins  65  and  66  are held in the press-fitting holes  67  and  68  respectively. In this arrangement, the male housing and the aluminium sleeve  31  are integrated. 
     The effect of this embodiment will be now described. 
     In order to assemble the male connector  10  to the shielded wall  60  of electrical equipment, the rear end portion (cylindrical portion  33 ) of the male connector  10  is inserted into the connector mounting hole  61  formed on the shielded wall  60  and the aluminium flange  52  is abutted against the peripheral edge portion of the connector mounting hole  61 . During this operation, since the packing  63  is not detached because a part (stopper  64 ) thereof is interposed between the resin flange  34  and the inner wall of the annular groove  62 , the mounting operation can be carried out easily. 
     Then, the bolt is inserted into the bolthole  59  formed on the aluminium flange  52  and screwed into the threaded portion, not shown, formed on the shielded wall  60 . Then, the aluminium flange  52  is pressed against the shielded wall  60  so that the outer edge portion of the aluminium flange  52  comes into intimate contact with the shielded wall  60 , and the aluminium sleeve  31  as a shielding shell is conductively connected to the shielded wall  60 . The aluminium flange  52  here has high strength as distinct from the conventional flange constructed of a synthetic resin, the bolt may be tightened strongly, thereby ensuring the intimate contact between the aluminium flange  52  and the shielded wall  60  to stabilize the conductive connection therebetween. 
     When the aluminium flange  52  is pressed against the shielded wall  60 , the packing  63  is crushed by a prescribed extent so that watertightness between electrical equipment and the male connector  10  is ensured. The resin flange  4  provided on the male housing  30  is interposed between the shielded wall  60  and the aluminium flange  52  so that the male housing  30  is fixed on the shielded wall  60  together with the aluminium sleeve  31 . 
     Subsequently, the female connector  11  is connected with the male connector  10 . Then, as shown in FIG. 8, the tab  38  of the male terminal fitting  36  is inserted into the cavity  16  of the female connector  11  and the conductively connected to both of the terminal fittings  17  and  36 , and the locking arm  24  formed on the female connector  11  goes beyond and is engaged with the locking projection  58  formed on the upper surface of the male connector  10 , so that both of the connectors  10  and  11  are prevented from being detached. 
     The contact  55  is interposed between the inner peripheral surface of the hood portion  54  of the male connector  10  and the outer peripheral surface of the shielding shell  18  of the female connector  11 , and the bent portion thereof is crushed. By this action, the aluminium sleeve  31  as a shielding shell is reliably and conductively connected to the other corresponding shielding shell  18 . 
     The passage of electric current passes through the cables D 1  and D 2  causes noise therearound. However, since the hood portion  54  itself serves as a shielding shell in the male connector  10  of the present embodiment, and the hood portion  54  completely enclose around the male terminal fitting  36  without any clearance, leakage of noise from the slit of the shielding shell as in the conventional connector is prevented, thereby improving the shielding property. Though a slit is formed on the other corresponding shielding shell  18 , noises leaked from there may be shielded because the hood portion  54  encloses the outside of the slit. 
     In addition, since the aluminium flange  52  to be screwed on the shielded wall  60  is constructed of a metal, it has higher strength and heat resistant property in comparison with the conventional flange constructed of a synthetic resin. Therefore, deformation of the flange may be prevented and the conductivity between the shielded wall  60  and the aluminium sleeve  31  may be maintained in a stable manner even when the shielded cable D 1  is pulled, thereby improving the reliability of the shield. Likewise, since the packing  63  is stably pressed against the shielded wall  60 , high resistance to water may be established. 
     As is described thus far, according to the male connector  10  of this embodiment, the shielding property can be improved by enclosing around the male terminal fitting  36  by the aluminium sleeve  31  without any clearance. In addition, since it is constructed in such a manner that the aluminium flange  51  itself that fix the male connector  10  onto the shielded wall  60  is conductively connected to the shielded wall  60 , the space to be used when mounting on electrical equipment may be reduced in comparison with the conventional connector wherein the portion conductively connected to the shielded wall and the flange to be used for the purpose of fixing are provided independently. 
     It is understood that the present invention is not limited to the embodiment described here in accordance with the description above and the attached drawings, but embodiments as shown below are also included in the technical scope of the present invention, and embodiments other than the ones shown below may be made by various changes without departing from the scope thereof. 
     (1) While the packing  63  of the embodiment described above is provided with a pair of stoppers  64 , the stopper may be formed in such a manner that it extends all around the packing. 
     (2) While, in the embodiment described above, there is shown the shielded connector to be connected to the shielded wall  60  of electrical equipment to which the present invention is applied, it is also possible to apply the present invention to the shielded connector to be mounted at the terminal of the shielded cable. 
     (3) While, in the embodiment described above, there is shown the male connector  10  including a male terminal fitting received therein to which the present invention is applied, it is possible to apply the present invention to the female connector including a female terminal fitting received therein. 
     (4) While the contact  55  is provided within the aluminium sleeve  31  in the embodiment described above, it is also possible to eliminate the contact and to provide a resilient portion on the shielding shell of the other corresponding connector. 
     (5) While the bolt is screwed through the aluminium flange  52  in the embodiment described above, it is also possible to form a cylindrical wall extending rearward from the base portion  32  of the male housing  30  so that it can pass through the connector mounting hole  61 , and cut threads on the outer peripheral portion of the cylindrical wall so that the nut can be screwed thereon. 
     (6) While, in the embodiment described above, there is shown an aluminium die-cast aluminium sleeve  31  as a conductive member according to the invention, metals other than aluminium (for example, iron, copper, zinc, lead, magnesium, and so on) may be use as far as it has conductivity, or a part that corresponds to the conductive member according to the invention can be formed by a conductive resin.